Fellowship Flashcards
What is the starting dose of Simvastatin?
40 mg. (To practice evidence based medicine you have to do what they do)
Hyperthyroidism: How would you dose methimazole if the free T4 is less than 2 ng/L?
10 mg/day.
Hyperthyroidism: How would you dose methimazole if the free T4 is 2 - 4 ng/L?
20 mg/day.
Hyperthyroidism: How would you dose methimazole if the free T4 is 4 - 6 ng/L?
30 mg/day
Hyperthyroidism: How would you dose methimazole if the free T4 is more than 7.8 ng/L?
20 - 30 mg bid or tid. Doses more than 40 mg/day not really more effective.
What should you check in all females before starting anti-thyroid drugs?
Pregnancy test.
Which anti-thyroid drug can be used in the first trimester of pregnancy?
PTU (Propylthiouracil).
If a patient with hyperthyroidism is pregnant and in the second or third trimester then which anti-thyroid drug would you use?
Methimazole.
Which five antibodies are associated with diabetes mellitus type 1?
- Anti-GAD (glutamic acid decarboxylase) 65 antibody.
- Islet cell antibody.
- Insulinoma associated protein 2 auto-antibody.
- Insulin auto-antibody.
- Zinc transporter 8 antibody
How long after starting anti-thyroid drugs should the WBC be checked?
3 - 7 days.
How should you change the dose of levothyroxine during pregnancy?
Increase by 20%. (Give 1 - 2 extra pills on the weekend).
Does it matter whether or not metformin is given in divided doses?
No it does not.
Why is metformin given in divided doses?
Because it causes diarrhea and GI upset if given all together.
How long does metformin take to show effects?
About 6 weeks.
Ideal method of initiating a patient on metformin.
Start with 250 mg after breakfast and dinner everyday. After a week or two 500 mg after dinner and breakfast. After another week or two 750 mg twice a day and then 1000 mg twice a day. This reduces GI complaints.
What is the likelihood of an identical twin having type 1 diabetes mellitus if the other twin has it?
About 30%.
What is the likelihood of an identical twin having type 2 diabetes if the other twin has it?
Almost 100%.
If the blood glucose is very high then why do the patients need very large amounts of insulin and take a long time to come back to normal?
They have hyperglycemic toxicity or glucose toxicity.
It’s better to just put them on a drip in the beginning to bring them down to normal sooner.
If you have diabetic retinopathy then do you have nephropathy?
You can. But not necessarily.
What’s the best treatment for very high triglyceridemia in a diabetic?
Insulin
What test can you order to determine a patient’s average blood glucose over the past 2 - 3 weeks?
Fructosamine test. (Glucose also binds to albumin, not just hemoglobin; and albumin only stays in circulation for 2 - 3 weeks.
What’s the most common cause of death in DKA patients?
Arrhythmias secondary to hypokalemia.
What does intensive treatment of hyperglycemia do to retinopathy in diabetic pregnant women?
Makes it worse in the short term. Long term treatment improves retinopathy regardless.
What are the main risk factors for developing lactic acidosis with metformin?
Older age and chronic kidney disease with creatinine clearance of less than 60.
What class of drugs does Saxagliptan belong to?
DPP-4 inhibitor. (Dipeptidyl peptidase-4)
Name the rapid acting insulins.
- Aspart (Novolog). 2. Lispro (Humalog). 3. Glulisine (Apidra).
Name the short acting insulins.
Regular insulin that comes under the name of: 1. Humulin R. 2. Novolin R.
Why is regular insulin used in a drip and not a shorter acting insulin?
Because duration of action is based on absorption from the subcutaneous tissue. All insulins have the same duration of action (and act exactly the same way) once they reach the intravascular space. Regular insulin is the cheapest so that’s why it is the one used.
Name the intermediate acting insulins.
NPH (protamine added to regular insulin) Trade names: 1. Novolin N. 2. Humulin N. 3. Novolin NPH. 4. NPH Iletin II. 5. Isophane.
Name the long acting insulins.
- Glargine. 2. Detemir.
Name the ultra-long acting insulins.
Degludec (Tresiba).
What is Ryzodeg?
Combination of Degludec and Aspart.
What is the onset of action for rapid acting insulins?
15 min.
When do rapid acting insulins peak?
60 minutes.
What is the duration of action of rapid acting insulins?
3-4 hours.
What is the onset of action of short acting insulins?
30-45 minutes.
When do short acting insulins peak?
90 minutes.
What is the duration of action of short acting insulins?
4-6 hours.
What is the onset of action of intermediate acting insulin?
2 hours.
When do intermediate acting insulins peak?
4-5 hours.
What is the duration of action of intermediate acting insulins?
8-12 hours.
What is the onset of action of long acting insulins?
4 hours.
When do long acting insulins peak?
They are not supposed to have a peak.
What is the onset of action for ultra-long acting insulin?
4 hours.
When does ultra-long acting insulin peak?
It should not have a peak.
What is the duration of action of ultra long acting insulin?
48-72 hours.
What is the duration of action of long acting insulins?
20-24 hours.
How much calcium is in an 8 ounce glass of milk?
200 - 250 mg.
Which foods contain oxalate and increase the risk of kidney stone formation?
- Chocolate. 2. Spinach (And rhubarb and beets) 3. Nuts (peanuts and almonds, as well as other nuts). 4. Tea 5. Wheat bran and strawberries.
What categories of nutrition do you need to ask about in someone with kidney stones?
- Dairy. 2. Salt. 3. Meat. 4. Oxalate.
What ketones are measured when you check for urinary ketones?
Acetoacetate.
What ketones are not measured when you check for urinary ketones?
Acetone and beta-hydroxybutyrate.
What is the likely cause of worsening ketosis in a patient with DKA who is already on an insulin infusion and fluids?
The acetone and beta-hydroxybutyrate is being converted to acetoacetate and therefore showing up in the measured urinary ketones.
What is the maximal allowable dose of metformin?
2500 mg
What is the maximal effective dose of metformin?
2000 mg
What is the approximate potassium deficit in a patient with diabetic ketoacidosis?
5 - 7 mEq/kg.
Next steps in a patient with DKA, normal renal function and an elevated potassium.
Start insulin and fluids. Recheck the potassium after 4 hours.
Next steps in a patient with DKA, normal renal function and a normal potassium.
Start insulin, fluids and put potassium in the fluids.
Next steps in a patient with DKA, normal renal function and a low potassium.
This is a bad prognostic sign. Do not start fluids immediately. Give potassium, wait for an hour and then start insulin and fluids with potassium in it.
How fast can you give potassium through a peripheral line?
10 mEq/hr.
How fast can you give potassium through a central line?
20 mEq/hr.
What is the fastest route to replace potassium?
Oral
Next steps in a patient with DKA, decreased renal function and an elevated potassium.
Start insulin and fluids.
Next steps in a patient with DKA, decreased renal function and a normal potassium.
Start insulin and fluids.
Next steps in a patient with DKA, decreased renal function and a low potassium.
Give insulin and fluids with potassium in it.
What are the criteria for diagnosing diabetes?
- HbA1c greater than or equal to 6.5%. 2. Fasting plasma glucose more than or equal to 126 mg/dl. 3. Oral glucose tolerance test with a two hour glucose of 200 mg/dl or more. 4. Patient with classic symptoms of hyperglycemia with a random blood glucose of 200 mg/dl or more.
How long without food is considered fasting for the purpose of testing for diabetes?
8 hours or more.
Name the sulfonylureas.
Glipizide. Glyburide. Glimeripride.
What is the mechanism of action of sulfonylureas?
Glucose independent increased insulin sensitivity.
How much do sulfonylureas decrease the HbA1c?
1 - 2%
What are the significant side effects of sulfonylureas?
Hypoglycemia and weight gain.
Are sulfonylureas a long term solution for type 2 diabetes mellitus?
They gradually become less effective and therefore only be used temporarily.
What vitamin do you need to check and replace if a patient is on metformin?
Vitamin B12
What is the recommended daily calcium intake for someone with primary hyperparathyroidism?
A moderate calcium intake. 1000 mg per day.
If the testosterone is less than 1.5 and the patient has secondary hypogonadism - what should you do?
Check a pituitary MRI.
What is the pooled testosterone level?
A level is checked in the morning; followed by two other levels 20 minutes apart. Then they are added. This is to minimize errors caused by cyclical variation in testosterone.
When is the FRAX score used to make decisions about treatment?
When a patient has osteopenia (not osteoporosis).
Do you need basal insulin with U500 as it’s regular insulin?
No. Because it behaves more like NPH.
How many types of amiodarone induced hyperthyroidism and mechanisms?
Type I: increased production because of iodine load. Type II: thyroiditis because of direct destruction by amiodarone. Type II is more common.
Do you have to give methimazole in divided doses?
No.
Why is methimazole given in divided doses?
Because it causes nausea.
How soon after beginning aminoglycosides can patients develop nephropathy?
4-5 days.
How soon after contrast is given can patients get acute renal failure from it?
Immediately.
Which statin causes the least myalgia complaints?
Pitavastatin (Livalo)
How much hydrocortisone is 5 mg of prednisone equivalent to?
20 mg.
If the baseline cortisol is above ____ then the patient does not have adrenal insufficiency.
15 - 18 mcg/dl.
How old does a woman need to be before you can make a diagnosis of osteoporosis?
50 years or older.
How can HIV cause osteopenia/osteoporosis?
- HIV proteins cause osteoblast apoptosis. 2. Chronic cytokine release causes increase osteoclastic activity. 3. Independent risk factor for causing low bone mineral density. 4. May cause hypogonadism.
Does chronic hepatitis C cause decreased bone mineral density?
Yes.
What kind of cancer can Hurthle cell neoplasm be classified as?
Thyroid follicular cancer.
What other electrolyte could be low if a patient remains hypocalcemic despite replacement?
Magnesium.
What endocrine cause do you need to check for in someone with a persistently high LDL despite being on a statin?
Check a TSH for hypothyroidism.
If a hypothyroid patient is having runs of ventricular tachycardia, will giving him thyroid hormone exacerbate this?
No, there is no evidence to suggest this. The thyroid situation is not causing the ventricular tachycardia.
If there is tenderness over the sternum and anterior thighs what can this indicate?
Osteomalacia.
What diagnosis do you need to think of if a patient has abnormal fat distribution, an abnormal lipid panel and a family history of abnormal lipids?
Lipodystrophy.
Young Indian patients with pancreatitis and diabetes may have it because of…
Genetic mutation… Pancreas has calcifications.
A patient presenting with new onset diabetes and a new onset blistering rash… What will you think of?
Glucogonoma.
Can vitamin D deficiency in utero and childhood increase the risk of hip fracture later on life?
Yes
What does sunlight do to excess vitamin D?
Destroys it.
Which form of vitamin D is available by prescription in the US?
Vitamin D2
What does low magnesium do to the parathyroid hormone in the setting of vitamin D deficiency?
Blunts the response so instead of increasing the parathyroid hormone levels are normal.
What does vitamin D deficiency do to muscles?
Causes muscle weakness.
True or false. Vitamin D deficiency can make you more susceptible to tuberculosis.
True.
What do bisphosphonates do to osteoclasts?
Inhibit activity.
Which bisphosphonate is the most potent?
Zoledronic Acid
Do nitrogen-containing bisphosphonates accumulate in the body?
Yes. Bind to hydroxyapatite crystals.
Name four bisphosphonates in order of potency.
Zoledronic Acid (1) Risedronate (3) Alendronate (17) Pamidronate (67)
What is the bioavailability of oral bisphosphonates?
Less than 1%
What is the bioavailability of IV bisphosphonates?
100%
Infusion time for zoledronic acid?
15 min
Infusion time for pamidronate.
1 - 4 hours.
Infusion time for Ibandronate.
15 - 30 sec.
How much zoledronic acid is excreted renally and how much remains in the skeleton?
Excreted renally: 40% Remains in skeleton: 60%
What can be used to reduce incidence and severity of side effects from zoledronic acid infusion?
Acetominophen four times daily for three days.
Name some symptoms caused by zoledronic acid infusion.
Fever Eye inflammation Musculoskeletal pain GI symptoms Fatigue Influenza-like symptoms
What kind of renal injury can zoledronic acid cause?
Acute tubular necrosis
Why does the infusion of zoledronic acid have to be given over 15 minutes?
To reduce renal toxicity.
How would you try to reduce renal toxicity in a patient who is more at risk of nephrotoxicity from zoledronic acid?
Increase time taken to infuse to 30 minutes.
What creatinine clearance is zoledronic acid contraindicated at?
Less than 35 ml/min for 5 mg dose. Less than 30 ml/min for 4 mg dose. Dose adjustment for under 60 ml/mg possible.
In bisphosphonate therapy - what is the risk of osteonecrosis of the jaw dependent on?
Potency and duration of treatment.
How long after bisphosphonate therapy can osteonecrosis of the jaw develop?
Months to years.
First line drug for osteoporosis in men according to Endocrine Society Guidelines 2012. (Regular old osteoporosis)
Oral alendronate (generic)
When to use zoledronic acid instead of alendronate for osteoporosis in men?
- Secondary prevention of hip fracture. 2. GERD, malabsorption, cognitive problems, inability to be compliant because of too many meds or some other reason. 3. Non-metastatic prostate cancer on ADT. 4. HIV patients (they have been found to be more non-compliant) with orals.
Should you use heparin to lower triglycerides?
Usually not. You don’t want to transform it to hemorrhagic pancreatitis.
What type of cholesterol is responsible for triglycerides in the blood?
Chylomicrons and VLDL.
Pale pink blood vessels in the retina secondary to very high triglycerides.
Lipemia retinalis.
What kind of lesions can appear on back etc if the triglycerides are very high?
Eruptive xanthomas.
How long after radioactive iodine does TSH remain suppressed?
Months.
Are malignant thyroid nodules hypo- or hyperechoic?
Hypoechoic.
If a thyroid nodule has micro calcifications what does it make you think of?
Malignancy.
What are the indications for parathyroidectomy in primary hyperparathyroidism?
- Age less than 50 years. 2. Creatinine clearance less than 60. 3. Calcium more than 1 g/dl above the reference range for normal for that lab. 4. Osteoporosis on DEXA scan
What happens to the 1,25 OH vitamin D level in primary hyperparathyroidism?
It increases.
Can you treat osteoporosis in patients with cancer especially prostrate with PTH?
No. It would increase the likelihood of bone metastasis.
If someone has osteoporosis with few risk factors what should you think of?
Increased calcium excretion in the urine. Measure 24 hour calcium excretion.
How should you treat people who have osteoporosis due to increased calcium excretion in the urine?
Thiazide diuretics. These can increase BMD about as much as bisphosphonates in these patients.
Can hyperglycemia increase risk of getting dementia?
Yes
How many grams of carbohydrates in one can of Fibersource HN?
It has 250 ml of liquid nutrition. And 40 grams of carbohydrates.
Can LDL be checked without the triglycerides needed for calculation?
Yes, it can be directly measured.
What do nitrates do to bone mineral density and fracture risk?
Nitrates increase the nitric oxide levels which is associated with increased bone mineral density and deceased fracture risk.
Does metformin cause hypoglycemia?
Not on its own.
Does metformin play a role in causing hypoglycemia in patients on multiple anti diabetic medications?
Yes, it can exacerbate hypoglycemia caused by other agents.
Name two biguanides.
Metformin Phenformin
Why was phenformin withdrawn from the US market in 1976?
High rate of severe lactic acidosis
Should you give metformin if a patient has hepatic insufficiency?
No
Mechanisms by which metformin causes lactic acidosis.
- Promotes conversion of glucose to lactate in the splanchnic bed of the small intestine. 2. Inhibits gluconeogenesis from lactate, pyruvate, and alanine, resulting in additional lactate and substrate for lactate production.
How much does the sodium drop for every 100 mg/dl of glucose?
1.6 - 2.4 mEq/L
Is there any evidence that insulin can cause transaminitis?
Only case reports.
How are glucose levels related to risk of dementia?
Higher average glucose values result in higher risk for dementia; even in people without diabetes. Even an average glucose of 115 mg/dl compared to 100 mg/dl confers a higher risk - shown by study published in NEJM in August, 2013.
Which hormone secreted by the liver and white fat induces pancreatic beta cells to proliferate - as discovered in 2013.
Betatrophin. New discovery reported by Nature in April, 2013; and published in NEJM in August, 2013.
What are the criteria for surgery in primary hyperparathyroidism?
- Calcium more than 1 mg/dl above reference range for normal. 2. T score less than -2.5 on DEXA. 3. Stage 3 chronic kidney disease or worse. 4. Urine calcium more than 400 mg (old recommendation) 5. Age less than 50 years.
Goal for TSH in pregnancy.
Less than 2.5.
Does insulin resistance change during the day?
Increased insulin resistance during the day time so more basal requirement during the day time.
What is the mechanism of action of canagliflozin?
Decreases the renal threshold for excreting glucose so glucose starts appearing in the urine at 70 mg/dl.
What takes up sestamibi?
Metabolically active mitochondria.
How much calcium % is in calcium gluconate?
9%
What happens to bone density if you have continuous PTH exposure?
Bone density decreases.
What happens to bone density if you give PTH in a pulsatile fashion?
Bone density increases.
How much does a normal parathyroid gland weigh?
40 mg
Which statin causes the most transaminitis?
Atorvastatin.
Which statin has an FDA warning for increased concentrations and side effects in Asians?
Rosuvastatin
What statin and what dose is commonly used in patients who have had a coronary event?
Atorvastatin 80 mg qday.
What do statins do LDL receptors?
Increases expression of LDL receptors in the hepatocytes.
Do statins increase the risk of cancer?
No.
Do statins increase the risk of developing diabetes?
Yes.
Do statins cause cognitive dysfunction?
Yes. Memory loss, forgetfulness, confusion.
What happens if you give bile acid sequesters to patients with high triglycerides?
Their triglycerides and cholesterol may get worse.
Are lower doses of ezetimibe effective at reducing LDL?
Yes.
Can gemfibrozil monotherapy reduce vascular events?
1 - 2 trials have shown benefit in selected patients.
Which tests are good at identifying which women do not have gestational diabetes?
- Oral glucose tolerance test. 2. Fasting plasma glucose level. - at 24 weeks of gestation.
Which test is best at identifying women withgestational diabetes mellitus?
Oral glucose tolerance test.
Name three main complications that treating gestational diabetes mellitus prevents?
- Macrosomia. 2. Shoulder dystocia. 3. Pre-eclampsia.
Short-duration studies - what does salsalate do to glycemia?
Salsalate improves glycemia in patients with type 2 diabetes mellitus and decreases inflammatory mediators.
Name the commonly used statins in increasing order of potency.
Fluvastatin (80 mg) = Lovastatin and Pravastatin (40 mg) = Simvastatin (20 mg) = Atorvastatin (10 mg) = Rosuvastatin (5 mg)
Should you start metformin in pre-diabetics?
You can with the idea of slowing their progression to diabetes.
What are the limitations of thyroid nodule pathologic evaluation?
There is substantial inter- and intraobserver variability in cytopathologic and histopathologic evaluation of thyroid nodule confirming an inherent limitation of visual microscopic diagnosis.
Should you use a GLP-1 agonist in someone with a history of pancreatitis?
No. It’s contra-indicated.
What does metolazone do to calcium excretion?
Decreases calcium excretion thus causing hypercalcemia.
If the Achilles’ tendon is thick and nodular; what should you think of?
Tendon xanthoma.
Does adrenal insufficiency typically cause somnolence?
No.
How long after giving methimazole can you give propylthiouracil?
8 hours
If a patient has an LDL that is not at goal and triglycerides over 500 mg/dl then what do you treat first?
Triglycerides to reduce the risk of pancreatitis.
When is progesterone elevated in a female (above 1 ng/ml)?
- Pregnancy 2. Luteal phase (second phase of menstrual cycle).
What does estrogen do to cortisol?
Increases the total cortisol because estrogen increases the cortisol binding globulins.
What’s the loading dose of methimazole in thyroid storm?
60 mg.
What is the loading dose of propylthiouracil for thyroid storm?
1000 mg
What rate should you run a calcium gluconate drip at for someone with severe hypocalcemia?
0.5 mg/kg every hour. Run it a little slower in ESRD as patient will not be able to urinate it out.
How many ml in one ampule of calcium gluconate?
10 ml
How many mg of calcium gluconate in one ampule?
1000 mg (100 mg/ml)
How many mg of elemental calcium in one ampule of calcium gluconate?
93 mg
What’s the maximum amount of calcium carbonate you can absorb at one time?
600 mg. So makes more sense to give it more frequently.
What strength does Armour thyroid come in?
15 mg and 30 mg.
Is there any way to make a hyperthyroid patient euthyroid faster for surgery?
Can try iopanoic acid in addition to conventional treatment. It’s an iodine containing radiocontrast medium.
How much hydrocortisone is equivalent to 1 mg of dexamethasone?
26 mg
What do you need to check before starting a woman on high dose methimazole for suspected thyroid storm?
Pregnancy test.
If a woman is not having periods and therefore has unopposed estrogen what does she need to have done?
Endometrial biopsy to rule out endometrial cancer.
Which osteoporosis medications cause atypical fractures?
Bisphosphonates Donesumab
What dosages (mcg) does levothyroxine come in?
25, 50, 75, 88, 100, 112, 125, 137, 150, 175, 200, 300.
Why should you ask or check if the patient has had any imaging studies within the past few weeks/months if they come in with thyrotoxicosis?
To see if they have had IV contrast (iodine load) that may have contributed.
Does radioactive iodine ablation play a role in anaplastic thyroid cancer after thyroidectomy?
No. It is not effective.
1 mg of prednisone is how many mg of hydrocortisone?
4 mg
1 mg of dexamethasone is how many mg of hydrocortisone?
25 mg
What happens to 1,25 OH-vit D in sarcoidosis?
It increases.
Which thionamide causes agranulocytosis?
Methimazole and propylthiouracil both do.
What is the genetic defect in familial dysbetalipoproteinemia?
Presence of two apo E2 alleles.
What is the mechanism of action of spironolactone?
Competitive binding of receptors at the aldosterone-dependent sodium-potassium exchange site in the distal convoluted renal tubule
How long does a patient need to be off spironolactone to screen for primary hyperaldosteronism?
4 - 6 weeks.
What are the porphyrias?
Metabolic disorders caused by the deficiency of enzymes involved in the 8 steps of heme synthesis.
What is the half life of free T3
3.5 days
What happens to the aldosterone level when a patient is on spironolactone?
Aldosterone increases.
What happens to the renin level when a patient is on spironolactone?
The renin level increases.
How long do hypothyroidism symptoms take to disappear after starting treatment?
A few days - as the free T3 and free T4 begin to normalize then the symptoms of hypothyroidism disappear.
What is Wilson’s syndrome?
Alternative medicine diagnosis not accepted by ATA. Decreased conversion of T4 to T3 resulting in subnormal temperatures; treated with sustained release tri-iodothyronine.
What’s the difference between NPH and regular insulin when looking at it?
NPH is cloudy and regular is clear. Any insulin with NPH is cloudy.
What’s the dose of sodium thiosulfate for calciphylaxis?
Initial dose 12.5 g dissolved in 100 ml of normal saline given over the last 30 - 60 minutes of dialysis. Followed by 25 g (two vials) dissolved in 100 ml normal saline with each dialysis session.
What should the calcium x phosphorus product be maintained at in calciphylaxis?
55 mg2/dL2 or less.
What kind of vasculitis is associated with PTU?
ANCA positive vasculitis.
How would you monitor the levothyroxine dose in a patient with panhypopituitarism?
Free T4 level
Where is IGF-1 released from?
Liver
What dosage forms does injectable testosterone come in?
200 mg/ml Comes in 1 ml and 10 ml vials.
What do you replace growth hormone with?
Somatropin.
If a patient has a COPD exacerbation what treatment could cause an abnormal TSH?
Steroids.
What do steroids do to TSH?
Suppress it.
If you have an iodinated contrast allergy can you get radioactive iodine ablation?
Yes. We eat iodine all the time in food. The oral radioactive iodine should not cause the same allergic response.
If someone has hyperthyroidism and is on medication and develops vasculitis what should you think of?
p-ANCA associated vasculitis secondary to the PTU. Not enough data to support association between methimazole and ANCA positive vasculitis.
If a patient has positive thyroid antibodies should you treat them with steroids?
No.
When you order ‘bone age’ x-rays what part of the body do you get x-rayed?
Hand and forearm.
Other than medications, what medical conditions are you looking for when you evaluate a patient for high LDL?
- Hypothyroidism - Nephrotic syndrome or kidney leading to nephrotic range proteinuria. - Primary biliary cirrhosis or other causes of obstructive jaundice.
Does Cushing’s cause high LDL?
No
Does high LDL cause fatty liver?
No.
What component of the lipid panel does estrogen raise?
Triglycerides.
In a cosyntropin stimulation test; is the timing of the cortisol rise important or just the magnitude?
Just the magnitude.
When is the replacement dose of 1.6 mcg/kg used for levothyroxine?
When someone is hypothyroid because of thyroidectomy or radioactive iodine ablation and therefore has no thyroid function at all.
What time of day should testosterone be measured?
8 am
What happens to the glucose reading when alcohol is still left on the finger after cleaning and not waiting for it to dry before checking?
Falsely lowered.
What happens to the glucose reading when you don’t completely fill the yellow box with blood on the glucose meter?
Falsely elevated.
How do you calculate someone’s ‘carb ratio’?
500/Total daily dose of insulin
How do you calculate someone’s ‘sensitivity factor’?
1800/total daily insulin dose of that person
What’s the risk of taking fibrates in renal insufficiency?
Increased risk of rhabdomyolysis.
Can the calcium/creatinine ratio be less than 0.01 in patients with primary hyperparathyroidism?
Yes. In about 20% of patients.
What should you think of if someone has minimal fat on extremities and otherwise abdominal fat and Cushingoid appearance?
Lipodystrophy.
What does fish oil do to warfarin?
Potentiates affect of warfarin causing elevated INR. Warfarin dose would have to be adjusted.
What is a physiological dose of hydrocortisone?
20 mg in the morning, and 10 mg in the afternoon.
Cyclobenzoprine and urine metanephrines.
Falsely elevated.
Duloxetine and urine metanephrines.
Falsely elevated.
Venlafaxine and urine metanephrines.
Falsely elevated
What does phenobarbital do to dexamethasone?
Increases the metabolism of dexamethasone.
How long do intra-articular joint steroid injection (kenalog) last (for the purpose of steroid suppression)?
3 months.
If a woman has hirsutism and secondary amenorrhea with isolated testosterone elevation - how high should the testosterone be to be very concerning for testosterone secreting tumor?
200 or higher.
Which HIV medication increases risk of osteoporosis significantly?
Tenofovir
Does subclinical hypothyroidism have an affect on LDL?
Not really. No significant effect in studies.
When should the labs be drawn during a 72 hour fast for evaluation of hypoglycemia?
When the blood glucose is below 60 mg/dl.
What do you usually do to the insulin when a patient goes into labor?
Hold it. Labor uses up all the glucose so insulin may actually make them hypoglycemic.
Which vitamin D level do you use to determine a patient’s vitamin D status?
25-hydroxy vitamin D.
When is a 24-hour urine calcium not helpful in distinguishing primary hyperparathyroidism from familial hypocalciuric hypercalcemia?
If a patient has significant renal impairment or is on medications that effect calcium excretion.
How much NPH is 20 units of glargine equal to?
10 units BID. Because the glargine is released slowly.
How do you mix NPH and regular insulin - which one do you draw up first?
Regular insulin is drawn up first. You don’t want to get the regular insulin cloudy with the NPH.
What does acetaminophen (Tylenol) do to evaluation for pheochromocytoma?
May elevate the plasma metanephrines in general in some assays.
What are the endocrine diseases that can cause hypercalcemia?
Primary hyperparathyroidism Thyrotoxicosis Adrenal insufficiency Pheochromocytoma
What are the endocrine diseases that can cause weight loss?
Uncontrolled diabetes mellitus Thyrotoxicosis Adrenal insufficiency
If a patient brings in a log book with most glucose numbers ending in ‘0’ and ‘5’ then what do you suspect?
That the numbers are made up.
Does the cosyntropin stimulation test have to be done at 8 am?
No. It can be done any time.
Which medication can decrease severity and frequency of attacks in thyrotoxic periodic paralysis?
Propranolol (40 - 120 mg) per day.
What should you be careful of when repleting potassium in a patient with thyrotoxic periodic paralysis?
It needs to be done slowly and carefully to avoid rebound hyperkalemia.
What do you give before levothyroxine in myxema coma?
Dexamethasone.
What does carvedilol do to glycemic control?
Increases insulin sensitivity.
What happens to the glycemic effects of carvedilol in the presence of ACE inhibitors?
The effect is blunted and they don’t have insulin sensitivity.
Is carvedilol’s effect on insulin sensitivity long term?
No it is not. This has been shown in heart failure trials.
How long before a nuclear medicine radioactive iodine uptake scan does the methimazole need to be stopped?
5 days.
What do you need to make sure of in empty sella syndrome?
That there is no deficiency of pituitary hormones.
The higher the uptake of radioactive iodine on a thyroid scan, the _____ the dose of radioactive iodine required for ablation.
Lower
What’s the target for prolactin levels for a patient with a prolactinoma being treated with dopamine agonists?
Suppress the prolactin to at least 20 ng/ml, and hope the prolactinoma shrinks.
Why is it not advisable to run dextrose through a permacath in a hypoglycemic patient?
Because that would increase risk of infection.
Blood glucose target 2 hours after meals?
40 - 80 units higher than pre-meal readings.
When you have a plan to do a sestimibi scan and an US neck at the same time, what will the radiologist prefer to do first and why?
Sestimibi scan - because it will light up (if positive) and they will know where on the ultrasonogram to look for the adenoma.
Which enzyme does PTH act on to convert 25-hydroxycholecalciferol to 1,25-dihydroxycholecalciferol?
1-alpha-hydroxylase.
What should the posterior pituitary look like on a normal contrast MRI?
It will light up.
Can you get galactorrhea with a slightly high prolactin?
Yes
Should you make dose adjustments based on free T4 in patients with panhypopituitarism even if the dose of levothyroxine was changed recently i.e. A week or two ago.
Yes. Free T4 levels can change in a few days to a week or so.
At what age is it safe to start statins?
10 years.
What treatment options are available for homozygous familial hypercholestrolemia?
LDL apheresis MTP (microsomal triglyceride transfer protein) inhibitor. Apo B-100 inhibitor.
Name the MTP inhibitor recently approved for homozygous familial hypercholestrolemia.
Lomitapide.
Name the apo B-100 synthesis inhibitor recently approved for homozygous familial hypercholestrolemia.
Mipomerson.
How many months supply of testosterone can you prescribe at a time?
6 months.
What are the two main side effects of lomitapide?
GI side effects Hepatoxicity
What fruit can increase lactation?
Papaya
What fruit can cause an abortion in the first trimester of pregnancy?
Papaya
How much elemental calcium does one tablet of 750 mg TUMS contain?
300 mg.
How high does TSH need to be to do radioactive ablation of thyroid cancer?
Above 30.
How many milligrams of calcium carbonate do regular TUMS contain?
500 mg
How many milligrams of elemental calcium do regular TUMS contain?
200 mg
What happens to 1,25 OH vitamin D in primary hyperparathyroidism?
Increases.
What do thiazide diuretics do to urinary calcium excretion?
Decrease it.
When urinary sodium is high what is usually the cause?
Excess sodium in diet.
Why do you check a pH with ionized calcium?
As a safety measure to see if the sample was collected appropriately. If the pH has changed that may mean that the sample was not put on ice immediately and is therefore inaccurate.
Which form of DDAVP gives a more reliable level in the blood in outpatients?
Nasal spray.
Can you give NPH/reg 70/30 mix every 6 hours in patients on continuous tube feeds?
Yes
Can you give NPH every 6 hours to patients on continuous tube feeds?
Yes.
If someone already had atrial fibrillation along with hypothyroidism - should making them euthyroid have any impact on their heart rate?
Not theoretically.
Has metformin been shown to decrease progression to overt diabetes mellitus in patients with pre-diabetes?
Yes
What other electrolyte (besides calcium) can fall after palmidronate treatment of hypercalcemia of malignancy?
Magnesium.
How can gabapentin make diabetes mellitus worse?
By increasing appetite and therefore making you gain weight.
Do you have to give levothyroxine in one big dose in myxedema coma?
You don’t have to. You can give half a dose, wait and see how the patient tolerates it and then give the rest.
How high does the blood glucose have to be on the meter for it to read ‘high’?
Above 550 - 600 mg/dl.
How often should an insulin infusion set be changed out when patient is in an insulin pump?
Every 3 days.
How high does the 24-hour urine sodium need to be to indicate that adequate salt loading was done when testing for hyperaldosteronism?
Over 200 mmol/24 hours
Name two tests you need to do putting the tube on ice immediately after collection?
- ACTH 2. Ionized calcium
What’s the difference between Cushing’s disease and syndrome?
Cushing’s disease is when the pituitary is secreting too much ACTH. Cushing’s syndrome is when there is a source of excess steroids producing Cushingoid features.
What is the maximum age the FRAX calculator calculates fracture risk for?
90 years.
What dose of pamidronate has been shown to effectively decrease calcium concentrations in patients presenting with symptomatic hypercalcemia?
90 mg IV infused over 4 hours.
What is the initial dose of calcitonin?
4 IU/kg q12h for 2 - 4 doses.
Can hypothyroidism cause glomerulonephritis?
Yes
Is sodium thiosulfate acidic or alkaline?
Acidic.
How much do bisphosphonates decease fracture risk?
50%
Do you calculate a FRAX score in patients on bisphosphonates?
No. Because the fracture risk will be even lower when on treatment and not accurate.
What does diarrhea do to oxalate levels in the urine?
Increases it.
What does metabolic syndrome do to uric acid levels?
Increases uric acid levels.
How do you know if adequate salt loading has been done when checking 24 hour urine for hyperaldosteronism?
24-hour urine sodium needs to be over 200 meq.
There is only one drug in one country approved for the treatment of pre-diabetes. Name the country and the drug.
Japan. Acarbose.
What are the drugs that increase insulin sensitivity and keep it sustained?
GLP-1 receptors agonists. TZDs
What are the drugs that inhibit glucagon?
DDP 4 inhibitors GLP-1 receptor agonists
What is the only true class of drugs that improves the insulin resistance in the muscles?
TZDs
How fast the does the GLP-1 and GIP level go up when you start eating?
2 minutes. (K and L cells in the stomach secrete the GLP-1 and GIP when coming in contact with food).
Do GLP-1 receptor analogues make you hypoglycemic?
No
What effect does GLP-1 have on gastric emptying?
Delays gastric emptying.
What does diabetes do to gastric emptying?
Increases rate of gastric emptying.
What does GLP-1 do to food intake?
Decreases it.
Why does Bydureon last longer in the body than Byetta?
Extended release exenetide is given in higher doses and contained in little microspheres that are slowly released and therefore last longer.
How long does Bydureon take to reach steady state in the body?
8 weeks.
Should patients with mostly post-prandial hyperglycemia be on Byetta or Bydureon?
Byetta
Why are exenetide and liraglutide started at lower doses and then moved up?
Because they cause nausea. Once you get through the GI side effects you can increase the dose.
What does prolonged heparin use do to bone mineral density?
Decreases it.
What mutations that can cause bilateral pheochromocytomas.
RET VHL SDHD SDHB TMEM127
Has warfarin been shown to decrease bone mineral density?
There is no concrete evidence.
How do you convert IV hydrocortisone to PO hydrocortisone?
It’s a 1:1 ratio.
What is the urine pH in renal tubular acidosis type 4?
Less than 5.5.
What usually happens to potassium in hyporeninemic hypoaldosteronism?
It is elevated.
What kind of calcium increases the risk of kidney stones?
Calcium carbonate.
What should you look for in adult patients developing lanugo hair all over body?
Cancer. Any kind - usually solid tumor.
Which criteria does the endocrine society recommend for diagnosis of PCOS?
Rotternham criteria.
What should you worry about if the DHEA-S is more than 700?
Adrenal tumor.
Does medullary thyroid cancer respond to radioactive iodine?
No
What should happen to the cortisol if the patient is on vasopressors?
No data to show what happens.
What does the insulin on board feature on a pump do and what is it typically set at?
Prevents insulin stacking. 3 - 4 hours.
If gonads are in the inguinal canal what are they usually?
Testes.
What do ACEI and ARBs do to renin?
Elevate it.
What is the physiologic dose of hydrocortisone?
20 mg in the morning and 10 mg in the afternoon.
What kind of imaging is best to see thyroid nodules?
Ultrasonography.
How long before radioactive iodine ablation does the methimazole need to be stopped?
5 - 7 days.
How long after radioactive iodine ablation should a patient have a separate bathroom and room to avoid radiation exposure to contacts or children?
2 - 3 days.
How far away should a patient who underwent radioactive ablation stay from close contacts to avoid radiation exposure?
6 feet.
What are the maximum number of units you can inject with the Novo Nordisk Flexpen at one time?
60 units.
What is the maximum number of units you can inject with the Novo Nordisk Flexpen at one time?
60 units.
How do you tell which adrenal the aldosterone is coming from in hyperaldosteronism?
Adrenal venous sampling.
What happens to insulin requirements gradually as pregnancy progresses?
Insulin requirements increase.
What happens to insulin requirements immediately after the third trimester of pregnancy?
They go down and then go back up again.
How many pens do you get in a box of Novo Nordisk Flexpens?
5 pens per box.
The 70:30 Flexpen should not be used when there are less than ___ units of insulin in the pen.
12 units
How long do you have to keep the needle in when injecting with the Novo Nordisk Flexpen?
6 seconds.
What pen can you use if you want to inject 0.5 units of insulin e.g. in pediatric or elderly patients?
Novopen 3 Novopen Junior
What volume of liraglutide is present in a Victoza pen?
3 ml
How much hydrocortisone is 1 mg of dexamethasone equal to?
25 mg
How many milligrams of liraglutide in a Victoza pen?
18 mg
How many mg/ml of liraglutide in a Victoza pen?
6 mg/ml
If you prescribe 1.2 mg of liraglutide per day then how many pens per box of Victoza will the patient receive?
2 pens/box
If you prescribe 1.8 mg of liraglutide per day then how many pens per box of Victoza will the patient receive?
3 pens/box
What is the size of a Novofine needle?
30 gauge, 1/3 inch.
What is the size of the Novotwist needle?
32 gauge, 1/4 inch.
How do you check if the Flexpen is working okay with a Novofine needle?
Inject 20 units into the cap. It should fill to the plastic ridges coming together.
What size is the safety needle used with Flexpens?
30 gauge, 1/3 inch (8 mm)
What feature of the safety needle used with Flexpens makes it good for institutional use?
Needle has a covering that always stay on and just retracts when actually injecting.
Flexpens usually come in boxes of…
5
The Medtronic Mini Med insulin pump has needle infusion sets in two sizes. What are they?
6 mm 9 mm
Screening for visceral fat clinically is usually done by…
Serial waist circumference screening.
Can you use acetaminophen with continuous glucose monitoring?
No. It interferes with the readings.
What do ACEIs and ARBs do to GFR?
Decrease it.
Target for proteinuria if diabetic patient is on an ACEI/ARB.
Less than 300.
What is the only NIH sponsored study that failed all three of its objectives?
ACCORD
What are the maximum number of units you can inject with the Lantus Solostar Flexpen at one time?
80 Units.
What are the maximum number of units you can inject with the recently approved Levemir Flexpen at one time?
80 units
What is the Accu-Chek Nano by Roche and what does it look like?
Blood Glucose Meter Small, black, rounded corners, contrast screen.
Which blood glucose meter has a good, ‘not very painful’ lancet device per patient reports?
Accu-Chek Nano.
Why is it recommended to check blood glucose in the finger tips and not other sites?
Because blood glucose value change faster in these capillaries and the results are more likely to be accurate,
Is it possible to check blood glucose from blood from sites other than the finger tips?
Yes
When is it okay to check blood glucose from the palm?
When fasting and before meals.
When is it not okay to check blood glucose from the palm?
- Symptoms of hypoglycemia. - Illness - Post-prandial (up to 2 hours) - After exercise - After injecting insulin. - If patient has hypoglycemia unawareness.
Does fludrocortisone have corticosteroid side effects?
No
Why is TSH checked in hypogonadism patients?
Hypothyroidism can cause decreased gonadotropins.
TRH stimulates which two hormones?
TSH Prolactin
What happens to gonadotropins if the prolactin level is too high?
Decreased.
What is the starting dose of Byetta?
5 mcg subcutaneous BID
Can protease inhibitors cause impaired glucose tolerance and diabetes?
Yes
What colors are the dialysate bags for peritoneal dialysis in order of glucose concentration from least concentrated to most concentrated?
Yellow Green Red
Does androgen deprivation therapy have any effect on diabetes mellitus?
It causes weight gain and worsens diabetes control.
Does having diabetes mellitus type 1 have any effect on bone health?
It deceases bone density and increases risk of fractures.
Does diabetes mellitus type 2 have any effect on bone health?
Osteoporosis has now been included as a complication of diabetes.
By what mechanism to TZDs decease bone density?
Problem with production as there is decreased differentiation into osteoblastic cells.
What’s the bone turn-over rate of trabecular bone?
30%
What is the turn over rate of cortical bone?
6%
Do blood glucose meters usually read lower or higher than laboratory values?
Lower
How many blood glucose values can the Accu-Chek Nano store?
500
What forms does Exenatide come in?
- 5 mg dosage pen - 10 mg dosage pen
What is the least amount of time after an iodinated contrast study that you can give a patient radioactive iodine ablation?
4 weeks
Is there such a thing as dangerously low testosterone?
No.
Can hyperprolactinemia cause hypogonadism?
Yes
Can hypogonadism cause erectile dysfunction without causing decreased libido?
Yes
What do adipose cells do to testosterone?
Aromatize testosterone into estradiol.
What is the triple phase response after pituitary surgery?
First phase: acute diabetes insipidus (4 - 7 days). Second phase: SIADH (transient) Third phase: permanent central diabetes insipidus.
What HbA1c does an average blood glucose of approximately 300 mg/dl correspond to?
12%
What blood glucose does the ADA recommend before a meal?
70 - 130 mg/dl
What blood glucose does AACE recommend before a meal?
Less than 110 mg/dl
How many good lumber vertebrae are needed to properly read a bone density?
2
What is the conversion ratio from hydrocortisone to cortisol?
1:1 ratio
Describe the saline suppression test protocol.
- Place peripheral IV line. 2. Patient should be on bed rest 30 min prior to first blood draw and for the entire duration of the test. 3. Following labs drawn: renin, aldosterone, electrolytes, BUN, creatinine, 18-hydroxycorticosteroid. 4. Infuse 2 litres of normal saline over 4 hours (500 cc/hr). 5. At 4 hours following labs drawn: renin, aldosterone, electrolytes, 18-hydroxycorticosteroid. 6. After completion remove IV lines and the patient can be discharged.
What are the contra-indications for using PTH for osteoporosis?
- Any malignancy that likes to go to bone. - Paget’s disease. - Secondary PTH from renal disease.
What is the dose for safe daily intake of vitamin D recommended?
800 - 4000 IU/day
What blood glucose does ADA recommend 1 - 2 hours after the start of a meal?
Less than 180 mg/dl
What does AACE recommend the blood glucose to be 2 hours after the start of a meal?
Less than 140 mg/dl
What happens to glucagon levels after roux-en-Y gastric bypass surgery?
Post-prandial hyperglucagonemia.
Do you calculate a FRAX score in someone who has already been on bisphosphonates for sometime in the past but is no longer on them?
No
What does chromium deficiency do to glucose tolerance?
Makes it worse. Chromium deficiency worsens diabetic control.
Will Gemfibrozil lower triglycerides if someone is not eating?
No. It lowers dietary triglycerides.
What do you do to the dose of insulin after delivery of the baby?
Cut the dose in half
What if there is suspicion for thyroid storm but you think that there is some other reason for the symptoms?
Still treat as if the patient has thyroid storm because there is no harm in aggressively treating for a few days.
How long does denosumab last in the system/body?
6 months
What are the three things that indicate a thyroid nodule is malignant?
- Microcalcifications. 2. Size greater than 2 cm. 3. Solid nodule (as opposed to cystic).
Can Graves ophthalmopathy cause color blindness?
Yes. Because of compression of outside fibers of optic nerve.
Does fenofibrate make creatinine go up?
It can. It is thought to be benign as it goes back down if you stop it.
Is 400 mcg of levothtroxine too much?
Not if they need it.
Does it matter what time the testosterone is drawn if someone is on testosterone injections?
No
Testosterone replacement can cause irritability and losing temper more easily. True or false?
True.
What issues do patients with Klinefelter’s syndrome normally die of?
Cardiac problems.
What do positive 21-hydroxylase antibodies tell us?
That the patient has autoimmune adrenal insufficiency.
What effect does hyperthyroidism have on warfarin dosing?
Makes patients more sensitive to it so they need less.
Is pre-albumin a reliable indicator of nutrition in the setting of infection?
No
What’s the chance of getting pregnant if you’ve been trying for 1 month?
25%
How long does a patient need to be on a low iodine diet before radioactive iodine ablation of the thyroid?
10 days in the literature. (1 - 3 weeks depending on clinical practice)
How long do you tell patients to follow radiation precautions after radioactive iodine ablation for thyroid cancer?
48 hours per nuclear medicine department.
What is the reason for hypokalemia in thyrotoxic periodic paralysis?
Potassium shifts into the cell.
How successful is cabergoline in treating acromegaly?
Successful in 10 - 30%
Can you monitor growth hormone levels on pegvisoment (somavert)?
No. They remain high.
Can you monitor growth hormone levels on octeotride when treating acromegaly?
Yes.
Is growth hormone level a good screening test for acromegaly?
No.
Is glucagon present in type 1 diabetes mellitus?
It’s almost always absent.
What happens to the armpit hair in people with Addison’s disease?
Decreases.
What color is the 100 mcg levothyroxine pill?
Yellow.
What color is the 150 mcg levothyroxine pill?
Blue
What color is the 175 mcg levothyroxine pill?
Purple.
How much vitamin D do you need to give to raise the vitamin D level by 1 pg?
100 IU/day
What kind of lipid abnormality can obstructive liver disease cause?
Hypercholestrolemia (elevated LDL)
What happens to the glucose concentration in the hepatic portal vein after Roux-en-Y gastric bypass surgery?
Increases.
What do the glucose sensors in the portal vein cause when there is a high glucose concentration in the portal vein?
- Increase hepatic glucose uptake causing the uptake at other sites to decrease. 2. Increase islet cell hormone secretion (more insulin).
What two diagnoses should be excluded in a woman of reproductive age who presents with amenorrhea and galactorrhea?
- Pregnancy 2. Hypothyroidism
What happens to the pituitary gland in pregnancy?
It enlarges.
If a woman of reproductive age has mild hyperprolactinemia; what should you exclude before imaging the pituitary?
- Pregnancy 2. Hypothyroidism
What happens to the alpha-subunit levels in pregnancy?
They are elevated.
What effect does estrogen have on thyroid binding globulins?
Increases the liver synthesis of TBG.
What happens to the levels of TBG (thyroid binding globulins) during pregnancy?
The levels increase.
Why can pregnancy make a patient mildly hypothyroid even though she’s taking the same dose of levothyroxine that kept her euthyroid before pregnancy?
Because of increased TBG (thyroid binding globulin).
How does primary hypothyroidism lead to hyperprolactinemia?
Primary hypothyroidism causes increased secretion of TRH from the hypothalamus that stimulates both TSH and Prolactin (and causes thyrotrope and lactotrope hyperplasia leading to pituitary enlargement).
What happens to the bony epiphyses in congenital adrenal hyperplasia?
There is premature closure.
What percentage of women presenting with hyperandrogenism have congenital adrenal hyperplasia?
2 - 4%
How can you restore normal ovulation in women with non-classical congenital adrenal hyperplasia?
Corticosteroid therapy.
How can you exclude a diagnosis of non-classical congenital adrenal hyperplasia?
An early morning basal 17-OH progesterone value of less than 200 ng/dl.
Are multiple cysts seen in the ovaries on pelvic ultrasound diagnostic of polycystic ovarian syndrome?
No. They are common with multiple etiologies of androgen excess. And also found in 25% woman will normal periods.
Treatment of severe premenstrual syndrome symptoms.
SSRIs. They can be administered daily throughout menstrual cycle or daily during luteal phase only.
What is the treatment of infertility in women with PCOS?
Clomiphene.
What do you think of in a man with hypogonadotrophic hypogonadism and chondrocalcinosis?
Hemochromatosis.
What is a common cause of male infertility in Pakistan?
Testicular tuberculosis.
Which gene is affected in X-linked Kallman Syndrome?
Deletions in the KAL1 gene.
What test should be performed in all patients with primary ovarian failure?
Karotype (to rule out Turner Syndrome/ or other forms of gonadal dysgenesis).
Which gene mutations happen in patients with Kallman syndrome and midline abnormalities (colobomas, cleft palate, horseshoe kidney, or renal agenesis) and synkinesia?
KAL1 gene mutations.
What gene mutations are present in patients with Kallman syndrome with cleft palate but not horseshoe kidney, coloboma, or synkinesia?
FGFR1 gene mutation.
What pattern of inheritance does an FGFR1 gene mutation have?
Autosomal (usually dominant)
What kind of inheritance does KAL1 gene mutation have?
X-linked mutation.
What are GPR54 gene mutations associated with?
Congenital hypogonadotropism.
Which hormone is high when you have acanthosis nigricans?
Insulin.
What can cause xanthalasmas in a patient with a non- remarkable lipid panel?
Sitosterolemia.
By how much do triglycerides go up after a fatty meal and how long so they stay up?
20% 4 hours.
What happens to SHBG levels in men with Klinefelter’s syndrome?
They are increased.
Why are SHBG elevated in patients with Klinefelter’s syndrome?
Because of increased estrogen production.
Does radiotherapy of a pituitary tumor shrink it?
No. But in some people’s experience they do shrink. However, they definitely do not shrink quickly (so cannot fix an acute neurological question).
When looking at Hounsfield units for adrenal masses - should the CT be with or without contrast?
Without contrast.
What is a DAX1 (also called NROB1) gene mutation associated with?
Hypogonadotrophic hypogonadism plus primary hypoadrenalism.
Does an adrenal tumor usually cause gynecomastia and isolated estradiol production?
No.
Which syndrome should you suspect in patients with premature ovarian failure who have a family history of mental retardation, autism, or premature ovarian failure?
Fragile X syndrome.
How do you test for fragile X syndrome?
FMR-1 genotyping.
If a young woman has premature menopause (secondary amenorrhea with elevated FSH levels) then what is the most likely cause?
Turner’s syndrome.
Which two tests are important to do in a patient who has been diagnosed with Turner’s syndrome?
- Echocardiography. 2. EKG.
What is the most common side effect of androgen replacement therapy?
Acne.
Can hyperthyroidism cause tender gynecomastia?
Yes.
Does hyperthyroidism cause suppression of gonadotropins?
No.
A well virilized man presents with low libido and tender gynecomastia plus low testosterone, very high estrogen, and suppressed gonadotropin levels. Diagnosis?
Sertoli cell tumor. Leydig cell tumor that makes estradiol.
If post menopausal women take unopposed estrogen for 5 years, what does it significantly increase the risk of?
- Stroke - Cardiovascular disease - Symptomatic cholethiasis - Deep venous thrombosis
Does hormone therapy reduce the risk of osteoporosis-related fractures in post menopausal women?
Yes
How do you test for anovulation?
Serum progesterone of 3 or less on day 20 - 24 of cycle.
Slowly progressive virilization. Diagnosis?
Hyperthecosis ovarii (benign ovarian androgen-producing tumors).
What does the absence of fructose in the seminal fluid suggest?
Obstruction distal to the seminal vesicles.
In what conditions do you see high serum testosterone levels with low gonadotropin levels?
- hCG-producing tumors. - hCG abuse. - testosterone abuse. - androgen-secreting Leydig tumors or adrenal tumors.
What happens to sex hormones in males with thyrotoxicosis?
- high total testosterone. - high total estradiol. - high SHBG levels. - lowish free testosterone levels. - lowish free testosterone to free estradiol levels.
Is a history of deep venous thrombosis an absolute contraindication to all oral estrogen-progesterone contraceptive use?
Yes
Do non-oral progesterone-only contraceptives increase the risk of thromboembolism?
No.
How often does amenorrhea occur in patients taking OCPs?
5 - 10%
What is macroprolactinemia?
High molecular mass prolactin with little to no bioactivity.
How common is macroprolactinemia?
About 20%.
What is the first line treatment for hirsutism in a patient with polycystic ovarian syndrome?
Oral contraceptives.
What should you give a pre-menopausal age woman with amenorrhea secondary to hyperprolactinemia?
Low dose oral contraceptive pills.
Patient presenting with delayed puberty, hypogonadotrophic hypogonadism, with history of vague abdominal complaints and skin hyperpigmentation. Diagnosis?
Adrenal hypoplasia congentina (X-linked recessive disorder).
What percentage of Grave’s disease patients have Grave’s ophthalmopathy?
25%
What are the extra thyroidal manifestations of Grave’s disease?
- Grave’s ophthalomopathy. - Thyroid dermopathy. - Thyroid acropachy.
What percentage of patients with hyperthyroidism have normal serum levels of free T4 but elevated levels of free T3 (T3 thyrotoxicosis)?
2 - 4 %
What tests should you order for initial assessment of a patient you suspect of having hyperthyroidism?
- TSH - Free T4 - Free T3
Which antibody is specific for Grave’s disease?
TSH receptor antibody (TRAb). 98.3% sensitivity; 99.2% specificity. (thyroglobulin stimulating antibody).
In hyperthyroid patients, what is the diagnosis of Grave’s disease usually based on?
- Anti-TSH-receptor antibody assays. - Thyroid ultrasonography.
Does the addition of cholestyramine together with propylthiouracil accelerate the decline in serum levels of thyroid hormones?
Yes
Is the dose-response relationship clearer with propylthiouracil or methimazole?
Propylthiouracil.
What is the incidence agranulocytosis in patients treated with methimazole?
0.1 - 0.5%
Can radioactive iodine ablation worsen hyperthyroidism symptoms?
Yes, by causing destructive thyroiditis.
Pre-treatment with which anti-thyroid medication introduces a greater degree of resistance to iodine ablation?
Propylthiouracil.
Is there increased incidence of cancer with radioactive iodine ablation treatment?
Most studies have showed no association.
What agent causes the largest increase in lumbar spine BMD?
Daily injections of PTH 1-34 (teriparatide)
In what way can a combination of drugs be used to achieve greatest increase in bone mineral density?
Sequentionally, with 12 months of PTH, followed by 12 months of alendronate.
Does BMD decline after the discontinuation of PTH 1-34?
Yes.
A patient has severe bone pain, occasional fractures or pseudo fractures, hypophosphatemia, and low/inappropriately decreased serum 1,25-dihydroxyvitamin D levels. Diagnosis?
Tumor-induced osteomalacia.
Patients suspected of having tumor-induced osteomalacia most commonly have increased secretion of which of the following proteins that directly cause hypophosphatemia?
Serum fibroblast growth factor-23 (FGF-23)
What effect do thiazides diuretics have in urinary calcium?
They decrease it.
What effect does decreasing salt intake have on urinary calcium?
Decreases it.
To avoid formation of stones, should the urinary citrate be high or low?
High.
How does 1,25(OH)2 vitamin D increase calcium?
By stimulating intestinal calcium absorption.
Fibrous dysphasia in McCune Albright syndrome is associated with a mutation in the GNAS gene leading to reduction in expression of which protein by 50%?
Gs-alpha.
Can inhaled corticosteroids cause Cushing’s syndrome?
They can; but very rarely.
If a patient has variable thyroid hormones levels on amiodarone then would be more likely to have underlying thyroid disease. True or false?
True.
Does calcitriol come in mg or mcg?
mcg
What does cyclosporine do to cholesterol?
Raises the LDL cholesterol.
What is the lipid lowering therapy that is most hepatotoxic?
Niacin.
What do tomatoes do to adiponcetin levels?
Raise them.
Who has higher cortisol levels… Obese children or normal weight children?
Obese children.
What does sleep deprivation do to morning ghrelin levels?
Increases them.
What do steroids do to potassium?
They make it lower.
Should you give radioactive iodine to a patient who’s actively vomiting?
No. Because they might contaminate the people around them if they vomit.
What should you think of in a patient with a relatively unremarkable lipid panel and xanthalasmas?
Sitosterolemia
What do proton pump inhibitors do to gastrin level?
Raise it.
What does gastrin do to insulin levels?
Gastrin stimulates insulin.
What do proton pump inhibitors do to chromogranin A?
Increase the levels.
What does octeotride do to gastrin?
Inhibits it.
What does 1,25 OH vitamin D do to the phosphorus levels?
Increases it (because of increased intestinal absorption)
What’s the half life of I-131 radioactive?
8 days
What is the mechanism of action of abiraterone?
17 alpha-hydroxylase inhibitor.
What drug can you use in refractory prostate cancer (hint: similar to giving patient CAH).
Abiraterone.
What effect does amiodarone have on T4 to T3 conversion?
Decreases conversion - so T3 levels are typically lower and T4 values are higher.
What does amiodarone normally do to thyroid function tests?
TSH usually goes up then starts coming down again but can go anywhere. Free T3 usually goes down. Free T4 usually goes up.
1 year mortality in women with osteoporotic fractures?
17 - 22 %
1 year mortality in men with osteoporotic fracture?
31 - 35%
Genetic and acquired bone disorders with hypophosphatemia require high dose phosphate replacement and what other medication?
Calcitriol
Which gene mutations can lead to stimulation of the W nt/beta-careening signaling pathway in osteoblasts leading to increased bone formation/high bone mass prototype?
Activating mutations of the LRP5 gene.
What happens to the PTH level in chronic magnesium deficiency?
PTH secretion is impaired. Levels may be low or inappropriately normal for degree of hypocalcemia.
A patient has: primary hyperparathyroidism, ossifying fibromas of the mandible and maxilla, renal/uterine tumors. Diagnoses?
Hyperparathyroidism-jaw tumor syndrome.
How is hyperparathyroidism-jaw tumor syndrome inherited?
Autosomal dominant.
A mutation in which gene causes hyperparathyroidism-jaw tumor syndrome?
Germline mutation of the HRPT2 gene.
What is humoral hypercalcemia of malignancy due to?
Over-production of PTH-related peptide by tumor cells.
What is the common initiating insult predisposing to tissue injury in diabetes?
Endothelial dysfunction.
Can people with prolactin secreting macroadenomas come off the dopamine agonists?
Sometimes; but usually not.
What can you consider if the prolactinoma is not shrinking despite therapy?
It could be co-secreting IGF-1.
What effect does hypothyroidism have on peripheral resistance?
Increased peripheral resistance.
Can a patient be hypothyroid and tachycardic with increased diastolic pressure?
Yes. Increased peripheral resistance can cause paradoxical tachycardia and elevated diastolic blood pressure.
What are the two stimuli for high vitamin 1,25 OH-D?
Increased PTH. Low phosphate.
Which cells are adipocytes and osteoblasts derived from?
Pluripotent stromal cells
What effect does rosiglitazone have on adipocyte genesis?
Increases it.
What does rosiglitazone do to osteoblast genesis?
Decreases it.
What is lorcaserin?
Serotonin 2c receptor agonist. (Weight loss drug)
What does Qsymia contain?
Phentermine/topiramate
Does increased visceral fat increase fracture risk?
Yes
What comorbidities have been found to increase the risk of osteonecrosis of the jaw?
Dentoalveolar surgery - dental extraction. Local dental suppuration (associated with dental infection) Periodontal disease. Radiation therapy to the affected jaw site. Systemic steroid therapy.
What happens to serum total calcium levels during pregnancy?
Typically decrease.
What happens to PTH levels during pregnancy?
Typically increase.
What happens to the bone mineral density at trabecular sites during lactation?
BMD may decrease by 3 - 10%.
Does decrease in BMD at trabecular sites reverse after completion of lactation?
Yes
Can you be resistant to levothyroxine?
Yes
What should you do if the TSH is low (borderline), the free T4 is in the low half of normal and the free T3 is normal?
Check other pituitary hormones to see if patient might have central hypothyroidism with other hormone deficiencies.
What are The Endocrine Society’s guidelines on diabetes screening in pregnant women?
Recommend screening with fasting blood glucose, HBA1c or random plasma glucose at first prenatal visit. Agree with USPSTF recommendation of screening for gestational diabetes at 24 - 28 weeks.
Is a diabetic’s spouse at increased risk of developing diabetes mellitus?
A study showed increased risk of developing diabetes. This may be because of shared environmental factors.
By how much can intensive lifestyle modification decrease the risk of diabetes?
Up to 58%
Which ethnic/racial group does not have an increased risk of developing diabetes?
Indigenous Alaskans
Which Asian subgroup has the highest incidence of thyroid cancer?
Filipinos.
Which racial group (blacks or whites) are more likely to develop diabetic end-stage renal disease?
Blacks are 3 times more likely to develop ESRD compared to whites.
Inactive pulmonary tuberculous takes up radioactive iodide. True or false?
True
General recommendations for blood glucose values in pregnancy?
Before meals: Less than or equal to 90 mg/dl. One hour after the start of meal: Less than or equal to 140 mg/dl. Two hours after the start of meal: Less than or equal to 120 mg/dl.
What are the functions of PTH-rp in pregnancy?
- Contributes to increased maternal serum 1,25-dihydroxyvitamin D levels. 2. Helps regulate placental calcium transport. 3. Involved in calcium transfer to breast milk.
Biochemical signs of hypoparathyroidism (low calcium, high phosphorus) with elevated PTH. Diagnosis?
Pseudohypoparathyroidism characterized by end organ unresponsiveness to PTH.
Which ethnic/racial group has the highest obesity rate amongst adolescent girls?
Black adolescent girls (29%)
Which ethnicity/racial group has the highest obesity rates amongst adolescent boys?
Mexican American adolescent boys (27%)
What does the D2 indicate on the vitamin D panel?
The vitamin D coming from the diet.
How long does it take type 1 diabetics to develop nephropathy?
About 15 - 20 years.
If a patient presents with a eruptive rash a few weeks after starting mirtazapine what should you think for?
Think of eruptive xanthomas from hypertriglyceridemia as mirtazapine can cause elevated triglycerides.
How would you treat severe osteoporosis in a patient with chronic kidney disease stage 4?
Denosumab
Thalessemia increases risk for osteoporosis. True or false?
True
Does hyperglycemia really cause pseudo-hyponatremia?
If you directly measure the sodium it will really be low.
Name two monoclonal antibodies against PCSK9.
Alirocumab Evolocumab
Which ethnic group are PCSK9 mutations more common in?
Blacks (Africans)
Apo lipoprotein (little) a. Treatment?
Niacin
Excess of which two vitamins can cause hypercalcemia?
Vitamin D Vitamin A
Which osteoporosis medication is a good choice in renal failure?
Denosumab.
The thicker the bone the stronger it is. True or false?
Generally true
In women with osteopenia the pores in the bone are an important determinant of fracture risk. True or false?
Has been shown to be true.
Are the osteoclasts more active in osteoporosis or osteoblasts?
Osteoclasts.
If there is greater differentiation to adipocytes instead of osteoblasts there is increased fracture risk. True or false?
True
What’s the receptor on osteoblasts?
RANK
What factors are released from the bone when osteoclasts escort bone?
IGF-1 TGF-1
What happens when you knock out RANK or RANKL in mice?
Causes osteopetrosis.
Odanacatib. What is it?
Cathepsin K inhibitor
Do cathepsin K inhibitors alter bone formation.
No
What are romosozumab and blosozumab?
Humanised monoclonal antibody blocking sclerostin.
Do blacks have denser bones.
Yes
What is the female athlete triad?
Anenorrhea Eating disorders (low energy availability) Osteoporosis
What does depo-provera do to estrogen levels?
Decreases estrogen level
Can you regain bone mass after depo-provera or pregnancy?
Yes
What does estrogen do to vitamin D?
Enhances availability
What do fibers and oxalate in vegetables do to calcium?
Increase binding and decrease absorption of calcium.
What does high salt intake do to calcium excretion?
Increases calcium excretion
Is magnesium recommended for bone health?
Not really
Can strontium be used to treat osteoporosis?
It is approved in Europe but being reviewed because of side effects. Only strontium ranelate is approved in Europe.
Is the effect of smoking on osteoporosis reversible if they quit smoking?
Yes
Is the FRAX estimate still accurate if the femoral neck and spine t-scores are very different?
It may over- or under-estimate if the spine differs from the femoral neck by more than 1 standard deviation.
What happens to the fracture risk probability when the prednisone dose is less than 2.5 mg per day?
Over-estimated.
What happens the fracture risk calculated when the prednisone dose is more than 7.5 mg per day?
Under-estimated.
Which bone turnover markers are measured to see bone turnover in osteoporosis?
Serum CTX Urine NTX
What is the mechanism of action of denosumab?
RANKL inhibitor
What is the incidence of osteonecrosis of the jaw on high dose IV bisphosphonates (doses used in malignancy)?
1 - 10%
What’s the dose of teriparatide (Forteo)?
20 mcg S/C per day for a maximum of 2 years (24 months).
Does renal disease increase your risk of dying?
Yes
Does calcium carbonate need food to be absorbed?
Yes
Why is calcium carbonate taken with food?
Because it needs gastric acid to be absorbed.
Does calcium citrate need to be taken with food?
No. Does not need gastric acid to be absorbed.
Which is more potent: alendronate or risedronate?
Risedronate.
If you notice worsening creatinine in a hyperlipidemia/hypercholestrolemia patient then which medication should you start suspecting?
Fenofibrate
Which hormone deficiencies keep the bones immature?
Thyroid hormone. Growth hormone.
What is a pituitary microadenoma?
A pituitary tumor that is less than 10 mm in diameter.
What is a pituitary macroadenoma?
A pituitary tumor that is 10 mm or greater in diameter.
40% of growth-hormone secreting adenomas have what kind of mutation?
Activating gsp mutations
Which gene mutations have been identified in metastatic pituitary carcinomas?
H-ras gene mutations.
Which gene is common in all pituitary types (especially prolactinomas)?
Pituitary tumor transforming gene.
A truncated form of FGFR-4 is immunodetected in one third of which types of pituitary tumors?
Prolactinomas
What is Carney’s complex characterized by?
- Pituitary adenomas. - Cardiac myxomas. - Schwannomas. - Thyroid adenomas. - Spotty skin pigmentation.
What is the incidence of lactotrophs?
30%
What is the incidence of somatotrophs?
15%
What is the incidence of corticotrophs?
15%
What is the incidence of gonadotrophs?
10%
What is the incidence of thyrotrophs?
Less than 1%
What is the incidence of null cell adenomas?
20%
What is a “silent” adenoma?
One that has positive hormone staining but is clinically silent.
What is the incidence of plurihormonal adenomas?
15%
Which plurihormonal (co-secretor) pituitary adenoma is most common?
Growth hormone and prolactin.
A man has decreased libido and impotence with a pituitary adenoma. Diagnosis?
Prolactinoma.
A woman has infertility/abnormal menses, galactorrhea and a pituitary adenoma. Diagnosis?
Prolactinoma
Acromegalic patients have increased mortality related to associated cardiovascular, respiratory, gastrointestinal and metabolic disorders. True or false?
True.
Obesity, hypertension, glucose intolerance/diabetes, hirsutism, gonadal dysfunction, skin thinning/bruising, proximal muscle weakness, psychiatric problems, osteoporosis/necrosis of femoral heads, poor wound healing and frequent superficial fungal infections and pituitary adenoma. Diagnosis?
Cushing’s disease.
What percentage of thyrotrophs are locally invasive?
More than 60%
Macroadenoma presenting with visual disturbances, symptoms of hypopituitarism or headaches. What type of pituitary adenoma is it most likely?
Gonadotroph adenomas.
Which pituitary cells are most commonly affected in hypopituitarism?
Gonadotrophs.
Which pituitary cells are most resistant to mass effects and the last to lose function?
Corticotrophs and thyrotrophs.
Deficiency of which two hormones usually indicates panhypopituitarism?
TSH ACTH
Which pituitary hormone deficiency is the rarest?
Prolactin.
When will you get prolactin deficiency?
When the anterior pituitary is completely destroyed such as in apoplexy.
If a patient has bitemporal hemianopsia, loss of red perception, scotomas and blindness then which way is the pituitary adenoma growing?
Upwards - compressing and putting pressure on the optic chiasm.
If a patient has diplopia, ptosis, ophthalmoplegia, and facial numbness then which way is their pituitary adenoma growing?
Laterally, invading cavernous sinus, leading to lesions of the 3rd, 4th, 6th and ophthalmic branch of 5th cranial nerve.
Which part of the brain needs to be involved for the following disorders: - Diabetes Insipidus - Appetite/behavioral disorders - Sleep and temperature dysregulation
Hypothalamus
If a patient has cerebrospinal fluid rhinorrhea - which way is their pituitary tumor extending?
Inferiorly.
What parts of the brain need to be affected for a pituitary tumor to cause uncinate seizures, personality disorders and anosmia?
Invasion of parasellar mass into frontal and temporal lobes.
Severe headache, neck stiffness, progressive cranial nerve damage, bilateral visual disturbances, change in consciousness, cardiovascular collapse and coma. Diagnosis?
Pituitary apoplexy.
Calcified, cystic, suprasellar tumors arising from embryonic squamous cell rests of Rathke’s cleft. Diagnosis?
Craniopharyngioma.
What age groups do craniopharyngiomas have the highest incidence in?
Bimodal peak of incidence: 1. 5 - 10 years of age. 2. Late middle age.
Do Rathke’s cleft cysts have a low or high recurrence rate after partial excision?
Low.
What are the most common hormonal abnormalities in pituitary granulomas like sarcoidosis?
- Hypogonadotrophic hypogonadism - Mild hyperprolactinemia - Diabetes insipidus
Where in the brain does sarcoidosis have a predilection for?
- Hypothalamus - Posterior pituitary - Cranial nerves
Which disease is characterized by infiltration of dendritic cells?
Langerhans’ histiocytosis.
Which endocrine disorder is Langerhans’ cell histiocytosis associated with?
Diabetes Insipidus
What percentage of patients with Langerhans’ cell histiocytosis get anterior pituitary dysfunction?
20%
Triad of diabetes insipidus, exophthalmos and lytic bone disease. Other features: axillary skin rash and a history of recurrent pneumothorax. Diagnosis?
Hand-Schuller-Christian disease.
What do children with Hand-Schuller-Christian disease usually present with?
Growth retardation and anterior pituitary hormone deficits.
What are the MRI brain findings in a patient with Langerhans’ cell histiocytosis?
Thickened pituitary stalk or diminished posterior pituitary bright spot, and possibly bone lesions.
Focal or diffuse infiltration of the pituitary by inflammatory cells is called…
Hypophysitis.
Who usually gets lymphocytic hypophysitis?
Women in late pregnancy or during the post-partum period.
How do you confirm a diagnosis of lymphocytic hypophysitis?
By histology or resolution of mass over time.
Can partial recovery of pituitary function and resolution of sellar mass occur spontaneously in lymphocytic hypophysitis?
Yes
Can partial recovery of pituitary function and resolution of the sellar mass occur in lymphocytic hypophysitis with use of corticosteroids and hormone replacement?
Yes
Is granulomatous hypophysitis associated with pregnancy?
No
What does the histology show in granulomatous hypophysitis?
Chronic inflammation and granulomas.
What changes can pregnancy cause in the pituitary?
Lactotroph hyperplasia.
What changes does long-standing hypothyroidism cause in the pituitary?
Thyrotroph hyperplasia.
What changes in the pituitary does long-standing primary hypogonadism cause?
Gonadotroph hyperplasia.
What pituitary changes does the ectopic secretion of growth hormone-releasing hormone cause?
Somatotroph hyperplasia. (Very rare)
Which cancers most commonly metastatize to the pituitary?
Breast cancer Lung cancer
How is the diagnosis of pituitary carcinoma established?
It can only be established when the lesion metastatizes.
In prolactinomas is the serum prolactin usually proportional to the tumor mass?
Yes
Macroprolactinomas usually have a prolactin level of…
> 250 ng/mL
What is the differential diagnosis of hyperprolactinemia between 20 - 200 ng/mL?
- Microprolactinomas. - Stalk compression from a sellar masse. - Medication induced hyperprolactinemia. - Due to ‘hook effect’.
How do you confirm a diagnosis of acromegaly?
Elevated IGF-1 levels. Failure to suppress GH during oral glucose tolerance test.
What are the screening tests for Cushing’s disease?
- 24-hour urine free cortisol. - Low-dose dexamethasone suppression test. - Late-night salivary cortisol.
Differential if the ACTH is elevated in the setting of biochemically confirmed Cushing’s syndrome?
Cushing’s disease (pituitary source). Ectopic ACTH syndrome.
How do you differentiate between Cushing’s disease and ectopic ACTH syndrome?
- High-dose dexamethasone suppression test - Inferior petrosal sinus sampling.
Can the PTH be high in someone with bone metastasis?
Yes
What should you think of when there are elevated thyroid hormone levels in the setting of an elevated of inappropriately normal TSH?
TSH-secreting adenomas
Which pituitary adenoma can you find an elevated pituitary glycoprotein hormone alpha-subunit (Alpha-GSU) in?
TSH secreting adenoma
How can you differentiate between a TSH-secreting adenoma and thyroid hormone resistance syndromes?
T3 suppression TRH stimulation
Are gonadotroph adenomas usually functioning or non-functioning?
Non-functioning
How often do elevations of LH and FSH occur in gonadotroph adenomas and are they clinically significant?
In minority of patients. Usually not clinically significant.
In what situation can a cosyntropin stimulation test be normal in secondary adrenal insufficiency?
Recent onset corticotropin deficiency; because it takes time for the adrenals to atrophy after acute disruption of ACTH secretion.
What should you follow (by way of monitoring) in secondary hypothyroidism?
Free T4
Can you diagnose growth hormone deficiency by measurement of growth hormone?
No. Baseline growth hormone values do not distinguish reliably between normal and subnormal GH secretion.
How do you confirm a diagnosis of growth hormone deficiency?
GHRH-arginine stimulation test. Insulin tolerance test.
Secondary hypogonadism may be secondary to hyperprolactinemia. True or false?
True.
Which hormones need to be checked in women with abnormal periods?
FSH/LH Estradiol Prolactin
Should macroadenomas found as pituitary incidentalomas be screened for hypersecretion or hypopituitarism?
Both
Should microadenomas found as pituitary incidentalomas be screened for hypersecretion or hypopituitarism?
Hypersecretion
What percentage of pituitary microadenomas grow if they are not treated?
10%
What percentage of pituitary macroadenomas grow if not treated?
24%
Contiguous sections of pituitary MRI can detect lesions how big?
1 - 3 mm
How much gadolinium to pituitary tumors take up compared to other brain structures?
Less than normal pituitary tissue but more than the rest of the CNS.
Which images on pituitary MRI are used for diagnosing high-signal hemorrhage?
T2-weighted images
What should the maximum diameter of the pituitary gland be in pregnancy?
12 mm
What are the indications for pituitary adenoma surgery?
- Non-functioning macroadenomas. - GH-, TSH-, or ACTH-secreting adenomas. - Progressive compressive features leading to: visual compromise, hypopituitarism, other CNS dysfunction. - Hemorrhage (especially with sudden visual field compromise). - Intolerant to resistant to medical therapy.
What is the procedure of choice for surgical resection of most pituitary tumors?
Transsphenoidal microsurgical approach is the procedure of choice for more for more than 90% of pituitary tumors.
What are the most common transient complications of pituitary resection?
- Diabetes Insipidus - SIADH - CSF leakage
What are the major permanent complications of pituitary surgery?
- Diabetes Insipidus - SIADH - Iatrogenic hypopituitarism - Local damage
What are the indications for pituitary irradiation?
- Large tumors with incomplete resection. - Patients with contra-indications to surgery.
What kind of radiotherapy is best for pituitary adenomas?
Gamma knife: delivers high-dose radiation to the tumor while sparing surrounding tissue.
What are the complications of radiotherapy?
- Hypopituitarism (develops in up to 80% of patients after 10 years). - Optic nerve damage. - Brain necrosis.
What class of drugs are first line therapy for prolactinomas?
Dopamine agonists.
Is cabergoline or bromocriptine longer-acting?
Cabergoline
What class of drugs are used to treat acromegaly?
Somatostatin analogs. These can be used in combination with dopamine agonists. Growth hormone receptor antagonists.
Name two somatostatin analogs?
- Octeotride (Sandostatin) - Lanreotide (Somatuline)
What is the medical therapy (class of drugs) for TSH-secreting pituitary adenomas?
Somatostatin analogs
Name a growth hormone receptor antagonist.
Pegvisomant.
Levels of which hormone do you need to monitor when patient is on Pegvisomant?
IGF-1
Name an oral chemotherapy agent that has been used in aggressive pituitary tumors.
Temozolomide.
Name two drugs that can used to inhibit cortisol synthesis?
Ketoconazole Metyrapone
Which anti-neoplastic drug can be used to achieve biochemical control in Cushing’s disease?
Mitotane.
How long after pituitary surgery should patients be evaluated for complete tumor resection and hormone dysfunction?
4 - 6 weeks
Why is follow-up necessary after pituitary irradiation?
- Response to therapy may be delayed. - Incidence of hypopituitarism increases with time.
When are follow-up MRIs needed after pituitary surgery?
In patients with persistent or recurrent disease.
Where do malignant prolactinomas typically metastatize to?
Bone, lymph nodes, lung, liver or spinal cord.
Do microprolactinomas occur more frequently in women or men?
20 times more common in women.
Do macroprolactinomas occur more frequently in women or men?
Equally common
What is the most frequent pituitary tumor occurring in multiple endocrine neoplasia syndrome?
Prolactinoma
Which other hormonal deficiencies caused by a macroprolactinoma are usually reversible?
Hypogonadism (LH and FSH is inhibited by prolactin).
Which other hormone deficiencies caused by macroprolactinomas are generally not reversible?
Secondary hypothyroidism (TSH) Secondary adrenal insufficiency (ACTH)
What is the first requirement of diagnosis of a prolactinoma?
Persistently elevated prolactin level.
What level of prolactin is usually diagnostic of a prolactinoma?
More than 200 ng/mL
When is a pituitary MRI done in prolactinoma?
Once persistent hyperprolactinemia has been established.
Differential diagnosis of high prolactin levels.
HIGH PROLACTIN Hypothyroidism Idiopathic Glucocorticoid insufficiency Hyperplasia of lactotrophs Physiologic (nipple stimulation or pregnancy) Renal failure Opiates/other drugs (estrogen, anti-psychotics, anti-depressants, anti-hypertensives, antiemetics) Liver failure Adenoma Convulsion Trauma (chest wall) Irradiation/iatrogenic No abnormality (macroprolactinemia)
Why can elevations in prolactin levels be seen in renal and liver failure?
Because of decreased prolactin clearance.
How does adrenal insufficiency (glucocorticoid deficiency) cause elevated prolactin levels?
Glucocorticoids inhibit prolactin gene transcription and release.
How can macroprolactinemia be distinguished from monomeric hyperprolactinemia?
By polyethylene glycol precipitation.
What initial tests should be orders when an elevated prolactin level is found?
- TSH - CMP - Pregnancy test (if pre-menopausal female)
How do you exclude the Hook effect?
Serial dilutions of prolactin in patients with pituitary macroadenoma and mild to moderate prolactin elevation.
Why do you need to distinguish a non-functioning adenoma from a prolactinoma?
Prolactinomas are treated medically and non-functioning adenomas are treated surgically.
Why does the Hook effect occur?
Immunoradiometric assay is used to measure prolactin levels so a falsely low value can occur when a large amount of prolactin saturates the anti-bodies.
All macroprolactinomas require treatment. True or false?
True
All microprolactinomas require treatment. True or false?
False.
When should you treat a microprolactinoma?
- Symptomatic - Rapidly increasing prolactin levels indicative of an enlarging tumor.
What is the target of therapy for macroprolactinomas?
Normal prolactin level
What is the target of therapy for microprolactinoma?
- Restoration of gonadal function. - Relief of symptoms.
What are the doses of bromocriptine typically used in prolactinomas?
2.5 - 20 mg per day (single or BID dose)
In what percentage of cases (of prolactinomas) can bromocriptine reduce prolactin levels to normal?
70 - 90%
How long after treatment of prolactinoma is initiated does it typically take for galactorrhea to resolve?
2 - 3 months.
How can bromocriptine treatment complicate surgical treatment of macroadenomas?
Bromocriptine treatment lasting more than 6 - 12 weeks has been associated with perivascular fibrosis of the tumor, which can complicate complete tumor resection.
What are the most common side effects of bromocriptine?
Nausea and vomiting. Orthostatic hypotension may occur when initiating therapy.
What is the typical dose of cabergoline given in prolactinomas?
0.25 mg - 1 mg twice a week.
Which works better: bromocriptine or cabergoline?
Cabergoline.
Is there any risk of valvular abnormalities with cabergoline?
Higher doses used to treat Parkinson’s disease can cause valvular fibrosis; however at lower doses used to treat prolactinomas there appears to be minimal risk, though randomised studies have not yet been done.
Name a dopamine agonist that has not been approved for use in the US yet.
Quinagolide
What can be done to reduce the risk of potential expansion of macroprolactinoma in a woman desiring pregnancy?
Pituitary surgery aimed at debulking tumor.
When is radiotherapy indicated for a macroprolactinoma?
- Refractory to medical and surgical treatment. - Malignant prolactinoma.
What is the risk of tumor expansion in pregnancy of a microprolactinoma?
Less than 3%
What is the risk of tumor expansion in pregnancy of a macroprolactinoma?
30%
What is the drug of choice for prolactinomas in pregnancy?
Bromocriptine.
Has an increase in fetal adverse events been demonstrated with use of bromocriptine or cabergoline?
No
Why is bromocriptine preferred to cabergoline for treatment of prolactinomas in pregnancy?
Because there is more experience with bromocriptine; and the data on cabergoline is more limited.
How should the bromocriptine dose be titrated in women with microprolactinomas wishing to get pregnant?
To normalize prolactin levels and restore regular menses.
What do you do with the bromocriptine once the patient with the microprolactinoma is pregnant?
Stop bromocriptine as soon as pregnancy is confirmed. (Barrier methods should be used until regular menses is achieved so that pregnancy test can be performed immediately when a cycle is missed).
How should women with macroprolactinomas be treated if they desire pregnancy?
Pre-treatment with bromocriptine for a sufficient period to cause substantial tumor shrinkage in addition to regular menses. If it does not shrink sufficiently then pre-pregnancy transsphenoidal surgical debulking can be considered.
Is there any benefit to monitoring prolactin levels in pregnant patients?
No
What is the treatment of choice for patients with symptomatic prolactinoma enlargement during pregnancy?
Reinstitution of bromocriptine therapy at lowest effective dose during pregnancy. Transsphenoidal surgery or delivery (if pregnancy is far enough advanced) if there is no response to bromocriptine and vision is steadily worsening.
When is tapering of dopamine agonist considered in treatment of prolactinomas?
When the prolactin level has been stable for at least 3 years and the tumor size has decreased significantly. These patients still require close follow-up to monitor for hyperprolactinemia and tumor growth.
What is the incidence of acromegaly?
3 cases per million per year.
Where is IGF-1 secreted from?
The liver.
Which two hormones inhibit growth hormone secretion?
- Somatostatin from the hypothalamus. - IGF-1 from the peripheral tissue.
Do small adenomas cause headaches in acromegaly patients?
Yes
What percentage of patients with acromegaly have hypertension?
20 - 50%
Can extra-pituitary GH over secretion occur?
Yes, but it is rare.
Pancreatic and bronchial carcinoid tumors can secrete GHRH. True or false?
True, but very rare. This can cause pituitary over-secretion of GH and acromegaly.
Name genetic syndromes in which we can see acromegaly.
McCune-Albright Carney complex MEN-1 syndrome
What conditions can cause a false positive result in oral glucose tolerance test for acromegaly?
- Diabetes - Chronic hepatitis - Renal failure - Anorexia
Should TRH or GHRH stimulation tests be used to test for pituitary hypofunction?
No - because the yield discordant results.
There is a higher prevalence of vertebral fractures in acromegaly. True or false?
True.
Is bone mineral density significantly decreased in acromegaly?
No.
What are the target hormone levels in the treatment of acromegaly?
Growth hormone level of less than 1 mcg/L and IGF-1 level in the normal range.
What is the most common cause of death in acromegaly patients?
Cardiovascular disease.
By roughly how much is life expectancy decreased in acromegaly patients?
On average they live 10 years less than other people.
Should you continue to treat women with acromegaly medically if they become pregnant?
No. Because of lack of available safety information.
How are somatostatin analogs usually given?
As monthly depot injections.
How effective are somatostatin analogs when treating acromegaly?
They achieve adequate IGF-1 suppression in about 50% of cases.
What size does the tumor have to be to have a greater chance of surgical success in acromegaly?
Less than 2 cm
What is the initial dose of Lanreotide for acromegaly? How is it titrated?
60 mg deep SC injection qMonth. Dose titrated every 2 - 3 months until IGF-1 levels are normal or a maximal dose of 120 mg qMonth is reached.
Mechanism of action of Pegvisomant.
Blocks GH action in peripheral tissues by antagonising the GH receptor.
What happens to the GH levels when Pegvisomant (Somavert) is used?
GH level increases.
Normalisation of IGF-1 levels occur in what percentage of patients treated with Pegvisoment?
89%
What is the initial dose of Pegvisomant? How is it titrated?
10 mg SC qDay. Dose increased in 5 mg increments at 4 week intervals until plasma IGF-1 is normal or a maximal dose of 30 mg is reached.
What percentage of patients on Pegvisomant have elevated liver enzymes and how often should these be followed?
25% Should be followed every 6 months.
What percentage of acromegaly patients achieve biochemical control when treated with cabergoline as monotherapy?
Less than 10%
Should radiation therapy be used as first line in the treatment of acromegaly?
No
What is use of gamma-knife in acromegaly limited by?
- Tumor size - Proximity to optic nerve
How long does it take to see full response to radiotherapy (fractionated) in acromegaly?
Up to 15 years.
When is transsphenoidal surgery appropriate in acromegaly?
- Intrasellar microadenomas - Non-invasive macroadenomas - Tumor causing compressive symptoms
What are the surgical cure/control rates for macroadenomas causing acromegaly?
Approximately 50%
What are the surgical cure/control rates for microadenomas causing acromegaly?
90%
What percentage of acromegaly patients have obstructive sleep apnea?
25 - 60%
Do patients with acromegaly have a higher rate of cancer?
Unclear. However, rate of death is higher in acromegaly patients who have colon cancer, so baseline colonoscopy recommended.
How long after surgery for acromegaly should the IGF-1 and GH levels be checked?
3 month
What levels of hormones 3 months post-op define control in acromegaly?
IGF-1 level in normal range or random GH level < 1 mcg/L. An OGTT can be used to assess outcome as well: nadir used is < 0.4 mcg/L
When should an MRI brain be done after surgery for acromegaly?
3 - 4 months.
When should a repeat MRI be done after starting medical therapy for acromegaly?
3 - 6 months
How often should an MRI be followed in patients with acromegaly who have been controlled with surgery?
Every 2 - 3 years
How often should an MRI be followed in patients who are not adequately controlled with surgery?
Yearly
How often should MRIs be done on patients with acromegaly on growth hormone receptor antagonist therapy?
6 months after initiation of therapy and then yearly because of the potential risk of tumor enlargement.
How is polyuria defined?
24-hour urine output > 30 to 50 ml/kg in adults and > 100 ml/kg.
What is dipsogenic diabetes insipidus?
Caused by excessive and inappropriate fluid intake due to a defect in thirst mechanism.
What is the estimated prevalence of central diabetes insipidus?
1 in every 25,000
Overall incidence of transient diabetes insipidus after transsphenoidal surgery of the pituitary.
18.3% - 31%
Overall incidence of permanent diabetes insipidus after transsphenoidal surgery of the pituitary.
0.5 - 2%
What percentage of postoperative DI patients need treatment with DDAVP at least once during the course of their management?
67.5 - 80%
How soon after neurosurgery does diabetes insipidus develop?
1 - 6 days
What percentage increase in basal osmolality is required to induce thirst?
1 - 2%
Patients with DI often crave cold liquids. True or false?
True
What is the urine specific gravity usually in DI?
< 1.001 to 1.010
Fully concentrated urine in the setting of hypernatremia rules out DI. True or false?
True
What is the most likely diagnosis in the case of hyponatremia with polyuria?
Primary polydipsia.
What two electrolyte abnormalities can cause partial nephrogenic DI?
Chronic hypokalemia Chronic hypercalcemia
When do you do a water deprivation test?
Primary polydipsia, central and nephrogenic DI.
Should you do a water deprivation test in the setting of hypertonic hypernatremia?
No. It is unnecessary (because the patient clearly does not have primary polydipsia) and may even be dangerous.
What kind of labs would make you want to do a water deprivation test?
Hypotonic polyuria with normal serum sodium/osmolality.
Which common things should be discontinued before doing a water deprivation tear?
- Caffeine - Alcohol - Tobacco - Drugs affecting ADH
Which parameters/labs are followed hourly to do a water deprivation test?
Body weight Plasma osmolality Serum sodium Urine osmolality Urine volume
When is the water deprivation test stopped?
Body weight decreases by 5% Sodium > 145 mEq/L and osmolality > 295 mOsm/kg Stable urine osmolality i.e. variation of < 5% over 3 hours.
If the urine osmolality remains less than the plasma osmolality in the water deprivation test then this means…
The patient has complete DI with either absent or ineffective ADH.
If the urine osmolality is greater than the plasma osmolality in a water deprivation test, but the urine remains submaximally concentrated then this means…
The patient has either partial DI or primary polydipsia. In primary polydipsia the patient will not get hypernatremic as the water deprivation test proceeds.
How do you differentiate central and nephrogenic DI with a water deprivation test?
At the end of the test DDAVP 0.03 mcg/kg is given SC and urine osmolality is measured at 30, 60 and 120 minutes. If the urine osmolality increases by more than 50% compared to value achieved during dehydration then central DI diagnosis is established.
Mechanism by which kidney is unable to fully concentrate urine in cases of chronic polydipsia.
Polyuria can lead to ‘washout’ of medullary interstitium, with loss of transtubular osmolar gradient required to maintain maximum urinary concentrating ability of the kidneys.
Which other test can be used if the water deprivation test is inconclusive or cannot be performed?
Hypertonic saline test
What are the contraindications for the hypertonic saline test?
Patients at risk for complications of volume over-load e.g. Congestive heart failure.
How is a hypertonic saline test done to distinguish between primary polydipsia, central and nephrogenic DI?
Hypertonic saline (3%) is infused at 0.05 - 0.1 ml/kg/min for 1 - 2 hours, and plasma osmolality and sodium are measured every 30 minutes. ADH is measured once sodium > 145 mEq/L and osmolality > 295 mOsm/kg. Normograms have been established to distinguish between primary polydipsia, partial central DI and partial nephrogenic DI.
How rapidly should hypernatremia be corrected in diabetes insipidus if it developed rapidly over a period of hours?
Decrease sodium at 1 mEq/L/hr
How fast should you correct hypernatremia in diabetes insipidus if it developed slowly - over days?
Decrease sodium at 0.5 mEq/L/hour, up to a maximum of 8 - 10 mEq/L/day, using smallest amount of fluid possible to avoid cerebral edema.
What is the usual dose of intravenous or subcutaneous DDAVP?
1 - 2 mcg once or twice daily
What is the usual dose of intranasal DDAVP?
1 - 4 sprays/day in 1 - 3 divided doses/day. 1 spray = 10 mcg
What is the onset of action of oral DDAVP?
30 - 60 minutes.
What is the onset of action of parenteral DDAVP?
Rapid - instant.
What is the onset of action of intranasal DDAVP?
Rapid - instant
What is the usual dose of oral DDAVP?
0.1 - 0.4 mg one to four times a day with a maximum dose of 1.2 mg/day
Why is oral DDAVP not used as commonly?
Variable gut absorption Reduced bioavailability
How is the dose of DDAVP converted from intranasal to parenteral preparation?
By reducing the dose by a factor of ten.
How is the dose of intranasal DDAVP converted to oral DDAVP?
The dose has to be titrated again due to variable bioavailability.
Bedtime dosing of DDAVP helps some patients reduce disabling nocturia. True or false?
True.
What instructions are given to a patient with diabetes insipidus and intact thirst mechanism?
Drink only when thirsty (to avoid water intoxication and hyponatremia when on DDAVP).
What is an appropriate response to DDAVP?
Urine output of < 300 ml/hour
How are adipsic patients with diabetes insipidus managed?
Fixed dose of DDAVP and adequate hydration. Instructed to adjust fluid intake based on indirect water balance indicators like weight and serum sodium when feasible.
Management of nephrogenic diabetes insipidus?
- Correct associated electrolyte disturbances. - Discontinuation of offending drugs. - Low sodium diet - Thiazide diuretic (stimulates proximal tubular sodium and water reabsorption) - Amiloride (enhances effect of thiazide diuretic; can be used in lithium induced DI because it blocks sodium channels through which lithium enters and interferes with tubular response to ADH.) - NSAIDS - adjunct to treatment (decrease GFR and synthesis of prostaglandins that normally antagonize the action of ADH.
Can DDAVP be effective in patients with partial nephrogenic DI?
Yes
How long does transient diabetes insipidus after pituitary surgery last?
1 - 7 days
What is the rare triphasic pattern of DI following transsphenoidal surgery?
Early DI, followed by normal urine output or SIADH (24 hours to days) due to release of stored hormone, followed by permanent DI (once hormone stores are depleted).
What lab values make you think of SIADH?
Hyponatremia/decreased serum osmolality with inappropriately elevated urine osmolality.
Bromocriptine can cause SIADH. True or false?
True
DDAVP can cause SIADH. True or false?
True
Thymoma can cause DDAVP. True or false?
True
What is an abnormal water load test?
Inability to excrete 80% of a water load (20 ml/kg of water ingested in 10 - 20 minutes) after 4 hours and/or failure to dilute urinary osmolality to < 100 mOsm/kg. Test should be done when serum sodium > 125 mEq/L.
How does hypothyroidism cause hyponatremia?
Proposed mechanisms: - Dysregulation of ADH release or clearance or both. - Effects on vascular tone, cardiac output, and renal blood flow.
How does adrenal insufficiency cause hyponatremia?
Loss of negative feedback (by glucocorticoids) on ADH (ACTH secretagogue).
What happens if you correct hyponatremia too aggressively?
Central pontine myelinolysis
How fast should hyponatremia be corrected where the acuity or chronicity of the hyponatremia is not known?
1 - 2 mEq/L/hour for the first 3 - 4 hours and 0.5 mEq/L/hour after that for a maximum correction of 10 mEq/L per 24 hours.
What is the typical dose of demeclocycline for SIADH?
300 - 600 mg BID
What is the major side effect of demeclocycline?
Nephrotoxicity
What is the onset of action of intravenous conivaptan?
1 - 2 hours.
Vasopressin receptors agonists increase thirst. True or false?
True
Is peri orbital edema present in hyper- or hypothyroidism?
Hypothyroidism
What does dopamine do to TSH?
Suppresses it.
What happens to TSH levels in the first trimester of pregnancy?
They decrease.
What is the most reliable laboratory measurement of thyroid status?
Plasma free T4 by equilibrium dialysis.
Which is the major circulating thyroid hormone?
T4
When should T3 be measured?
In patients with suspected hyperthyroidism with suppressed TSH but normal free T4. Clinical hyperthyroidism with elevation of T3 alone is called T3 toxicosis.
Which cells is thyroglobulin synthesized by?
Thyroid follicular cells.
Which thyroid diseases are plasma thyroglobulins elevated in?
All of them.
What is thyroglobulin used for?
Monitoring patients with papillary or follicular thyroid carcinoma after total thyroidectomy.
Why is an assay for antithyroglobulin antibodies done in conjunction with the thyroglobulin assay?
Because the presence of thyroglobulin antibodies renders the thyroglobulin assay useless.
Why would you measure TSI (thyroid-stimulating immunoglobulins) in a pregnant patient with a history of Grave’s disease?
TSI can cross the placenta and cause neonatal hyperthyroidism. Measuring TSI in the third trimester has some value in predicting this rare complication.
What is the tumor marker for medullary carcinoma of the thyroid?
Plasma calcitonin
What is the definition of radioactive iodine uptake?
Percentage of small oral dose of iodine-131 retained by the thyroid after 24 hours.
What is the normal range of RAIU for dietary iodine intake in the United States?
10 - 30%
What can suppress radioactive iodine uptake temporarily?
Large doses of exogenous iodine in the form of x-ray contrast media or iodine-containing drugs.
When do you do a radioisotope thyroid scan?
When there is a single palpable thyroid nodule in a hyperthyroid patient.
What is the prevalence of incidental thyroid nodules?
20 - 60% of the population
Does ultrasound have any role in evaluation of diffuse goiters, hypo- or hyperthyroidism?
No
What is the method of choice for evaluating thyroid malignancy?
Fine-needle aspiration cytology
What is the most common complication of FNAC?
Transient painful swelling of nodule due to bleeding inside it.
What is low T3 syndrome?
T3 is decreased in non-thyroidal illness; whereas TSH and free T4 remain normal. Occurs in trauma, surgery and starvation etc, and is because of decreased conversion of T4 to T3. Thyroid hormone replacement is not beneficial.
What is low T4 syndrome?
Plasma total T4 falls in severe illness due to decreased TBGs, although free T4 measured by equilibrium dialysis usually remains normal. Free T4 may be low when measured with conventional immunoassays. This is basically euthyroid sick syndrome so the TSH levels initial decrease and then rise again; sometimes to levels higher than normal.
What do androgens do to TBG?
Decrease TBG
What effect do high doses of furosemide and salicylates have on TBG?
Inhibit T4 binding to TBG
What does heparin and low molecular weight heparin do to T4 and TBG?
Displaces T4 from TBG in vitro.
What effect does the placenta have on thyroid function?
The placenta contains high levels of type 3 deiodinase which inactivates T4, and limits T4 transfer from mother to fetus.
What happens to the levothyroxine dose requirements of hypothyroid women who become pregnant?
Dose needs to be increased to maintain euthyroidism.
What happens to urinary iodine excretion in pregnancy?
It increases. Placing fetus at risk of cretinism in areas of iodine deficiency.
What thyroid disease can occur in the months following delivery?
Transient hyperthyroidism from painless thyroiditis (post-partum thyroiditis).
What is the most common cause of euthyroid diffuse goiter in the US?
Hashimoto’s thyroiditis
What kind of goiter does iodine deficiency cause?
Diffuse euthyroid goiter. Can also cause euthyroid multinodular goiter
Is there any evidence that routine thyroid US improves clinical outcomes in patients with multinodular?
No. Not recommended.
What percentage of women have single palpable thyroid nodules?
5%
What percentage of men have single palpable thyroid nodules?
1%
Nearly all palpable single thyroid nodules should be evaluated with FNAC. True or false?
True.
When should plasma calcitonin be measured in case of a single palpable thyroid nodule?
If there is a family history of medullary thyroid carcinoma, MEN 2A or 2B.
What percentage of thyroid nodules with atypical cytology are malignant?
5 - 15%
What are the next steps in evaluation of a single thyroid nodule with an FNAC result showing atypical cytology?
Repeat biopsy. If it is not conclusive then a lobectomy; if carcinoma confirmed then a completion thyroidectomy.
What percentage of thyroid nodules with cytology result ‘follicular neoplasm’ are malignant?
15 - 30%.
How are patients with ‘follicular neoplasm’ on FNAC treated?
Lobectomy, followed by completion thyroidectomy if carcinoma is confirmed.
What is the most common type of thyroid cancer?
Papillary carcinoma of the thyroid.
Where does papillary thyroid carcinoma metastasize to first?
Cervical lymph nodes.
Which thyroid carcinoma is rare and rapidly progressive with a poor prognosis?
Anaplastic thyroid carcinoma
What percentage of thyroid carcinomas are papillary?
80%
What percentage of thyroid carcinomas are follicular?
15%
What percentage of thyroid carcinomas are medullary?
5%
What percentage of thyroid carcinomas are Anaplastic?
Very rare.
What percentage of thyroid carcinomas are thyroid lymphomas?
Very rare.
Which gene usually has mutations in patients with medullary carcinoma of the thyroid?
Mutations of different regions of the RET proto-oncogene.
What is the initial treatment of papillary and follicular carcinoma?
Total thyroidectomy.
How high does the TSH have to be before thyroid remnant ablation can be performed?
TSH > 30 microUnits/ml
How long does levothyroxine therapy typically need to be withheld for before TSH is above 30 and thyroid remnant ablation can be done for thyroid cancer?
2 weeks
What is the dose of radioactive iodine typically given for thyroid remnant ablation?
30 - 100 mCi of RAI
What is the next step after giving RAI for thyroid remnant ablation for thyroid cancer?
Whole body radioactive iodine scan.
What is the TSH goal in patients with risk factors for recurrence of thyroid cancer or with known metastatic disease?
About 0.1 microUnit/mL
What is the TSH goal for low-risk thyroid cancer patients?
0.1 - 0.5 microUnits/mL
How often are whole body iodine scans done and when are they discontinued?
Every 6 - 12 months. It can be discontinued after two consecutive negative scans.
What is the next step if RAI uptake by functioning thyroid tissue is detected on a whole body iodine scan?
Treat with radioactive iodine ablation (usually 100 - 200 mCi).
What are the factors that increase risk of recurrence or mortality in papillary thyroid cancer?
Tumor diameter > 2 cm Invasion through the thyroid capsule Cervical lymph node metastases Distant metastases Age > 45 years
How long do you need to monitor someone with papillary thyroid cancer?
Lifelong.
What percentage of patients with papillary thyroid cancer die of the disease?
5%
What is the primary treatment of medullary carcinoma?
Total thyroidectomy.
Is radioactive iodine therapy useful in medullary carcinoma?
No
Below what size do thyroid nodules not need an FNAC?
Less than 1 cm.
Can radioactive iodine therapy be given in pregnancy?
No. It is contra-indicated.
How effective is radioactive iodine-131 in permanently controlling hyperthyroidism?
Controls in about 90% of the patients.
What dose of RAI are Grave’s disease patients treated with?
8 - 10 mCi
How soon after discontinuing thionamides does hyperthyroidism recur?
Within 6 months of discontinuing therapy.
How often does hyperthyroidism recur or persist after subtotal thyroidectomy?
3 - 7%
What percentage if patients get hypothyroidism after subtotal thyroidectomy?
30 - 50%
What percentage of patients get hypoparathyroidism after subtotal thyroidectomy?
3%
What affect does subclinical hyperthyroidism have on the elderly and those with heart disease?
Increases the risk of atrial fibrillation in the elderly and those with heart disease.
What affect does subclinical hyperthyroidism on postmenopausal women?
Pre-disposes to osteoporosis
Can a male have children while on testosterone?
No. Because it suppresses the body’s natural testosterone.
What is the most reliable laboratory measurement of thyroid status?
Plasma free T4 by equilibrium dialysis.
What does heparin treatment do to free T4 levels?
Elevates them.
Which is the major circulating thyroid hormone?
T4
When should T3 be measured?
In patients with suspected hyperthyroidism with suppressed TSH but normal free T4. Clinical hyperthyroidism with elevation of T3 alone is called T3 toxicosis.
Which cells is thyroglobulin synthesized by?
Thyroid follicular cells.
Which thyroid diseases are plasma thyroglobulins elevated in?
All of them.
What is thyroglobulin used for?
Monitoring patients with papillary or follicular thyroid carcinoma after total thyroidectomy.
Why is an assay for antithyroglobulin antibodies done in conjunction with the thyroglobulin assay?
Because the presence of thyroglobulin antibodies renders the thyroglobulin assay useless.
Why would you measure TSI (thyroid-stimulating immunoglobulins) in a pregnant patient with a history of Grave’s disease?
TSI can cross the placenta and cause neonatal hyperthyroidism. Measuring TSI in the third trimester has some value in predicting this rare complication.
What is the tumor marker for medullary carcinoma of the thyroid?
Plasma calcitonin
What is the definition of radioactive iodine uptake?
Percentage of small oral dose of iodine-131 retained by the thyroid after 24 hours.
What is the normal range of RAIU for dietary iodine intake in the United States?
10 - 30%
What can suppress radioactive iodine uptake temporarily?
Large doses of exogenous iodine in the form of x-ray contrast media or iodine-containing drugs.
When do you do a radioisotope thyroid scan?
When there is a single palpable thyroid nodule in a hyperthyroid patient.
What is the prevalence of incidental thyroid nodules?
20 - 60% of the population
Does ultrasound have any role in evaluation of diffuse goiters, hypo- or hyperthyroidism?
No
What is the method of choice for evaluating thyroid malignancy?
Fine-needle aspiration cytology
What is the most common complication of FNAC?
Transient painful swelling of nodule due to bleeding inside it.
What is low T3 syndrome?
T3 is decreased in non-thyroidal illness; whereas TSH and free T4 remain normal. Occurs in trauma, surgery and starvation etc, and is because of decreased conversion of T4 to T3. Thyroid hormone replacement is not beneficial.
What is low T4 syndrome?
Plasma total T4 falls in severe illness due to decreased TBGs, although free T4 measured by equilibrium dialysis usually remains normal. Free T4 may be low when measured with conventional immunoassays. This is basically euthyroid sick syndrome so the TSH levels initial decrease and then rise again; sometimes to levels higher than normal.
What do androgens do to TBG?
Decrease TBG
What effect do high doses of furosemide and salicylates have on TBG?
Inhibit T4 binding to TBG
What does heparin and low molecular weight heparin do to T4 and TBG?
Displaces T4 from TBG in vitro.
What effect does the placenta have on thyroid function?
The placenta contains high levels of type 3 deiodinase which inactivates T4, and limits T4 transfer from mother to fetus.
What happens to the levothyroxine dose requirements of hypothyroid women who become pregnant?
Dose needs to be increased to maintain euthyroidism.
What happens to urinary iodine excretion in pregnancy?
It increases. Placing fetus at risk of cretinism in areas of iodine deficiency.
What thyroid disease can occur in the months following delivery?
Transient hyperthyroidism from painless thyroiditis (post-partum thyroiditis).
What is the most common cause of euthyroid diffuse goiter in the US?
Hashimoto’s thyroiditis
What kind of goiter does iodine deficiency cause?
Diffuse euthyroid goiter. Can also cause euthyroid multinodular goiter
Is there any evidence that routine thyroid US improves clinical outcomes in patients with multinodular?
No. Not recommended.
What percentage of women have single palpable thyroid nodules?
5%
What percentage of men have single palpable thyroid nodules?
1%
Nearly all palpable single thyroid nodules should be evaluated with FNAC. True or false?
True.
When should plasma calcitonin be measured in case of a single palpable thyroid nodule?
If there is a family history of medullary thyroid carcinoma, MEN 2A or 2B.
What percentage of thyroid nodules with atypical cytology are malignant?
5 - 15%
What are the next steps in evaluation of a single thyroid nodule with an FNAC result showing atypical cytology?
Repeat biopsy. If it is not conclusive then a lobectomy; if carcinoma confirmed then a completion thyroidectomy.
What percentage of thyroid nodules with cytology result ‘follicular neoplasm’ are malignant?
15 - 30%.
How are patients with ‘follicular neoplasm’ on FNAC treated?
Lobectomy, followed by completion thyroidectomy if carcinoma is confirmed.
What is the most common type of thyroid cancer?
Papillary carcinoma of the thyroid.
Where does papillary thyroid carcinoma metastasize to first?
Cervical lymph nodes.
Where does a follicular carcinoma typically metastasize to?
Lung and bone.
Which thyroid carcinoma is rare and rapidly progressive with a poor prognosis?
Anaplastic thyroid carcinoma
What percentage of thyroid carcinomas are papillary?
80%
What percentage of thyroid carcinomas are follicular?
15%
What percentage of thyroid carcinomas are medullary?
5%
What percentage of thyroid carcinomas are Anaplastic?
Very rare.
What percentage of thyroid carcinomas are thyroid lymphomas?
Very rare.
Which gene usually has mutations in patients with medullary carcinoma of the thyroid?
Mutations of different regions of the RET proto-oncogene.
What is the initial treatment of papillary and follicular carcinoma?
Total thyroidectomy.
Which patients get radioactive iodine thyroid remnant ablation?
- All patients with follicular carcinoma. - Patients with papillary carcinoma who are at increased risk of tumor recurrence.
How high does the TSH have to be before thyroid remnant ablation can be performed?
TSH > 30 microUnits/ml
How long does levothyroxine therapy typically need to be withheld for before TSH is above 30 and thyroid remnant ablation can be done for thyroid cancer?
2 weeks
What is the dose of radioactive iodine typically given for thyroid remnant ablation?
30 - 100 mCi of RAI
What is the next step after giving RAI for thyroid remnant ablation for thyroid cancer?
Whole body radioactive iodine scan.
What is the TSH goal in patients with risk factors for recurrence of thyroid cancer or with known metastatic disease?
About 0.1 microUnit/mL
What is the TSH goal for low-risk thyroid cancer patients?
0.1 - 0.5 microUnits/mL
How often are whole body iodine scans done and when are they discontinued?
Every 6 - 12 months. It can be discontinued after two consecutive negative scans.
What is the next step if RAI uptake by functioning thyroid tissue is detected on a whole body iodine scan?
Treat with radioactive iodine ablation (usually 100 - 200 mCi).
What are the factors that increase risk of recurrence or mortality in papillary thyroid cancer?
Tumor diameter > 2 cm Invasion through the thyroid capsule Cervical lymph node metastases Distant metastases Age > 45 years
How long do you need to monitor someone with papillary thyroid cancer?
Lifelong.
What percentage of patients with papillary thyroid cancer die of the disease?
5%
What is the primary treatment of medullary carcinoma?
Total thyroidectomy.
Is radioactive iodine therapy useful in medullary carcinoma?
No
Below what size do thyroid nodules not need an FNAC?
Less than 1 cm.
Can radioactive iodine therapy be given in pregnancy?
No. It is contra-indicated.
How effective is radioactive iodine-131 in permanently controlling hyperthyroidism?
Controls in about 90% of the patients.
What dose of RAI are Grave’s disease patients treated with?
8 - 10 mCi
How soon after discontinuing thionamides does hyperthyroidism recur?
Within 6 months of discontinuing therapy.
How often does hyperthyroidism recur or persist after subtotal thyroidectomy?
3 - 7%
What percentage if patients get hypothyroidism after subtotal thyroidectomy?
30 - 50%
What percentage of patients get hypoparathyroidism after subtotal thyroidectomy?
3%
What affect does subclinical hyperthyroidism have on the elderly and those with heart disease?
Increases the risk of atrial fibrillation in the elderly and those with heart disease.
What affect does subclinical hyperthyroidism on postmenopausal women?
Pre-disposes to osteoporosis
Can a male have children while on testosterone?
No. Because it suppresses the body’s natural testosterone.
Does PTU cross the placenta?
Yes
Which anti-thyroid medication can you breast feed on?
Methimazole
Can levothyroxine be taken with calcium or iron supplements?
No
What is the prevalence of adrenal incidentalomas in the general population?
3%
Is a homogeneous adrenal mass < 4 cm with smooth borders and an attenuation value < 10 Houndfield units benign or malignant?
Benign
Is an adrenal lesion > 6 cm, regardless of appearance on CT scan, more likely to be benign or malignant?
Malignant.
What is the treatment of a primary adrenocortical malignancy?
Surgical removal.
If an adrenal nodule turns out to be metastatic cancer or a primary non-adrenal cancer (e.g. lymphoma) then what is the treatment?
Generally no surgical removal is needed but rather treatment of the primary cancer.
The adrenal gland must lose what percentage of function before it poses any risk of adrenal crisis?
70 - 80%
What is the treatment of choice for aldosterone-secreting tumors?
Surgical removal
What is the treatment of choice for primary adrenal hyperplasia?
Medical management.
How often should imaging be done in adrenal incidentalomas during follow-up?
3 - 6 months
How often are adrenal incidentalomas biochemically evaluated?
Every 5 years.
What is the leading cause of primary adrenal insufficiency in the United States?
Autoimmune adrenalitis
Name two medications that increase cortisol metabolism.
Rifampin Phenytoin
Name medications that decrease cortisol secretion by inhibiting cortisol biosynthesis.
Ketoconazole Aminoglutethimide Etomidate Suramin
Is hyperpigmentation caused in primary or secondary adrenal insufficiency and why?
Primary adrenal insufficiency. Increased ACTH secretion stimulates the melanocortin receptor to upregulate melanin synthesis.
What percentage of patients have antibodies in primary adrenal insufficiency?
90%
What antibodies are present in primary adrenal insufficiency?
- Adrenal cortex antibody (ACA) - 21-hydroxylase (CYP21A2) antibody
What is the dose of fludrocortisone for primary adrenal insufficiency?
0.05 to 0.2 mg PO qDay
What parameters is the fludrocortisone dose titrated to in primary adrenal insufficiency?
- Orthostasis - Blood pressure normalization - Normalization of potassium levels - Suppression of plasma renin activity to the middle to upper end of the normal range.
What is the dose of DHEA in primary and secondary adrenal insufficiency?
25 - 50 mg daily
How is congenital adrenal hyperplasia transmitted genetically?
Autosomal recessive genetic disorder.
What are most cases of pseudohermaphroditism due to?
Classic congenital adrenal hyperplasia.
50% cases of ambiguous genitalia are because of congenital adrenal hyperplasia. True or false?
True
What is the main enzyme deficiency in 95% of cases of congenital adrenal hyperplasia?
21-hydroxylase deficiency
What is the second most common enzyme deficiency (5 - 8%) in congenital adrenal hyperplasia?
11-beta-hydroxylase deficiency
What is 11-beta-hydroxylase deficiency characterized by?
Virilization and low-renin hypertension.
What is the incidence of nonclassic congenital adrenal hyperplasia?
0.1 - 0.2%
Which gene is affected in congenital adrenal hyperplasia?
CYP21A2
What are ‘salt wasters’?
No 21-hydroxylase activity - insufficient aldosterone to retain sodium.
What are ‘simple virilizers’?
Low but detectable 21-hydroxylase deficiency - virilized, but do not waste sodium.
What are the common features of nonclassic congenital adrenal hyperplasia?
Hirsutism, oligomenorrhea and acne.
How do males with nonclassical congenital adrenal hyperplasia present?
Small testes to the phallus, oligospermia, infertility, and short stature.
Levels of what are elevated in cases of congenital adrenal hyperplasia?
17-OH progesterone
What level of 17-OH progesterone has been reported to have 100% specificity and 90% sensitivity?
> 400 ng/dL
How do you diagnose congenital adrenal hyperplasia if the value of 17-OH progesterone is between 200 ng/dL and 400 ng/dL?
The gold standard for hormonal diagnosis is the cosyntropin stimulation test. 17-OHP is measured before and 60 minutes after. Patients with nonclassic CAH will usually have 17-OHP > 1000 ng/dL,
Treatment for classic ‘salt-wasting’ CAH.
Glucocorticoid and mineralocorticoid replacement and sodium chloride supplementation.
When do you treat nonclassical 21-hydroxylase deficiency?
If infertility or hyperandrogenism is unacceptable to the patient.
What is the preferred treatment of congenital adrenal hyperplasia in children?
Hydrocortisone 10 - 15 mg/m2/day in two or three divided doses. After completion of linear growth, long acting glucocorticoids are preferred.
What is the most common complication of treatment of CAH?
Decreased height due to either incomplete suppression of hyperandrogenism, or conversely, due to overtreatment-induced hypercortisolism.
What does a normal 17-OHP level represent when monitoring the treatment of CAH?
Overtreatment. 17-OHP is relatively resistant to glucocorticoid suppression.
Treatment goals for 17-OHP and androstenedione levels in CAH.
17-OHP - upper limit of normal or slightly supranormal. Androstenedione - upper one third of normal range.
Can women with CAH get pregnant?
Yes
Do women with non-classical CAH require glucocorticoid therapy during pregnancy?
No
What is the most important thing to distinguish in Conn’s syndrome?
Whether it is unilateral or bilateral disease because that determines therapy.
Which hormone stimulates the release of aldosterone?
Renin
What is ‘aldosterone escape’?
Phenomenon in Conn’s syndrome where increased urinary sodium and decreased urinary potassium mediated by ANP counter-act the effects of excess aldosterone.
What is the most common presentation of primary aldosteronism?
Normokalemic hypertension
Inheritance of familial hyperaldosteronism type 1/glucocorticoid-remediable aldosteronism.
Autosomal dominant
What is familial hyperaldosteronism type 1 associated with?
Bilateral adrenal hyperplasia.
Which hormone drives the production of aldosterone in familial hyper aldosteronism type 1?
ACTH
What happens when you give thiazide diuretics to patients with glucocorticoid-remediable hyper aldosteronism?
The develop marked hypokalemia.
What do complications do patients with glucocorticoid-remediable aldosteronism?
Cerebrovascular complications like ruptured aneurysms.
Familial aldosteronism type 1 is caused by the recombination of which promoter and coding regions of which genes?
Promotor region of 11-beta-hydroxylase (CYP11B1) and coding regions of 18-hydroxylase to make a chemeric gene.
How long should you wait before changing the calcitriol dose?
24 - 48 hours
Nesidioblastosis. What is it?
Beta-cell hypertrophy after gastric bypass surgery.
What’s the first line medical treatment of insulinoma?
Diazoxide
Is familial hyperaldosteronism type 2 ACTH dependent or independent?
ACTH independent
What pattern of inheritance does familial hyperaldosteronism type 2 have?
Autosomal dominant
What does familial hyperaldosteronism type 2 lead to?
Aldosterone producing adenomas Idiopathic hyperaldosteronism
A locus on which chromosome has been implicated in familial hyperaldosteronism type 2?
7p22
In which patients should you consider screening for GRA (glucocorticoid-remediable aldosteronism) via PCR-based genetic testing?
- Onset prior to 20 years of age - Family history of primary aldosteronism - Personal or family history of stroke prior to age 40.
What does the plasma aldosterone concentration have to be to diagnose primary hyperaldosteronism?
PAC > 20 ng/dL
What should the aldosterone renin ratio (ARR) be if you have primary hyperaldosteronism?
ARR > 30 ng/dL per ng/mL/hour
Should you use the aldosterone renin ratio alone instead of in conjunction with plasma aldosterone concentration?
No
What do ACEIs do to PRA?
Increase it
What do ARBs do to PRA?
Increase it
How do you confirm renin-independent hyperaldosteronism?
Nonsuppression of aldosterone during sodium loading.
What effect do diuretics have on aldosterone renin ratio?
Decrease it
What should the potassium be before salt loading to test for primary hyperaldosteronism?
Normal. Replete if needed.
How much sodium should a patient take for oral salt loading test for primary hyperaldosteronism?
6 grams/day for 3 days
What should the 24-hour urine aldosterone be after oral salt loading in a patient with primary hyperaldosteronism?
> 12 to 14 mcg/24h
What does the plasma aldosterone concentration have to be after 4 hours of IV saline to confirm a diagnosis of primary hyperaldosteronism?
PAC > 10 ng/dL
What level of PAC refutes a diagnosis of primary hyperaldosteronism after 4 hours for IV saline?
PAC < 5 ng/dL
What does it mean when PAC is between 5 ng/dL and 10 ng/dL after 4 hours of IV saline for salt loading?
Considered a ‘grey zone’ for diagnosis of primary hyperaldosteronism.
What tests other than salt loading can be used to diagnose primary hyperaldosteronism?
Fludrocortisone suppression test Captopril challenge test
What is the localization procedure of choice for primary hyperaldosteronism?
Adrenal vein sampling (AVS)
How does hypothyroidism cause hyponatremia?
Impaired free water excretion.
What are the target free T4 levels in pregnancy?
High normal: 1.4 - 1.8 ng/dl
How does hypothyroidism cause hyponatremia?
Impaired free water excretion.
What are the target free T4 levels in pregnancy?
High normal: 1.4 - 1.8 ng/dl
When should you use the extended/combination or dual wave bolus feature on the insulin pump?
When the meal is high fat (more than 30% of the calories from fat) and carbohydrates.
Make a suggested percentage setting for the square wave or combination/extended portion of the insulin pump her eating higher carbohydrate foods like pizza or pizza?
70% initially and 30% later.
Suggest the percentages to use with the square wave or combination/extended portion on the insulin pump to use with fatty meals like eggs, sausage, biscuit or fried foods?
60% initially and 40% later
What should the duration of the extended/combination or square portion of the bolus be typically?
1 - 2 hours for most meals.
What range of durations can you select for the extended/combination or square portion of the bolus on the insulin pump?
30 minutes to 6 hours
At what age can PCOS start?
Girls as young as 11.
What is the first-line management of menstrual abnormalities and hirsutism/acne in PCOS?
Hormonal contraceptives.
Should patient with differentiated thyroid cancer get a radiology-performed ultrasound of the thyroid or a clinician-performed one?
Clinician-performed ultrasound of the thyroid. It evaluates the lateral neck for pathologic lymph nodes.
What happens to the hippocampal volume at higher HbA1c levels?
It decreases.
Higher HbA1c levels and glucose levels are related to higher levels of cognitive decline in older people. True or false?
True.
Which two major trials published in NEJM in late 2013 showed the DDP-4 inhibitors did not decrease cardiovascular risk when compared to placebo?
SAVOR TIMI-53 trial (Saxagliptin versus placebo) EXAMINE trial (Alogliptin versus placebo)
What happens to the insulin requirements during puberty?
Increases
What works better in infections: sulfonylureas or DPP-4 inhibitors?
Sulfonylureas
Can hypercalcemia cause diabetes insipidus?
Yes
Can imaging alone localise aldosterone production?
No
What is the concordance between CT and AVS?
Approximately 50%
Do people with glucocorticoid-remediable aldosteronism need to get adrenal vascular sampling?
No. Their disease is usually bilateral.
What lateralisation ratio is indicative of unilateral aldosterone excess in an AVS?
More than 4:1
What does a lateralisation ratio of less than 3:1 during an AVS mean?
The aldosterone source is bilateral.
How much potency does eplerenone have compared to spironolactone?
60% of spironolactone
What percentage of people treated surgically for hyperaldosteronism have persistent hypertension post-operatively?
40 - 70%
Which type of Cushing’s is more common: ACTH dependent or ACTH independent?
ACTH dependent hypercortisolism
What is Cushing’s disease?
ACTH secreting pituitary adenoma
How is Carney’s complex inherited?
Autosomal dominant
How do you differentiate between Cushing’s and pseudo-Cushing’s syndrome?
CRH after dexamethasone test. Depressed patients continue to show suppressed cortisol even after CRH infusion.
How can you tell if a patient has ACTH-independent or ACTH-dependent Cushing’s?
Measure ACTH and basal cortisol.
What is the first line medical treatment for Cushing’s?
Ketoconazole
Which enzymes does ketoconazole inhibit?
- 17 to 20 lyase - 11-beta-hydroxylase - cholesterol side chain cleavage enzyme
Which enzymes does mitotane inhibit?
- Cholesterol side-chain cleavage enzyme. - 11-beta-hydroxylase.
Which medication can cause medical adrenalectomy by causing permanent destruction of adrenocortical cells?
Mitotane
What else do you need to start when initiating mitotane?
Glucocorticoid replacement.
Which enzyme does metyrapone inhibit?
11-beta-hydroxylase
What does Nelson’s syndrome usually cause?
Enlargement of the pituitary. Extreme elevations in ACTH levels. Hyperpigmentation.
Can someone getting an AVS be on hydrochlorothiazide?
No. It lowers potassium.
What are the Hounsfield unit cut-off below which an adrenal tumor is likely benign?
10 HU
What anticonvulsant can be used in conjunction with other medications to treat Cushing’s syndrome?
Aminoglutethimide
How do you treat Cushing’s syndrome/disease in pregnancy?
Bilateral adrenalectomy may be performed. Transsphenoidal surgery for Cushing’s disease. Metyrapone can be used in pregnancy. Aminoglutethimide can be used in pregnancy.
What do patients with untreated Cushing’s syndrome normally die of?
Cardiovascular/thromboembolic complications Bacterial/fungal infections
What should the cortisol level suppress to to rule out Cushing’s syndrome?
Less than 1.8
What are the cure rates for Cushing’s disease after transsphenoidal surgery?
80 - 90%
How long after surgery for Cushing’s should the HPA axis be evaluated to determine potential need for lifetime exogenous steroid replacement?
6 - 12 months.
Where do extraadrenal paragangliomas arise from?
From catecholamine-producing cells in the sympathetic and parasympathetic ganglia.
What is the goal fasting glucose in pregnancy?
60 - 90 mg/dl
What’s the second most common location for tumors secreting growth hormone?
Pancreas
Would it be likely for a patient to have Conn’s syndrome and a pheochromocytoma at the same time?
Extremely unlikely. No reported cases.
If insulin requirements decease during pregnancy in a diabetic in the third trimester, what should you think of?
Placental insufficiency.
If you can’t find a precipitating cause of primary hypogonadism then what should you do?
Get a karyotype to rule out Klinefelter’s syndrome.
Can you put insulin in tube feeds?
No
Can you have Hashimoto’s and Grave’s at the same time?
Yes
What are two tricks for not making blood glucose checks hurt?
- Use hot water - Use side of finger
Does dialysis remove some circulating insulin as well?
Some… Maybe 30% or so, depending on the membrane.
What is the risk of hypothyroidism when you ablate patients with toxic nodules/ toxic multinodular goiter?
8%
If a HIV patient’s have increasing CD4 counts, what can happen to their Grave’s disease?
Can worsen.
What percentage of micro vascular complications is a high HbA1c responsible for? Grand rounds - misinterpretation of study.
11%
What does weight loss do to triiodothyronine levels?
Deceases them
What question can you ask to see if someone is taking their insulin?
How long does a vial of insulin last.
What happens if you give just zinc to someone with mineral deficiencies?
They can develop copper deficiency.
Do you give steroids before or after radioactive iodine treatment in the case of Grave’s ophthalmopathy?
Long steroid taper afterwards starting with prednisone 40 mg qDay.
Can radioactive iodine ablation cause leukopenia?
Transiently.
What medication is Xgeva?
Denosumab.
Can levothyroxine formulations cause a strange odor in the urine?
Yes
What is a radioactive glucose scan used for?
Seeing if there is a concentration of metabolically active cells i.e. early malignancy.
How to make male to female people develop female voice after puberty?
Speech therapy.
What is the inheritance pattern of familial hyperaldosteronism type 2?
Autosomal dominant
Is familial hyperaldosteronism type 2 ACTH dependent or independent?
ACTH independent
A locus on which chromosome has been implicated in familial hyperaldosteronism type 2?
Chromosome 7p22
Can chewing tobacco affect screening for hyperaldosteronism?
Yes. As do other products derived from licorice root.
What should the plasma aldosterone level be higher than in primary hyperaldosteronism?
20 ng/dL
What should the aldosterone renin ratio be higher than in primary hyperaldosteronism?
30
Typically, how big is an adrenocortical carcinoma on CT imaging?
More than 4 cm.
What’s the difference between type 1a and type 1b diabetes mellitus?
Type 1b is anti-body negative type 1 diabetes.
Which pituitary cells are acidophilic?
Somatotrophs Lactotrophs
Which receptor does cabergoline cross react with to cause potential valvular abnormalities?
5-HT 2B (Serotonin receptor)
What should you think of in a patient with diabetes and deafness?
Maternally inherited diabetes and deafness.
How is maternally inherited diabetes and deafness inherited?
Mitochondrial DNA
What is the incidence of maternally inherited diabetes and deafness?
1%
What kind of deafness occurs in maternally inherited diabetes and deafness syndrome?
Sensorineural deafness
Which sulfonylurea and you use in renal failure?
Glipizide
Which pituitary cells are acidophilic?
Somatotrophs Lactotrophs
Which receptor does cabergoline cross react with to cause potential valvular abnormalities?
5-HT 2B (Serotonin receptor)
What should you think of in a patient with diabetes and deafness?
Maternally inherited diabetes and deafness.
How is maternally inherited diabetes and deafness inherited?
Mitochondrial DNA
What is the incidence of maternally inherited diabetes and deafness?
1%
What kind of deafness occurs in maternally inherited diabetes and deafness syndrome?
Sensorineural deafness
What is the ‘Calment Limit’?
122 years Oldest well-documented age achieved by Jeanne Louise Calment, who died in 1997.
What happens to the protective telomere structures that cap the ends of chromosomes as part of the normal ageing process?
Telomere attrition i.e. progressive shortening
What EKG finding is diagnostic of autonomic neuropathy?
Perfectly regular R-R intervals that don’t change with respiration.
What question should you ask a male who you suspect of having autonomic neuropathy?
Whether or not he has erectile dysfunction.
Can opioids inhibit ACTH?
Yes
Which hormones are most commonly affected by opioids: LH and FSH Or ACTH
LH and FSH
What does a clonidine suppression test test for?
Pheochromocytoma
Can cabergoline cause hallucinations?
Yes
Can hypothyroidism cause elevated creatinine?
Yes. Secondary to myopathy.
Can hypothyroidism cause transaminitis?
Yes
Can hypothyroidism cause anemia?
Yes
Can cabergoline treat galactorrhea?
Yes
Which anti-depressant decreases prolactin levels?
Aripipazole (Abilify)
Is cosyntropin given IV or IM?
IV
What do you expect the estradiol level to be if a patient is on oral contraceptives?
Low
Can celiac disease cause hypothyroidism?
Yes
If a child has type 1 diabetes and so does the parent - which parent is more likely to have type 1 diabetes?
The father is 5 x more likely to have type 1 diabetes.
Is hyperglycemia alone enough to develop complications of diabetes?
No. It has to be host factor and hyperglycemia.
Why don’t they like using red bags for peritoneal dialysis?
They have the highest glucose content and cause earlier failure of peritoneal dialysis due to increased angiogenesis.
What is glumetza?
Metformin
How can you establish the correct diagnosis in bilateral adrenal enlargement and primary adrenal insufficiency?
CT-guided percutaneous adrenal biopsy. (Because enlarged adrenal glands or calcifications suggest an infectious, hemorrhagic or metastatic cause.)
How do you screen for kidney disease in a patient with type 1 diabetes for less than 5 years?
Serum creatinine
How do you screen for kidney disease in a patient with type 1 diabetes for 5 years or more?
Urine albumin to creatinine ratio every year. (ADA 2014)
How does fluoride affect trabecular bone?
Increases the bone density.
How does fluoride affect the cortical bone?
The bone density does not change or it deceases slightly.
Roux-en-Y gastric bypass surgery has a greater likelihood of achieving diabetes remission than with adjustable gastric banding. True or false?
True
Which diabetic complication are Hispanic type 2 diabetes patients more likely to develop?
Retinopathy
What should you check first in a pre-menopausal woman with irregular bleeding?
Beta hCG (Pregnancy test)
Acute and transient hypophosphatemia can result from prolonged hyperventilation. True or false?
True
Is radioactive iodine ablation recommended after surgery in stage 1 papillary thyroid cancer?
No. It may not decrease risk of recurrence or death.
Is diazoxide contra-indicated in heart failure?
Yes. Also can cause heart failure.
What creatinine level is alpha-glucosidase inhibitor contra-indicated at?
2
How do you monitor for pancreatic rejection in a combined kidney pancreas transplant?
When the creatinine goes up (surrogate marker) then you would check amylase.
Familial lipodystrophy cause loss of fat on which part of the body?
Legs
Which part of the body loses fat in acquired lipodystrophy?
Upper extremities
What testosterone formulation is hard to get the correct dosage on?
Testosterone pellets
Do you have to over-lap insulin infusion when you are transitioning to pump?
No
What average blood glucose level does a HbA1c of 7% correlate to?
154 mg/dl
What average blood glucose level does a HbA1c of 8% correlate to?
183 mg/dl
What average blood glucose level does a HbA1c of 9% correlate to?
212 mg/dl
What average blood glucose level does a HbA1c level of 10% correlate to?
240 mg/dl
What average blood glucose level does a HbA1c of 11% correlate to?
269 mg/dl
What average blood glucose level does a HbA1c of 12% correlate to?
298 mg/dl
What average blood glucose level does a HbA1c of 5% correlate to?
97 mg/dl
Can you do a cosyntropin stimulation test when a patient is on dexamethasone?
Not unless he only received 1 or 2 doses.
What would you recommend for someone with osteopenia/osteoporosis and calcium oxalate kidney stones?
2 servings of dairy.
How long after being transplanted does a parathyroid gland start working?
A few months afterwards. If the parathyroid hormone levels are still low after a year or so then it probably work pick up.
Are steroids picked up in cortisol assays?
Only hydrocortisone. (Dexamethasone, methyl-prednisone, prednisone etc are not picked up).
When is baseline serum cortisol helpful?
When it is very low (less than 5 microgram/dL) or clearly elevated.
Can you have adrenal insufficiency with a normal DHEA-S?
No - usually this rules out adrenal insufficiency. Adrenal insufficiency patients have low DHEA-S, but it can be low in patients who do not have adrenal insufficiency as well.
What other hormones should you check for besides baseline cortisol, ACTH and DHEA-S when primary adrenal insufficiency is suspected?
Aldosterone level and renin activity.
At and above what cortisol level in the ambulatory setting is the diagnosis of adrenal insufficiency extremely unlikely?
12 microgram/dL
What is the dominant regulatory mechanism for aldosterone?
Renin-angiotensin system
What happens to the plasma volume because of loss of mineralocorticoid secretion in primary adrenal insufficiency?
Decrease in plasma volume.
What is the half life of DHEA-S?
10 - 12 hours
Where is DHEA and DHEA-S secreted from?
Zona fasciculata
Does DHEA-S have a circadian rhythm?
No.
What is the dosage of metyrapone?
30 mg/kg with maximal dose of 3000 mg.
What should the cortisol level be after metyrapone test?
Less than 5 microgram/dL
What should the 11-deoxycortisol level be after the metyrapone test?
More than 7 microgram/dL
Metyrapone test can rule out adrenal insufficiency if the sum of cortisol and 11-deoxycortisol is greater than…
16.5 microgram/dL
What is the normal cosyntropin-stimulated serum free cortisol concentration in critically ill patients?
3.1 microgram/dL or more.
What does luteinizing hormone do in males?
Stimulates testosterone production
What does FSH do in males?
Stimulates sperm production.
What is the normal ratio of T4 to T3 in humans?
14:1
What is the ratio of T4 to T3 in Armour thyroid?
5:1
When was insulin discovered?
1922
How much does the pituitary gland weigh?
Half a gram
What do you do if you have Aspart and the tube feeds got stopped?
Start dextrose 10% at the same rate as the tube feeds.
When should you consider secondary causes of osteoporosis?
When the Z-score is less than - 2
What is the other name for endocrine disorder ‘Gordon Syndrome’?
Pseudohypoaldosteronism type 2
If the HbA1c is more than 8% is the problem with the fasting blood glucose or the post-prandial?
Fasting
If the HbA1c is 7.5% or less is the problem with the fasting blood glucose or post-prandial?
Post-prandial.
What is evolocumab?
PCSK9 inhibitor
What role does physical activity play in heart disease in women?
Physical inactivity is a top factor for heart disease in women.
What is indapamide?
Thiazide diuretic
Which SSRI is good for hot flashes?
Venlafaxin
Does calcium gluconate cause tissue necrosis if extravasated?
Yes. But less than calcium chloride.
What kind of bed does a patient with hypocalcemia need to have while in the hospital?
Telemetry bed
If someone is on a calcium gluconate drip and the calcium is not going up what should you consider?
Make sure the pharmacy mixed it to 1 mg/kg
In what syndrome do you have primary hyperparathyroidism associated with pituitary and adrenal tumors?
MEN 4
Which inhaled insulin recently got FDA approved?
Insulin Afrezza
Which syndrome is characterized by the following: - hypercortisolism from hyperplastic adrenal macronodules - cafe-au-lait spots - polyostotic fibrous dysplasia
McCune-Albright syndrome
What are the main effects of IGF-1?
(Hint: 3 effects)
- Growth of bone and cartilage.
- Impaired glucose tolerance.
- Changes in protein and fat metabolism.
What condition is characterized by the following: - micronodular adrenal hyperplasia - pituitary adenomas - testicular tumors - thyroid tumors - cardiac atrial myxomas - pigmented lentigines - blue nevi - Schwannomas
Carney’s complex
What’s the difference between type 1a and type 1b diabetes mellitus?
Type 1b is anti-body negative type 1 diabetes.
When does Nelson’s syndrome usually occur?
Cushing’s disease (pituitary adenoma) with refractory disease treated with bilateral adrenalectomy.
What common echocardiographic findings are seen in acromegaly?
(Hint: 2 points)
- Intraventricular septum thickening and left posterior wall hypertrophy, with diastolic dysfunction.
- Systolic dysfunction occurs less often.
When is medical treatment of acromegaly done?
(Hint: 4 points)
- Tumors with low probability of surgical cure.
- Temporizing measure before surgery to improve comorbidities.
- Control symptoms before radiation therapy achieves full effects.
- After surgery if full biochemical control is not achieved.
Where do pheochromocytomas arise from?
Catecholamine-producing chromaffin cells in the adrenal medulla.
What average blood glucose is a HbA1c of 6% equal to?
126 mg/dL
Where are extraadrenal pheochromocytomas most commonly located?
(Hint: 5 points).
- Carotid body of the head and neck
- Mediastinum
- Close to IVC and abdominal aorta alongside sympathetic ganglia
- Organ of Zuckerkandl
- Near urinary bladder
If a patient has polyuria in the setting of Uosm > 300 mOsm/kg what is it due to?
Solute diuresis most commonly from diuretics or hyperglycemia.
If someone has been on high dose steroids every few days for a number of years - how would you taper their steroids if they still need them?
Check their adrenal axis - if normal then can just stop steroids and follow-up.
If cannot check adrenal axis because of recent use then put on physiologic dose of steroids and test when convenient.
Do diabetes have an increased incidence of pancreatitis?
Yes
What does having celiac disease do to hip fracture risk?
Increases it.
What is the initial dose of octeotride LAR in acromegaly?
10 mg IM qMonth.
Can increased calcium intake during lactation prevent bone loss?
Not completely.
Which sulfonylurea and you use in renal failure?
Glipizide
What are the three main side effects of Somatostatin analogs?
- Abdominal bloating and cramping - usually improves over the first few months of treatment.
- Gallstones - usually do not cause acute cholecystitis.
- Pancreatitis - rare.
Do SSRIs have increased risk of osteoporosis?
No
How is octeotride LAR titrated in acromegaly?
The dose is increased every 2 - 3 months until IGF-1 levels are normal or maximum dose of 40 mg IM qMonth is reached.
