Endocrine Flashcards
Subclinical hypothyroidism (TSH >10 µU/mL) associations
TSH is either below or above the normal range, free T3 or T4 levels are normal, and the patient has no symptoms of thyroid disease
increased LDL cholesterol.
Subclinical hyperthyroidism (TSH <0.1 µU/mL) is associated with
the development of atrial fibrillation,
decreased bone density,
cardiac dysfunction
S/E drugs hypothyroidism
Lithium
Amiodarone
S/E lithium
Hypothyroidism
Hyperparathyroidism –> elevated Ca –> tx: stop Lithium for 3 mo
S/E delayed gastric emptying/gastroparesis
amylin analogues (e.g., pramlintide) glucagon-like peptide 1 (e.g., exenatide)
Diabetic drug not ok for:
- avoiding wt loss (eg for elderly)
- renal failure
- lactic acidosis
- heart failure
- hypoglycemia
- avoiding wt loss = Exenatide
- renal failure = Metformin
- lactic acidosis = Metformin
- heart failure = pioglitazone
- hypoglycemia = glipizide
1st line for diabetes
Metformin
Does not cause wt gain
criteria for diagnosing diabetes mellitus
symptoms of diabetes (polyuria, polydipsia, weight loss) + a casual glucose level ≥200 mg/dL;
a fasting plasma glucose level ≥126 mg/dL on 2 occasions;
or a 2-hour postprandial glucose level ≥200 mg/dL after a 75 gram glucose load.
hemoglobin A1c level ≥6.5%
The criteria for impaired glucose homeostasis
fasting glucose level of 100-125 mg/dL (impaired fasting glucose)
or a 2-hour glucose level of 140-199 mg/dL on an oral glucose tolerance test.
Normal values glucose
<140 mg/dL for the 2-hour glucose level on an oral glucose tolerance test.
When evaluating a patient with a solitary thyroid nodule, red flags indicating possible thyroid cancer include
male gender;
age 65 years;
rapid growth of the nodule;
symptoms of local invasion such as dysphagia, neck pain, and hoarseness;
a history of head or neck radiation; a family history of thyroid cancer;
a hard, fixed nodule >4 cm;
cervical lymphadenopathy
S/E hypothyroidism in children
markedly delayed bone age relative to height age and chronologic age
What is diagnostic of iron deficiency anemia
Low serum ferritin
Dx at any stage!
Indications for parathyroid surgery include
kidney stones,
age less than 50,
a serum calcium level greater than 1 mg/dL above the upper limit of normal,
reduced bone density
Primary HYPOthyroidism
ON levothyroxine
TSH is below nl
NO sx of hypo or hyper thyroidism
What do you do for her?
Decrease dose of levothyroxine
In a patient receiving levothyroxine, a low TSH level usually indicates overreplacement. If this occurs, the dosage should be reduced slightly and the TSH level repeated in 2–3 months’ time.
Med tx for hyperthyroidism
Side effect?
PTU
Methimazole
Agranulocytosis is feared
Best to use these drugs for adolescents who can go into remission after a few months
Test for secondary hypothyroidism
TRH stimulation test
See if increases TSH
Levothyroxine is….
T4
Hypercalcemia S/E
Stones
- renal calculi
Bones
- bone pain
Psychic groans
- poor concentration
- weakness
- fatigue
- stupor
- coma
Abdominal moans
- ab pain
- constipation
- N/V
- pancreatitis
- anorexia
REMEMBER YOU CAN LOSE WEIGHT FROM HYPERCALCEMIA AND NOT HAVE IT BE A MALIGNANCY RELATED HYPERCALCEMIA!!!! Do work up with PTH and then urinary Ca first before jumping to malignancy
What meds should you start with in new diabetics?
Insulin sensitizers
Metformin
Glitizones
Metformin
- MoA
- S/E
- decreases hepatic gluconeogeneiss, increased insulin sensitivity
S/E:
- rare lactic acidosis
- big GI side effects
- NOT OK for renal or liver failure
Diabetes drugs that cause wt loss
Metformin
Exenatide
Diabetes drugs that cause weight gain
Glitazones
PIoglitazone, rosiglitazone
- MoA
- S/E
- increase insulin sensitivity in adipose and muscle
- dec hepatic gluconeogenesis
S/E: wt gain hepatotoxicity fluid retention - NOT OK IN LIVER DZ AND CHF
Sulfonylureas (Glyburide, glimepriride, glipizide)
- MoA
- S/E
- increase insulin secretion by pancreas
S/E:
- disulfiram like effects in 1st gen
- hypoglycemia
- NOT ok for DKA
- possible increased CV mortality w/ 1st and 2nd gen
Diabetes drugs causing hypoglycemia
Sulfonylureas
Pramlintide
Repaglinide
Nateglinide
Gliptins if combo w/ sulfonylureas
Acarbose, miglitol
- MoA
- S/E
a-glucosidase inhibitors
- inhibit at brush border
- dec postprandial glucose levels
S/E:
GI (flatus, diarrhea)
- NOT OK FOR CIRRHOSIS AND GI DZ
Pramlintide
- MoA
- S/E
decreases glucagon
S/E:
- hypoglycemia
- nausea
- diarrhea
Repaglinide, nateglinide
- MoA
- S/E
- stimulates insulin release in presence of glucose
- need to take with meal to work
S/E:
hypoglycemia
acute hepatotoxicity (repaglinide)
- NOT OK with metabolic acidosis
Exenatide, liraglutide
- MoA
- S/E
GLP-1 analog
- stimulates insulin release (incretin mimetic)
- slows gastric emptying
S/E:
- caution with renal failure
- acute pancreatitis
- wt loss
LInagliptin, saxagliptin, sitagliptin
- MoA
- S/E
- increase incretin levels DPP-IV inhibitor, and this class of drugs inhibits the enzyme responsible for the breakdown of the incretins GLP-1 and GIP
S/E:
- hypoglycemia when combo w/ sulfonylurea
- possible increased risk of acute pancreatitis
Hypothyroidism sx
Symptoms often include fatigue, bradycardia, dry skin, brittle hair, and a prolonged relaxation phase of the deep tendon reflexes
Careful considerations when giving levothyroxine
Rapid replacement of thyroid hormone can increase the metabolic rate, and therefore myocardial oxygen demand, too quickly. This can precipitate complications of coronary artery disease such as atrial fibrillation, angina, and myocardial infarction.
Best tx for diabetes with renal failure
Glipizide
not renally excreted
the goal for patients with type 2 diabetes mellitus is to achieve a hemoglobin A1c of
<7.0%
You have been asked to see a 75-year-old female who has just had hip surgery to correct a fractured femoral neck. She has a 2-year history of diabetes mellitus treated with pioglitazone (Actos), 30 mg daily, and metformin (Glucophage), 1000 mg twice daily. She is now fully alert and has been able to eat her evening meal. A physical examination is normal except for her being mildly overweight and having a bandage on her left hip. A CBC and chemistry profile done earlier today were normal except for a serum glucose level of 200 mg/dL. Her hemoglobin A1c at an office visit 2 weeks ago was 6.8%.
Which one of the following would be the best management of this patient’s diabetes at this time? (check one)
A. Stop her usual medications and begin a sliding-scale insulin regimen
B. Stop the metformin only
C. Initiate an insulin drip to maintain glucose levels of 80–120 mg/dL
D. Decrease the dosage of pioglitazone
E. Continue with her usual medication regimen
E
Current evidence indicates that traditional sliding-scale insulin as the only means of controlling glucose in hospitalized patients is inadequate. For patients in a surgical intensive-care unit, using an insulin drip to maintain tight glucose control decreases the risk of sepsis but has no mortality benefit. Metformin should be stopped if the serum creatinine level is ≥1.5 mg/dL in men or ≥1.4 mg/dL in women, or if an imaging procedure requiring contrast is needed. In patients who have not had their hemoglobin A 1c measured in the past 30 days, this could be done to provide a better indication of glucose control. If adequate control has been demonstrated and no contraindications are noted, the patient’s usual medication regimen should be continued
Comprehensive foot exam for diabetes should include
Testing for loss of protective sensation
pinprick sensation
ankle reflexes
Assessment of pedal pulses
Skin changes such as hair loss and temperature changes
Breaks, ulcers in skin
bony abnormalities
The patient’s footwear should also be inspected for abnormal patterns of wear and appropriate sizing.
Cortisol levels can be assessed with
a single serum reading,
or by the change in the cortisol level after stimulation with cosyntropin
What is target glucose level in critically ill pts?
recommend insulin infusion with a target glucose level of 140–180 mg/dL
Initial test for adrenal insufficiency
single morning serum cortisol level >13µg/dL reliably excludes adrenal insufficiency.
If the morning cortisol level is lower than this, further evaluation with a 1µg ACTH stimulation test is necessary,
What is the only hypoglycemic agent shown to reduce mortality rates in patients with type 2 diabetes mellitus
Metformin
How to screen for primary hyperadosteronism?
ratio of morning plasma aldosterone to plasma renin.
A ratio >20:1 with an aldosterone level >15 ng/dL suggests the diagnosis.
Renal contraindications for diabetes meds
Metformin NOT OK in females w/ creatinine level ≥1.4 mg/dL and in males with a creatinine level ≥1.5 mg/dL
Acarbose should be avoided in patients with cirrhosis or a creatinine level >2.0 mg/dL.
Exenatide is not recommended in patients with a creatinine clearance <30 mL/min
Adrenal mass discovered…what happens next?
Once an adrenal mass is identified, adrenal function must be assessed with an overnight dexamethasone suppression test.
- A morning cortisol level >5 μg/dL after a 1-mg dose indicates adrenal hyperfunction.
Additional testing should include 24-hour fractionated metanephrines and catecholamines to rule out pheochromocytoma.
If the patient has hypertension, morning plasma aldosterone activity and plasma renin activity should be assessed to rule out a primary aldosterone-secreting adenoma.
Nonfunctioning masses require assessment with CT attenuation, chemical shift MRI, and/or scintigraphy to distinguish malignant masses.
Thyroid nodule found…next step?
TSH level
Suppressed TSH –> radionuclide thyroid scan
- if hot nodule, usually not malignant and bx not needed
All other TSH –> FNA
What levels do you get for hypothyroidism?
TSH
T4
Women older than 65 years of age who have low serum TSH levels, indicating physiologic hyperthyroidism, are at increased risk for
new hip and vertebral fractures.
Use of thyroid hormone itself does not increase the risk of fracture if TSH levels are normal.
Diabetes drug not causing hypoglycemia
Metformin
What are the only agents approved for treatment of type 2 diabetes mellitus in children.
Metformin
insulin
Hyperthyroid and preggers
PTU preferred over methimazole only in 1st trimester
Second and third trimester prefer methimazole
The most common cause of hypoglycemia in a previously stable, well-controlled diabetic patient who has not changed his or her diet or insulin dosage is
diabetic renal disease
Which comes first usually: retinopathy or nephraopathy?
retinopathy
