Endocrine Flashcards
Causes of panhypopituitarism
Anything that damages the brain
- Tumor
- Infection
- Trauma
- Stroke
In what order are hormones lost in the pituitary
GH, and LH, FSH first
ACTH last
Results of LH, FSH deficiencies
W - Amenorrhea
M - No testosterone or sperm, ED, decreased muscle
Both have decreased libido, body hair
Kallman syndrome points
Decreased GnRH causing decreased LH, FSH
Anosmia
Renal agenesis (50%)
Presentation of GH deficiency
Children - Short stature
Adults - Central obesity, Increased LDL, chol, Reduced lean muscle
Features of pituitary apoplexy
Prior adenoma
HA
Changing MS
Send to ICU for hormone replacement
What is Sheehan
Postpartum pituitary necrosis
Can’t lactate
Confirmatory test for low TSH and thyroxine
Decreased TSH response to TRH
Confirmatory test for decreased ACTH and cortisol
Normal response to cosyntropin stimulation
No response w/ CRH
Elevated cortisol excludes pituitary problem
Confirmatory test for Low GH
No response to arginine
No response to GHRH
Confirmatory test for low prolactin
No response to TRH
Failure of GH to rise in response to insulin
Pituitary insufficiency
What does metyrapone do
ACTH levels rise
Hormonal problems in empty sella
NONE
What is diabetes insipidus
Decrease in ADH amount or function on kidneys
Causes of central DI
Any destruction
- Stroke
- Trauma
- Hypoxia
- Infiltration
Causes of nephrogenic DI
Chronic pyelo
Amyloidosis
Myeloma
Sickle cell
Drugs inducing NDI
Li
Demeclocycline
Colchicine
Metabolic changes inducing NDI
Hypercalcemia
Hypokalemia
Presentation of DI
High volume urine
Excessive thirst
Volume depletion
Hypernatremia
What causes neuro sx in SI
Hypernatremia
What does water deprivation test show in DI
Urine osmolality doesn’t increase
Vasopressin effect in CDI
Decrease urine volume
Increase urine osmolality
Vasopressin effect in NDI
Nothing
Obscure manifestation of NDI
Loss of access to water
- NPO before surgery
Rx CDI
Long term desmopressin
Rx NDI
Treat underlying cause
HCTZ, amiloride, NSAIDs
What is acromegaly
Overproduction of GH
MCC acromegaly
Pituitary adenoma
Can be part of MEN
2 Conditions causing B/L carpal tunnel syndrome
Acromegaly
Hypothyroidism
Features of Acromegaly
B/L carpal tunnel Increasing hat/shoe/ring size Coarse facial features Macroglossia Colon polyps HTN Cardiomegaly/CHF Bitemporal hemianopsia ED
Best initial test for acromegaly
IGF-1
Most accurate test for acromegaly
Glucose suppression test
NL - glucose suppresses GH
What additional tests must be done for acromegaly
Prolactin (cosecreted)
MRI (after labs)
Rx acromegaly
Surgery - transphenoidal resection Meds - Octreotide (rx of choice) - Cabergoline (inhibit GH) - Pegvisomant (GHr antagonist) Radiotherapy - Non-responsive to meds/surg
MCC of hyperprolactinemia
Functional adenoma (prolactinoma)
What must always be r/o as cause of hyperprolactinemia
Hypothyroidism
- High TRH leads to prolactin secretion
ONLY CCB to raise prolactin
Verapamil
Physiological causes of hyperprolactinemia
Pregnancy, nursing
Intense exercise, stress
Renal insufficiency
Drugs raising prolactin levels
Antipsychotics Methyldopa Metoclopromide Opioids TCAs
Presentation of hyperprolactinemia
W - Amenorrhea, galactorrhea, infertility
M - ED, decreased libido, visual disturbances
First Dx test in hyperprolactinemia
Check prolactin levels
Other tests in hyperprolactinemia
Exclude pregnancy BUN/Cr LFTs Exclude thyroid and drugs MRI
Rx hyperprolactinemia
DA agaonists - Cabergoline
Transphenoid surgery - No med response
Radiation - Last resort
Who to aggressively rx for hyperprolactinemia
Pts of childbearing age to prevent infertility
Men
Complication of transphenoidal resection for hyperprolactinemia
30% get panhypopituitarism
Cause of hypothyroidism
Failure of gland from burnt out Hashimoto’s thyroiditis
Rare- Dietary def iodine, Amiodarone, Li
When to immediately treat hypothyroidism
TSH 2x NL AND NL T4
TSH
AKA Antithyroid peroxidase
Antithyroglobulin
Features of hypothyroidism
Brady Constipation Wt gain Fatigue, lethargy, coma ↓ DTRs Cold intolerance Hypothermia Pseudodementia
Features of hyperthyroidism
Tachy, palpitations, arrhythmia Diarrhea Wt loss Anxiety, restlessness ↑ DTRs Heat intolerance Fever
Best initial test for thyroid disorders
TSH
What to do when TSH is suppressed
Measure T4
What is seen in exogenous T4 ingestion
Decreased TBG
Rx hypothyroidism
Lifelong thyroxine
Secondary hypothyroid - Add hydrocortisone
Diagnosis hyperthyroidism w/ proptosis and skin findings
Graves
Diagnosis hyperthyroidism w/ tender thyroid
Subacute
Diagnosis hyperthyroidism w/ nontender, normal exam
Painless thyroiditis
Diagnosis hyperthyroidism w/ Involuted gland (not palpable)
Exogenous thyroid use
Diagnosis hyperthyroidism w/ high TSH
Pituitary adenoma
TSH receptor Abs are in
Graves
Features of Graves
Women, 40s Exopthalmos (can get worse w/ rx) High output cardiac failure Pretibial myxedema RAIU - diffuse uptake
Features of subacute thyroiditis
Elevated ESR
May spontaneously resolve
Rx w/ ASA, steroids
Rx graves
Radioactive iodine ablation
Rx painless thyroiditis
None
Rx pituitary adenoma
Surgery
Rx Thyroid storm
Propranolol Methimazole > PTU Iodinated contrast - block peripheral conversion Steroids Radioactive iodine
Thyroid storm in pregnancy
Surgery > RAI ablation
Features of thyroid storm
Fever > 104
CNS sx
Cardiac sx
Rx graves opthalmopathy
Steroids
Radiation if nonresponsive
Surgical decompression
First step in hyperfunctioning thyroid nodule
TSH, T4 levels
U/S to evaluate size
Dx tests in euthyroid thyroid nodule
Bx if >1cm w/ fine needle aspiration
No need to U/S or RAIU
Non-functioning nodule w/ Hx head/neck radiation
CA until proven otherwise
MC CA thyroid
Papillary
Rx total thyroidectomy
FNA shows follicular cells
Remove whole nodule
Can’t differentiate between adenoma and carcinoma
Features of anaplastic thyroid CA
Older pts
Worst prognosis
Rare
Thyroid CA w/ FHx
Medullary
MCC hypercalcemia
Primary hyperparathyroidism
2nd MCC hypercalcemia
Malignancy (PTHrP)
Other causes of hypercalcemia
Vit D tox Sarcoid HCTZ Hyperthyroidism Mets, MM Prolongued immobilization
Acute Sx in hypercalcemia
Confusion
Stupor
Lethargy
Constipation
Cardio manifestation of hypercalcemia
Short QT
Bone manifestation of hypercalcemia
Osteoporosis
Renal manifestation of hypercalcemia
Stones
NDI
Renal insufficiency
Rx hypercalcemia
Saline hydration at high volume
Long term bisphosponates
Short term calcitonin
Prednisone - sarcoid, granulomatous
Drug inhibits PTH release
Cincalcet
Causes of primary parathyroidism
Solitary adenoma MCC
4-gland hyperplasia
Parathyroid malignancy
Sx hyperparathyroidism
Osteoporosis
Nephtolithiasis and renal insufficiency
Muscle weakness, anorexia, N/V, abd pain
PUD
Dx tests in hyperparathyroidism
High Ca, PTH, Cl, BUN/Cr, ALP
Low PO4
Short QT
Rx hyperparathyroidism
Surgical removal
Cincalcet if surgery not an option
What to watch for post op in hyperparathyroidism
Hypocalcemia
MCC hypocalcemia
Complication of prior neck surgery
Other causes of hypocalcemia
Hypomagnesemia Renal failure VIt D deficiency Genetic disorders Fat malabsorption Low albumin
Signs of hypocalcemia
Chovstek Spasm Perioral numbness Mental irritability Seizures Tetany
Dx tests for hypocalcemia
Prolongued QT on EKG
Slit lamp exam shows cataracts
Rx hypocalcemia
Replace Ca and Vit D
What is Cushing syndrome
Hypercortisolism
Overproduction of ACTH
MCC hypercortisolism
Iatrogenic
Other causes of cushing syndrome
Pituitary overproduction (Cushing disease)
Adrenal overproduction
Unknown source
Ectopic
Features of Cushing
Fat redistribution - moon face, buffalo hump Skin - striae, easy bruising Osteoporosis HTN Menstrual disorders, ED Cognitive disturbance Polyuria
Best initial test for presence of hypercortisolism
24hr urine cortisol
Secondary test for presence of hypercortisolism
1mg overnight dexamethasone suppression test
Most specific test for presence of hypercortisolism
24hr urine cortisol
Best initial test for the cause of hypercortisolism
ACTH levels
Cushing w/ elevated ACTH
Pituitary or Ectopic
Cushing w/ decreased ACTH
Adrenal source
Cushing w/ elevated ACTH suppressed by dexamethasone
Pituitary source
Cushing w/ elevated ACTH not suppressed by dexamethasone…what now?
Ectopic or CA
- MRI brain
- Petrosal sinus sample
- Chest scan
Rx hypercortisolism
Surgically remove source
Workup of incidentaloma
Metanepherines
Renin, aldosterone
Dexamethasone suppression test
What is Addison’s disease
Chronic hypoaldosteronism
MCC addison’s
Autoimmune
Less common causes of Addison’s
Infection (TB)
Adrenoleukodystrophy
Mets
Causes of acute adrenal crisis
Hemorrhage Surgery Hypotension Trauma Sudden removal of steroids
Presentation of Addison’s
Fever Altered MS N/V Anorexia Hypotension Hyponatremia Hyperkalemia Hyperpigmentation
Specific finding in Addison’s
Eosinophilia
Most specific test for adrenal function
Cosyntropin
No change in Addison’s
Rx Addison’s
Replace steroids
Fludrocortisone
Mineralocorticoids
First thing to do in acute adrenal crisis
Give Steroids
What is primary hyperaldosteronism
Autonomous overproduction of aldosterone despite high BP and low renin
What causes secondary hyperaldosteronism
Decreased intravascular volume
- Dehydration
- Edema → Increased renin
- Hypotension
Who gets secondary hyperaldosteronism
Under 30, over 60
Not controlled w/ 2 HTN meds
Characteristic findings or labs
Important findings in primary hyperaldosteronism
High BP
Low K
High aldosterone
Low renin
Best initial test for primary hyperaldosteronism
Ratio of plasma aldosterone to renin
Most accurate test for primary hyperaldosteronism
High aldosterone from venous blood from adrenal showing unilateral adenoma
Rx primary hyperaldosteronism
Unilateral adenoma - resect
Bilateral hyperplasia - spironolactone/eplerenone
Spironolactone AE
Gynecomastia
Decreased libido
Pheochromocytoma rule of 10s
10%
- Children
- B/L
- Malignant
- Recur
Features of pheochromocytoma
Episodic HTN
HA
Sweating
Palpitations and tremor
Best initial test pheochromocytoma
Plasma metanephrines
Alternate tests for pheochromocytoma
24hr urine metanephrines
VMA
When is MIBG scanning used
Locates pheochromocytoma outside of adrenal
Rx Pheochromocytoma
BIT - Phenoxybenzamine/phentolamine esp pre-op
BBs, CCBs, IVF
Surgical removal
What is DM
Fasting glc >125 on 2 occasions
Features of DM I
Childhood onset
IDDM
Insulin deficiency
Features of DM II
Adult onset
NIDDM - resistance
Obesity
DM presentation
Polyuria, Polydipsia
Decreased wound healing
Dx test for DM
Fasting glc >125 on 2 occasions separated by 1-2wks
Glc > 200 w/ sx
Increased glc on glc tolerance testing
HbA1c >6.5
Best initial drug therapy for DM
Metformin
Goal of oral hypoglycemics
HbA1c
Mechanism of metformin
Block gluconeogenesis
Contraindication to glitazones
CHF
Contraindication metformin
Renal dysfunction
Can cause metabolic acidosis
Mechanism of nateglinide/repaglinide
Stimulate insulin release
Mechanism of alpha glucosidase inhibitors
Block glc absorption in the bowel
Mechanism of pramlintide
Decrease gastric emptying, glucagon, appetite
Glc in HHNS
1000s
Glc in DKA
400s-500s
Presentation of DKA
Hyperventilation Altered MS Metab acid Hyperkalemia Increased anion gap Ketones
Who gets DKA
I > II
Precipitated by infection, MI, stress
Rx DKA
High volume saline
Insulin
K when serum K NL
Most accurate measure of severity of DKA
Low serum bicarb
All DM pts should receive
Pneumococcal vaccine Yearly eye exam Statins - LDL >100 ACEi/ARB - BP > 130/80 Aspirin - age >30 Foot exam
CV complications in DM
MI
Stroke
CHF
Renal complications in DM
Microalbuminuria
Levels of albumin have elevated to 30-300 per 24hrs
Screening for microalbuminuria in DM
Yearly
Rx microalbuminuria in DM
ACE/ARB
Rx DM gastroparesis
Metoclopromide
Erythromycin
Retinopathy in DM
Proliferative retinopathy
Screening of DM retinopathy
I - 5yrs after dx, then yearly
II - yearly
Mechanism of neuropathy in DM
Damage to the vasonervosum
Rx DM neuropathy
Pregabalin
Gabapentin
TCAs