Diseases of the Endocrine System

Question 1

Thyroid nodules in euthyroid patients

Answer 1

Could be cancer but incidence is low
FNA dx of choice
If benign, follow but don't intervene
If malignant, thyroid lobectomy
Total thyroidectomy if follicular cancer found

Question 2

Thyroid nodules in hyperthyroid patients

Answer 2

Almost never cancer, but may be hyperfunction
Signs of hyperthyroid: wt loss even though eating lots, palpitation, heat intolerance, moist skin, fidget, hyperactive, tachycardia, A fib
TSH low, T4 high
Most tx w/ radioactive iodine; hot adenoma can have surgical excision

Question 3

Hyperparathyroidism

Answer 3

Usually incidental lab finding of high calcium
Rarely stones, bones, and groans
Look for low phos to r/o cancer w/ bone mets
Find PTH levels
Asymptomatic become symptomatic 20% per year
90% have single adenoma
Removal is curative
Sestamibi scan may help locate culprit

Question 4

Cushings

Answer 4

Round ruddy, hairy face, buffalo hump, supraclavicular fat pads, abdominal striae, fat trunk w/ skinny arms
Osteoporosis, diabetes, HTN, and mental instability also present
Workup w/ low dose dexamethasone suppression test- suppression at low dose=rules out
24h urine free cortisol- if elevated go to high dose suppression test
Suppression at high dose- pituitary microadenoma
No supression at either dose- adrenal adenoma
MRI for pituitary; CT for adrenal
Remove that shit

Question 5

Zollinger-Ellison (Gastrinoma)

Answer 5

Virulent peptic ulcer disease resistant to all therapy
More extensive- many ulcers beyond 1st portion of duodenum
Some patients also have watery diarrhea
Measure gastrin and secretin levels; if equivocal- get CT w/ contrast of pancreas
Remove it; omeprazole if mets

Question 6

Insulinoma

Answer 6

Produce CNS symptoms b/c low sugar; always when patient is fasting
Ddx; reactive hypoglycemia or self admin insulin
If self induced, no c-peptide; but insulinoma has high c-peptide
CT of pancreas to locate and then remove it

Question 7

Glucagonaoma

Answer 7

Severe migratory necrolytic dermatitis resistent to all therapy
Mild diabetes
Anemia glossitis, and stomatits
Glucagon assay is diagnositc & CT locates
Resection is curative
Somatastin & streptozocin help w/ metastatic and inoperable disease