Endocrine Flashcards
MC thyroid cancer (70-75%)
Papillary Carcinoma
2nd MC thyroid cancer (10%)
Follicular Carcinoma
Activation of receptor tyrosine kinases
Papillary and Medullary carcinoma
Hashimoto thyroiditis is a risk factor
B-cell lymphoma
Cancer arising from Parafollicular C cells
Medullary Carcinoma
Commonly associated with RAS mutation or PAX8-PPAR gamma 1 rearragement
Follicular carcinoma
Commonly associated with rearrangements in RET oncogene or NTRK1
Papillary carcinoma
MC mutation in the BRAF gene (serine/threonine kinase)
Papillary carcinoma
What should you measure in a thyroidectomy patient with post-op perioral tingling?
Calcium level. If parathyroids are removed during thyroidectomy then the pt will be hypocalcemic
How is Hb glycosylated in diabetes (HbA1c)?
Non-Enzymatic glycosylation
What cells have GLUT-2 receptor?
Beta cells of the pancreas (important bc glut2 receptors allow beta cells to monitor glucose levels)
Small intestine
Liver
Kidney
Which tissues require insulin for glucose uptake?
Skeletal muscle, Adipose tissue (GLUT-4)
What enzyme converts glucose to sorbitol?
Aldose reductase
Which tissues lack sorbitol DH, the enzyme that converts sorbitol to fructose?
Schwann cells, Retina and lens, Kidney
Lactic acidosis is a rare, but worrisome AE
Metformin
MC AE is hypoglycemia
Sulfonylureas:
- Glyburide
- Glimepiride
- Glipizide
Recommended first-line tx for most pts
Metformin
Not safe in settings of hepatic dysfunction or CHF
TZDs
- Pioglitazone
- Rosiglitazone
Should not be used in pts with elevated serum creatinine
Metformin
Shouldn’t be used in pts with cirrhosis or IBD
Alpha-glucosidase inhibitors
- Miglitol
- Acarbose
Not associated with weight gain
Metformin, DPP-4 inhibitors, GLP-1 analogs
Metabolized by liver, excellent choice in pts with renal dz
TZDs
MOA: Closes K channel on beta cells, leading to depolarization=>Calcium influx=>insulin release
Sulfonylureas
- Glyburide
- Glimepiride
- Glipizide
MOA: inhibits alpha-glucosidase at intestinal brush border
Alpha-glucosidase inhibitors
- Acarbose
- Miglitol
MOA: agonist at PPAR-gamma receptors=> improved target cell response to insulin
TZD:
Pioglitazone
Risoglitazone
MOA: decreases hepatic gluconeogenesis
Metformin
Good for weight loss
GLP-1 Agonist
Avoid in hypoglycemia
Sulfonylureas
Best treatment for anyone with organ failures (renal, liver, heart)
Insulin
What are the five categories for the diagnosis of metabolic syndrome
Abdominal obesity Elevated triglycerides Low HDL Elevated BP Elevated glucose
At what BMI is a pt considered obese?
> 30
What are the three functions of vitamin D?
Calcium absorption from gut
Phosphate absorption from gut
Bone resorption of Ca and PO4
How does PTH increase Ca levels
Increasing bone resorption
Increasing renal reabsorption in the DCT
Where does PTH “trash” phosphate?
PCT
What cells make PTH?
Chief cells of the parathyroid
What cells make Calcitonin?
Parafollicular C cells of the thyroid
what are the two signs of hypocalcemia
Chvostek’s sign
-tap the cheek=>facial muscle contraction
Trousseau’s sign
-Tighten a BP cuff on the arm=>Carpopedal spasm
What are the two MCC of primary hyperparathyroidism?
Solitary parathyroid adenoma
Parathyroid hyperplasia
