Endocrinology Flashcards
4 ways to diagnose diabetes?
- Two fasting glucose >126
- One random glucose >200 with symptoms
- 2 hour 75g gtt > 140
- HgbA1c > 6.4
Metformin mechanism of action?
Bigaunide. Inhibits hepatic gluconeogenesis, decreases intestinal glucose absorption, increases insulin sensitivity
2nd line agent for DM2 and what is their mechanism of action?
Sulfonylureas (glipizide, glimepiride, glyburide). Act by stimulating pancreatic islet beta-cell insulin release
Adverse side effects of sulfonylureas?
Hypoglycemia, SIADH
Dipeptidyl peptidas IV inhibitors. examples and MOA?
Sitagliptan and Saxagliptan. Blocks metabolism of incretis (such as glucagon like peptide)
Thiazolidinediones. Examples and MOA?
Rosiglitazone, Pioglitazone. Act by increasing peripheral insulin sensitivity
Which diabetes medication should be avoided in chf and why?
Thiazolidinediones. Because they can precipitate or worsen CHF.
Alpha-glucosidase inhibitors. Examples and MOA?
Acarbose and Miglitol. Block absorption of glucose at intestinal lining.
Side-effects of alpha-glucosidase inhibitors (acarbose)?
Since they inhibit glucose uptake at GI lining, will see bloating, distension, flatulance, diarrhea, abdominal pain.
Insulin secretagogues. Examples and MOA?
Nateglinide and Repaglinide. act similar to sulfonylureas, stimulate insulin release. Risk of hypoglycemia
Glucagon like peptides. Examples and MOA?
Exenatide. Increase insulin and decrease glucagon. They slow gastric emptying and promoted weight loss.
Best initial test when suspecting DKA?
Serum bicarbonate
Medical therapy for diabetic retinopathy refractory to laser photocoagulation?
VEGF innhibitors: Ranibizumab or Bevacizumab
Treatment for diabetic gastroparesis?
Metoclopramide or erythromycin (erythromycin increases the release of “motilin” a promotility GI hormone
Graves disease, radioactive iodine uptake increased or decreased? Treatment?
Increased
- Propylthiouracil (PTU) or methimazole acutely
- Then radioactive iodine to ablate the gland
- Propranolol for hyperthyroid symptoms (tremors, palpitations, etc)
Silent thyroiditis clinical and lab/imaging findings?
non tender thyroid gland, no other physical exam findings. Normal radioactive iodine uptake, increased T3/T4 with low TSH. Thyroid peroxidase or antithyroglobulin antibodies may be present
Subacute thyroiditis clinical and lab/imaging findings? Treatment?
Tender gland. radioactive iodine uptake low. T3/T4 high with low TSH. Can give aspirin for pain.
Hyperthyroidism with elevated TSH. Diagnosis, management and treatment?
Pituitary adenoma. Next step get MRI of brain and remove adenoma.
Management of thyroid storm?
Iodine - blocks uptake of iodine into thyroid gland
PTU or methimazole - blocks production of thyroxine
Dexamethasone - Blocks peripheral conversio of T3 to T4
Propranolol
Most common cause of hypercalcemia?
Primary hyperparathyroidism
Symptoms of hypercalcemia?
Kidney stones, osteopenia, ab pain/constipation, confusion
stones, bones, groans, psychiatric overtones
Severe hypercalcemia EKG findings?
Short QT syndrome
Treatment of acute severe hypercalcemia?
Fluids mainstay. Add furosemide to help with calcium excretion. Can add bisphosphonates or calcitonin
Chvostek’s or Trousseau’s sign indicate?
Hypocalcemia
3 sources of hypercortisolism causing cushings?
Pituitary tumor, Ectopic ACTH production, adrenal adenoma
Cushings syndrome and positive dexamethasone suppression test. Diagnosis?
Pituitary tumor
Workup for cushings syndrome?
ACTH level, dexamethasone suppression test and 24 hour urinary cortisol level
Diagnostic test to evaluate for adrenal insufficiency (Addison’s Disease)?
Cosyntropin (synthetic ACTH) stimulation test
CT of adrenals
Example of a glucocorticoid and a mineralocorticoid?
Hydrocortisone - Glucorticoid
Fludrocortisone - Mineralocorticoid
Difficult to control BP along with headache, palpitations, tremors, flushing. Suspicious for? What test to evaluate?
Pheochromocytoma
Order urinary catecholamines, plasma-free metanephrine and VMA levels
Get CT or MRI of adrenals
Concern for metastatic pheochromocytoma, what test?
MIGB scan
Treatment for pheochromocytoma?
- Phenoxybenzamine (alpha blocker for BP)
- Propranolol
- Surgery
Drugs that can cause elevated prolactin levels?
Metoclopramide, phenothiazines, TCAs.
Also always evaluate TSH. hypothyroidism can cause elevated prolactin as well
Next diagnostic step after prolactin level found elevated?
MRI of brain
Treatment of prolactinoma?
Dopamine agonists (Bromocriptine, cabergoline) Surgery if that doesn't work
Best initial test to confirm diagnosis of acromegaly?
Insulinlike Growth Factor (IGF)
Most accurate test for acromegaly?
Glucose induced GH suppression test
Treatment for acromegaly?
- Transpheonidal surgical resection cures 70%
- Octreotide (somatostatin) can prevent GH release
- Dopamine agonists (Cabergoline, Bromocriptine)
Girl presents with primary amenorrhea. Breasts present, but no cervix, tubes, or ovaries. Missing top third of vagina. Diagnosis?
Testicular Feminization a.k.a. Androgen insensitivity syndrome
Tall man with XXY karyotype, sterile and elevated FSH and LH levels. Diagnosis?
Klinefelter’s syndrome
55 y/o with recently diagnosed diabetes and ring-shaped red area that blisters, erodes and crusts over, eventually starts clearing from center. Name of rash and underlying diagnosis?
Necrolytic migratory erythema. Evaluate for underlying glucagonoma.
Asymptomatic adrenal mass noted incidentally on CT scanning. Labs to evaluate?
Dexamethasone suppression, ACTH, 24 hour urine cortisol, serum electrolytes, vanillylmandelic acid, plasma metanephrines, 17-ketosteroid
Criteria for surgical excision of adrenal mass?
- Functional tumors
- Malignant appearing on imaging
- Size greater than 4 cm
