Endocrinology Flashcards
A 43yo obese man present for a health maintenance visit. On physical exam, it is noted that his waist circumference is 106cm and bp is 148/92. Which of the following fasting lab levels would suggest a dx of metabolic syndrome (syndrome X) in this pt?
a) HDL of 45 mg/dL
b) LDL of 180 mg/dL
c) Triglyceride of 190 mg/dL
d) glucose of 100 mg/dL
c: Metabolic syndrome is found in approx. 25% of Americans. It is defined as 3 or more of the following: waist circumference greater than 102cm in men or greater than 88 in women; serum triglyceride level of at least 150 mg/dL, HDL level of less than 40mg/dL in men or less than 50 mg/L in women; blood pressure of at least 130/85; and serum glucose level of at least 110 mg/dL
A 36yo woman presents to the office complaining of weight loss and a feeling of “nervousness.” She also complains of losing hair during the last several weeks. Exam reveals a diffusely enlarged, firm, non-tender thyroid gland with an audible bruit. Her eyes have marked proptosis and lid retraction. Her TSH is very low; her free and total thyroid hormone levels are elevated. What is the most likely dx?
a) subacute thyroiditis
b) Hashimoto thyroiditis
c) Graves disease
d) mulinodular goiter
e) Cushing Disease
c: This pt is suffering from Graves disease. Her symptoms are consistent with a hyperthyroid state. Based upon her physical exam, Graves disease is the most likely diagnosis due to the specific associated eye findings of thyroid-associated ophthalmopathy. The lab findings of low TSH and elevated FT4 are also consistent with the dx.
A 23yo woman present with joint pain, anorexia, amenorrhea, and fatigue. On further questioning, she says that she has been craving salty foods and gets dizzy easily when she stands. Upon physical exam, she is found to have darkened skin over her palms and extensor surfaces and postural hypotension. An 8am plasma cortisol level is low. What test is the gold standard to dx her condition?
b: Adrenal crisis may present with a history of fatigue, anorexia, weight loss, oligomenorrhea or amenorrhea, joint or back pain, and darkening of the skin. Pts may have postural dizziness, food cravings, hyponatremia, hypoglycemia, hyperkalemia, and pre renal azotemia. The 8am plasma cortisol levels may serve as a screening tool for adrenal insufficiency. The gold standard test to dx this is an ACTH stimulation test. This test will also differentiate between primary and secondary adrenal insufficiency.
A 44yo man has been drinking large quantities of water, up to 12L/day, for the last week. In addition, he has been passing large quantities of urine. Upon physical exam, there are no remarkable findings except for increased capillary refill time and tacky mucous membranes. Lab results show sodium 166, potassium 4.2, chloride 123, and bicarbonate 27. His fasting serum glucose is 80 and creatinine 1.2. His serum osmolality is 343. Which of the following hormone deficiencies is most likely present in this pt?
a) prolactin
b) oxytocin
c) insulin
d) growth
e) antidiuretic
e: This pt’s symptoms and labs are consistent with diabetes insipidus. This condition results from a deficiency of ADH causing polyuria and polydipsia.
A 42yo woman has experience recent weight gain, heavy periods, fatigue, cold intolerance, and constipation. She has a rough voice, and her rate of speech is slow. Physical exam is significant for an enlarged thyroid, slow reflexes, and the presence of brittle and course hair. She denies any hx of bipolar disease or tx with lithium. Lab tests show an elevated TSH and low free T4 (FT4). What is the most appropriate tx for this pt?
a) propylthiouracil (PTU)
b) levothyroxine
c) surgical resection
d) radioiodid ablation
b: The pt’s signs and symptoms are consistent with hypothyroidism. Tx of choice is levothyroxine, which is partially converted in the body to T3. Significant increases are seen within 1-2 weeks, with max levels reached in 3-4 weeks.
A 22yo man is being evaluated for extremity enlargement unlike anyone in his family. Over the past 2 years, he has noticed that his rings no longer fit and his feet are so wide that he cannot find shoes to fit. He has always been tall for his age, greater than the 95th percentile throughout his teenage years. He has very coarse facial features, macroglossia, and a very deep voice. What is the most likely cause of this patients condition?
a) adrenal neoplasm
b) multi nodular goiter
c) pituitary macroadenoma
d) Rathke cleft cyst
e) testicular neoplasm
c: This pts signs and symptoms are consistent with acromegaly, which is caused by an increased secretion of GH. These are almost always caused by pituitary macroadenomas. The tumors may be locally invasive into the cavernous sinus but are typically not malignant.
A 49yo man presents to the office complaining of general malaise with muscle aches, anorexia, fever, and severe pain over his anterior neck radiating to his ears. He state that he was ill about 2 weeks ago with a sore throat**, but it resolved within a few days. On palpation, the thyroid gland is enlarged and tender. His lab workup shows a high T4 level and increased ESR. What is the most appropriate therapy for this pt’s disease?
a) levothyroxine sodium
b) PTU therapy
c) radioiodine ablation
d) surgery
e) supportive therapy only
e: This is a subacute, painful thyroiditis. This is a self-limiting disorder that at most requires symptomatic therapy. In mild cases, analgesics (ASA) are sufficient for pain relief and to decrease the inflammation. Prednisone may bring more relief if needed. Transient hypothyroidism should be treated as well.
A 45yo woman presents with weight gain, fatigue, dry skin, and oligomenorrhea. On physical exam, the pt has a palpable thyroid mass over the right lobe. An ultrasound evaluation of the thyroid shows diffuse heterogenous enlargement of the gland. Which of the following is the most likely dx?
a) Multinodular goiter
b) thyroid carcinoma
c) thyroid adenoma
d) Hashimoto thyroiditis
d: Hashimoto thyroiditis is an autoimmune disorder of the thyroid gland. This condition causes hypOthyroidism. ON physical exam, a goiter may be palpated. In order to distinguish this from other conditions, lab and diagnostic studies should be done. When an ultrasound is performed, it will show diffuse heterogenous enlargement of the gland and not a solitary or multi nodular gland.
A 23yo pt with type 1 DM has been having difficulty sleeping at night. Usually around 3am the pt will wake up feeling sweaty, nauseated, and tachycardia. HE has recorded the following blood glucose levels: 10pm=90mg/dL; 3am=40mg/dL; 7am=200mg/dL What is the best advice for this pt? a) stop eating a bedtime snack b) increase the evening regular dosage c) decrease the evening Lente dosage d) exercise before going to bed at night
(don’t think we need to know this?)
c) The patient has described the Somogyi effect. This effect occurs because the pt is receiving too much intermediate insulin at dinner time. This occurs when nocturnal hypoglycemia results in counter-regulatory hormones producing hyperglycemia. Either the intermediate insulin dosage can be shifted to a lower does at bedtime or the pt can eat a larger snack at bedtime.
A 47yo woman presents to the office with increased BP, bradycardia, constipation, muscle cramps, and weight gain. What is the best initial lab workup for this pt?
a) TSH level
b) T3 & T4
c) Free T4 & TSH
d) serum thyroglobulin
e) RAI uptake and thyroid scan
c: This pt is displaying symptoms of hypOthyroidism. The most appropriate tests to differentiate the cause for this are free T4 and TSH. Serum T3 is not a sensitive test for hypothyroidism
An obese pt with T2DM is started on initial therapy to improve glycemic control. Which of the following would be c/i for the tx with metformin?
a) renal failure
b) history of ketoacidosis
c) inflammatory bowel disease
d) anemia
a: Metformin should NOT be used in pts with renal insufficiency due to its ability to produce LACTIC ACIDOSIS. Other c/i include liver disease, severe CHF, metabolic acidosis, or hx of alcohol abuse.
A 45yo man with a hx of neck irradiation for Hodgkin lymphoma at the age of 15 is found to have a 1.5cm, non-tender, firm thyroid nodule. Upon lab evaluation, the pt is found to be euthyroid, and a FNA bx reveals malignancy. What histologic type is most likely?
a) anapestic
b) follicular
c) medullary
d) papillary
d: Thyroid carcinoma often presents as an asymptomatic thyroid nodule. The most common histological form is PAPILLARY carcinoma, representing more than 80% of cases.
A 25yo mn presents to the clinic complaining of nocturnal enuresis, weight loss, and blurred vision. On further questioning, he relates that he has increased appetite and thirst. His fasting blood glucose level is 225mg/dL. Which of the following would be indicative of type 1 vs type 2 diabetes mellitus?
a) increased Triglycerides
b) presence of glutamic acid decarboxylase
c) presence of C-peptide
d) decreased urine catecholamines
b: T1DM is an autoimmune disease. New onset type 1 diabetic pts have islet antibodies. A variety of beta-cell antibodies including insulin and glutamic acid may exist. GAD 65 is present in 70-90% of pts with new onset T1DM
A 54yo man with T2DM has a BP of 146/92 and 138/90 on two separate occasions. Which of the following treatments offers the best outcomes to reduce cardiovascular complications of disease?
a) lifestyle modification
b) calcium channel blockers
c) diuretics
d) ACE inhibitors
d: The importance of aggressive BP management in diabetes is important in decreasing cardiovascular microvascular complications of diabetes. The JNC 7 report has established BP targets of less than 130/85. Beta blockers and ACE inhibitors have both been effective in reducing cardiovascular and microvascular complications of diabetes. Because of the results of several large trials, ACE inhibitors are recommended as first line anti-HTN therapy in diabetic pts with HTN.
A 68yo woman complains of loss of appetite, weakness, fatigue, constipation, and impaired memory. She has a hx of two episodes of nephrolithiasis. Lab evaluation reveals calcium levels and PTH are high. Which of the following is a common manifestation of this disease?
a) anxiety
b) bone fractures
c) heart failure
d) hirsutism
e) proximal muscle weakness
b: This pt has hyperparathyroidism. The most common clinical manifestation of disease is nephrolithiasis due to elevated levels of PTH. There is a high rate of bone fractures in patients with PTH due to increases osteoclastic and osteoblastic activity.
63yo woman present with shortness of breath, cough, and proximal muscle weakness of 1 month duration. On clinical exam, she is noted to have a BP of 156/102, facial flushing, mild hirsutism, truncal obesity, marked proximal muscle weakness of both the upper and lower extremities, and hyper pigmentation over the palms and back of the neck. Lab exam reveals hypercortisolism and increased ACTH. Which of the following would be the most likely dx in this patient?
a) lymphoma
b) ovarian cancer
c) renal cell carcinoma
d) small cell lung carcinoma
d: Tumor cells may secrete hormones that have the same biologic actions as the normal hormone. This pts symptoms are consistent with adrenocorticoid hyper function. The most common cause of ectopic ACTH syndrome is SMALL CELL LUNG CARCINOMA*. This should be suspected in any patient with risk factors for lung cancer.
