Endocrine III Flashcards
What is the likely diagnosis in a patient taking risperidone that presents with fatigue and headache with low TSH/LH and mildly elevated prolactin on laboratory exam?
Non-functioning (gonadotroph) pituitary adenoma
presence of hypopituitarism (e.g. hypothyroidism, hypogonadism) helps distinguish pituitary adenoma from medication side effect
What is the likely diagnosis in a patient that develops pallor, tachycardia, and severe hypertension without fever after induction of anesthesia? The patient has a history of frequent headaches and hypertension.
Pheochromocytoma
episodes of pheochromocytoma can be precipitated by medications, especially anesthetic agents, and surgical procedures; normal temperature helps differentiate pheochromocytoma from thyroid storm (typically elevated temp.)
What is the likely diagnosis in a patient that develops post-operative high fever, tachycardia, hypertension, and lid lag with no muscle rigidity? Serum creatinine kinase is slightly elevated.
Thyroid storm
typically triggered by a specific event in patients with undiagnosed or inadequately treated hyperthyroidism (e.g. surgery, trauma, infection, CT scan with contrast due to acute iodine load)
What is the likely diagnosis in a patient that presents with constipation, cold intolerance, low libido, and hypoglycemia with eosinophilia on laboratory exam?
Hypopituitarism
patient is experiencing secondary hypothyroidism, secondary adrenal insufficiency, and hypogonadotropic hypogonadism
What is the likely diagnosis in a patient that received multiple blood transfusions and develops paresthesias, carpal spasm, and hyperreflexia?
Hypocalcemia
citrate in transfused blood binds ionized calcium, causing hypocalcemia, especially in patients with impaired hepatic function (decreased clearance of citrate by the liver)
What is the likely diagnosis in a patient with a family history of kidney stones and stomach ulcers that presents with refractory peptic ulcer disease, hypercalcemia, and low serum phosphorus?
MEN1
peptic ulcer disease due to gastrinoma (ZE syndrome); hypercalcemia/low phosphorus due to hyperparathyroidism
What is the likely diagnosis in a patient with a long history of Hashimoto thyroiditis that develops a rapidly enlarging, firm goiter with dysphagia, hoarseness, and fever?
Thyroid lymphoma
patients can exhibit “B symptoms” (e.g. night sweats, weight loss, fever), as well as symptoms of retrosternal extension (e.g. dysphagia, hoarseness); may also have facial plethora and cyanosis when raising the arms above the head due to compression of the subclavian vein and IJV between the clavicle and thyroid (Pemberton sign)
What is the likely diagnosis in a patient with a malignant thyroid nodule, elevated calcitonin, and a family history of thyroid cancer?
MEN2 (A or B)
elevated calcitonin is suggestive of medullary thyroid carcinoma
What is the likely diagnosis in a patient with a pituitary mass and the laboratory values below?
Prolactin: 250 ng/mL (normal, < 15)
LH: low
TSH: normal
Prolactinoma
most common primary pituitary tumor; low LH due to inhibition of GnRH by prolactin
What is the likely diagnosis in a patient with a pituitary mass and the laboratory values below?
Prolactin: 45 ng/mL (normal, < 15)
LH: low
TSH: low
Non-functional (gonadotroph) pituitary adenoma
mild elevation in prolactin due to compression of dopaminergic pathways; low LH/TSH due to compression of thyrotrophs and gonadotrophs
What is the likely diagnosis in a patient with an acute MI complicated by cardiogenic shock that develops a low total T3 level despite normal TSH/free T4?
Euthyroid sick syndrome (low T3 syndrome)
thought to result from decreased peripheral 5’-deiodination of T4; any patient with an acute, severe illness can have abnormal TFTs
What is the likely diagnosis in a patient with celiac sprue that develops diffuse bone pain, muscle weakness, and the laboratory results below?
Ca2+: normal
Phosphate: low
PTH: high
Alkaline phosphatase: high
What is the likely diagnosis in a patient with celiac sprue that develops diffuse bone pain, muscle weakness, and the laboratory results below?
Ca2+: normal
Phosphate: low
PTH: high
Alkaline phosphatase: high
Osteomalacia
What is the likely diagnosis in a patient with flushing, diarrhea, wheezing, and a heart murmur that increases with inspiration?
Carcinoid syndrome
What is the likely diagnosis in a patient with flushing, watery diarrhea, hypokalemia, and achlorhydria?
VIPoma
i.e. WDHA syndrome; typically involves the pancreatic tail (abdominal imaging can localize the tumor)
What is the likely diagnosis in a patient with headaches, weight loss, intermittent palpitations, and visual disturbances? Laboratory exam reveals elevated T3/T4 and TSH.
TSH-secreting pituitary adenoma
inappropriately normal or elevated TSH with elevated T3/T4 helps rule out TSH-independent hyperthyroidism (e.g. Grave’s disease)
What is the likely diagnosis in a patient with hypercalcemia, elevated PTH, and high urine Ca2+?
Primary hyperparathyroidism
high urine Ca2+ helps distinguish from familial hypocalciuric hypercalcemia
What is the likely diagnosis in a patient with increasing polyuria/polydipsia with hypernatremia, high serum osmolality, and low urine osmolality?
Diabetes insipidus
serum Na+ > 145 mEq/L with dilute urine excludes primary polydipsia and favors diabetes insipidus
What is the likely diagnosis in a patient with increasing polyuria/polydipsia with hyponatremia, low serum osmolality, and low urine osmolality?
Primary polydipsia
serum Na+ < 137 mEq/L with dilute urine favors primary polydipsia and excludes diabetes insipidus
What is the likely diagnosis in a patient with low urine osmolality that does not improve significantly following water deprivation and administration of desmopressin?
Nephrogenic diabetes insipidus
What is the likely diagnosis in a patient with low urine osmolality that improves by > 50% following administration of desmopressin?
Central diabetes insipidus
What is the likely diagnosis in a patient with low urine osmolality that improves to > 600 mOsm/kg after 2-3 hours of water deprivation?
Primary polydipsia
What is the likely diagnosis in a patient with weight loss, tachycardia, anti-thyroid peroxidase antibodies, and the physical exam findings below?
Thyroid gland: normal size, non-tender
TSH: low
Free T4: high
Radioactive iodine uptake: < 5%
What is the likely diagnosis in a patient with weight loss, tachycardia, anti-thyroid peroxidase antibodies, and the physical exam findings below?
Thyroid gland: normal size, non-tender
TSH: low
Free T4: high
Radioactive iodine uptake: < 5%
Painless (silent) thyroiditis
painless thyroiditis is often a self-limited hyperthyroid phase of Hashimoto thyroiditis
What is the likely diagnosis in a patient with weight loss/tachycardia and a diffusely tender thyroid with low TSH and high free T4?
Subacute (de Quervain) thyroiditis
typically follows an upper respiratory infection; treatment is symptomatic (e.g. NSAIDs, beta-blockers)
What is the likely diagnosis in a patient with well-controlled diabetes that develops diarrhea, weight loss, anemia, and erythematous plaques with central clearing?
Glucagonoma
rash is consistent with necrolytic migratory erythema; glucagonoma diagnosis confirmed with glucagon levels > 500 pg/mL
What is the likely diagnosis in a tall patient with kyphoscoliosis, neuromas on the lip/tongue, and medullary thyroid cancer?
MEN 2B
pheochromocytoma may be initially asymptomatic; MEN2A and MEN2B are associated with RET mutations
What is the likely diagnosis in a young female with irregular menses, hirsutism, and elevated serum testosterone with no abdominal striae?
Polycystic ovary syndrome
What is the likely diagnosis in a young patient with hypertension that develops severe hypokalemia after beginning a low-dose thiazide diuretic?
Primary hyperaldosteronism
patients with mild primary hyperaldosteronism are prone to developing diuretic-induced hypokalemia; other findings include metabolic alkalosis and mild hypernatremia
What is the likely diagnosis in a young patient with nausea/vomiting, weight loss, and polydipsia? Laboratory exam is significant for low HCO3- and high blood glucose/K+ levels.
Diabetic ketoacidosis
What is the likely diagnosis in a young woman that develops amenorrhea, weight gain, hypertension, hirsutism, muscle weakness, and easy bruising?
Cushing syndrome
Cushing syndrome may be similar in presentation to PCOS (obesity, hirsutism, amenorrhea), but PCOS does not cause muscle weakness nor easy bruisability
What is the likely diagnosis in an elderly diabetic patient that develops weakness and blurred vision after a viral URI with a markedly elevated serum glucose (> 1000 mg/dL) on laboratory exam?
Hyperosmolar hyperglycemic state
frequently presents with severe hyperglycemia and increased serum osmolality without acidosis/ketonemia
What is the likely diagnosis in an obese young woman that presents with male-pattern baldness, excessive acne, and amenorrhea?
Polycystic ovarian syndrome
What is the likely diagnosis in an older patient with significant smoking history that presents with hypercalcemia and low PTH?
Humoral hypercalcemia of malignancy
due to secretion of PTHrP from squamous cell lung cancer
What is the likely etiology of hyperthyroidism in a patient with a normal sized thyroid, diffusely decreased radioactive iodine uptake, and low serum thyroglobulin?
Exogenous hormone
low RAIU suggests release of preformed hormone or exogenous hormone intake; low thyroglobulin helps differentiate exogenous hormone intake from thyroiditis (high thyroglobulin)
What is the likely etiology of hyperthyroidism in a patient with elevated free T3/T4, low TSH, and the radioactive iodine scan below?
Toxic adenoma
due to autonomous thyroid hormone production
