Endocrinology Flashcards
Regarding routine thyroid hormone replacement, what does levothyroxine contain?
● A. T3
● B. T4
● C. TSH
● D. TSH and T3
● E. TSH, T3, and T4
B. T4
What is the mineralocorticoid potency of dexamethasone?
● A. 0
● B. 1 +
● C. 2 +
● D. 3 +
● E. 5 +
A. 0
Posterior pituitary hormones—ADH and oxytocin—are synthesized in supraoptic and paraventricular nuclei of the hypothalamus in?
● A. Neuroendocrine neurons
● B. Neuroendocrine glands
● C. Median eminence of pituitary stalk
● D. Tuber cinereum
● E. Parvocellular system
B. Neuroendocrine glands
Corticotropin also called adrenocorticotrophic hormone (ACTH) is a 39 amino acid trophic hormone synthesized from POMC. It has an active half-life of 10 minutes. It produces a diurnal peak in cortisol. When does the highest peak occur?
● A. Early morning
● B. Noon
● C. Afternoon
● D. 11 p.m.
● E. Midnight
A. Early morning
What is the most powerful physiologic stimulus for ADH release?
● A. Increase in serum osmolality
● B. Hypokalemia
● C. Hyponatremia
● D. Hypoglycemia
● E. Pain
A. Increase in serum osmolality
The posterior pituitary (neurohypophysis AKA pars nervosa) derives from downward evagination of neural crest cells (brain neuroectoderm) while the anterior pituitary (adenohypophysis) develops from an upward evagination of epithelial ectoderm of oropharynx. This upward evagination of ectoderm of oropharynx is known as?
● A. Median eminence
● B. Craniopharyngeal duct
● C. Rathke’s pouch
● D. Remnants of Rathke’s pouch
● E. Pars intermedius
C. Rathke’s pouch
The six hormones that are released from anterior pituitary are primarily formed in tuber cinereum nucleus while two hormones (ADH and oxytocin) that are released from posterior pituitary are primarily formed in magnocellular neuroendocrine
neurons in the supraoptic and paraventricular nuclei. Where does these three nuclei reside?
● A. Thalamus
● B. Hypothalamus
● C. Basal ganglia
● D. Median eminence
● E. Both A and B
E. Both A and B
Growth hormone (GH) is under dual hypothalamic control via the hypophyseal portal system. GH releasing hormone from the arcuate nucleus stimulates synthesis and secretion of GH while GH release is suppressed by which of the following?
● A. Ghrelin, a peptide secreted by GI tract
● B. Somatostatin from the periventricular nucleus
● C. Insulin-like growth factor-1 synthesized by liver
● D. Somatomedin-C
● E. A and B
B. Somatostatin from the periventricular nucleus
Antidiuretic hormone (ADH) AKA arginine vasopressin (AVP) is released from posterior pituitary gland into the systemic circulation. It causes increased reabsorption of water in kidneys
and produces concentrated urine. What is the most powerful physiologic stimulus for ADH release?
● A. Reduction of intravascular volume
● B. Activation of thirst center in brain
● C. Increase in serum osmolality
● D. Reduction of water in interstitial spaces
● E. Both A and C
C. Increase in serum osmolality
Physiologic replacement therapy (in the absence of stress) for secondary adrenal insufficiency due to deficient corticotrophin (ACTH) release by pituitary is as follows:
● A. Hydrocortisone 10 mg PO a.m. and 20 mg PO p.m.
● B. Hydrocortisone 20 mg PO a.m. and 10 mg PO p.m.
● C. Hydrocortisone 25 mg PO a.m. and 10 mg PO p.m.
● D. Prednisone 5 mg PO every a.m. and 2.5 mg PO every p.m.
● E. Both B and D
E. Both B and D
A patient presented with fatigue, anorexia, nausea, hypotension, and hypoglycemia in emergency. This patient was previously taking hydrocortisone for a long period for brain edema due to brain tumor, which was stopped abruptly. What is most
likely cause of the symptoms in this patient?
● A. Exacerbation of brain edema
● B. Sudden increase in tumor size
● C. Steroid withdrawal
● D. Thyroid deficiency
● E. All of the above
C. Steroid withdrawal
A patient on prolonged steroid use started developing side effects due to prolonged steroid usage. Following are the side effects of steroid except?
● A. Hypertension
● B. Hypokalemic acidosis
● C. Sodium and water retention
● D. Pseudotumor cerebri
● E. Progressive multifocal leukoencephalopathy
B. Hypokalemic acidosis
A patient on prolonged steroid use develops flu and fever. He developed mental status changes, muscle weakness, and shock. Following are components of treatment of Addisonian crisis except?
● A. Admit the patient in ICU and give fluids for shock and dehydration
● B. Give hydrocortisone sodium (Solu-Cortef) 100 mg IV stat then 50 mg IV every 6 hours
● C. Desoxycorticosterone acetate 5 mg IM BID
● D. Draw serum for cortisol determination
● E. Methylprednisolone 1 g IV stat
E. Methylprednisolone 1 g IV stat
A patient with hypothyroidism has to undergo surgery. 0.05 mg levothyroxine is started in this patient. A few days later the patient developed confusion, lethargy, and hypotension. Which
of the following is the possible cause of development of these symptoms?
● A. Development of symptoms of hypothyroidism
● B. Development of hyperthyroidism
● C. Adrenal insufficiency
● D. Hypercortisolism
● E. Brain damage
C. Adrenal insufficiency
Steroid stress dose on the day of elective surgery is 50 mg cortisone IM followed by 200 mg hydrocortisone IV infused over 24 hours. What is the steroid dose on postoperative day 1?
● A. 100 mg at 8 a.m., 50 mg at 4 p.m.
● B. 50 mg at 8 a.m., 25 mg at 4 p.m.
● C. 50 mg at 8 a.m., 25 mg at 4 p.m., 12.5 mg at 10 p.m.
● D. 50 mg at 8 a.m., 4 p.m., and 10 p.m.
● E. 100 mg at 8 a.m., 50 mg at 4 p.m., 50 mg at 10 p.m.
D. 50 mg at 8 a.m., 4 p.m., and 10 p.m.
