A 61-year-old female is diagnosed with osteoporosis by a screening dual-energy x-ray absorptiometry (DEXA) scan.Which of these is a risk factor for postmenopausal osteoporosis?
Answer(s): B
Risk factors for postmenopausal osteoporosis include cigarette smoking, thinness, early menopause (natural or surgical), nulliparity, northern European heritage, some medications (e.g., glucocorticoids), high alcohol or caffeine intake, low dietary calcium consumption, and a family history of osteoporosis. Dietary calcium and vitamin D supplementation and exercise (preferably weight bearing) are the classic lifestyle changes recommended to prevent or treat osteoporosis. (
A 5-year-old girl presents for evaluation of breast development, history of multiple bone fractures, and vaginal bleeding. Physical examination is notable for "café au lait" spots on her skin, tanner stage 2 breasts, and she appears tall for her age. What is the most likely cause of precocious puberty in this child?
The McCune-Albright syndrome is due to a G-protein mutation in the alpha-subunit that causes constitutive stimulatory activity of the tissues. Affected tissues are autonomously active. McCune- Albright syndrome classically consists of a triad of café au lait skin spots, cystic bone lesions (polyostotic fibrous dysplasia), and autonomous endocrine hyperfunction resulting in sexual precocity. Adominant ovarian cyst develops independent of stimulation by gonadotropins and it secretes estradiol, resulting in sexual precocity and skeletal maturity. Therefore, the finding of elevated estradiol levels and suppressed or undetectable gonadotropins is diagnostic. Affected individuals also may have hyperthyroidism, hypercortisolism, pituitary gigantism, or acromegaly.
A39-year-old obese female presents with irregular menstrual periods, mild acne and hirsutism, and acanthosis nigricans on the nuchal fold, axilla, and intertriginous areas (inner upper thighs). You suspect PCOS.Which of the following laboratory tests would be most important to perform to rule out a likely confounding diagnosis?
Answer(s): A
PCOS is the most common endocrine disorder of reproductive age women. Common symptoms include oligo- or amenorrhea, acne, hirsutism, infertility, and weight gain. Common tests used to support the diagnosis of PCOS include LH to FSH ratio, testosterone, DHEAS, and pelvic ultrasound. Acanthosis nigricans is a raised, velvety, tan skin lesion commonly seen on the back of the neck, in the axilla, and the intertriginous areas. Acanthosis nigricans is associated with hyperinsulinemia and is a sign that the patient is at significant risk for prediabetes and frank diabetes. Up to 30% of patients with suspected PCOS have prediabetes, and 8% are frank type II diabetics. PCOS is a diagnosis of exclusion and requires ruling out other possible confounding diagnoses. Given the obesity and acanthosis nigricans in this patient, a 75-g, 2- hour oral glucose tolerance test would be recommended. Other common confounding diagnoses in patients with PCOS include late-onset congenital adrenal hyperplasia (screened with a serum 17- hydroxyprogesterone), Cushing syndrome (screened with a 24 hour urinary free cortisol, or overnight dexamethasone suppression test), and thyroid disease.
A 17-year-old female presents with primary amenorrhea. On physical examination, she has normal secondary sexual characteristics, scant pubic and axillary hair, and a blind ending vaginal pouch. Apelvic MRI indicates inguinal gonads and no uterus. Her karyotype is 46,XY.Which of the following is the most likely etiology of primary amenorrhea in this patient?
Answer(s): C
Androgen insensitivity is an inherited disease resulting from the lack of functional androgen receptors. Gonadal function is that of normal testicles; however, there is no end-organ effect due to the lack of any functional receptors. Because the gonads produce Müllerian inhibiting substance (MIS), the Müllerian structures regress. Primary amenorrhea is therefore a common cause for presentation to a physician. Normal female secondary sexual characteristics and external genitalia result due to the absence of any effect of endogenous androgens and the production of small, but adequate, amounts of estrogen, mostly from peripheral conversion of androstenedione.
A15-year-old female presents to the emergency room (ER) with acute onset right lower quadrant pain and nausea. She recently became sexually active and is "in the middle" of her menstrual cycle. Physical examination is notable for generalized guarding, rebound, and 8/10 pain in both lower quadrants. A pelvic examination shows no vaginal discharge, a normal appearing cervix, and general pelvic tenderness, but the examination is limited by the patient's guarding. Her complete blood count is notable for a borderline elevated white blood cell (WBC) count, and a urinary -hCG is negative. Pelvic ultrasound shows a 2-cm simple appearing cyst on the right ovary and a mild amount of fluid in the cul-de-sac. Acomputed tomographic (CT) scan cannot definitively visualize the appendix, confirms the presence of a 2-cm cystic structure in the right ovary, and otherwise notes normal anatomy.Which of the following is the most appropriate next step?
Acute pelvic pain is a difficult diagnostic dilemma. An acute abdomen can result from appendicitis, ovarian torsion, ruptured ovarian cyst, ectopic pregnancy, PID, diverticular abscess, and other causes. Misdiagnosis of PID is common and the most likely diagnosis confused with PID is appendicitis. In the setting where the etiology of the acute abdomen is not certain, a laparoscopy is indicated both for diagnostic and, in many cases, therapeutic purposes. A pelvic MRI or serial examinations would further delay the diagnosis. In the case of ovarian torsion or appendicitis, rapid diagnosis and treatment is critical to optimize outcomes.
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