A 46-year-old woman comes to the office with a 3-week history of back pain. She has experienced no trauma, focal leg weakness, or incontinence. A compression fracture of the T11 vertebra was found a year ago when she had similar symptoms. At that time, a dual-energy x-ray absorptiometry scan showed a T score of -3.1 at the lumbar spine and -2.0 at the femoral neck. She was prescribed alendronate. The patient has gained about 6.8 kg (15 lb) over the last year and attributes this to a decrease in physical activity following the first compression fracture. She now has difficulty climbing up stairs and standing up from a sitting position. Her last menstrual period was a year ago. Her medical history is significant for diet-controlled diabetes and hypothyroidism. Her other medications include levothyroxine and calcium with vitamin D. The patient has no family history of diabetes or osteoporosis. She does not use tobacco, alcohol, or illicit drugs. Blood pressure is 154/88 mm Hg and pulse is 78/min. BMI is 35 kg/m². Tinea versicolor is noted on skin examination. She has local tenderness at the level of the T8 vertebra. The remainder of the physical examination is normal. Laboratory results are as follows: Thoracic spine radiograph shows a new T8 vertebral compression fracture. Which of the following is the best next step in management of this patient?

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11ec193a_97be_e3f1_853d_db921949644d_MD0002_00 This patient has recurrent vertebral fractures due to osteoporosis as seen on the dual-energy x-ray absorptiometry (DXA) scan. Given her young age and recurrent fractures, she requires further evaluation for secondary causes of osteoporosis. Her laboratory studies and clinical history show no evidence of kidney disease, vitamin D deficiency, hyperparathyroidism (normal serum and urine calcium), or thyroid disease. However, she has features that suggest Cushing's syndrome, including weight gain, diabetes mellitus without a family history of diabetes, proximal muscle weakness, elevated blood pressure, fungal skin infection, amenorrhea, and hypokalemia. The elevated cortisol levels in Cushing's syndrome cause bone loss by decreasing intestinal calcium absorption, decreasing bone formation, increasing bone resorption, and decreasing renal calcium reabsorption. Patients with suspected Cushing's syndrome should have initial evaluation with overnight dexamethasone suppression test, 24-hour urinary free cortisol assay, or late-night salivary cortisol measurement. (Choice A) Calcitonin can be used to relieve pain from acute osteoporotic vertebral fractures. However, nonsteroidal anti-inflammatory drugs and acetaminophen are preferred for initial management. Also, adding calcitonin to alendronate does not provide additional benefit for bone density or fracture prevention. (Choice B) Celiac disease may cause malabsorption and lead to osteoporosis, but it usually presents with iron deficiency anemia, vitamin D deficiency, and low urinary calcium excretion. This patient's normal laboratory studies (hemoglobin, vitamin D, urinary calcium) make this unlikely. (Choice C) Bone marrow biopsy is indicated in patients with osteoporosis and suspected multiple myeloma. However, this patient's absence of anemia and monoclonal spike on serum protein electrophoresis make this unlikely. (Choice E) Teriparatide is a bone anabolic agent used as a second-line treatment option for severe osteoporosis refractory to bisphosphonate therapy. Changing over to intravenous bisphosphonate or subcutaneous teriparatide should be considered only after secondary causes of osteoporosis have been ruled out. Educational objective: Early onset of severe osteoporosis and recurrent fragility fractures require evaluation for secondary causes of osteoporosis. __________ References: Bone mineral density, prevalence of vertebral fractures, and bone quality in patients with adrenal incidentalomas with and without subclinical hypercortisolism: an Italian multicenter study. (http://www.ncbi.nlm.nih.gov/pubmed/19549741) Clinical considerations in premenopausal osteoporosis. (http://www.ncbi.nlm.nih.gov/pubmed/15037488)

A 46-Year-Old Woman Comes to the Office with a 3-Week