USMLE® Step 1 style questions USMLE
A 65 year-old man comes to his primary care physician because of lower back pain, recurrent sinus infections, and 4 kg (8.8 lb) unintentional weight loss over the past three months. Past medical history is notable for osteoporosis and atherosclerosis. The patient consumes 4-5 glasses of wine per week and is sexually active with his spouse. His temperature is 36.8°C (98.2°F), blood pressure is 125/76 mmHg, pulse is 65/min, and respiratory rate is 15/min. Cardiac, pulmonary, and abdominal exams are normal. Pain is elicited with palpation of the lumbar spine. As part of the diagnostic work-up, a peripheral blood smear is ordered, and the results are as follows:
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Which of the following findings will provide a definitive diagnosis of the patient’s condition?
Multiple myeloma is a type of cancer that affects the plasma cells in the bone marrow. It is characterized by an overgrowth of abnormal plasma cells, which can cause damage to the bones, weaken the immune system, and produce an excess of certain proteins in the blood. Symptoms of multiple myeloma may include bone pain, fatigue, anemia, kidney problems, and frequent infections.