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Back Pain in a 22-Year-Old Man

A 22-year-old man was referred for evaluation of insidious onset of thoracic pain of 6 weeks duration. He recently had been stationed in southern California. Before presentation, he had fatigue, a nonproductive cough, dyspnea on exertion, and constant chest pain that radiated to the thoracic spine. He also described persistent axial back pain and some difficulty with walking. He denied any change in his bowel or bladder function. His medical history was noncontributory because he had been in his usual state of good health until the onset of symptoms. His surgical history was significant only for an appendectomy at the age of 12 years. On review of systems, he described some difficulty swallowing, muscle weakness, night sweats, and a 45-lb weight loss during the preceding several months. Physical examination revealed an ill-appearing man in no acute distress. The spine was nontender to palpation, yet he did have some tenderness to palpation along the paraspinal muscles in the upper thoracic spine. Neurologic examination showed normal strength and sensation of the upper and lower extremities. Patellar and Achilles tendon reflexes were hyperreflexic bilaterally. A positive Babinski sign and five to six beats of clonus also were present bilaterally. Gait evaluation showed ataxia with tandem walking while heel to shin testing was normal. Laboratory evaluation revealed a leukocyte count of 7300/mm (normal, 4800–10,800/mm), an erythrocyte sedimentation rate of 78 mm per hour (range, 0–15 mm per hour), and a C-reactive protein of 17.92 mg/dL (normal, 0.03–5.00mg/dL). Radiographs (Fig 1) andMRI scans of the cervical and thoracic spine (Fig 2) were obtained for additional evaluation. Based on the history, physical findings, and imaging studies, what is the differential diagnosis? CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Number 415, pp. 319 – 328 B 2003 Lippincott Williams & Wilkins, Inc.