Myopathy in thiamine deficiency: analysis of a case.

BACKGROUND Tenderness in the limb muscles has been reported anecdotally in patients with beriberi neuropathy, but clinical effects of thiamine deficiency on skeletal muscle have received little attention. OBJECTIVE To describe a patient with thiamine deficiency who manifested myopathic symptoms and responded well to thiamine supplementation. PATIENT A 26-year-old woman with neuropathy and heart failure associated with thiamine deficiency also complained of myalgia and weakness, most troublesome in the proximal portions of the limbs. RESULTS Serum creatine kinase, myoglobin, and aldolase concentrations were abnormally elevated. Magnetic resonance imaging of lower limb muscles demonstrated areas of high signal intensity in T2-weighted images and showed Gd-DTPA enhancement. A biopsy specimen from the quadriceps muscle showed myopathic changes without neurogenic changes. Abnormalities improved well with thiamine administration. CONCLUSION Myopathy may occur in patients with thiamine deficiency.