Hypophosphatemic Osteomalacia after Low-Dose Adefovir Dipivoxil Therapy for Hepatitis B

A 40-yr-old male presented with a 5-month history of bone pain involving both knees, ankles, and several ribs with no antecedent trauma. He had an antalgic gait, tenderness involving the bony margins of both knees, but no synovitis. He had a history of chronic hepatitis B infection, receiving lamivudine at a daily dose of 100 mg for 43 months and adefovir dipivoxil (adefovir) at a daily dose of 10 mg for the past 29 months. He had been receiving...