Abstract
Adefovir dipivoxil is a commonly used antiviral agent for the treatment of chronic hepatitis B. Dose-related nephrotoxicity is reported and can definitely occur at daily dosages of >30 mg. We present a case of generalized intractable pain in a patient with chronic hepatitis B treated with adefovir dipivoxil for 5 years. A 42-year-old man complained of a 7-month history of generalized bone pain involving his knees, ankles, and low back. His severe pain was indicated by a visual analog scale value of 100 mm. Laboratory results showed renal tubular dysfunction, elevated serum alkaline phosphatase levels, and hypophosphatemia, and his calculated tubular phosphate reabsorption rate was reduced at only 5.2%. Radiologic examinations showed osteomalacia with multiple bone fractures. These results suggested a diagnosis of Fanconi's syndrome with osteomalacia. After discontinuation of adefovir dipivoxil, his symptoms improved, and his visual analog scale value recovered to 17 mm. Calculated tubular phosphate reabsorption rate recovered to 82.4% at 4 months after adefovir cessation.
