Hepatitis C-associated
osteosclerosis (HCAO) is a rare disorder characterized by a marked increase in skeletal mass in patients who are infected with hepatitis C virus (HCV). The clinical presentation is an acquired deep bone
pain with increased serum
alkaline phosphatase (ALP) activity. We present a case of a patient with HCAO who was treated with
antiviral therapy. A 42-year-old Japanese man presented with severe, stabbing
pain in his lower limbs. He was diagnosed with
hepatitis C secondary to intravenous
drug use 20 years earlier. Serum biochemical studies revealed markedly elevated ALP activity and
osteocalcin levels. Skeletal radiographs showed diffuse bony
sclerosis with marked cortical thickening in the long bones. The bony findings and clinical symptoms were attributed to HCAO. The HCV
RNA viral load was high and the genotype was 2a. The patient was treated with
peginterferon alfa-2b and
ribavirin for 24 weeks. After 24 weeks of the combination
therapy, the patient had a sustained virological response and clinical remission of bone
pain and a decrease in the level of serum ALP. In conclusion, HCAO was improved by the combination
therapy of
peginterferon alfa-2b and
ribavirin when the patient achieved sustained virological response. It was confirmed that HCAO was one of the extrahepatic manifestations of HCV.