ABSTRACT
An 81-year-old woman was treated with Daclatasvir (DCV) and Asunaprevir (ASV) for chronic HCV infection. Although she developed a fever 13 days after treatment initiation, the administration of these drugs was continued under careful observation. After 33 days of treatment initiation, she developed a high fever and hip joint pain that led to hospitalization. Following MRI studies and examination of her hip joint fluid, we suspected that she had developed hip joint synovitis secondary to the use of DCV and ASV. Consequently, we discontinued the administration of both DCV and ASV, resulting in an immediate improvement in her symptoms. Eventually, she attained a sustained virological response 24 despite discontinuing the administration of DCV and ASV. Hence, unexpected adverse events, such as hip joint synovitis, should be considered in the differential diagnosis, particularly in elderly patients (≥80 years) who are treated with DCV and ASV for chronic HCV infection.