Hepatitis B reactivation after oral capecitabine treatment in a rectum cancer patient with isolated anti-HBc IgG positivity.

Introduction: Hepatitis B virus (HBV) reactivation in the setting of chemotherapy and immunosuppressive therapy is associated with significant morbidity and mortality. Herein we present a case of HBV reactivation after oral capecitabine treatment in a patient with rectum cancer and isolated anti-HBc IgG positivity.

Case Report: A 57-year-old man was consulted from the oncology clinic because of increased serum liver tests after chemotherapy. He underwent surgery for early-stage rectal cancer and received adjuvant chemotherapy with oral capecitabine. After cessation of chemotherapy, his laboratory tests revealed severe liver dysfunction. HBV markers showed positivity for hepatitis B surface antigen (HBsAg) and hepatitis B core antibody (anti-HBc). HBV DNA level was markedly elevated.

Management And Outcome: A review of medical records revealed that, before chemotherapy, the patient was positive for anti-HBc IgG but negative for HBsAg, and serum aminotransferases were within the normal limits. A diagnosis of HBV-related hepatitis due to capecitabine use was made, and the patient was put on tenofovir treatment. Six months later, HBV DNA decreased, and liver function tests were normalized.

Discussion: To the best of our knowledge, this is the first case report describing HBV reactivation after chemotherapy with capecitabine for rectal cancer in a patient with isolated anti-HBc IgG positivity. Our case shows that HBV reactivation may develop in a low-risk patient with a low degree of immunosuppression.