Entecavir-Associated Thrombocytopenia: A Case Report and Review of the Pathophysiology, Diagnosis, and Treatment of a Rare but Reversible Cause of Thrombocytopenia

الملخص EN

Drug-associated thrombocytopenia is often unrecognized.

We report a 76-year-old female with lymphoma who presented with easy bruising and oral bleeding.

She had undergone screening for hepatitis B virus (HBV) prior to starting rituximab and was found to have hepatitis B core serum antibody (IgG anti-HBc).

She was therefore treated with prophylactic entecavir 0.5 mg daily to prevent reactivation of HBV.

Her initial platelet count was 136,000/mm3.

Five days after starting entecavir, she presented with bruising and oral bleeding and was found to have a platelet count of 7,000/mm3.

A coagulation profile and the rest of the blood parameters (RBC and WBC counts) were normal.

Entecavir was stopped, and she was given 3 units of apheresed platelets followed by intravenous immunoglobulin (1 g/kg) for 5 consecutive days.

Her platelet counts improved and normalized in one week.

She was diagnosed with entecavir-induced thrombocytopenia based on the temporal relationship and after carefully excluding alternate causes of thrombocytopenia.

This case highlights the importance of recognizing drug-induced thrombocytopenia (DITP) as a reversible cause of thrombocytopenia.