Hemophagocytic lymphohistiocytosis in 2 pediatric patients secondary to hepatitis A virus infection.

Hemophagocytic lymphohistiocytosis (HLH) is a rare clinical syndrome characterized by uncontrolled activation of cytotoxic T cells and antigen-presenting cells. Common clinical manifestations include high fever, maculopapular rash, neurological symptoms, coagulopathy, and abnormal liver function tests [1]. HLH can be either primary, that is, due to an underlying genetic defect, or secondary, associated with malignancies, autoimmune diseases, or infections. The true incidence of secondary HLH is difficult to define. Infection associated HLH are most commonly associated with viral infections mainly of the herpes group, with Epstein-Barr virus (EBV) that is proposed to be the most common cause [2]. Despite the high incidence of hepatitis A virus (HAV) infection in the pediatric population in general, there are few pediatric case reports in the literature about HAV-associated hemophagocytic syndrome [3]. We encountered 2 patients with HAV-associated hemophagocytic syndrome.