RESUMO
Familial erythrophagocytic lymphocytosis (FEL) is a rare, nonmalignant class II histiocytosis characterized by fever, irritability, hepatosplenomegaly, pancytopenia, and hemophagocytosis. Various chemotherapeutic regimens have had mixed success, with the only curative therapy being bone marrow transplantation. We report our experience with two children whose therapy with etoposide and steroids failed. They were successfully treated and had durable remissions with cyclosporine A (CSA). We propose that in FEL there may exist abnormal interactions between antigen-presenting cells and T-lymphocyte subsets, and that CSA may down-modulate this aberrant response. The use of a low-dose CSA regimen may represent a treatment option that should be further explored.