| A rare combined T and B cell immunodeficiency with a predisposition to lymphoproliferative syndrome. It is characterized by persistent symptomatic Epstein-Barr viremia and hypogammaglobulinemia variably presenting with fever, lymphadenopathy and systemic inflammatory conditions including hepatitis, pneumonia and sepsis. It may be associated with lymphoma, hemophagocytic lymphohistiocytosis, and aplastic anemia. |