A rare combined T and B cell immunodeficiency with a predisposition to lymphoproliferative syndrome. It is characterized by persistent symptomatic EBV-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. The disease is autosomal recessive lymphoproliferative disease (EFO_0700055). Also known as: CD27 deficiency.