A new disorder of lymphocyte apoptosis: combination of autoimmunity, infectious lymphadenopathy, double negative T cells, and impaired activation-induced cell death.

A new symptom-complex is described characterized by manifestations of autoimmune disease, infectious lymphadenopathy, double negative T cells, and impaired activation-induced cell death that developed in late adolescence. Similarities, but also significant differences, to autoimmune lymphoproliferative syndromes (ALPS, Canale-Smith syndrome) and autoimmune lymphoproliferative disease (ALD, Dianzani syndrome), were observed. The main clinical features were recurrent bacterial infections with subsequent lymphadenopathy due to autoimmune neutropenia. Laboratory results revealed a large proportion of alphabetaTCR positive, CD4 negative, CD8 negative, peripheral T cells, and a decreased apoptosis upon activation with phytohemagglutinin and interleukin 2, but normal Fas-mediated apoptosis. Genetic investigations excluded mutations in Fas gene death domain and in the 4 exons of Fas ligand gene. Despite unknown pathogenesis, this new syndrome might belong to the growing group of diseases with defects in apoptosis.