Large granular lymphocyte leukemia (LGL) in a child with hyper IgM syndrome and autoimmune hemolytic anemia

We describe a female with a history of autosomal recessive hyper‐IgM (HIGM) syndrome along with a history of autoimmune hemolytic anemia and intermittent lymphadenopathy. She subsequently developed neutropenia, lymphocyostosis and mild thrombocytopenia. Flow cytometry of the peripheral blood revealed the presence of a marked predominance of cytotoxic T lymphocytes, shown to be clonal, with concomitant natural killer (NK) antigen expression. She responded to weekly methotrexate therapy. Pediatr Blood Cancer 2008;50:142–145. © 2006 Wiley‐Liss, Inc.