Severe Evans syndrome with multi-system involvement is a distinct immunodeficiency disorder.

A female infant who presented with autoimmune hemolytic anemia and thrombocytopenia subsequently developed hepatic, dermatologic, renal, pulmonary, gastrointestinal, endocrine, and nervous system involvement. Prolonged and intensive treatment with prednisone, IVIG, mycophenolate mofetil, and anti-CD20 and anti-CD52 antibodies was necessary to control the symptoms. Laboratory evaluation showed normal lymphocyte subsets and function. There was normal Foxp3 and CD25 expression, no increased CD4(-)CD8(-) T-cell population, and the AIRE and Fas genes were without mutations. These features place the patient at the most severe portion of the Evans syndrome spectrum, and suggest that this case may represent a rare, new immunodeficiency disorder.