1Clinical Immunology and Allergy, Allergy Research Center
2Department of Pediatrics, Division of Immunology and Allergy, Namazi Hospital, Shiraz University of Medical Sciences, Shiraz
3Department of Clinical immunology and Allergy, Mashhad University of Medical Science , Mashhad, Iran
Major histocompatibility complex (MHC) class II deficiency is a primary immunodeficiency disease characterized by abnormality of MHC class II molecules surface expression on peripheral blood lymphocytes and monocytes. Clinical manifestations include extreme susceptibility to viral, bacterial, and fungal infections but the immunodeficiency is not as severe as SCID (severe combined immunodeficiency), as evidenced by failure to develop disseminated infection after BCG vaccination. Therefore, MHC II deficiency with BCGosis, that is disseminated BCGitis, is not reported commonly. We report an interesting case of BCGosis after vaccination that was diagnosed to have probable MHC II deficiency.