Immunohistochemical techniques improve the diagnosis of myocarditis in cases of suspected sudden infant death syndrome (SIDS)

Immunohistochemical techniques have improved the diagnosis of myocarditis. In a post mortem study, eight specimens in each case of the formalin-fixed and paraffin-embedded hearts of 20 suspected cases of sudden infant death s yndrome (SIDS) were investigated with traditional hematoxylin-eosin stainin g and immunohistochemical methods. The hematoxylin-eosin stained specimens were examined for myocarditis according to the Dallas criteria; only in one case was a myocarditis diagnosed. The subsequent definition of the major h istocompatibility complex class II antigens (HLA-DP,DQ,DR and HLA-DR), know n to be enhanced in cases of myocarditis, the quantification of leucocytes with leucocyte common antigen (LCA) and characterization and quantification of T-lymphocytes using a specific marker (CD-3) allowed the definite diagn osis of myocarditis in three additional cases, six cases were found with mo derate changes and ten cases without signs of inflammation. (C) 1999 Elsevi er Science Ireland Ltd. All rights reserved.