[Suspected SIDS and diagnosis of myocarditis]

During the last years immunohistochemical techniques have improved the diagnosis of myocarditis using specific markers for quantification of leucocytes and characterization of T-lymphocytes together with the definition of MHC class II Antigens (HLA-DP, DQ, DR), known to be enhanced in cases of myocarditis. These techniques allow the diagnosis of myocarditis in an early stage of the inflammatory process in contrast to the conventional diagnostic with hematoxylin-eosin.

20 autopsy cases were examined in a retrospective study with conventional histological and immunohistological methods. After routine investigations including toxicological and histological examination of internal organs all cases were considered as cases of Sudden Infant Death Syndrome (SIDS).

Increased number of LCA-positive leucocytes and CD-3-positive T-lymphocytes together with enhanced expression of inflammatory marker leads to the diagnosis of a lymphomonocytic myocarditis in three cases, in one case myocarditis could be diagnosed by conventional hematoxylin-eosin staining. In one of these four cases of myocarditis a positive immunohistochemical reaction was found using a new antibody against enteroviruses.

Immunohistochemical techniques improve diagnosis of myocarditis in cases of suspected sudden infant death syndrome. Further studies using immunohistochemical inflammatory markers to control the incidence of acute myocarditis are necessary.