Detection of cytomegalovirus genome by in situ hybridization in paraffin embedded endomyocardial biopsy specimens of viral myocarditis.

Cytomegalovirus (CMV) genes were detected by in situ hybridization in 25 Chinese patients with viral myocarditis (VMC). The positive hybridization signals were found in cardiomyocytes (6 cases, 24%), capillary endothelial cells (4 cases, 16%) and interstitial cells (7 cases, 28%). The difference between VMC and control group (16 cases died of brain trauma and 10 cases of congenital heart diseases was statistically significant. There was no definite pathomorphological relationship between the detection of CMV genes and myocardial lesions. The results suggest that CMV infection may be one of the causes of myocarditis and chronic stimulation of the immune system induced by CMV may be a possible pathogenesis of this disease.