A preliminary immunohistochemical study of fibronectin in viral myocarditis

For postmortem diagnosis of viral myocarditis, 12 specimens of heart in autopsy were studied immunohistochemically with anti-fibronectin(FN) antibody. Among 5 cases with definite or suspected myocarditis, intensive FN-positive could be found in all monocytes, macrophages and some neutrophils and there were 3 cases with FN-positive cardiomyocytes. While in 3 violent death cases with leucocytes infiltration in the interstitial tissue of myocardia, no FN-positive cardiomocytes were observed, which was the same as that of 4 case without cardiac pathological changes. Moreover, there were rarely FN-positive leucocytes in the 7 cases without viral myocarditis. The results suggest that the immunohistochemical observation of FN in myocardia might be of value for detecting slight degeneration of cardiomyocytes and determining the inflammatory leucocyte infiltration in myocarditis.