CHARACTERIZATION OF COXSACKIE-B VIRUS-RNA IN MYOCARDIUM FROM PATIENTSWITH DILATED CARDIOMYOPATHY BY NUCLEOTIDE SEQUENCING OF REVERSE TRANSCRIPTION-NESTED POLYMERASE-CHAIN-REACTION PRODUCTS

This study was performed to detect and characterize the enterovirus pr esent in myocardium of some patients with heart muscle disease by nucl eotide sequencing of polymerase chain reaction (PCR) products after am plification with enterovirus group-specific primers. Enterovirus seque nces have been detected previously in myocardium of patients with myoc arditis or dilated cardiomyopathy and seem causal, although the partic ular virus serotypes involved have not been identified. In a prospecti ve study of endomyocardial biopsy specimens from 35 consecutive patien ts with suspected heart muscle disease, enterovirus sequences from the 5' nontranslated region were amplified by reverse transcription-neste d PCR using group-specific primers. This region contains both conserve d and variable sequence motifs, characteristic of particular enterovir us serotypes. The nucleotide sequences of individual PCR products were determined by cycle sequencing and compared with all known sequences (GenBank/EMBOL), using the GCG software package. Endomyocardial biopsy specimens from 9 of 21 (42.9%) patients with a histologically confirm ed diagnosis of dilated cardiomyopathy were positive for enterovirus b y PCR, compared with only 1 of 14 (7.1%) patients with other myocardia l pathological conditions (Fisher's exact probability = 0.0275: odds r atio = 9.75; 95% confidence interval = 1.31-72.78). The nucleotide seq uence of the PCR products differed, indicating no cross-contamination. However, computerized comparison showed that each had greatest homolo gy with the 5' nontranslated region of Coxsackie B virus but contained up to 11% sequence variations compared with the prototype Coxsackie B 3 strain Nancy. Parallel investigation of tissue from our mouse model of Coxsackievirus BS-induced myocarditis showed that nucleotide sequen ce changes are not introduced by reverse transcription or PCR. These d ata support the link between enteroviral infection and dilated heart m uscle disease and suggest that Coxsackie B serotypes are the enterovir uses most frequently involved. HUM PATHOL 29:578-584. Copyright (C) 19 98 by W.B. Saunders Company.