title: Molecular diagnosis of myocarditis and dilated cardiomyopathy in children: clinicopathologic features and prognostic implications.
abstract: Myocarditis is the most common cause of heart failure in children. We investigated viral etiology of myocarditis/dilated cardiomyopathy (DCM) in children and correlated molecular findings with pathologic and clinical data. Polymerase chain reaction (PCR) or reverse transcription (RT)-PCR were used to analyze 59 endomyocardial biopsies from 48 consecutive young (<18 yrs) patients (pts) with clinical and histologic diagnosis of myocarditis and DCM, employing primers designed to amplify specific sequences of various DNA and RNA viruses. Nucleic acids were successfully extracted in 41 pts and viral genomes were found in 20 (49%): 12 out of 26 pts (46%) with myocarditis, 6 out of 13 (46%) pts with DCM, and both patients with endocardial fibroelastosis. Enteroviruses were more common in DCM (72%), whereas adenoviruses and enteroviruses shared the same rate (36%) in myocarditis. The mumps virus genome was detected in the two pts with endocardial fibroelastosis. More diffuse inflammatory infiltrates and myocyte damage as well as more impaired left ventricular end diastolic volume and shortening fraction were noted in viral positive cases. PCR positive pts had a worse outcome, resulting in transplantation or death. Three out of 8 pts with viral myocarditis who underwent cardiac transplantation had recurrent PCR-proven graft viral infection. Viral myocarditis/DCM appeared to be a more severe disease than nonviral forms. Enteroviruses were more common in DCM, whereas adenoviruses were as frequent as enteroviruses in myocarditis. Persistence of viral infection was associated with disease deterioration. Viral myocarditis relapsed after transplantation.
authors.affiliation: Department of pathology, University of Padua Medical School, Padua, Italy. cardpath@unipd.it
authors.forename: Fiorella
authors.initials: F
authors.lastname: Calabrese
authors.forename: Emanuela
authors.initials: E
authors.lastname: Rigo
authors.forename: Ornella
authors.initials: O
authors.lastname: Milanesi
authors.forename: Giovanni M
authors.initials: GM
authors.lastname: Boffa
authors.forename: Annalisa
authors.initials: A
authors.lastname: Angelini
authors.forename: Marialuisa
authors.initials: M
authors.lastname: Valente
authors.forename: Gaetano
authors.initials: G
authors.lastname: Thiene
mesh_terms: D000293:Adolescent; D002311:Cardiomyopathy, Dilated / Q000175:diagnosis* / Q000503:physiopathology / Q000821:virology*; D002648:Child; D002675:Child, Preschool; D004279:DNA, Viral / Q000032:analysis*; D004699:Endocardium / Q000473:pathology / Q000821:virology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D008297:Male; D009205:Myocarditis / Q000175:diagnosis* / Q000503:physiopathology / Q000821:virology*; D011379:Prognosis; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D004279:DNA, Viral