title: Parvovirus infects cardiac myocytes in hydrops fetalis.
abstract: Parvovirus infection during pregnancy is an important cause of hydrops fetalis. It is attributed to anemia caused by viral-induced destruction of red blood cells. Infection of other organs has been reported including the heart, liver, and lungs. Few of these reports, however, convincingly demonstrate virions within the functional parenchyma of the tissue. This is of particular concern regarding myocardium in the context of hydrops fetalis which is, in part, due to cardiac failure. The problem in routine pathology practice is that most fetuses with the infection are macerated. This, in part, probably explains the paucity of published information on cardiac involvement. This study examined five cases of fatal hydrops fetalis with variable maceration with serologically proven parvovirus B19 infection. Transmission electron microscopy of cardiac tissue demonstrated intranuclear virions in both erythroid precursor cells and in cardiac myocytes in three of these cases. In each of these, immuno-gold electron microscopy provided confirmatory evidence of parvovirus infection. Virions were not identifiable where maceration had caused disintegration of nuclei in the myocytes. In addition, virions were absent in the three negative control cases where retroplacental hemorrhage was confirmed as the cause of death. This study suggests that parvovirus infection of cardiac myocytes may play a more important role in causing hydrops fetalis than previously realized. It also demonstrates that maceration should not discourage the use of electron microscopy.
authors.affiliation: Department of Pathology, Rotunda Hospital, Dublin 1, Ireland. aomalley@rotunda.ie
authors.forename: Aiveen
authors.initials: A
authors.lastname: O'Malley
authors.forename: Carole
authors.initials: C
authors.lastname: Barry-Kinsella
authors.forename: Caroline
authors.initials: C
authors.lastname: Hughes
authors.forename: Peter
authors.initials: P
authors.lastname: Kelehan
authors.forename: Deirdre
authors.initials: D
authors.lastname: Devaney
authors.forename: Eoghan
authors.initials: E
authors.lastname: Mooney
authors.forename: John
authors.initials: J
authors.lastname: Gillan
mesh_terms: D000293:Adolescent; D000328:Adult; D002213:Capsid / Q000648:ultrastructure; D005260:Female; D005313:Fetal Death; D019084:Fluorescent Antibody Technique, Indirect; D005865:Gestational Age; D006801:Humans; D015160:Hydrops Fetalis / Q000401:mortality / Q000473:pathology / Q000821:virology*; D008423:Maternal Age; D008854:Microscopy, Electron; D032383:Myocytes, Cardiac / Q000473:pathology / Q000821:virology*; D010322:Parvoviridae Infections / Q000401:mortality / Q000473:pathology / Q000821:virology*; D016732:Parvovirus B19, Human / Q000302:isolation & purification* / Q000472:pathogenicity / Q000648:ultrastructure; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000473:pathology / Q000821:virology*; D011256:Pregnancy Outcome; D018566:Pregnancy, High-Risk