title: Fetal parvovirus B19 infection in a twin pregnancy with 1 twin presenting with hydrops fetalis and the other asymptomatic: a case report.
abstract: BACKGROUND
  Parvovirus B19 infection during pregnancy is a known cause of nonimmune hydrops, while about one third of maternal infection is asymptomatic. Spontaneous abortion, hydrops fetalis, intrauterine growth retardation and meconium peritonitis are possible manifestations of fetal infection, but the infection can also be asymptomatic.
  
  
  METHODS
  Both fetuses in a dichorionic, diamniotic twin pregnancy were infected with parvovirus B19 infection, but only 1 fetus presented with hydrops fetalis. That fetus died, while the other remained asymptomatic throughout the pregnancy. The mother had a normal delivery at 39 weeks of gestation, and the neonatal outcome of the surviving twin was normal apart from early-onset neonatal jaundice due to ABO incompatibility.
  
  
  CONCLUSIONS
  This case, together with others, illustrates that parvovirus B19 infection in twin fetuses can present differently despite the fact that the fetuses are nurtured in rather similar intrauterine environments. A severe complication in 1 twin does not preclude a normal outcome in the other. The possibility of different manifestations should be borne in mind so that parvovirus B19 infection remains high on the list of differential diagnoses of nonimmune hydrops affecting only 1 fetus in a twin pregnancy.
authors.affiliation: Department of Obstetrics and Gynaecology, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, N.T., Hong Kong. leungtn@yahoo.com.hk
authors.forename: Tse Ngong
authors.initials: TN
authors.lastname: Leung
authors.forename: Tak Yeung
authors.initials: TY
authors.lastname: Leung
authors.forename: Paul Kay Sheung
authors.initials: PK
authors.lastname: Chan
authors.forename: Tak Yuen
authors.initials: TY
authors.lastname: Fung
authors.forename: Tze Kin
authors.initials: TK
authors.lastname: Lau
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D005260:Female; D005313:Fetal Death; D006801:Humans; D015160:Hydrops Fetalis / Q000175:diagnosis*; D010322:Parvoviridae Infections / Q000150:complications / Q000175:diagnosis* / Q000196:embryology; D016732:Parvovirus B19, Human; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000175:diagnosis*; D011262:Pregnancy Trimester, Second; D011296:Prenatal Diagnosis; D014427:Twins