Fetal Parvovirus Syndrome

Foetal parvovirus syndrome is a foetopathy likely to occur when a pregnant woman is infected by parvovirus B19. In adults, the virus causes a butterfly erythema infectiosum (also called Fifth Disease; 'slapped cheek disease') and flu-like symptoms with symmetric polyarthralgias, which usually do not warrant prenatal diagnosis.

Etiology

The pathogenesis of foetal parvovirus infections lies in the virus affinity for progenitor erythroid cells, with infection resulting in aplastic crisis. Anaemia induces a risk of hydrops and foetal death by cardiac failure in 10 to 20% of cases.

Diagnostic methods

Diagnosis is established by evidence of either a severe aregenerative anaemia and virus cells (by electronic microscopy) in foetal blood, or viral DNA in amniotic fluid by PCR analysis.

Antenatal diagnosis

In most cases, prenatal diagnosis of parvovirus infection is performed on the basis of a foetal hydrops.

Management and treatment

Management of aplastic crisis using foetal transfusions is debated, but experience has prompted the use of intrauterine transfusion for severely affected foetuses at less than 32 weeks of gestation.

Prognosis

No significant sequelae were found in the long-term outcomes of one third of children exposed in utero to maternal parvovirus B19 infection.