FETAL MANIFESTATIONS OF PARVOVIRUS B19 INFECTION

• Nonimmune fetal hydrops.
• Usually occurs 4-6 weeks after maternal exposure.
• Has been reported as early as 1 week and as late as 12 weeks after exposure (1,2).
• Proposed mechanisms for the development of fetal hydrops include:
• Fetal anemia. The virus infects erythroid precursor cells resulting in erythroid hypoplasia, shortened red cell survival and hemolysis (3). Fetal anemia as low as 1.7 g/l has been reported (4).
• Cardiac failure secondary to a viral myocarditis. Parvovirus has been reported in cardiac muscle of infected fetuses (5). The anemia results in tissue hypoxia when results in a compensatory compensatory increase in cardiac output and hydrops (6).
• Spontaneous resolution of the hydrops, although rare has been reported (7).
• Rate of fetal loss and hydrops fetalis.
• General information on fetal hydrops.

REFERENCES

1. Public Health Laboratory Service Working Party on Fifth Disease: Prospective study of human parvovirus (B19) infection in pregnancy. Br Med J 1990;300:1166-1170.
2. Bond PR, Caul EO, Usher J et.al. Intrauterine infection with human parvovirus. Lancet 1986;1:448-449.
3. Burron PA, Caul EO. Fetal cell trophism of human parvovirus B19. Lancet 1988;1:767 (letter).
4. Anderson MJ, Khousam MN, Fleming KA. Human parvovirus B19 and hydrops fetalis. Lancet 1988;1:535.
5. Porter HJ, Quantrill AM, Fleming KA. B19 parvovirus infection of myocardial cells (letter). Lancet 1988;1:535-536.
6. Pryde PG, Nugent CE, Pridjian et.al. Spontaneous resolution of nonimmune hydrops fetalis secondary to human parvovirus B19 infection. Obstet Gynecol 1992;79:859-861.
7. Bhal PS, Davies NJ, Westmoreland D et.al. Spontaneous resolution of non-immune hydrops fetalis secondary to transplacental parvovirus B19 infection. Ultrasound Obstet Gynecol 1996;7:55-57.