Discordant prenatal diagnosis of congenital toxoplasmosis in a dizygotic pregnancy

Incidence of toxoplasmosis in 5532 pregnant women in Crete, Greece: management of 185 cases at risk

OBJECTIVES

To study the incidence of toxoplasmosis in pregnant women in Crete and to test a designed protocol for handling those at risk of delivering congenitally infected infants.

STUDY DESIGN

Pregnant women were screened serologically over a period of 5 years. Cases with suspected acute toxoplasmosis were treated, peripheral blood (PB), and amniotic fluid (AF) tested by polymerase chain reaction (PCR) and culture, and fetuses monitored by ultrasonography. The absence of congenital infection in infants was confirmed by serology and clinical evaluation.

RESULTS

Of the 5532 pregnant women followed, 70.57% remained seronegative, 29.45% were seropositive, and there was direct evidence of seroconversion in six cases. Acute toxoplasmosis was suspected in 185 cases, maternal parasitemia was detected in five cases and positive amniotic fluid in one case. Congenital infection was excluded in all infants followed, based on the absence of ultrasound findings in utero, lack of clinical symptoms at birth, negative Western blotting (WB) at birth and 3 months later, and descending serology for a year.

CONCLUSION

Overall, 29.45% of the pregnant women followed were seropositive, 3.3% with suspected acute toxoplasmosis, and in 0.02% cases there was evidence of maternofetal transmission. The protocol tested allowed differentiation between acute and latent toxoplasmosis, safe management of the cases at risk and assisted in avoidance of unwarranted pregnancy terminations.

Toxoplasmose maternelle anté-conceptionnelle et choriorétinite chez des jumelles

A maternal toxoplasmosis before conception is exceptionally transmitted to the fetus. We report an observation of twin sisters who presented congenital toxoplasmosis with chorioretinitis detected at nine months of age. The anamnesis revealed that the mother had had toxoplasmosis one month before conception. In the event of preconceptual infections, we propose fetal ultrasonography, histological examination of the placenta at delivery, as well as a pediatric follow-up of the infants (serological samples every month, cranial ultrasonography, fundus oculi).

Congenital toxoplasmosis in twins: a report of fourteen consecutive cases and a comparison with published data

BACKGROUND

The combined influence of congenital toxoplasmosis and twin pregnancy on the duration of gestation has not been previously examined. Similarly little is known about the influence of genetic factors on the clinical course of this disease. The present study addresses these issues.

PATIENTS AND METHODS

Fourteen consecutive twin pairs born of mothers with Toxoplasma seroconversion during pregnancy were monitored after birth and during childhood, and the relevant data were compared with those already documented for similar cases.

RESULTS

The presumed time of gestation at which women became infected was earlier in noninfected than in infected twins (P = 0.007). Congenital infection did not influence the duration of pregnancy either in our own cases [36.2 +/- 4.3 weeks for noninfected children and 37.4 +/- 1.8 weeks for infected ones (P = 0.45)] or in previously published ones [35.4 +/- 3.6 weeks (P = 0.69)]. The infection status was identical for monozygotic twins (with one exception) but different for dizygotic ones (19 of 20 vs.35 of 45 cases). The clinical course through childhood corresponded more closely for monozygotic twins than for dizygotic ones [17 of 20 vs.20 of 45 cases (P = 0.007)].

CONCLUSION

Twin pregnancy is not a risk factor either for premature birth or for Toxoplasma infection in contaminated twins. The closely corresponding infection status between monozygotic twins highlights the crucial role played by the placenta in disease transmission. However, the substantial proportion of discrepant clinical courses suggests that other, as yet unknown, factors may be involved.