BackgrounchMaternal seroconversion for Toxoplasma gondii during

pregnancy is said to have good role for diagnosis of congenital infection.

Objective: to determine whether maternal serum levels of antibodies

against Toxoplasma gondii parasite are associated with definite fetal

parasitic infectation and consequent pathology or not.

Patients and Methods: Maternal serum IgA levels against Toxoplasma

gondii were measured in 29 patients with strongly suggested congenital

toxoplasmosis (maternal IgM seroconversion with fetal pathology) out of

200 patients with suggestive fetal pathology. Their pregnancies were

affected by hydrocephalus (Group 1, n=17), other congenital anomalies

and hydropes fetalis (Group II, n=6), and fetal loss (Group III, n=6). They

were compared with 17 women with negative IgM and normal pregnancies

as a control group (Group IV). All cases were examined by

ultrasonography for obtaining amniotic fluid samples during pregnancy.

After termination and if possible fetal serum samples were drawn for

measuring the same antibodies. Also, placental imprints, placental samples

and umbilical cord samples were prepared for histopathological

examination for detection of parasite cysts in tissues.

Results: Cases presented by maternal IgM seroconversion against

Toxoplasma gondii during pregnancy with suggestive fetal pathology

(hydrocephalus, other anomalies, and abortions) showdd significantly

higher maternal specific Toxoplasma IgA levels than the control group

(166.7±27.2, 165.7±2I.l, and 149.7±9.1 respectively vs. 127.2±15.3,

p>0.001). Microscopic parasitic detection was positive in 2/11 (18.25) in the

amniotic fluid and in 1/11 (9.1%) in placental tissues of these cases.

Conventional serological neonatal testing for specific Toxoplasma IgA

revealed sensitivity and specificity of 77.8% and 100% respectively. The

combination of the results of conventional serological neonatal testing for

specific Toxoplasma IgA with the results of parasitic detection (amniotic

fluid and placental) resulted in sensitivity and specificity of 94.4 and 100

respectively.

Conclusions: Detection of specific Toxoplasma gondii IgA antibody
response by ELISA is more reliable than IgM level for diagnosis of
congenital toxoplasmoisis.