We studied the presence of C. trachomatis-specific IgG and IgM in adul
ts and newborns, respectively, and attempted isolation of the bacteria
in cell culture. The determination of antibodies was carried out by a
n IFA on C. trachomatis infected (L(2)434/Bu serotype) McCoy cells, cu
ltured in 24-well plastic plates. We found C. trachomatis-specific IgG
in 27% of women with clinical symptoms, in 40% of women being attende
d for periodic gynecological control, in 60% of infertile women and in
10% of pregnant women. A proportion comparison test revealed the pres
ence of specific IgG as highly significative for the group of infertil
e women as compared to the group of pregnant women (p < 0.0001). We di
vided the patients into four groups, in relation to the results of the
tests for specific IgG and C. trachomatis isolation. Seven out of 10
had positive isolation and negative IFA, 5 out of 8 had positive isola
tion and negative IFA. Twenty five out of 28 pregnant women had negati
ve isolation and positive IFA, finally, 63 out of 76 had both tests ne
gative. Statistical analysis using the McNemar proportion-comparison t
est suggests that IgG's presence is highly significant in pregnant wom
en with respect to other groups (p < 0.001). Our results suggest that
the demonstration of IgG is not enough for diagnostic purposes, except
in infertile women with a previous history of infection with C. trach
omatis. We isolated C. trachomatis in 20% of the newborns tested and 1
0% were also positive for IgM IFA. The diagnosis was improved by combi
ning both techniques. These results show the importance of the detecti
on of C. trachomatis in youngsters to avoid infertility and in pregnan
t women to prevent newborn infections and the possibility of premature
births and low weight babies.