Cervico-vaginal Chlamydia trachomatis infection in pregnant adolescent and adult women. A morphologic and immunofluorescent study

Molecular detection ofChlamydia trachomatis and HPV infections in cervical samples with normal and abnormal cytopathological findings

It has been suggested that Chlamydia trachomatis (CT) and human papillomaviruses (HPV) co-infection could contribute to development of intraepithelial lesions. In this study, HPV and CT-DNA were investigated in 250 cervicovaginal samples of patients from Minas Gerais, Brazil. The cytological analysis revealed that 70% of samples (175) were negative, 5.2% (13) presented atypical squamous or glandular cells of undetermined significance (ASCUS/AGUS), 12.4% (31) presented low-grade squamous intraepithelial lesion (LSIL), 10.8% (27) high-grade squamous intraepithelial lesion (HSIL), and 1.6% (4) invasive carcinoma. HPV-DNA and HPV/CT co-infection was observed in 40% (100/250) and in 5.2% (13/250) of samples, respectively. Among the positive cytological samples, HPV-DNA was detected in 73.3% and CT-DNA in 9.33% and in 13%, if only the HPV positive samples were considered. The highest co-infection rate (15.4%) was observed among ASCUS/AGUS samples. Although a significant association was found for HPV infection and the precursor lesions of cervical cancer, it was not possible to establish a significant association between these lesions and CT or HPV/CT co-infection.

Increased Frequency of Bacterial Vaginosis and Chlamydia trachomatis in Pregnant Women with Human Papillomavirus Infection

The aim of this study was to verify the presence of bacterial vaginosis (BV), Candida sp, Chlamydia trachomatis, Neisseria gonorrhoeae, to determine the prevalence of tobacco use and measure vaginal pH (VpH) in pregnant women with (n = 26) and without (n = 26) human papillomavirus (HPV) infection, and make comparisons between these 2 groups. HPV, C. trachomatis and N. gonorrhoeae were diagnosed using hybrid capture, BV using clinical criteria, and Candida sp via cultures. A digital pH meter was used to measure VpH. The frequencies of Candida sp were 19.2 and 23.1% (p = 1), and VpH was 4.4 +/- 0.4 and 4.3 +/- 0.4 (p = 0.23), in the HPV-positive and HPV-negative groups, respectively. Compared to the group of pregnant women without HPV infection, those with HPV infection had a significantly higher prevalence of tobacco use (50 vs. 11.5%; p = 0.006), BV (53.8 vs. 15.4%; p = 0.007), and C. trachomatis (34.6 vs. 7.7%; p = 0.039). No case of N. gonorrhoeae was diagnosed. All cases of C. trachomatis and BV had high-grade HPV infection.

Reliability of cytology to detect chlamydial infection in asymptomatic women

Chlamydia trachomatis is a frequent sexually transmitted disease. The diagnosis of C. trachomatis infection by cytology is controversial. We compared the ability of Papanicolaou (Pap) smears to detect C. trachomatis infection with antigen detection (enzyme immunoassay; EIA) and polymerase chain reaction (PCR). One hundred sixty-seven women attending a therapeutic abortion clinic were enrolled in the study. Endocervical samples were first collected for EIA and PCR, and then Pap smears were prepared for cytologic evaluation. Eight patients were excluded from the study due to the lack of an endocervical component. The criteria established by Gupta and associates (Diagn Cytopathol 1988;4:224-229; Acta Cytol 1979;23:315-320) were used in this study to assess the specificity and sensitivity of the Pap smear in recognizing C. trachomatis infection. After EIA testing, the remaining sample was subjected to phenol-chloroform extraction to purify the DNA and then tested by PCR. Positive PCR samples were subjected to repeat phenol-chloroform and retested to confirm the positive result. Using a confirmed PCR or a blocked EIA as the extended gold standard, the incidence of C. trachomatis infection was 9.4%. Fifteen of the 159 cases reviewed were positive by extended gold standard. Thirteen (86.7%) of those 15 cases were interpreted as negative by cytology (false-negatives), and two (13.3%) cases were positive. Of the remaining 144 cases, 14 cases (9.7%) were interpreted as positive by cytology (false-positives) but were not confirmed by the extended gold standard. Ten (66.7%) of the 15 cases confirmed by the extended gold standard were interpreted as negative by EIA (false-negatives), and five (33.3%) were positive. There were no false-positives by EIA. In this study, the sensitivity and the specificity for cytology were 13.3% and 90.3%, respectively. The positive predictive value was 12.5%, and the negative predictive value for cytology was 90.9%. The sensitivity and the specificity for EIA were 33.3% and 100%, respectively. The positive predictive value was 100%, and the negative predictive value for EIA was 93.5%. Both EIA and cytology are insensitive methods compared with PCR. Based on these data, cytology should not be used to diagnose C. trachomatis infection in an asymptomatic female population with a moderate risk of C. trachomatis infection.