Chlamydia trachomatis detected in human placenta

Presence of Chlamydia trachomatis DNA in the amniotic fluid in women with preterm prelabor rupture of membranes

OBJECTIVE

The primary aim of this study was to assess the rate and load of amniotic fluid Chlamydia trachomatis DNA and their associations with intra-amniotic infection and intra-uterine inflammatory complications in women with preterm prelabor rupture of membranes (PPROM). The secondary aim was to assess the short-term morbidity of newborns from PPROM pregnancies complicated by amniotic fluid C. trachomatis DNA.

METHODS

A retrospective study of 788 women with singleton pregnancies complicated by PPROM between 24 + 0 and 36 + 6 weeks of gestation was performed. Transabdominal amniocenteses were performed at the time of admission. C. trachomatis DNA in the amniotic fluid was assessed by real-time polymerase chain reaction using a commercial AmpliSens® C. trachomatis/Ureaplasma/Mycoplasma hominis-FRT kit, and the level of Ct DNA was quantified.

RESULTS

Amniotic fluid C. trachomatis DNA complicated 2% (16/788) of the PPROM pregnancies and was present in very low loads (median 57 copies DNA/mL). In addition to amniotic fluid C. trachomatis DNA, other bacteria were detected in 62% (10/16) of the C. trachomatis DNA-complicated PPROM pregnancies. Amniotic fluid C. trachomatis DNA was associated with intra-amniotic infection, histologic chorioamnionitis (HCA), and funisitis in 31%, 47%, and 33%, respectively. The presence of C. trachomatis DNA accompanied by Ureaplasma species in the amniotic fluid was associated with a higher rate of HCA than the presence of amniotic fluid C. trachomatis DNA alone. The composite neonatal morbidity in newborns from PPROM pregnancies with amniotic fluid C. trachomatis DNA was 31%.

CONCLUSION

The presence of C. trachomatis DNA in the amniotic fluid is a relatively rare condition in PPROM. Amniotic fluid C. trachomatis DNA in PPROM is not related to intensive intra-amniotic and intr-auterine inflammatory responses or adverse short-term neonatal outcomes.

Trophoblast damage with acute and chronic intervillositis: disruption of the placental barrier by severe acute respiratory syndrome coronavirus 2

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was demonstrated in the placenta; however, the data on the prevalence of placental infection and associated histopathology are limited. To identify the frequency and features of SARS-CoV-2 involvement, we performed a clinicopathologic analysis of 75 placental cases from women infected at the time of delivery and 75 uninfected controls. Placental samples were studied with anti-SARS-CoV-2 immunohistochemistry and/or in situ hybridization. Positive results were confirmed by electron microscopy and quantitative reverse-transcription polymerase chain reaction (qRT-PCR). During delivery, only one woman had symptoms of coronavirus disease 2019, six women reported previous symptoms, and 68 women were asymptomatic. All neonates tested negative for SARS-CoV-2 as per nasopharyngeal swab PCR results. Obstetric histories were unremarkable in 29 of 75 SARS-CoV-2-positive and 8 of 75 SARS-CoV-2-negative women. Placental examination was normal in 12 of 75 infected and 3 of 75 uninfected subjects, respectively. In the remaining cases, placental pathology correlated with obstetric comorbidities without significant differences between SARS-CoV-2-positive and SARS-CoV-2-negative women. SARS-CoV-2 was identified in one placenta of an infected, but asymptomatic, parturient. Viral staining was predominantly localized to the syncytiotrophoblast (STB) which demonstrated marked damage accompanied by perivillous fibrin deposition and mixed intervillositis. A significant decrease of viral titers was detected in the attached umbilical cord compared with the villous parenchyma as per qRT-PCR. SARS-CoV-2 is seldom identified in placentas of infected women. Placental involvement by the virus is characterized by STB damage disrupting the placental barrier and can be seen in asymptomatic mothers without evidence of vertical transmission.

Lactobacillus crispatus inhibits the infectivity of Chlamydia trachomatis elementary bodies, in vitro study

Lactobacillus species dominate the vaginal microbiota of healthy reproductive-age women and protect the genitourinary tract from the attack of several infectious agents. Chlamydia trachomatis, a leading cause of sexually transmitted disease worldwide, can induce severe sequelae, i.e. pelvic inflammatory disease, infertility and ectopic pregnancy. In the present study we investigated the interference of Lactobacillus crispatus, L. gasseri and L. vaginalis, known to be dominant species in the vaginal microbiome, with the infection process of C. trachomatis. Lactobacilli exerted a strong inhibitory effect on Chlamydia infectivity mainly through the action of secreted metabolites in a concentration/pH dependent mode. Short contact times were the most effective in the inhibition, suggesting a protective role of lactobacilli in the early steps of Chlamydia infection. The best anti-Chlamydia profile was shown by L. crispatus species. In order to delineate metabolic profiles related to anti-Chlamydia activity, Lactobacillus supernatants were analysed by ¹H-NMR. Production of lactate and acidification of the vaginal environment seemed to be crucial for the activity, in addition to the consumption of the carbonate source represented by glucose. The main conclusion of this study is that high concentrations of L. crispatus inhibit infectivity of C. trachomatis in vitro.

Chlamydia trachomatis and placental inflammation in early preterm delivery

Chlamydiatrachomatis may infect the placenta and subsequently lead to preterm delivery. Our aim was to evaluate the relationship between the presence of Chlamydiatrachomatis and signs of placental inflammation in women who delivered at 32 weeks gestation or less. Setting: placental histology and clinical data were prospectively obtained from 304 women and newborns at the Erasmus MC-Sophia, Rotterdam, the Netherlands. C.trachomatis testing of placentas was done retrospectively using PCR. C.trachomatis was detected in 76 (25%) placentas. Histological evidence of placental inflammation was present in 123 (40%) placentas: in 41/76 (54%) placentas with C.trachomatis versus 82/228 (36%) placentas without C.trachomatis infection (OR 2.1, 95% CI 1.2–3.5). C.trachomatis infection correlated with the progression (P = 0.009) and intensity (P = 0.007) of materno-fetal placental inflammation. C.trachomatis DNA was frequently detected in the placenta of women with early preterm delivery, and was associated with histopathological signs of placental inflammation.

Emerging role of Chlamydia and Chlamydia-like organisms in adverse pregnancy outcomes

PURPOSE OF THE REVIEW

This review considers the roles of Chlamydia spp. and newly identified Chlamydia-like organisms in miscarriage, stillbirths and preterm labour in both animals and humans.

RECENT FINDINGS

The cause of miscarriage, stillbirth and preterm labour often remains unexplained. Intracellular bacteria that grow either poorly or not at all on media used routinely to detect human pathogens could be the aetiological agents of these obstetrical conditions. There is growing evidence that Chlamydia trachomatis, Chlamydophila abortus, Chlamydophila psittaci and Chlamydophila pneumoniae infections may result in adverse pregnancy outcomes in humans and/or animals. Waddlia, a Chlamydia-like organism first isolated from an aborted bovine, has emerged as an agent of abortion in cattle. Recently, Waddlia was also implicated in human foetal death. Moreover, Parachlamydia acanthamoebae is also abortigenic in ruminants. Whether additional novel Chlamydia-like organisms, such as Protochlamydia amoebophila, Neochlamydia hartmanellae, Criblamydia sequanensis, Rhabdochlamydia crassificans and Simkania negevensis, are involved in foetal loss or premature delivery remains to be determined.

SUMMARY

This review provides an update on the consequences of chlamydial infection during pregnancy and summarizes current evidence suggesting that some Chlamydia-related organisms are probably emerging obstetrical pathogens.

Chlamydia trachomatis infections in neonates and young children

In 1911, Lindner and colleagues identified intracytoplasmic inclusions in infants with a nongonococcal form of ophthalmia neonatorum called inclusion conjunctivitis of the newborn (ICN). Mothers of affected infants were found to have inclusions in their cervical epithelial cells, fathers of such infants had inclusions in their urethral cells, and the epidemiology of sexually transmitted chlamydial infections was revealed. Fifty years later, chlamydial isolation procedures were developed, and studies again demonstrated Chlamydia trachomatis as an etiology of ICN and the female birth canal as the reservoir. In the late 1970s, a report by Beem and Saxon described respiratory tract colonization and a distinct pneumonia syndrome in infected infants. Genital chlamydial infection is recognized as the world's most common sexually transmitted disease, with estimates of greater than 4 million new infections occurring annually in the United States. Although most C. trachomatis infections in men and women are asymptomatic, infection can lead to severe reproductive complications in women. The high prevalence in women of child-bearing age results in exposure of an estimated 100,000 neonates in the United States annually. Many of these infants develop conjunctivitis, pneumonia, or both in the first few months of life. Clinical features, diagnosis, treatment, and approaches to prevention of conjunctivitis and pneumonia in the newborn and young infant are reviewed here. Appropriate testing for chlamydial infection in a pediatric victim of sexual assault and the implications of identifying C. trachomatis in suspected cases of childhood sexual abuse also are reviewed.

Bacterial etiology for chronic villitis is not supported by polymerase chain reaction for 16S rRNA DNA

Chronic villitis is characterized by chorionic villi infiltrated by lymphocytes, histiocytes, and sometimes plasma cells. In a small percentage of cases, an infectious agent can be demonstrated within areas of chronic villitis. However, the pathogenesis of most lesions is idiopathic. Chronic villitis may represent the direct spread of chronic endometrial infection by bacterial organisms that are particularly problematic for culture. To test this hypothesis, polymerase chain reaction (PCR) using primers for the universal bacterial 16S rRNA DNA was performed on DNA extracted from areas of chronic villitis selected from placentas in the Yale Pathology database. Specific areas of chronic villitis were first confirmed by examination of sections stained with hematoxylin and eosin and then removed from archived paraffin blocks. Control tissue spiked with known bacterial counts was also prepared to test the sensitivity of the experiment. All tissue was deparaffinized, dehydrated, and digested with proteinase K. DNA extraction was performed with the Gentra Puregene kit. PCR was done using primers p11 and p13 for the 16S rRNA DNA. The 233-bp amplified target product was identified by agarose gel electrophoresis. Nineteen specimens with multifocal chronic villitis without confinement to anchoring villi were studied. None of the chronic villitis specimens had a demonstrable product using the PCR primers for 16S rRNA DNA, despite adequate DNA in the samples and controls. The assay was sensitive down to approximately 1500 bacteria per specimen. In conclusion, these data do not support a bacterial etiology for chronic villitis.

Serum C-reactive protein and Chlamydia trachomatis antibodies in preterm delivery

OBJECTIVE

To assess the association between Chlamydia trachomatis antibodies, antibodies to C trachomatis heat shock proteins 60 and 10, and C-reactive protein (CRP) levels in maternal serum measured by highly sensitive CRP assay during the first trimester and spontaneous preterm delivery before 37 weeks of gestation.

METHODS

This was a nested case-control study of 104 spontaneous preterm singleton deliveries (cases) and 402 term singleton deliveries, as controls, of mothers belonging to the population-based Northern Finland 1966 Birth Cohort. Data on 2,309 first deliveries were available from the Finnish Medical Birth Register. Serum C trachomatis and C pneumoniae antibodies were measured by the microimmunofluorescence test and chlamydial heat shock proteins 60 and 10 antibodies by enzyme immunoassay using recombinant proteins as antigens, and highly sensitive CRP levels were quantified with highly sensitive immunoenzymometric assay.

RESULTS

Highly sensitive CRP levels were higher and C trachomatis immunoglobulin G levels (pools and individual serotypes) were more often present (thought not nominally significantly in all cases) in the women with preterm compared with term deliveries. Elevated immunoglobulin G levels of C trachomatis antibodies or elevated highly sensitive CRP levels alone, however, did not increase the estimated risk for preterm delivery, but when they were present simultaneously, the estimated risk for preterm delivery was 4-fold (odds ratio 4.3, 95% confidence interval 2.0-9.3). Among the women delivered at or before 34 weeks of gestation, the estimated risk was even more evident (odds ratio 5.6, 95% confidence interval 2.1-14.5). The preterm delivery rate was 26.5% for those with C trachomatis antibodies and 18.8% for those without C trachomatis antibodies.

CONCLUSION

The results of the present study suggest that chlamydial infection in the first trimester is associated with preterm delivery.

LEVEL OF EVIDENCE

II-2.

Sustained high prevalence of Chlamydia trachomatis infections in female army recruits

BACKGROUND

Chlamydia trachomatis infections are prevalent among young sexually active females, have serious sequelae, and are mostly asymptomatic. Screening and treatment of infected females has been demonstrated to prevent sequelae such as pelvic inflammatory disease.

GOAL

To assess prevalence and risk factors for chlamydia infection in US Army female recruits, whether these changed over time, and to examine variables contributing to any observed patterns.

STUDY DESIGN

Prevalence study of 23,010 non-healthcare-seeking female Army recruits enrolled in a chlamydia screening program at Fort Jackson, SC, from January 1996 through June 1999. Each of the 4-year cohorts was examined separately for prevalence and risk factors.

MAIN OUTCOME MEASURES

Urine-based testing for C trachomatis by ligase chain reaction was used to determine prevalence, and questionnaires were used to collect demographic and risk information. State home of record for each recruit was transformed into Public Health reporting region: West, Midwest, South, Northeast, and Territories.

RESULTS

Prevalence for all years was 9.51%, but a progressive increase from 8.51% to 9.92% occurred over the course of study (P=0.018). The proportion of individuals reporting specific risk factors during the 90 days preceding the study generally decreased over time. In a regression model, significant risk factors for infection included black race, age 25 years or younger, home-of-record from the South, being screened during years 3 and 4 of the study, more than one sex partner, a new sex partner, and history of any sexually transmitted disease. Condom use was protective. In another model controlling for age and home-of-record from the South, being screened in years 2, 3, and 4 of the study were significantly predictive for being chlamydia positive.

CONCLUSION

A high and slightly increasing prevalence of C trachomatis infection was observed among young females entering the military over 4 consecutive years. Young age, black race, home-of-record from the South, more than one sex partner, a new sex partner, condom use, and a history of having a sexually transmitted disease were correlates of chlamydia infection. Sustained high rates of C trachomatis infection in this population provide clear justification for a chlamydia control program for young women entering the Army consisting of screening at entry on the basis of age and possibly home-of-record together with continued periodic rescreening.

SUMMARY

A study of 23,010 female Army recruits demonstrated that a high prevalence of C trachomatis was sustained during 4 years of observation. Year of study, young age, and being from the South were significant predictors of infection.

A murine model for the study of Chlamydia trachomatis genital infections during pregnancy

Pregnant BALB/c mice were inoculated intravaginally on day 5 of gestation with the Chlamydia trachomatis mouse pneumonitis biovar. Animals that received 10(5), 10(6), or 10(7) inclusion-forming units (IFU) of C. trachomatis delivered prematurely on days 15 to 16 of gestation. A focal inflammatory infiltrate was observed in the wall of the uterus on the day 14 of gestation in animals inoculated with 10(5) IFU. In this group of mice, immunohistochemical analysis showed chlamydial inclusions in the endometrium and fetal membranes.

No association of Chlamydia with abortion

Case reports and serological work have raised the possibility that chlamydias can infect the placenta and thus harm the fetus. We investigated the involvement of Chlamydia in a series of 195 unselected cases of spontaneous abortion or miscarriage. Formalin-fixed placental tissues from all cases were examined immunohistochemically, for the presence of chlamydial lipopolysaccharide, as well as histopathologically. A serum sample was collected from 187 of the patients for detection of anti-chlamydial antibodies by microimmunofluorescence. All placental sections were negative for chlamydial antigen. Serological findings indicated that 8 patients had been in contact with C. trachomatis, 15 patients with C. pneumoniae, and none with C. psittaci. A few cases of perivillitis or intervillitis were detected, but none exhibited the intracytoplasmic inclusions typical of C. psittaci. Although these results are negative a search for Chlamydia in abortion materials should be encouraged.

Comparison of performances of two commercially available tests, a PCR assay and a ligase chain reaction test, in detection of urogenital Chlamydia trachomatis infection

The diagnostic performance of a PCR test (Roche Cobas Amplicor CT/NG Test) and that of a ligase chain reaction (LCR) test (Abbott LCx Chlamydia trachomatis assay) were compared by using endocervical and urethral swab specimen culture as a reference test. First-void urine (FVU) and endocervical and urethral swab specimens were collected from 1,015 unselected patients attending a sexually transmitted disease clinic and a clinic for adolescents in Helsinki, Finland. Chlamydia trachomatis was cultured from samples from the endocervix or urethra. PCR was performed with fresh and frozen urine and the culture transport medium. LCR was performed with fresh and frozen urine and LCx swab transport medium. Diagnostic consistency and diagnostic accuracy were statistically tested. The test results were identical for 984 patients (97%). Discrepant results were observed for 31 patients. Overall, LCR and PCR showed excellent kappa coefficients of consistency for both swab and FVU specimens (0.93 and 0.95, respectively). Sixty-one patients (6%) were culture positive. Testing of FVU by LCR or PCR increased the overall positivity rates to 7.0 and 7.7%, respectively. While PCR of FVU detected the greatest number of C. trachomatis infections (sensitivity, 96.1%), for some PCR-positive FVU specimens the results could not be confirmed (specificity, 99.6%). PCR and LCR were more sensitive than culture (sensitivities, 92 and 93% versus 79% for culture) in the diagnosis of genital C. trachomatis infection. In conclusion, both tests can be recommended for use in the clinical laboratory and for the screening of asymptomatic C. trachomatis infections.