Pathogenesis of pelvic inflammatory disease

IL-17C is a driver of damaging inflammation during Neisseria gonorrhoeae infection of human Fallopian tube

The human pathogen Neisseria gonorrhoeae ascends into the upper female reproductive tract to cause damaging inflammation within the Fallopian tubes and pelvic inflammatory disease (PID), increasing the risk of infertility and ectopic pregnancy. The loss of ciliated cells from the epithelium is thought to be both a consequence of inflammation and a cause of adverse sequelae. However, the links between infection, inflammation, and ciliated cell extrusion remain unresolved. With the use of ex vivo cultures of human Fallopian tube paired with RNA sequencing we defined the tissue response to gonococcal challenge, identifying cytokine, chemokine, cell adhesion, and apoptosis related transcripts not previously recognized as potentiators of gonococcal PID. Unexpectedly, IL-17C was one of the most highly induced genes. Yet, this cytokine has no previous association with gonococcal infection nor pelvic inflammatory disease and thus it was selected for further characterization. We show that human Fallopian tubes express the IL-17C receptor on the epithelial surface and that treatment with purified IL-17C induces pro-inflammatory cytokine secretion in addition to sloughing of the epithelium and generalized tissue damage. These results demonstrate a previously unrecognized but critical role of IL-17C in the damaging inflammation induced by gonococci in a human explant model of PID.

A Rare Case of Lymphocytic Ascites

Ascites can manifest as a result of many conditions, with cirrhosis being the most common cause in the United States. Here, we present a case of lymphocytic ascites, a less common variant that occurred due to infection with Chlamydia trachomatis. This was a 37-year-old female with a history of substance and sexual abuse who presented with the chief complaints of abdominal pain, abdominal distension, and weight gain. She was febrile on admission with a distended, tender abdomen. The more common cardiac, renal, and hepatic causes were ruled out with extensive workup. Diagnosis and therapeutic paracentesis were done with fluid analysis significant for lymphocyte predominance and absence of malignant cells. Multi-modal imaging had ruled out suspicious malignant masses but CT abdomen/pelvis did show complex large volume ascites. Urine chlamydia and gonorrhea polymerase chain reaction (PCR) had resulted positive for chlamydia, leading us to start Doxycycline. Other infectious workups were negative, but ascitic fluid chlamydia NAAT was positive. Though initially worsening, the patient started showing significant clinical improvement after starting doxycycline, with the resolution of ascites and associated symptoms. This case report intends to bring to attention the importance of testing for chlamydia infection in cases of lymphocytic ascites, especially in sexually active females.

A Report of Haemophilus influenzae Bacteremia With Acute Pelvic Inflammatory Disease

Sexually-transmitted organisms that frequently originate from the flora of the lower genital tract are often implicated in pelvic inflammatory disease (PID). Haemophilus influenzae, a pathogen found primarily in the upper respiratory tract, has been rarely associated with PID. Here we report a case of a young woman with PID whose blood cultures grew H. influenzae biotype II, a reminder that the endometrium can be the source of systemic H. influenzae infection when no typical primary focus is found.

Variable localization of Toll-like receptors in human fallopian tube epithelial cells

Objective

To determine the localization, expression, and function of Toll-like receptors (TLRs) in fallopian tube epithelial cells.

Methods

The localization of TLRs in fallopian tube epithelial cells was investigated by immunostaining. Surprisingly, the intensity of staining was not equal in the secretory and ciliated cells. After primary cell culture of fallopian tube epithelial cells, ring cloning was used to isolate colonies of ciliated epithelial cells, distinct from non-ciliated epithelial cells. The expression of TLRs 1–10 was examined by quantitative real-time polymerase chain reaction, and protein localization was confirmed by immunostaining. The function of the TLRs was determined by interleukin (IL)-6 and IL-8 production in response to TLR2, TLR3, TLR5, TLR7, and TLR9 ligands.

Results

Fallopian tube epithelial cells expressed TLRs 1–10 in a cell-type-specific manner. Exposing fallopian tube epithelial cells to TLR2, TLR3, TLR5, TLR7, and TLR9 agonists induced the secretion of proinflammatory cytokines such as IL-6 and IL-8.

Conclusion

Our findings suggest that TLR expression in the fallopian tubes is cell-type-specific. According to our results, ciliated cells may play more effective role than non-ciliated cells in the innate immune defense of the fallopian tubes, and in interactions with gametes and embryos.

Neisseria gonorrhoeae Challenge Increases Matrix Metalloproteinase-8 Expression in Fallopian Tube Explants

Background:Neisseria gonorrhoeae (Ngo) is the etiological agent of gonorrhea, a sexually transmitted infection that initially infects the female lower genital tract. In untreated women, the bacteria can ascend to the upper genital reproductive tract and infect the fallopian tube (FTs), which is associated with salpingitis and can lead to impaired FT function and infertility. The extracellular matrix (ECM) plays an important role in cell migration and differentiation in the female genital tract, and some pathogens modify the ECM to establish successful infections. The ECM is regulated by matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs), their endogenous inhibitors; MMP deregulation causes pathological conditions in a variety of tissues.

Results: The aim of this work was to analyze the expression and localization of MMP-3, MMP-8, MMP-9, and TIMP-1 in FT explants during Ngo infection using real-time PCR, immunohistochemistry, zymography and ELISA. No significant variations in MMP-3, MMP-9, and TIMP-1 transcript levels were observed. In contrast, a significant increase (p < 0.05) was observed for MMP-8 expression and was accompanied by stromal immunoreactivity in infected explants. ELISA results supported these findings and showed that MMP-8 release increased upon gonococcal infection.

Conclusions: Our results indicate that gonococcal infection induces increased MMP-8 expression, which might contribute to FT damage during infection.

The natural history of Chlamydia trachomatis infection in women: a multi-parameter evidence synthesis

BACKGROUND AND OBJECTIVES

The evidence base supporting the National Chlamydia Screening Programme, initiated in 2003, has been questioned repeatedly, with little consensus on modelling assumptions, parameter values or evidence sources to be used in cost-effectiveness analyses. The purpose of this project was to assemble all available evidence on the prevalence and incidence of Chlamydia trachomatis (CT) in the UK and its sequelae, pelvic inflammatory disease (PID), ectopic pregnancy (EP) and tubal factor infertility (TFI) to review the evidence base in its entirety, assess its consistency and, if possible, arrive at a coherent set of estimates consistent with all the evidence.

METHODS

Evidence was identified using 'high-yield' strategies. Bayesian Multi-Parameter Evidence Synthesis models were constructed for separate subparts of the clinical and population epidemiology of CT. Where possible, different types of data sources were statistically combined to derive coherent estimates. Where evidence was inconsistent, evidence sources were re-interpreted and new estimates derived on a post-hoc basis.

RESULTS

An internally coherent set of estimates was generated, consistent with a multifaceted evidence base, fertility surveys and routine UK statistics on PID and EP. Among the key findings were that the risk of PID (symptomatic or asymptomatic) following an untreated CT infection is 17.1% [95% credible interval (CrI) 6% to 29%] and the risk of salpingitis is 7.3% (95% CrI 2.2% to 14.0%). In women aged 16-24 years, screened at annual intervals, at best, 61% (95% CrI 55% to 67%) of CT-related PID and 22% (95% CrI 7% to 43%) of all PID could be directly prevented. For women aged 16-44 years, the proportions of PID, EP and TFI that are attributable to CT are estimated to be 20% (95% CrI 6% to 38%), 4.9% (95% CrI 1.2% to 12%) and 29% (95% CrI 9% to 56%), respectively. The prevalence of TFI in the UK in women at the end of their reproductive lives is 1.1%: this is consistent with all PID carrying a relatively high risk of reproductive damage, whether diagnosed or not. Every 1000 CT infections in women aged 16-44 years, on average, gives rise to approximately 171 episodes of PID and 73 of salpingitis, 2.0 EPs and 5.1 women with TFI at age 44 years.

CONCLUSIONS AND RESEARCH RECOMMENDATIONS

The study establishes a set of interpretations of the major studies and study designs, under which a coherent set of estimates can be generated. CT is a significant cause of PID and TFI. CT screening is of benefit to the individual, but detection and treatment of incident infection may be more beneficial. Women with lower abdominal pain need better advice on when to seek early medical attention to avoid risk of reproductive damage. The study provides new insights into the reproductive risks of PID and the role of CT. Further research is required on the proportions of PID, EP and TFI attributable to CT to confirm predictions made in this report, and to improve the precision of key estimates. The cost-effectiveness of screening should be re-evaluated using the findings of this report.

FUNDING

The Medical Research Council grant G0801947.

Natural products for the treatment of trachoma and Chlamydia trachomatis

The neglected tropical disease (NTD) trachoma is currently the leading cause of eye disease in the world, and the pathogenic bacteria causing this condition, Chlamydia trachomatis, is also the most common sexually transmitted pathogenic bacterium. Although the serovars of this bacterial species typically vary between ocular and genital infections there is a clear connection between genital C. trachomatis infections and the development of trachoma in infants, such that the solutions to these infections are closely related. It is the unique life cycle of the C. trachomatis bacteria which primarily leads to chronic infections and challenges in treatment using conventional antibiotics. This life cycle involves stages of infective elementary bodies (EBs) and reproductive reticulate bodies (RBs). Most antibiotics only target the reproductive RBs and this often leads to the need for prolonged therapy which facilitates the development of drug resistant pathogens. It is through combining several compounds to obtain multiple antimicrobial mechanisms that we are most likely to develop a reliable means to address all these issues. Traditional and ethnobotanical medicine provides valuable resources for the development of novel formulations and treatment regimes based on synergistic and multi-compound therapy. In this review we intend to summarize the existing literature on the application of natural compounds for controlling trachoma and inhibiting chlamydial bacteria and explore the potential for the development of new treatment modalities.

Chlamydia trachomatis and Mycoplasma genitalium plasma antibodies in relation to epithelial ovarian tumors

Objective. To assess associations of Chlamydia trachomatis and Mycoplasma genitalium antibodies with epithelial ovarian tumors. Methods. Plasma samples from 291 women, undergoing surgery due to suspected ovarian pathology, were analyzed with respect to C. trachomatis IgG and IgA, chlamydial Heat Shock Protein 60-1 (cHSP60-1) IgG and M. genitalium IgG antibodies. Women with borderline tumors (n = 12), ovarian carcinoma (n = 45), or other pelvic malignancies (n = 11) were matched to four healthy controls each. Results. Overall, there were no associations of antibodies with EOC. However, chlamydial HSP60-1 IgG antibodies were associated with type II ovarian cancer (P = .002) in women with plasma samples obtained >1 year prior to diagnosis (n = 7). M. genitalium IgG antibodies were associated with borderline ovarian tumors (P = .01). Conclusion. Chlamydial HSP60-1 IgG and M. genitalium IgG antibodies are in this study associated with epithelial ovarian tumors in some subsets, which support the hypothesis linking upper-genital tract infections and ovarian tumor development.

Infection of human fallopian tube epithelial cells with Neisseria gonorrhoeae protects cells from tumor necrosis factor alpha-induced apoptosis

Following infection with Neisseria gonorrhoeae, bacteria may ascend into the Fallopian tubes (FT) and induce salpingitis, a major cause of infertility. In the FT, interactions between mucosal epithelial cells and gonococci are pivotal events in the pathogen's infection cycle and the inflammatory response. In the current study, primary FT epithelial cells were infected in vitro with different multiplicities of infection (MOI) of Pil+ Opa+ gonococci. Bacteria showed a dose-dependent association with cells and induced the secretion of tumor necrosis factor alpha (TNF-alpha). A significant finding was that gonococcal infection (MOI = 1) induced apoptosis in approximately 30% of cells, whereas increasing numbers of bacteria (MOI = 10 to 100) did not induce apoptosis. Apoptosis was observed in only 11% of cells with associated bacteria, whereas >84% of cells with no adherent bacteria were apoptotic. TNF-alpha was a key contributor to apoptosis, since (i) culture supernatants from cells infected with gonococci (MOI = 1) induced apoptosis in naïve cultures, suggesting that a soluble factor was responsible; (ii) gonococcal infection-induced apoptosis was inhibited with anti-TNF-alpha antibodies; and (iii) the addition of exogenous TNF-alpha induced apoptosis, which was inhibited by the presence of increasing numbers of bacteria (MOI = 10 to 100). These data suggest that TNF-alpha-mediated apoptosis of FT epithelial cells is likely a primary host defense mechanism to prevent pathogen colonization. However, epithelial cell-associated gonococci have evolved a mechanism to protect the cells from undergoing TNF-alpha-mediated apoptosis, and this modulation of the host innate response may contribute to establishment of infection. Understanding the antiapoptotic mechanisms used by Neisseria gonorrhoeae will inform the pathogenesis of salpingitis and could suggest new intervention strategies for prevention and treatment of the disease.

Comparative model-based analysis of screening programs for Chlamydia trachomatis infections

The design of a screening program for asymptomatic genital infections with Chlamydia trachomatis, requires decisions about which sex or age group should be targeted and whether partner referral should be included in the program. To investigate the effects of various screening programs on the prevalence and incidence of asymptomatic C. trachomatis infections in women, in May 1996 to April 1997 in Bilthoven, the Netherlands, the authors used a stochastic simulation model for C. trachomatis transmission in an age-structured, heterosexual population with a sexually highly active core group. Different screening scenarios were implemented over a time period of 10 years. Prevalence, incidence, and the fraction of infected persons found by partner referral were computed. Through screening of men and women between ages 15 and 24 years (baseline scenario), the prevalence of asymptomatic infections in women could be reduced from 4.2% to 1.4% in 10 years. Increasing the age range of screening up to ages 29 or 34 years led to prevalences of 0.4% and 0.06%, respectively, after 10 years. About 28% of all infected persons were found via partner referral. There are considerable indirect positive effects of screening on those population groups that are not included in the screening because of the reduced risk of becoming infected. Partner referral contributes substantially to prevalence reduction.

How well is pelvic inflammatory disease managed in general practice? A postal questionnaire survey

OBJECTIVE

Many patients with pelvic inflammatory disease (PID) present to their general practitioners. Chlamydia trachomatis is the organism most commonly implicated in this condition. This study aims to examine how well PID is managed in the primary care setting and highlight areas for improvement.

METHODS

The study was performed by sending postal questionnaires to 180 randomly selected general practitioners in Birmingham. Given the example of a woman presenting clinically with PID, the doctors were asked questions on diagnosis and treatment. To assess factors that may influence the answers, they were also asked about their sex, year of qualification, and postgraduate training.

RESULTS

139 questionnaires (77%) were returned. 91.4% of the respondents feel confident in managing patients with PID, and only 9.3% would usually refer these patients on. However, 54.7% do not perform an endocervical swab for C trachomatis, 37.4% do not include anti-chlamydial antibiotics in their treatment regimen, and 24.5% do not advise sexual partners to be screened. Female doctors, those with higher degrees, or obstetrics and gynaecology experience were more likely to give anti-chlamydial therapy, but no factors of the respondents significantly influenced contact tracing behaviour.

CONCLUSIONS

The management of a patient presenting with PID should include investigation for C trachomatis and treatment with an appropriate antibiotic. As PID is often a sexually transmitted disease, contact tracing of sexual partners should be undertaken. The study suggests that a significant proportion of general practitioners would not have offered optimal management to patients with PID.

Azithromycin. A pharmacoeconomic review of its use as a single-dose regimen in the treatment of uncomplicated urogenital Chlamydia trachomatis infections in women

In women, Chlamydia trachomatis infection often occurs in the urethra or cervix, with up to 70% of infections associated with few or no symptoms. Inadequate treatment may lead to infection of the upper genital tract and subsequent pelvic inflammatory disease (PID) in 10 to 40% of patients. PID causes an increased relative risk of ectopic pregnancy of 2.5 to 7.9 and PID may also lead to tubal infertility in about 17% of patients. 60% of infants born of mothers with C. trachomatis infection may become infected, leading to conjunctivitis in 23% and pneumonia in 21%. All of these sequelae of C. trachomatis infection may require in- or outpatient treatment. With > 4 million infections estimated to occur each year in the US, C. trachomatis is one of the most common and costly of the sexually transmitted pathogens. Treatment options for uncomplicated C. trachomatis infections in nonpregnant women include single-dose azithromycin 1000 mg or doxycycline 100 mg twice daily for 7 days orally. In clinical trials, the bacteriological cure rate of single dose azithromycin 1000 mg (95 to 100%) was similar to that of oral doxycycline 200 mg/day for 7 days (88 to 100%) in nonpregnant women. Azithromycin was at least as well tolerated as doxycycline and was associated with mainly mild gastrointestinal adverse effects including diarrhoea, nausea and abdominal pain. Pharmacoeconomic analyses have sought to determine if the 2.7- to 12-fold higher acquisition costs of azithromycin in comparison with doxycycline are offset by its simple single-dose regimen which is likely to aid patient compliance and so optimise drug efficacy. All analyses were retrospective cost-effectiveness decision-tree models and mainly considered direct costs. All models incorporated an estimate of noncompliance with doxycycline and its influence on efficacy. For the treatment of confirmed C. trachomatis infection, azithromycin saved around $US1200 per major outcome avoided (1993 values; third-party payer perspective in the US) or US$3502 per case of PID avoided (1993 values; US healthcare system perspective) compared with doxycycline. If infection was treated empirically, azithromycin was more costly than doxycycline by $US792 (1993 values), but the result was sensitive to changes of some parameters of the model. Azithromycin was more costly than doxycycline from the perspective of a public health clinic which paid for the treatment of initial infection and acute sequelae only. Thus, pharmacoeconomic data from the US support the use of azithromycin in the treatment of nonpregnant women with confirmed C. trachomatis urogenital infections from the perspective of the healthcare system or third-party payer; however, from the perspective of a public clinic, doxycycline is the less costly option. Decreases in doxycycline compliance or azithromycin acquisition cost are factors that favour azithromycin.

Chlamydia trachomatis and ectopic pregnancy: retrospective analysis of salpingectomy specimens, endometrial biopsies, and cervical smears

AIMS

To examine the role of Chlamydia trachomatis in ectopic pregnancy by detection of DNA in archival salpingectomy specimens, and in their preceding cervical specimens and endometrial biopsies, by using the polymerase chain reaction (PCR).

METHODS

Archival paraffin embedded salpingectomy tissues (n = 48) from 37 women with ectopic pregnancy were examined for the presence of C trachomatis plasmid and omp1 DNA by PCR. In addition, preceding cervical specimens (n = 58) stored either as cervical cell suspensions or as archival cervical smears, and preceding endometrial biopsies (n = 18), taken 0-5.8 years before the ectopic pregnancy, were examined by PCR for the presence of C trachomatis.

RESULTS

C trachomatis DNA was detected in only one of the 48 salpingectomy specimens from 37 women. However, in six of the 37 women, C trachomatis DNA was detected in the genital specimens (cervix and/or endometrial) taken before salpingectomy. C trachomatis infections were mostly found in endometrial or cervical specimens taken more than three years before ectopic pregnancy. No chlamydial DNA was found in endometrial or cervical specimens taken at the same time of the ectopic pregnancy.

CONCLUSIONS

Although no C trachomatis DNA was found in salpingectomy specimens, several women with ectopic pregnancy had C trachomatis infections in endometrial and cervical specimens in the past. This suggests that at least in these cases the ectopic pregnancy is a late post-inflammatory complication of an ascending C trachomatis infection resulting in a scarred fallopian tube.