Rationale of Longitudinal Cohort Study on Obstetrical Outcomes of Trichomonas vaginalis Infection in Kinshasa, DR Congo

Background: Trichomoniasis is the most common non-viral sexually transmitted infection (STI) in the world, and the occurrence of this infection during pregnancy is responsible for adverse obstetrical outcomes like premature labor, premature rupture of membranes (PROM) and low birth weight (birth weight < 2500 g). The association with a number of factors (maternal age, low level of education, low socio-economic status and multiple sexual partners, etc.) that can be found in our environment suggest its probably high prevalence amongst vaginal infections that are responsible for adverse obstetrical outcomes, but up-to-date estimates are lacking. Objective: To assess the obstetrical risk associated with Trichomonas vaginalis (T. vaginalis) infection in our environment. Methods: We designed a protocol for a prospective cohort study which will take place in four medical facilities in the city of Kinshasa, where all pregnant women with a pregnancy of at least 20 weeks and who will give written consent will be included. Vaginal swab specimens will be collected for T. vaginalis research by direct microscopy wet mount. Follow-up will consist of recording the process of the pregnancy and obstetrical outcomes. Conclusion: Results from this study will allow to enhance management and also bring updated estimates on T. vaginalis prevalence and its obstetrical outcomes for infected pregnant woman in our environment.

Drug resistance in the sexually transmitted protozoan Trichomonas vaginalis

Trichomoniasis is the most common, sexually transmitted infection. It is caused by the flagellated protozoan parasite Trichomonas vaginalis. Symptoms include vaginitis and infections have been associated with preterm delivery, low birth weight and increased infant mortality, as well as predisposing to HIV/AIDS and cervical cancer. Trichomoniasis has the highest prevalence and incidence of any sexually transmitted infection. The 5-nitroimidazole drugs, of which metronidazole is the most prescribed, are the only approved,effective drugs to treat trichomoniasis. Resistance against metronidazole is frequently reported and crossresistance among the family of 5-nitroimidazole drugs is common, leaving no alternative for treatment, with some cases remaining unresolved. The mechanism of metronidazole resistance in T. vaginalis from treatment failures is not well understood, unlike resistance which is developed in the laboratory under increasing metronidazole pressure. In the latter situation, hydrogenosomal function which is involved in activation of the prodrug, metronidazole, is down-regulated. Reversion to sensitivity is incomplete after removal of drug pressure in the highly resistant parasites while clinically resistant strains, so far analysed, maintain their resistance levels in the absence of drug pressure. Although anaerobic resistance has been regarded as a laboratory induced phenomenon, it clearly has been demonstrated in clinical isolates. Pursuit of both approaches will allow dissection of the underlying mechanisms. Many alternative drugs and treatments have been tested in vivo in cases of refractory trichomoniasis, as well as in vitro with some successes including the broad spectrum anti-parasitic drug nitazoxanide. Drug resistance incidence in T. vaginalis appears to be on the increase and improved surveillance of treatment failures is urged.

Trichomonas vaginalis and Chlamydia trachomatis Prevalence,Incidence and Associated Factors in Pregnant Adolescents from Belém City,in the Brazilian Amazon

Background: Adolescents are disproportionally affected by sexually transmitted infections (STI). Chlamydia trachomatis (CT) and Trichomonas vaginalis (TV) are the most frequent curable STI in adolescents, causing serious consequences for their reproductive health. Therefore, we aimed to determine the prevalence and incidence of CT and TV, as well as their risk factors in pregnant adolescents from Belém, northern Brazilian Amazon. Methods: This prospective study enrolled 199 adolescents up to 20 weeks of pregnancy. They were scheduled for follow-up visit between 28 and 29 weeks of pregnancy. Sociodemographic and behavioral data were obtained by interview. Cervicovaginal samples were taken to test for TV, CT, Neisseria gonorrhoeae and bacterial vaginosis. Univariate and multivariate analyses were performed to test the association of prevalent/incident CT and TV with the variables. Results: Prevalence of cervical CT infection was 33.7% (n = 67/ 199), and for trichomoniasis it was 4.0% (n = 8/199). Cervical ectopy increased the risk for prevalent CT (OR, 1.93;95% CI, 1.01 - 3.70), while having treated vaginal discharge in the past (OR, 0.51;95% CI, 0.26 - 0.98) and being married (OR, 0.10;95% CI, 0.01 - 0.83) were protective against current CT and TV, respectively. Among the 95 (47.7%) adolescents who completed follow-up, 15 cases of incident CT were identified. Incident CT was associated with having a formal or informal job (OR, 28.4;95% CI, 2.1 - 391.6) and bacterial vaginosis treatment at the baseline (OR, 0.08;95% CI, 0.01 - 0.69). Conclusion: Prevalence and incidence rates of TV and CT are high in this population devoid of STI routine screening. Treatment of bacterial vaginosis may benefit this population by reducing risk for CT acquisition.

Trichomonas vaginalis perturbs the junctional complex in epithelial cells

Trichomonas vaginalis,a protist parasite of the urogenital tract in humans,is the causative agent of trichomonosis,which in recent years have been associated with the cervical cancer development.In the present study we analyzed the modifications at the junctional complex level of Caco-2 cells after interaction with two isolates of T.vaginalis and the influence of the iron concentration present in the parasite’s culture medium on the interaction effects.Our results show that T.vaginalis adheres to the epithelial cell causing alterations in the junctional complex,such as:(a)a decrease in transepithelial electrical resistance;(b)alteration in the pattern of junctional complex proteins distribution as observed for E-cadherin,occludin and ZO-1;and(c)enlargement of the spaces between epithelial cells.These effects were dependent on(a)the degree of the parasite virulence isolate,(b)the iron concentration in the culture medium,and(c)the expression of adhesin proteins on the parasite surface.

Incidence of Trichomonas vaginalis among Internally Displaced Women in Ibaka, Akwa Ibom State, Nigeria

A total of 282 outpatient pregnant antenatal and non-pregnant women from internally displaced camps attending the Poly Health Clinic (PHC) and the Enwang Health Centre (EHC) were examined for Trichomonas vaginalis infection. Direct wet mount microscopy and Giemsa staining techniques were used on High Vaginal Swab (HVS) specimens collected on sterile swab sticks. A prevalence of 20 (57.1%) was recorded using both methods;12 (7.2%) in PHC and 08 (6.2%) in EHC Mbo local government area, Akwa Ibom State respectively. Differences among pregnant and non-pregnant women used were statistically significant (P < 0.05). Women in the age group 15 - 19 years had the highest prevalence of infection 03 (10.5%), closely followed by those of age group 20 - 24 years 6 (6.8%). A total number of 14 (6.7%) infections were recorded among married women followed by single women with 06 (10%). A higher prevalence rate of 01 (24%) was recorded among women who attended Quranic level of education and 04 (16.7%) with uneducated women, this may be due to small sample size within this group of women. 12 (6.5%) in women with primary school education and 03 (4.7%) in women with secondary school level of education. The need for improved personal hygiene in IDP camps and other effective intervention programmes among these vulnerable groups of women is advocated.

Detection of Trichomonas Vaginalis Infection in Male Non-gonococcal Urethritis Patients by InPouch TV Culture and Polymerase Chain Reaction

Objective: To study the prevalence of Trichomonas vaginalis (TV) infection in Chinese male patients with nongonococcalurethritis (NGU), to evaluate the sensitivity and specificity ofurine-based and urethral swab polymerase chain reaction(PCR) detection, to set up a method for non-invasive detectionof male TV infection. Method: One hundred and five male NGU patients wereselected from a Beijing STD clinic. Two urethral swabs wereobtained from each patient, one for the InPouch TV culturesystem and the other for PCR. In addition, one first void urinespecimen was collected for PCR detection. Culture wasconsidered the 'gold standard'. The sensitivity, specificity,positive predictive value (PPV) and negative predictive value(NPV) of the two PCR detections were compared to cultureresults. Results: The prevalence of urine-based PCR and urethralswab PCR detection was 3.81% (4/105) and 4.76% (5/105)respectively. Compared to culture, the sensitivity, specificity,PPV and NPV were 80%, 100%, 100% and 99% for urinbased PCR and 80%, 99%, 80% and 99% for urethral swab PCR. Conclusion: TV is one of the etiological agents in male NGU,with a 4.76% prevalence of infection in our study. The urine-based PCR detection has higher sensitivity and specificity andprovides a noninvasive method more feasible in practice.

Trichomonas vaginalis and human papillomavirus:Association with the microbiota and burden on the cervix

Trichomoniasis and HPV infection are common non-viral and viral sexually transmitted diseases worldwide.Emerging evidence shows that the female genital tract and its microbiota are greatly affected by these pathogens.However,the relationship between Trichomonas vaginalis,the vaginal microbiome,and High-risk(HR)-HPV infection is complex and multifaceted.Studies have proven that concurrent infections of HIV and HPV increase the risk of cervical cancer.With this basis,a question arises:How does the concurrent infection of trichomonas vaginalis and HPV affect genital tract health?Does this concurrent infection enhance or inhibit the development of cervical lesions?This review aims to bring light to these questions.This review also covers the association of trichomonas vaginalis and HPV with the microbiota of the genital tract.

The secretory products of Trichomonas vaginalis decrease fertilizing capacity of mice sperm in vitro

Trichomonas vaginalis infection is one of the most prevalent sexually transmitted infections in humans and is now recognized as an important cause of infertility in men. There is little information about the effect of extracellular polymeric substances （EPS） from T. vaginalis on sperm, but previous reports do not provide a conclusive description of the functional integrity of the sperm. To investigate the impact of EPS on the fertilizing capacity of sperm, we assessed sperm motility, acrosomal status, hypo-osmotic swelling, and in vitro fertilization rate after incubating the sperm with EPS in vitro using mice. The incubation of sperm with EPS significantly decreased sperm motility, viability, and functional integrity in a concentration and time-dependent manner. These effects on sperm quality also resulted in a decreased fertilization rate in vitro. This is the first report that demonstrates the direct negative impact of the EPS of T. vaginalis on the fertilization rate of sperm in vitro. However, further study should be performed using human sperm to determine if EPS has similar negative impact on human sperm fertilizing capacity in vitro.

OBSERVATION OF THE EFFECT OF S－（－）USNIC ACID SODIUM ON TRICHOMONAS VAGINALIS BY TRANSMISSION ELECTRON MICROSCOPE

This paper reports the ultrastructural changes of trichomonas vaginaiis (T. vag. ) under the action of s-(-)usnic acid sodium in vitro. These changes can be shown by the following results:At first, the degranulation of the rough endoplasmic reticulum (RER) took place, the polyribosomes disaggregated. And then, the Golgi complex and the endoplasmic reticulum dilated. The cytoplasmic matrix presented and inhomogeneous apperance. Finally, the biomembrane loosed and fractured.The cell nuclei presented the karyorrhexis.

A systematic identification of Kolobok superfamily transposons in Trichomonas vaginalis and sequence analysis on related transposases

Transposons are sequence elements widely distributed among genomes of all three kingdoms of life, providing genomic changes and playing significant roles in genome evolution. Trichomonas vaginalis is an excellent model system for transposon study since its genome （- 160 Mb） has been sequenced and is composed of - 65% transposons and other repetitive elements. In this study, we primarily report the identification of Kolobok-type transposons （termed tvBac） in T. vaginalis and the results of transposase sequence analysis. We categorized 24 novel subfamilies of the Kolobok element, including one autonomous subfamily and 23 non-autonomous subfamilies. We also identified a novel H2CH motif in tvBac transposases based on multiple sequence alignment. In addition, we supposed that tvBac and Mutator transposons may have evolved independently from a common ancestor according to our phylogenetic analysis. Our results provide basic information for the understanding of the function and evolution of tvBac transposons in particular and other related transposon families in general.

Molecular Detection of Pathogens Involved in Sexually Transmitted Infections in Brazzaville, Congo

The objective of this multicentric study was to assess the prevalence of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma génitalium and Trichomonas vaginalis infections in Brazzaville, in the Republic of Congo, using molecular methods. From January to December 2021, the sexually transmitted disease risk participants were recruited from six centers: The Association of Young HIV-Positive People of Congo, The Congolese Association for Family Welfare, The Association for Support to Vulnerable Groups, Talangaï hospital, Brazzaville university hospital (outpatient service) and the private clinic COGEMO (outpatient service). The real-time multiplex PCR was carried out to detect these pathogens. Each patient had at least one specimen (urine, urethral, anal and/or vaginal samples). The patients were considered infected when one of their samples was positive. 287 participants made of 227 women and 60 men were tested. The general prevalence of these infections was: Chlamydia trachomatis 2.79%, Neisseria gonorrhoeae 3.14%, Mycoplasma génitalium 3.45% and Trichomonas vaginalis 2.97. The prevalence rates according to sex were: C. trachomatis, M. génitalium, N. gonorrhea and T. vaginalis were 1.32%, 2.05%, 1.32% and 3.42% in women and 8.33%, 7.02%, 10% and 1.75% in men, respectively. Most infected patients were asymptomatic. Prevalence rates were higher in bisexual individuals, with the exception of T. vaginalis which showed higher prevalence in heterosexual patients. The bisexual and homosexual individuals represent a major public health problem in sexually active young adults, particularly among men having sex with men. These sexually transmitted infections are mainly asymptomatic, their diagnosis and management remain difficult in developing countries.

Ultrastructural and immunohistochemical studies on Trichomonas vagi nalis adhering to and phagocytizing genitourinary epithelial cells

Background Trichomonas vaginalis (T. vaginalis ) belongs to a common sexually transmitted disease pathogen causing genitourinary trichomoniasis in both sexes. We investigated the pathogenetic mechanism of gen itourinary trichomoniasis.Methods Cultured T. vaginalis bodies were injected into the vaginas of rats, or incubated with genitourinary epithelial cells of female subjects, male subjects, and sperm. The ultrastructural and microscopic changes were observed via transmission and scanning electron microscopy and through microscopic histochemistry.Results Groups of T.vaginalis adhered to PAS positive colum nar cells at the surface of stratified epithelium in the middle and upper portions of the vaginas. They a lso traversed under these cells. The parasites were shown to be PAS, cathepsin D, and actin positive, and they could release hydrolase into the cytoplasm of adher ed epithelial cells. In the amebiform T.vaginalis, microfilaments were arranged into reticular formation. Similar phenomena were found during the interaction of T.vaginalis with host cells, both in vitro and in vivo. Usually several protozoa adhered to a n epithelial cell and formed polymorphic pseudopodia or surface invaginations to surround and phagocytize the microvilli or other parts of the epithelial cytoplasm. Adhesion and phagocytosis of sperm by the protozoa occurred at 15-30 minutes of incubation. Digestion of sperm was found at 45-75 minutes and was complete at 90-105 minutes.Conclusions T.vaginalis tends to parasitize at the fornix o f the vagina, because this is the site where columnar cells are rich in mucinogen granules and thei r microvilli are helpful for adhesion and nibbling. T.vaginalis possesses some invad ing and attacking abilities. Shape change, canalization, encystation, phagocytosis, digestion, the cell coat, cytoskeleton, and lysosome all play important roles in the process of adhesion. They have two methods of phagocytosis: nibbling and ingestion. Genitourinary epithelium may be injured directly by the digestive action of hydrolases, phagocytosis, and the mechanical action of pseudopodia.

Identifcation of the Phosphorylated Residues in TveIF5A by Mass Spectrometry

The initiation factor elF5A in Trichomonas vaginalis （TvelF5A） is previously shown to undergo hypusination, phosphorylation and glycosylation. Three different pI isoforms of TvelF5A have been reported. The most acidic isoform （pI 5.2） corresponds to the precursor TvelF5A, whereas the mature TvelF5A appears to be the most basic isoform （pI 5.5）. In addition, the intermediary isoform （pI 5.3） is found only under polyamine-depleted conditions and restored with exogenous putrescine. We propose that differences in PI are due to phosphorylation of the TvelF5A isoforms. Here, we have identified phosphorylation sites using mass spectrometry. The mature TvelF5A contains four phosphorylated residues （$3, T55, T78 and T82）. Phosphorylation at $3 and T82 is also identified in the intermediary TvelF5A, while no phosphorylated residues are found in the precursor TvelF5A. It has been demonstrated that elF5A proteins from plants and yeast are phosphorylated by a casein kinase 2 （CK2）. Interestingly, a gene encoding a protein highly similar to CK2 （TvCK2） is found in T. vaginalis, which might be involved in the phosphorylation of TvelF5A in T. vaginalis.