Epidemiology and treatment of trichomoniasis

Vaginal Tritrichomonas foetus infection in mice as an in vivo model for drug development against Trichomonas vaginalis

Trichomonas vaginalis is the causative agent of the common sexually transmitted disease, trichomoniasis, which affects more than a hundred million people worldwide. Metronidazole and tinidazole, agents belonging to the 5-nitroheterocyclic class of antimicrobials, are most often used to treat infection, but increased resistance has been reported and adverse effects of these drugs can be significant. Consequently, an urgent need exists for the development of novel drug entities against trichomoniasis. Critical for antimicrobial drug development is the demonstration of in vivo efficacy. Murine models of vaginal T. vaginalis infection are unreliable for unknown reasons. Meanwhile, murine infections with the related bovine pathogen, Tritrichomonas foetus, tend to be more robust, although susceptibility to different antimicrobials might differ from T. vaginalis. Here, we explored the utility of T. foetus infection as a surrogate model for drug development against T. vaginalis. Four different T. foetus strains caused robust vaginal infection in young mice, while none of four diverse T. vaginalis strains did. Comparison of drug susceptibility profiles revealed that T. foetus and T. vaginalis were similarly susceptible to a range of 5-nitroheterocyclic and gold(I) compounds. By comparison, proteasome inhibitors were 10- to 15-fold less active against T. foetus than T. vaginalis, although one of the proteasome inhibitors, bortezomib, had low micromolar activity or better against multiple strains of both trichomonads. Different strains of T. foetus were used to demonstrate the utility of the murine vaginal infection models for in vivo efficacy testing, including for bortezomib and a gold(I) compound. The differences in susceptibility to proteasome inhibitors may be partially explained by differences in the proteasome subunit sequences between the two trichomonads, although the functional relevance of the proteasome was similar in both organisms. These findings indicate that T. foetus can serve as a reliable surrogate model for T. vaginalis in vitro and in murine infections in vivo, but caution must be exercised for specific drug classes with targets, such as the proteasome, that may display genetic divergence between the trichomonads.

Trichomoniasis and retesting in Durham County, North Carolina, United States, 2021 - 2022

BACKGROUND

The Centers for Disease Control and Prevention recommends universal retesting within 3 months after treatment of Trichomonas vaginalis infection given high rates of persistent infection or reinfection, or if this is not possible, within 12 months following treatment. Data is lacking on how often this is actually done.

METHODS

We analyzed the demographic and clinical characteristics, rate of return for the recommended retesting, concordance between wet prep and nucleic acid amplification testing, and percent positivity for T. vaginalis on repeat vaginal specimens at a local public health department in Durham, North Carolina, United States.

RESULTS

Of 193 females treated for trichomoniasis between March 1, 2021 - May 31, 2022, 83% were Black or African American and 44% between the ages of 20 and 29 years. Of these individuals, 32% had retesting performed within 3 months and 50% within 365 days after treatment. Females between the ages of 20 and 29 years were more likely to return for retesting than those between the ages of 30 and 39 years. Of those who returned for retesting, 10% were positive on repeat testing.

CONCLUSION

In this study, 50% of females diagnosed with trichomoniasis completed retesting within 365 days. Improved scheduling of clients at the time of trichomoniasis treatment and improved identification in our electronic health record of individuals diagnosed with trichomoniasis within the prior year would likely improve retesting rates. Given the high prevalence of trichomoniasis, expanded screening of asymptomatic females in settings where this is feasible may be warranted.

Disparities in adherence to retesting guidelines in women with Trichomonas vaginalis infection

BACKGROUND

Trichomoniasis is the most prevalent nonviral sexually transmitted infection in the United States. Numerous studies have shown disproportionately higher prevalence rates in non-Hispanic Black women. Because of the high rates of reinfection, the Centers for Disease Control and Prevention recommends retesting women treated for trichomoniasis. Despite these national guidelines, there are few studies examining adherence to retesting recommendations for patients with trichomoniasis. Adherence to retesting guidelines has been shown in other infections to be an important determinant of racial disparities.

OBJECTIVE

This study aimed to describe Trichomonas vaginalis infection rates, evaluate adherence to retesting guidelines, and examine characteristics of women who were not retested according to the guidelines in an urban, diverse, hospital-based obstetrics and gynecology clinic population.

STUDY DESIGN

We conducted a retrospective cohort study of patients from a single hospital-based obstetrics and gynecology clinic who were tested for Trichomonas vaginalis between January 1, 2015 and December 31, 2019. Descriptive statistics were used to examine guideline-concordant testing for reinfection among patients with trichomoniasis. Multivariable logistic regression was used to identify characteristics associated with testing positive and with appropriate retesting. Subgroup analyses were performed for patients who were pregnant and tested positive for Trichomonas vaginalis.

RESULTS

Among the 8809 patients tested for Trichomonas vaginalis, 799 (9.1%) tested positive at least once during the study. Factors associated with trichomoniasis included identifying as non-Hispanic Black (adjusted odds ratio, 3.13; 95% confidence interval, 2.52-3.89), current or former tobacco smoking (adjusted odds ratio, 2.27; 95% confidence interval, 1.94-2.65), and single marital status (adjusted odds ratio, 1.96; 95% confidence interval, 1.51-2.56). Similar associated factors were found in the pregnant subgroup analysis. For women with trichomoniasis, guideline-concordant retesting rates were low across the entire population, with only 27% (214/799) of patients retested within the recommended time frame; 42% (82/194) of the pregnant subgroup underwent guideline-concordant retesting. Non-Hispanic Black women had significantly lower odds of undergoing guideline-recommended retesting than non-Hispanic White women (adjusted odds ratio, 0.54; 95% confidence interval, 0.31-0.92). Among patients tested according to guideline recommendations, we found a high rate of Trichomonas vaginalis positivity at retesting: 24% in the entire cohort (51/214) and 33% in the pregnant subgroup (27/82).

CONCLUSION

Trichomonas vaginalis infection was identified at a high frequency in a diverse, urban hospital-based obstetrics and gynecology clinic population. Opportunities exist to improve on equitable and guideline-concordant retesting of patients with trichomoniasis.

TRiCit: A High-Throughput Approach to Detect Trichomonas vaginalis from ITS1 Amplicon Sequencing

Trichomoniasis, caused by Trichomonas vaginalis (TV), is the most common non-viral sexually transmitted infection (STI) worldwide, affecting over 174 million people annually and is frequently associated with reproductive co-morbidities. However, its detection can be time-consuming, subjective, and expensive for large cohort studies. This case-control study, conducted at the Mount Sinai Adolescent Health Center in New York City, involved 36 women with prevalent TV infections and 36 controls. The objective was to examine Internal Transcribed Spacer region-1 (ITS1) amplicon-derived communities for the detection of prevalent TV infections with the same precision as clinical microscopy and the independent amplification of the TV-specific TVK3/7 gene. DNA was isolated from clinician-collected cervicovaginal samples and amplified using ITS1 primers in a research laboratory. Results were compared to microscopic wet-mount TV detection of concurrently collected cervicovaginal samples and confirmed against TV-specific TVK3/7 gene PCR. The area under the receiver operating characteristics curve (AUC) for diagnosing TV using ITS1 communities was 0.92. ITS1 amplicons displayed an intra-class correlation coefficient (ICC) of 0.96 (95% CI: 0.93-0.98) compared to TVK3/7 PCR fragment testing. TV cases showed an increased risk of bacterial vaginosis (BV) compared to the TV-negative controls (OR = 8.67, 95% CI: 2.24-48.54, p-value = 0.0011), with no significant differences regarding genital yeast or chlamydia infections. This study presents a bioinformatics approach to ITS1 amplicon next-generation sequencing that is capable of detecting prevalent TV infections. This approach enables high-throughput testing for TV in stored DNA from large-scale epidemiological studies.

Trichomonas vaginalis infection and risk of cervical neoplasia: A systematic review and meta-analysis

OBJECTIVES

The evidence in the literature regarding the relationship between Trichomonas vaginalis (TV) infection and cervical neoplasia is conflicting. The main aim of this study was to evaluate the magnitude of the risk of cervical neoplasia associated with TV infection.

METHODS

A meta-analysis of observational studies, which provided raw data on the association of TV infection with cervical neoplasia, was performed. For this aim, we searched scientific databases (PubMed/Medline, Scopus, the Web of Sciences, and Embase) from inception to March 15, 2023. A random-effects model was applied by Stata 17.0 to calculate the pooled and adjusted odds ratios (ORs) with 95% confidence intervals (CI), including subgroup, sensitivity, and cumulative analyses to explore sources of heterogeneity.

RESULTS

Of the 2584 records initially identified, 35 eligible studies contributed data for 67,856 women with cervical neoplasia, and 933,697 healthy controls from 14 countries were included. The pooled (2.15; 1.61-2.87; I2 = 87.7%) and adjusted (2.17; 1.82-2.60; I2 = 31.27%) ORs indicated a significant positive association between TV infection and the development of cervical neoplasia. There was no significant change in pooled and adjusted ORs by applying sensitivity and cumulative analyses, indicating the robustness of our findings. The pooled OR was significant in most sub-group analyses. There was no publication bias in the included studies.

CONCLUSION

Our findings indicated that women with a TV infection are at significantly greater risk of cervical neoplasia. Future research, particularly longitudinal and experimental studies, should be done to better understand the various aspects of this association.

TRICHOMONAS VAGINALIS INFECTION AMONG ASYMPTOMATIC UNDERGRADUATE STUDENTS IN A PRIVATE UNIVERSITY IN OGUN STATE, NIGERIA

Background

Trichomonas vaginalis is one of the common non- viral sexually transmitted infections that infect both men and women worldwide. It is largely asymptomatic and its association with the risk of HIV transmission has made it a compelling public health concern. Therefore, this study aims to determine the prevalence and the risk factors associated with T. vaginalis among asymptomatic undergraduate students at Babcock University, Ilisan-Remo, Ogun state, Nigeria.

Materials and Methods

This is a descriptive cross-sectional study involving 246 asymptomatic students of Babcock University between February 2019 to April 2020. Information on socio-demographic and associated risk factors was obtained by structured-questionnaire in an interview-based manner. First-void urine was collected from each participant for the detection of T. vaginalis using the traditional wet prep method and TV in-pouch. The data were analyzed by SPSS Version 23.

Results

The overall prevalence of T. vaginalis among the participants was 12.2% (30/246). The use of wet-preparation showed 8.5% (21/246) while the use of TV inpouch yielded 12. 2% (30/246) prevalence of positive results. The results of the wet prep in comparison to the in-pouch technique was statistically significant among the study population. (P < 0.001). Sexual intercourse, use of hormonal contraceptives and practice of internet-based sex seeking behaviour were factors that had increase likelihood of T. vaginalis infection on multivariate analysis.

Conclusion

The occurrence of T. vaginalis and, its associated risk factors among the asymptomatic population in this study is very high. We advocate for the screening of young people.

Detection of metronidazole resistance in Trichomonas vaginalis using uncultured vaginal swabs

Trichomonas vaginalis (T. vaginalis) is the most prevalent sexually transmitted infection (STI) globally. Metronidazole is the drug of choice for treating T. vaginalis infections although metronidazole-resistant T. vaginalis has been reported in clinical isolates. The purpose of this study was to determine the presence of mutations in nitroreductase genes associated with metronidazole resistance in vaginal swabs testing positive for T. vaginalis. This study included 385 human immunodeficiency virus (HIV)-positive pregnant women. Vaginal swabs were collected from consenting pregnant women and used for the detection of T. vaginalis using the TaqMan assay. From the vaginal swabs, nitroreductase genes ntr4 and ntr6 containing mutations associated with metronidazole resistance were amplified using a quantitative polymerase chain reaction (PCR) assay. To validate the PCR assay, T. vaginalis cultured isolates with known metronidazole resistance profiles were used as controls in the mutation detection assays. The prevalence of T. vaginalis in the study population was 12.2% (47/385). Mutations associated with resistance to metronidazole were detected in more than 40% of the samples tested, i.e. 21/47 (45%) and 24/47 (51%) for ntr4 and ntr6, respectively. A total of 19 samples (40%) carried mutations for both ntr4 and ntr6 genes associated with metronidazole resistance. The validation assays showed a positive correlation between phenotypic and genotypic resistance profiles. This study found a high prevalence of mutations associated with metronidazole resistance. This is concerning since metronidazole is currently used in the syndromic management of STIs in South Africa. Molecular-based assays for monitoring metronidazole resistance profiles using nitroreductase genes may serve as a feasible method for antimicrobial surveillance studies for T. vaginalis.

Validation of a New High-Throughput BD COR System Using the BD CTGCTV2 Assay

This study determined the precision and reproducibility of results for the BD CTGCTV2 (CTGCTV2) assay on the BD COR System (COR). The clinical performance of the CTGCTV2 assay conducted on COR was compared with its performance on the BD MAX System (MAX) for detecting Chlamydia trachomatis, Neisseria gonorrhoeae, or Trichomonas vaginalis. The multiday precision and multisite reproducibility studies were conducted using contrived panels of positive and negative urine and PreservCyt specimens. A total of 433 panel members, generated from remnant clinical specimens, were tested in the clinical comparison study. Each panel member was tested three times on MAX and three times on COR. The results in the same testing group were compared for agreement by target. The cycle threshold scores from MAX and COR were analyzed by paired t-test and Deming regression. The CTGCTV2 assay on COR showed high reproducibility in the multiday and multisite precision analysis. The point estimates of positive percent agreement and negative percent agreement in the clinical comparison study for all three targets were greater than 95%, with all corresponding lower bounds of two-sided 95% CIs greater than 90%. Cycle threshold score comparison showed no systematic difference between the two systems. The results of this study show equivalent performance of the CTGCTV2 assay on the MAX and COR systems.

Evaluation and Management of Vaginitis

Vaginitis is a common concern for women across the lifespan. Vaginal symptoms may impact quality of life, and clinicians are challenged in the evaluation and management of bacterial vaginosis, Candida vaginitis, trichomoniasis, desquamative inflammatory vaginitis, and genitourinary syndrome of menopause.

Trichomonas vaginalis infection in Ethiopia: A systematic review and meta-analysis

BACKGROUND

An estimated 30 million new cases of Trichomonas vaginalis are recorded annually in sub-Saharan Africa. In Ethiopia, there is no study that systematically compiled the burden of T. vaginalis. Therefore, this study aimed to estimate the pooled prevalence of T. vaginalis in Ethiopia.

METHODS

Electronic databases such as PubMed/Medline, EMBASE, Science Direct, Scopus, HINARI, Google Scholar, and Cochrane Library were systematically searched, and studies with high-quality Newcastle Ottawa Scale scores were included. Analyses were performed using STATA version 14 software, and heterogeneity of studies was assessed using the Cochrane's Q test statistics and I² test statistics. Sub-group, sensitivity analysis, and publication bias were performed.

RESULTS

Ten eligible studies consisting of 2979 study participants were included. The overall pooled prevalence of T. vaginalis infections in Ethiopia was 9.62%. Sub-group analysis showed that the overall pooled prevalence of T. vaginalis infections in pregnant women and other study groups was 6.68% and 12.86%, respectively. Publication bias was detected by funnel plots and Egger's tests.

CONCLUSIONS

This study showed that the overall pooled prevalence of T. vaginalis infections was relatively high. This study should trigger policy makers, governmental and non-governmental organizations, and healthcare providers to give attention for prevention and control of T. vaginalis infection.

Trichomoniasis, a new look at a common but neglected STI in African descendance population in the United States and the Black Diaspora. A review of its incidence, research prioritization, and the resulting health disparities

Structural racism plays a significant role in limited access to higher education, financial resources, employment opportunities, and high-quality healthcare for African Americans. The lack of healthcare equity and infrastructure has directly contributed to overall poor healthcare outcomes for the Black community. Studies have shown that adverse health outcomes such as sexually transmitted diseases (STDs) are more prevalent in African Americans, regardless of their socioeconomic factors and lifestyles. For example, trichomoniasis, transmitted sexually by its etiological agent, Trichomonas vaginalis (T. vaginalis), predisposes those infected to co-infections with other STDs, such as human immunodeficiency virus (HIV), herpes, and other related infections. Our review showcases the impact of trichomoniasis on the health of the Black community with an emphasis on African American women. A critical examination of the socio-demographic history of Black people in the United States (US) is vital to illustrate the origin of past and current racial health disparities. Further, we expand the complex and nuanced conversation on the intersectionality of racism, health equity, and innovative epidemiological and biomedical research strategies needed to eradicate this global public health threat.

First identification of telomeric DNA sequences in Trichomonas vaginalis

Trichomoniasis is the most common nonviral sexually transmitted disease; it is caused by Trichomonas vaginalis and seriously threatens human reproductive health. Telomeres are specialised DNA-protein complexes at the ends of chromosomes that have a protective function. The aim of the present study was to identify and characterise the telomeric DNA of T. vaginalis-which has not been previously reported-by multiple molecular methods including sequencing, the Bal nuclease (BAL) 31 nuclease assay, fluorescence in situ hybridisation (FISH), and Southern blotting. We found numerous repeated units of TTTTAGGG in T. vaginalis genomic DNA digested with S1 nuclease in combination with XbaI restriction enzyme. The (TTTTAGGG)_n tandem repeats were also highly sensitive to BAL 31 exonuclease digestion. We confirmed that the (TTTTAGGG)_n repeats were located at the end of T. vaginalis chromosomes by FISH. Restriction enzyme digestion combined with Southern blotting using a digoxigenin-labelled (TTTTAGGG)₅ probe showed that the T. vaginalis telomeric DNA length varied from 1.0 to 1.5 kb. This is the first report on the telomeric DNA sequence of T. vaginalis which includes the length and distribution on chromosomes; our findings lay a foundation for further study on telomere maintenance mechanisms in T. vaginalis.

Trichomonas vaginalis induces apoptosis via ROS and ER stress response through ER-mitochondria crosstalk in SiHa cells

Background

Trichomonas vaginalis causes lesions on the cervicovaginal mucosa in women; however, its pathogenesis remains unclear. We have investigated the involvement of the endoplasmic reticulum (ER) in the induction of apoptosis by T. vaginalis and its molecular mechanisms in human cervical cancer SiHa cells.

Methods

Apoptosis, reactive oxygen species (ROS) production, mitochondrial membrane potential (MMP), ER stress response and Bcl-2 family protein expression were evaluated using immunocytochemistry, flow cytometry, 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethyl-imidacarbocyanine iodide dye staining and western blotting.

Results

Trichomonas vaginalis induced mitochondrial ROS production, apoptosis, the ER stress response and mitochondrial dysfunction, such as MMP depolarization and an imbalance in Bcl-2 family proteins, in SiHa cells in a parasite burden- and infection time-dependent manner. Pretreatment with N-acetyl cysteine (ROS scavenger) or 4-phenylbutyric acid (4-PBA; ER stress inhibitor) significantly alleviated apoptosis, mitochondrial ROS production, mitochondrial dysfunction and ER stress response in a dose-dependent manner. In addition, T. vaginalis induced the phosphorylation of apoptosis signal regulating kinase 1 (ASK1) and c-Jun N-terminal kinases (JNK) in SiHa cells, whereas 4-PBA or SP600125 (JNK inhibitor) pretreatment significantly attenuated ASK1/JNK phosphorylation, mitochondrial dysfunction, apoptosis and ER stress response in SiHa cells, in a dose-dependent manner. Furthermore, T. vaginalis excretory/secretory products also induced mitochondrial ROS production, apoptosis and the ER stress response in SiHa cells, in a time-dependent manner.

Conclusions

Trichomonas vaginalis induces apoptosis through mitochondrial ROS and ER stress responses, and also promotes ER stress-mediated mitochondrial apoptosis via the IRE1/ASK1/JNK/Bcl-2 family protein pathways in SiHa cells. These data suggest that T. vaginalis-induced apoptosis is affected by ROS and ER stress response via ER–mitochondria crosstalk.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-021-05098-2.

Comprehensive characterization of purine and pyrimidine transport activities in Trichomonas vaginalis and functional cloning of a trichomonad nucleoside transporter

Trichomoniasis is a common and widespread sexually-transmitted infection, caused by the protozoan parasite Trichomonas vaginalis. T. vaginalis lacks the biosynthetic pathways for purines and pyrimidines, making nucleoside metabolism a drug target. Here we report the first comprehensive investigation into purine and pyrimidine uptake by T. vaginalis. Multiple carriers were identified and characterized with regard to substrate selectivity and affinity. For nucleobases, a high-affinity adenine transporter, a possible guanine transporter and a low affinity uracil transporter were found. Nucleoside transporters included two high affinity adenosine/guanosine/uridine/cytidine transporters distinguished by different affinities to inosine, a lower affinity adenosine transporter, and a thymidine transporter. Nine Equilibrative Nucleoside Transporter (ENT) genes were identified in the T. vaginalis genome. All were expressed equally in metronidazole-resistant and -sensitive strains. Only TvagENT2 was significantly upregulated in the presence of extracellular purines; expression was not affected by co-culture with human cervical epithelial cells. All TvagENTs were cloned and separately expressed in Trypanosoma brucei. We identified the main broad specificity nucleoside carrier, with high affinity for uridine and cytidine as well as purine nucleosides including inosine, as TvagENT3. The in-depth characterization of purine and pyrimidine transporters provides a critical foundation for the development of new anti-trichomonal nucleoside analogues.

Comparison of diagnostic methods and analysis of socio-demographic factors associated with Trichomonas vaginalis infection in Sri Lanka

BACKGROUND

Trichomonas vaginalis infection is underreported due to nonspecific clinical presentation and the nonavailability of sensitive laboratory diagnostic tests at the clinical setup. Hence, this study was designed to compare the sensitivity and specificity of microscopy and culture methods with polymerase chain reaction (PCR). The socio-demographic factors associated with the infection were explored.

METHODS

The study was carried out at the National Sexually Transmitted Diseases and Acquired Immuno Deficiency Syndrome Control Programme in Colombo and Sexually Transmitted Diseases and Acquired Immuno Deficiency Syndrome Control Programme in Kandy. Samples were collected from a total of 385 patients including, 272 females (70.7%) and 113 males (29.3%), and tested using microscopy (wet mount and Giemsa staining), culture, and PCR. Genus-specific primer set (TFR1/TFR2) that amplifies 5.8S rRNA and species-specific primer sets (TV16Sf-2/TV16Sr-2 and TVK3/7) that amplifies 18S rRNA and repetitive DNA, respectively, were used. Patient's socio-demographic and sexual behaviour data were obtained using a standard interviewer-administered questionnaire. Data were analyzed with R statistical software Version 3.6.3.

RESULTS

The overall prevalence of trichomoniasis was 4.4% (17/385). Of these, six (1.6%) were positive for microscopic examination, 7 (1.8%) were positive for culture, and 13 (3.4%) for TVK3/7, 15 (3.9%) for TV16Sf/r, and TFR1/2 17 (4.4%) were positive for PCR. Sensitivities of PCR using TFR1/2, TV16Sf/r, and TVK3/7 primer sets were 100%, 88.20%, and 76.50%, respectively, against the expanded gold standard. Trichomoniasis was associated with age above 36 (p = 0.033), not using condoms in last three months (p = 0.016), multiple sex partners (p = 0.001), reason for attendance (p = 0.027), symptomatic nature (p = 0.015), and the presence of other sexually transmitted diseases (p = 0.001).

CONCLUSIONS

The study highlighted that age over 36 years, multiple sex partners, not using condoms, reason for attendance, symptomatic nature, and having other sexually transmitted diseases can increase the risk of acquiring trichomoniasis. Furthermore, this study confirmed PCR as highly sensitive and specific diagnostic test for the diagnosis of trichomoniasis in comparison to microscopy and culture methods.

A review on Trichomonas vaginalis infections in women from Africa

Background

Trichomoniasis is the most common sexually transmitted infection (STI) with an estimated annual incidence of 276.4 million cases globally and about 30 million cases in sub-Saharan Africa. Trichomoniasis has been found to be associated with various health complications including pelvic inflammatory disease (PID), significant pregnancy complications, cervical cancer, prostatitis, infertility and the acquisition of human immunodeficiency virus (HIV).

Aim

Despite being a highly prevalent infection in the African continent, there is no review article published that solely focusses on Trichomonas vaginalis (T. vaginalis) infections in women from Africa. This review aims to fill this gap in the literature.

Method

An electronic search of online databases was used to identify and extract relevant research articles related to the epidemiology, health complications and treatment associated with T. vaginalis in women from Africa.

Results

Within the African continent, South Africa has reported the highest prevalence rate for this infection. A combination of sociodemographic, behavioural and biological factors has been shown to be associated with infection. Trichomonas vaginalis infection is associated with the acquisition of HIV, cervical cancer and PIDs in various female populations across the continent. Emerging patterns of resistance to metronidazole have been reported in women from South Africa. Currently, there is no effective vaccine against this pathogen despite efforts at vaccine development.

Conclusion

Based on the high prevalence and health consequences associated with T. vaginalis, there is a need for improved screening programmes that will lead to early diagnosis, detection of asymptomatic infections and effective treatment regimens.

Trichomonas vaginalis and growing concern over drug resistance: a systematic review

In the late 90s, a sharp increase of treatment failures of Trichomonas vaginalis (TV) infections with metronidazole (MTZ) was reported, representing a problem due to limited treatment options. We proposed to review the available evidence on the frequency of MTZ resistance by TV isolates and the relationship between treatment failure and in vitro resistance to MTZ. A systematic review based on the PRISMA guidelines was conducted by searching published studies in three different databases (PubMed, Scopus and Web of Science) up to December 2020. The extracted studies were uploaded to Covidence software; screening was guided based on inclusion and exclusion criteria. Additionally, different articles were included through other sources. For each article, study design, objectives, study population and key outcomes were summarized. We found 403 references from the databases and four extra studies. After duplicate removal and screening of title, abstract and full text, 27 studies were included. The selected studies were published between 1983 and 2019; all except one addressed only vaginal TV infection. We identified four major populations in vitro MTZ resistance: two studies evaluated female adolescents; other two assessed HIV-positive women. Fifteen studies considered MTZ resistance in newly diagnosed vaginal TV infection. Finally, eight articles studied in vitro susceptibility of isolates from women with clinical resistant trichomoniasis. High level of in vitro MTZ resistance was rare; low-moderate level was described in most of the cases. Although clinical resistance to MTZ of trichomoniasis was widely reported, there was a paucity of prospective controlled studies. Our review unveiled the need to standardize susceptibility testing, to define breakpoints for detection of MTZ-resistant isolates and to correlate with clinical outcome. It is important to establish criteria to define clinical resistance to MTZ. Such a consensus would foster the development of surveillance studies about clinical and microbiological response to MTZ treatment.

Distribution of genotypes in relation to metronidazole susceptibility patterns in Trichomonas vaginalis isolated from South African pregnant women

Reports on metronidazole resistance of Trichomonas vaginalis strains have been on the increase. This study investigated the in vitro metronidazole resistance patterns in T. vaginalis isolates obtained from South African pregnant women and the genotypes of these isolates. This study included 362 pregnant women recruited from a hospital in Durban, South Africa. The women provided self-collected vaginal swabs for the detection of T. vaginalis by culture in Diamonds media. Cultured isolates were then subjected to anaerobic susceptibility assays to metronidazole. For the genotyping assays, the actin gene was digested by HindII, MseI, and RsaI. The banding patterns obtained after digestion was used to determine the genotypes. A total of 21/362 (5.8%) pregnant women tested positive for T. vaginalis infection. Of the 21 T. vaginalis isolates tested for metronidazole susceptibility, 9.5% (2/21) had a minimum inhibitory concentration (MIC) of 4 μg/ml (resistant), 38.1% (8/21) had a MIC of 2 μg/ml (intermediate), and 52.4% (11/21) had a MIC ≤ 1 μg/ml (susceptible). The dominant genotype that was identified across the isolates was genotype G. There was no correlation between genotype harboured and metronidazole susceptibility patterns. In this study, resistance to metronidazole was observed in clinical isolates of T. vaginalis. This study did not find a correlation between genotype harboured and metronidazole susceptibility patterns. Despite the lack of association, our study provides data on an area of research that is currently lacking in our setting.

Gold(I) Phosphine Derivatives with Improved Selectivity as Topically Active Drug Leads to Overcome 5-Nitroheterocyclic Drug Resistance in Trichomonas vaginalis

Trichomonas vaginalis causes the most common, nonviral sexually transmitted infection. Only metronidazole (Mz) and tinidazole are approved for treating trichomoniasis, yet resistance is a clinical problem. The gold(I) complex, auranofin, is active against T. vaginalis and other protozoa but has significant human toxicity. In a systematic structure-activity exploration, we show here that diversification of gold(I) complexes, particularly as halides with simple C1-C3 trialkyl phosphines or as bistrialkyl phosphine complexes, can markedly improve potency against T. vaginalis and selectivity over human cells compared to that of the existing antirheumatic gold(I) drugs. All gold(I) complexes inhibited the two most abundant isoforms of the presumed target enzyme, thioredoxin reductase, but a subset of compounds were markedly more active against live T. vaginalis than the enzyme, suggesting that alternative targets exist. Furthermore, all tested gold(I) complexes acted independently of Mz and were able to overcome Mz resistance, making them candidates for the treatment of Mz-refractory trichomoniasis.

Latent Upregulation of Nlrp3, Nlrc4 and Aim2 Differentiates between Asymptomatic and Symptomatic Trichomonas vaginalis Infection

Trichomonas vaginalis is a parasitic protozoan that causes trichomoniasis. The involvement of NLRP3 inflammasome in trichomoniasis has been discussed in recent studies. The present study aimed to find out the involvement of Nlrp3, Nlrc4, and Aim2 in the BALB/c mouse model infected with symptomatic and asymptomatic isolates of T. vaginalis by quantitative real-time PCR and immunohistochemistry. Our results showed a significantly increased expression of Nlrp3 in the vaginal tissue of the symptomatic group on the 2^nd dpi and 14^th dpi in the asymptomatic group, respectively. The cervical tissue of asymptomatic groups expressed higher Nlrp3 on 14^th dpi than the symptomatic group. The Nlrc4 was expressed on 14^th dpi in the vaginal and cervical tissues of mice infected with asymptomatic group as compared to the symptomatic group. Aim2 expression in vaginal tissue was highest at early time points in both the infected groups as compared to controls. However, in cervical tissues, a significant increase of Aim2 expression was observed on 14^th dpi in asymptomatic as compared to the symptomatic group. The significantly higher expression of caspase-1 and caspase-4 was observed in cervical tissues of the asymptomatic group on 14^th dpi as compared to the symptomatic group, respectively. All NLRs together resulted in higher IL-1β expression in the vaginal tissues of the symptomatic and asymptomatic groups. We conclude from this study that early expression of Nlrp3, Nlrc4, and Aim2 was seen in the symptomatic group as compared to the late-onset asymptomatic in the vaginal and cervical tissues.

Microsatellite-Based Genotyping, Analysis of Population Structure, Presence of Trichomonas vaginalis Virus (TVV) and Mycoplasma hominis in T. vaginalis Isolates from Southwest of Turkey

Background:

The present study aimed to determine genetic diversity of Trichomonas vaginalis (T. vaginalis) isolates with microsatellite markers in Turkey (Nov 2015 to 2016) and to create a web-based microsatellite typing (MT) approach for the global interpretation of the data. In addition, the endosymbiosis of Mycoplasma hominis (M. hominis) and T. vaginalis virus (TVV) in the isolates was also examined.

Methods:

The allele sizes for each locus were calculated and microsatellite types were determined according to the allele profiles. The population structure was examined with Bayesian clustering method. A website (http://mttype.adu.edu.tr) was created for collection and sharing of microsatellite data. Presence of TVV and M. hominis in T. vaginalis isolates were investigated with electrophoresis and PCR.

Results:

Of 630 vaginal samples T. vaginalis was detected in 30 (4.7%) and those were used for further analysis. The structure produced by a clustering algorithm revealed eight genetic groups. The typing of isolates according to microsatellites revealed 23 different microsatellite types. Three clones were determined among isolates (MT10 16.7%; MT18 10% and MT3 6.7%). The frequency of TVV and M. hominis was 16.6% (n=5) and 20% (n=6), respectively.

Conclusion:

Presence of three clones among 30 T. vaginalis isolates indicated that microsatellite-based genotyping was efficient to determine the clonal distribution of T. vaginalis isolates. Therefore, a promising tool might be developed further and adapted to the studies dealing with molecular epidemiology of T. vaginalis. Microsatellite data from forthcoming studies will be deposited and presented on the website. In addition, we also presented the frequency of two endosymbionts in T. vaginalis isolates for the first time in Turkey.

In vitro trichomonocidal potency of Naja nigricollis and Bitis arietans snake venom

Background and Aim: Trichomonas vaginalis drug's limited efficacy and high toxicity, justify the need to explore other therapeutic agents, including animal toxins. In this study, the Naja nigricollis and Bitis arietans snake venoms were used to assess such trichomonocidal effect. Materials and Methods: The median lethal dose (LD50) value for both snake species was calculated by probit analysis using a statistical package for the sciences version 20.0 with an LD50 of 4.04 μg/mL for the N. nigricollis, and no mortality was observed in the B. arietans envenomed rats. Results: The trichomonocidal potency of the snake venom on T. vaginalis was evident with a growth inhibitory concentration of 89% with a half-maximal inhibitory concentration (IC50) of 0.805 μg/mL in B. arietans while 95% for N. nigricollis at an IC50 of 0.411 μg/mL. Conclusion: The statistical analysis of one-way analysis of variance shows a significant difference (p<0.05) between the venoms and positive control group (p<0.001), and there is no significant difference between each venom and its varying concentration (p>0.05). As the least concentration can be useful, interestingly, there is no significant difference in the efficacy of N. nigricollis and B. arietans to T. vaginalis (p>0.05); as such, either of the venom can be used for the treatment of trichomoniasis.

Recent Advances in Nanosystems and Strategies for Vaginal Delivery of Antimicrobials

Vaginal infections such as bacterial vaginosis (BV), chlamydia, gonorrhea, genital herpes, candidiasis, and trichomoniasis affect millions of women each year. They are caused by an overgrowth of microorganisms, generally sexually transmitted, which in turn can be favored by alterations in the vaginal flora. Conventional treatments of these infections consist in systemic or local antimicrobial therapies. However, in the attempt to reduce adverse effects and to contrast microbial resistance and infection recurrences, many efforts have been devoted to the development of vaginal systems for the local delivery of antimicrobials. Several topical dosage forms such as aerosols, lotions, suppositories, tablets, gels, and creams have been proposed, although they are sometimes ineffective due to their poor penetration and rapid removal from the vaginal canal. For these reasons, the development of innovative drug delivery systems, able to remain in situ and release active agents for a prolonged period, is becoming more and more important. Among all, nanosystems such as liposomes, nanoparticles (NPs), and micelles with tunable surface properties, but also thermogelling nanocomposites, could be exploited to improve local drug delivery, biodistribution, retention, and uptake in vulvovaginal tissues. The aim of this review is to provide a survey of the variety of nanoplatforms developed for the vaginal delivery of antimicrobial agents. A concise summary of the most common vaginal infections and of the conventional therapies is also provided.

Sexually Transmitted Infections in Pregnancy: An Update for Primary Care Providers

This article provides an overview of the incidence and prevalence of sexually transmitted infections in pregnant women in the United States. It discusses screening guidelines and best practices related to treatments. Safety, pharmacology, and monitoring of both the woman and her fetus are detailed.

Lack of association between Mycoplasma hominis and Trichomonas vaginalis symbiosis in relation to metronidazole resistance

Resistance mechanisms of Trichomonas vaginalis to metronidazole are still not well understood. It has been shown that Mycoplasma hominis has the ability to establish an endosymbiotic relationship with T. vaginalis. This study investigated the association between T. vaginalis and M. hominis symbiosis in relation to metronidazole resistance. This study included 362 pregnant women from the King Edward VIII hospital in South Africa. The women provided self-collected vaginal swabs for the diagnosis of T. vaginalis by culture. Metronidazole susceptibility using the broth-microdilution assay was performed. Detection of the 16S rRNA from M. hominis using T. vaginalis genomic DNA as the template was performed. All statistical analysis was conducted in R statistical computing software. A total of 21 culture positive isolates were obtained resulting in a prevalence of 5.8% for T. vaginalis in the study population. Under anaerobic incubation, 52.4% (11/21) of the isolates were susceptible to metronidazole (MIC ≤ 1 μg/ml). Intermediate resistance (MIC of 2 μg/ml) and full resistance (4 μg/ml) was observed in 38.1% (8/21) and 9.5% (2/21) of the isolates, respectively. The majority of the isolates 95% (19/20) were susceptible to metronidazole under aerobic conditions. Only one isolate had a MIC of 50 μg/ml. M. hominis was shown to be present in 85.7% (18/21) of the T. vaginalis isolates. However, there was no significant association between metronidazole susceptibility and T. vaginalis-M. hominis symbiosis. This study provides evidence of emerging metronidazole resistance in T. vaginalis. However, these resistance profiles were not associated with M. hominis symbiosis.

Sexually Transmitted Infections Part 2: Discharge Syndromes and Pelvic Inflammatory Disease

Sexually transmitted infections (STIs) disproportionately affect young people, with more than half of the infections occurring in youth aged 15 to 25 years. (1)(2) This review, the second in a 2-part series on STIs, focuses on infections that may cause abnormal vaginal or penile discharge, including trichomonas, chlamydia, gonorrhea, and pelvic inflammatory disease (PID). Most infected persons, however, are asymptomatic. Nucleic acid amplification tests are the most sensitive and specific for the detection of chlamydia, gonorrhea, and trichomoniasis, and they can be performed on provider- or patient-collected swabs. Providers should have a low threshold for diagnosing and treating PID because untreated PID can have serious long-term complications for young women. Indications for hospitalization for PID include the presence of a tubo-ovarian abscess, severe illness with systemic symptoms, pregnancy, human immunodeficiency virus infection, and failure to respond to outpatient oral treatment (within 48-72 hours) or inability to tolerate the oral treatment.

Barrier Protection Use by Adolescents During Sexual Activity

Rates of sexual activity, pregnancies, and births among adolescents have continued to decline during the past decade to historic lows. Despite these positive trends, many adolescents remain at risk for unintended pregnancy and sexually transmitted infections (STIs). This technical report discusses the new data and trends in adolescent sexual behavior and barrier protection use. Since 2017, STI rates have increased and use of barrier methods, specifically external condom use, has declined among adolescents and young adults. Interventions that increase availability of or accessibility to barrier methods are most efficacious when combined with additional individual, small-group, or community-level activities that include messages about safer sex. Continued research informs public health interventions for adolescents that increase the consistent and correct use of barrier methods and promote dual protection of barrier methods for STI prevention together with other effective methods of contraception.

Molecular-based Testing for Sexually Transmitted Infections Using Samples Previously Collected for Vaginitis Diagnosis

Background

Vaginal symptoms are a leading cause of primary care visits for women. Individuals exhibiting symptoms often receive laboratory testing based on clinic-specific standards of care. Thus, women seen at a family practice clinic might only receive a vaginitis workup, whereas those seen at a sexually transmitted diseases clinic could be more likely to receive only sexually transmitted infection (STI) testing.

Methods

The likelihood of STIs was assessed in women from whom samples were tested for vaginitis using a molecular diagnostic assay. Positivity rates for Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis DNA, detected using the BD MAX CT/GC/TV assay, were calculated. Concordance between the BD MAX Vaginal Panel and the BD MAX CT/GC/TV assay for detection of T. vaginalis was determined.

Results

Women with bacterial vaginosis alone or with concurrent Candida spp infections had high rates of coinfection with sexually transmitted infections (24.4%–25.7%); samples from women who were negative for vaginitis had significantly lower positivity rates (7.9%; P < .001). Trichomonas vaginalis results were concordant between the BD MAX Vaginal Panel and the BD MAX CT/GC/TV assay in 559 of 560 samples tested.

Conclusions

These data suggest, as have other studies, that women with vaginitis symptoms may be at risk for an STI. Molecular testing could provide broad diagnostic coverage for symptomatic women and improve patient management, regardless of the type of clinic in which patients are treated.

Prevalence and risk factors for Trichomonas vaginalis infection in pregnant women in South Africa

There are insufficient data on the prevalence of Trichomonas vaginalis infection in pregnant women in South Africa. The present study aims to determine the prevalence of T. vaginalis (TV) in pregnant women and identify the risk factors associated with this infection in pregnancy. This was a cross-sectional study which included 362 pregnant women attending the antenatal clinic at the King Edward VIII Hospital in Durban, South Africa. A self-collected vaginal swab was provided by the enrolled women for laboratory diagnosis by real-time polymerase chain reaction. The protozoan load was determined as the logarithm of gene copies per milliliter. The prevalence of TV infection was 12.9% and 59.6% of the women who tested positive were asymptomatic ( p =  0.011). Women who presented with abnormal vaginal discharge had a 4.6 times likelihood of testing positive for TV infection (odds ratio 4.62; 95% confidence interval 1.83 to 11.70; p =  0.001). TV infection was high amongst pregnant women. Therefore, routine testing for this sexually transmitted infection is encouraged for proper management.

Composite thermoresponsive hydrogel with auranofin-loaded nanoparticles for topical treatment of vaginal trichomonad infection

Trichomonas vaginalis is responsible for the most common non-viral sexually-transmitted disease worldwide. Standard treatment is with oral nitro-heterocyclic compounds, metronidazole or tinidazole, but resistance to these drugs is emerging and adverse effects can be problematic. Topical treatment offers potential benefits for increasing local drug concentrations and efficacy, while reducing systemic drug exposure, but no topical strategies are currently approved for trichomoniasis. The anti-rheumatic drug, auranofin (AF), was recently discovered to have significant trichomonacidal activity, but has a long plasma half-life and significant adverse effects. Here, we used this drug as a model to develop a novel topical formulation composed of AF-loaded nanoparticles (NP) embedded in a thermoresponsive hydrogel for intravaginal administration. The AF-NP composite gel showed sustained drug release for at least 12 h, and underwent sol-gel transition with increased viscoelasticity within a minute. Intravaginal administration in mice showed excellent NP retention for >6 h and markedly increased local AF levels, but reduced plasma and liver levels compared to oral treatment with a much higher dose. Furthermore, intravaginal AF-NP gel greatly outperformed oral AF in eliminating vaginal trichomonad infection in mice, while causing no systemic or local toxicity. These results show the potential of the AF-NP hydrogel formulation for effective topical therapy of vaginal infections.

20S Proteasome as a Drug Target in Trichomonas vaginalis

Trichomoniasis is a sexually transmitted disease with hundreds of millions of annual cases worldwide. Approved treatment options are limited to two related nitro-heterocyclic compounds, yet resistance to these drugs is an increasing concern. New antimicrobials against the causative agent, Trichomonas vaginalis, are urgently needed. We show here that clinically approved anticancer drugs that inhibit the proteasome, a large protease complex with a critical role in degrading intracellular proteins in eukaryotes, have submicromolar activity against the parasite in vitro and on-target activity against the enriched T. vaginalis proteasome in cell-free assays. Proteomic analysis confirmed that the parasite has all seven α and seven β subunits of the eukaryotic proteasome although they have only modest sequence identities, ranging from 28 to 52%, relative to the respective human proteasome subunits. A screen of proteasome inhibitors derived from a marine natural product, carmaphycin, revealed one derivative, carmaphycin-17, with greater activity against T. vaginalis than the reference drug metronidazole, the ability to overcome metronidazole resistance, and reduced human cytotoxicity compared to that of the anticancer proteasome inhibitors. The increased selectivity of carmaphycin-17 for T. vaginalis was related to its >5-fold greater potency against the β1 and β5 catalytic subunits of the T. vaginalis proteasome than against the human proteasome subunits. In a murine model of vaginal trichomonad infection, proteasome inhibitors eliminated or significantly reduced parasite burden upon topical treatment without any apparent adverse effects. Together, these findings validate the proteasome of T. vaginalis as a therapeutic target for development of a novel class of trichomonacidal agents.

Prevalence and cervical organism burden among Louisiana women with Trichomonas vaginalis infections

Trichomonas vaginalis is the most common curable sexually transmitted infection (STI) worldwide. Although predominately asymptomatic, the disease spectrum of trichomoniasis in women is characterized primarily by signs and symptoms of vaginitis, including purulent discharge and localized vulvar pruritus and erythema. Several FDA-cleared nucleic acid amplification tests (NAATs) are available for the diagnosis of T. vaginalis infections, but laboratory developed tests (LDTs) are widely utilized and cost-effective solutions in both the research and clinical diagnostic settings. LDT diagnosis of T. vaginalis is particularly appealing since it can be performed using remnant specimens collected for other STI testing. Using a LDT implemented as part of this study, T. vaginalis was detected in 7% of participating Louisiana women (14/199). The mean T. vaginalis organism burden was 1.0x10⁶ ± 4.5x10⁵ organisms per mL of ThinPrep PreservCyt. Using DNA eluates obtained after HPV testing on the cobas 4800 system, the T. vaginalis LDT was characterized by excellent intra- and interassay reproducibility (coefficient of variation values all <3.5%). Compared with two commercially available NAATs from TIB MOLBIOL, the sensitivity and specificity of the LDT was 92.9 and 99.5%, respectively. Collectively, this study details the diagnostic and quantitative utility of a LDT for T. vaginalis. When applied in the clinical research setting, we confirmed the high prevalence of T. vaginalis, but also observed extraordinarily high organism burdens in the cervix. These findings highlight the unique host-pathogen relationship of T. vaginalis with lower reproductive tract tissues, and substantiate the need for continued investigation of this highly prevalent STI.

Treatment Attitudes for Belgian Women With Persistent Trichomonas vaginalis Infection in the VlaResT Study

BACKGROUND

Because of its increasing prevalence worldwide, its sexual transmissibility and its facilitation of human immunodeficiency virus transmission, Trichomonas vaginalis (TV) infection constitutes an important public health concern.

THE AIM OF THE STUDY

While searching for possible resistant TV cases, adequacy of management of TV-infected women was assessed.

METHODS

Cervical cytology between July 2007 and July 2014 was tested with TV polymerase chain reaction, and 304 women expressed repeatedly positive results, 718 in total. For each of these positive results, a questionnaire about treatment decisions was sent to the 182 Belgian physicians treating these women.

RESULTS

From the 346 returned questionnaires by their physician it was evident that 58.1% of women with repeatedly positive TV had received no treatment. TV was overlooked in 31.5%, and in 17.6% the test result was seen but ignored. Upon seeing the positive result, 23.9% of physicians decided that this finding was not important enough to institute treatment, and/or requested confirmatory tests. Adequate treatment was prescribed in 38.4%. Retreatment after failed therapy was given in only 29.3% of the cases. And 60% of the partners of women with persistent TV infection were not traced, nor treated.

CONCLUSION

Most of the repeatedly positive TV infection may not be due to antibiotics resistance. The low awareness, poor attention, failure of contact tracing, and low rates of proper treatment provided by treating physicians question the adequacy of the current management of TV infection and requires renewed education campaigns and increased surveillance.

A Study of Trichomonas vaginalis Infection and Correlates in Women with Vaginal Discharge Referred at Fann Teaching Hospital in Senegal

INTRODUCTION

Trichomoniasis is nowadays the most prevalent non-viral sexually transmitted infection in the world. In Senegal, the epidemiology of trichomoniasis is not well known. The current study aimed at assessing the prevalence and factors associated with T. vaginalis infection among women with vaginal discharge.

METHODS

A retrospective analysis of laboratory records from patients referred at the Fann Teaching Hospital in Dakar, Senegal, for vaginal discharge was carried out. The study covered the period from 2006 to 2011. For each participating woman, a vaginal swab was collected and a wet mount smear performed immediately. Optic microscopic examination with 40x magnification was done to detect T. vaginalis and assess biological modifications such as presence of epithelial cells, white blood cells, and red blood cells. A gram stained smear was also performed and examined under oil immersion (100x magnification) to assess the vaginal flora.

RESULTS

Overall, 3893 women were enrolled with a mean age at 31.2 ± 10 years. The prevalence of Trichomoniasis represented 4.8%, 95%CI(3.1-5.7) and it was lower among women less than 30 years (4.1%), while divorced women more likely to be infected compared to married and single women (aOR:2.1, 95%CI (1.2-3.7)). Trichomoniasis was associated with abnormal vaginal flora such as type III (aOR:2.6, 95%CI(1.5-4.4)) and type IV (aOR:3.3, 95%CI(2.1-5.3)). In addition, patients with erythrocytes excretion were more likely to be infected by T. vaginalis (aOR:2.8, 95%CI(1.9-3.9).

CONCLUSION

Trichomonas vaginalis remains prevalent among sexually active women. Strategies aiming at improving disease awareness in these high-risk groups are needed to improve trichomoniasis prevention but extensive epidemiological data are still needed for a better understanding of the disease transmission dynamic.

Chlorinated metronidazole as a promising alternative for treating trichomoniasis

Trichomoniasis is the most common non-viral, sexually transmitted infection affecting humans worldwide. The main treatment for trichomoniasis is metronidazole (MTZ). However, adverse effects and reports of resistance have stimulated the development of therapeutic alternatives. The ease of manipulation of the side chains of MTZ coupled with its safety makes this molecule attractive for the development of new drugs. In this context, we evaluated the activity of the chlorinated MTZ derivative, MTZ-Cl, on sensitive and resistant strains of Trichomonas vaginalis. MTZ-Cl presented a remarkable activity against both sensitive and resistant strains. In vitro and in vivo toxicity assays indicated that the new molecule is safe for future clinical trials. Furthermore, we noticed different rates of free radical production between the sensitive and resistant strains. MTZ-Cl induced a higher release of nitric oxide (NO, ~ 9000 a.u.) by both sensitive and resistant strains. However, the sensitive strain produced a greater amount of H₂O₂ (~ 1,800,000 a.u.) and superoxide radicals (~ 350,000 a.u.) in the presence of MTZ. In the resistant strain, production of these radicals was more prominent when MTZ-Cl was used. Collectively, these results suggest that NO is an important molecule in the trichomonacidal activity against resistant and sensitive strains, suggesting an alternative pathway for MTZ-Cl activation. We highlight the high trichomonacidal potential of MTZ-Cl, improving the effectiveness of treatment and reducing side effects. In addition, MTZ-Cl is derived from a well-established drug on the world market that presents low toxicity to human cells, suggesting its safety to proceed with future clinical trials.

The Prevalence of Trichomoniasis in Women Referred to Clinical Centers in South of Tehran, Iran during 2015-2016

BACKGROUND

This study aimed to estimate the prevalence of trichomoniasis infection among females in Tehran, Iran.

METHODS

This study was conducted on 482 women referred to the 6 obstetrics and gynecology centers of Tehran during 2015-2016. Some information including education, occupation, and number of sexual partners was obtained and clinical signs and symptoms of the genital tract were diagnosed by clinical examination. Two swabs were collected from the posterior fornix of patients. Two laboratory techniques, wet mount, and culture were carried out. Finally, statistical analysis test was performed using SPSS software version 16.0.

RESULTS

Age distribution of patients was 15-60 yr. Trichomonas vaginalis was detected in 2 out of 482 participants (0.41%). All of the infected individuals were married (0.43%) and they had unique sexual partner and all of them had clinical symptoms. Significant association was observed between incidence of T. vaginalis infection and educational levels (P= 0.03), occupation (P=0.006), clinical symptoms (P=0.001), marriage (P=0.006) and bacterial infection (P=0.018).

CONCLUSION

The prevalence of trichomoniasis was low and its incidence was associated with several risk factors.

Prevalence of Trichomonas vaginalis infection and protozoan load in South African women: a cross-sectional study

OBJECTIVES

Trichomonas vaginalis is thought to be the most common non-viral sexually transmitted infection worldwide. We investigated the prevalence, risk factors and protozoan load of T. vaginalis infection in South African women.

METHODS

A cross-sectional study of 604 women was conducted at 25 primary healthcare facilities in rural South Africa (Mopani district). T. vaginalis DNA was detected in vaginal and rectal swabs. In univariate and multivariate analyses, the T. vaginalis infection was investigated in relation to demographic characteristics, medical history and behavioural factors. The T. vaginalis load was determined as the logarithm of DNA copies per microlitre sample solution.

RESULTS

Collected vaginal and rectal swabs were tested for T. vaginalis DNA. Prevalence of vaginal T. vaginalis was 20% (95% CI 17.0% to 23.4%) and rectal 1.2% (95% CI 0.6% to 2.4%). Most women (66%) with a vaginal infection were asymptomatic. Factors associated with T. vaginalis infection were a relationship status of single (OR 2.4; 95% CI 1.5 to 4.0; p<0.001) and HIV positive infection (OR 1.6; 95% CI 1.0 to 2.6; p=0.041). Women with vaginal T. vaginalis infection were more likely to have concurrent Chlamydia trachomatis rectal infection than those without vaginal infection (12%vs3%; p<0.001; OR 4.1). A higher median T. vaginalis load was observed among women with observed vaginal discharge compared with those without vaginal discharge (p=0.025).

CONCLUSIONS

Vaginal trichomoniasis is highly prevalent in rural South Africa, especially among single women and those with HIV infection, and often presents without symptoms.

Detecting the Diversity of Mycoplasma and Ureaplasma Endosymbionts Hosted by Trichomonas vaginalis Isolates

Objectives: The symbiosis of Trichomonas vaginalis and Mycoplasma hominis is the first described association between two obligate human parasites. Trichomonas is the niche and the vector for the transmission of M. hominis infection. This clinically significant symbiosis may affect T. vaginalis virulence and susceptibility to treatment. The aims of this study were to investigate the intracellularly present Mycoplasma and Ureaplasma species in T. vaginalis strains isolated from the vaginal discharge of infected women as well as to trace the diversity pattern among the species detected in the isolated strains. Methods: Hundred pure T. vaginalis cultures were isolated from ~7,500 patient specimens presented with clinical purulent vaginitis. PCR and sequencing for Mycoplasma/Ureaplasma spp. were performed in DNA extracted from the pure cultures. In addition, vaginal discharge samples were cultured for the presence of M. hominis and U. urealyticum. Phylogenetic analysis assisted the identification of interspecies relationships between the Mycoplasma and Ureaplasma isolates. Results: Fifty four percentage of T. vaginalis isolates were harboring Mycoplasma spp. Phylogenetic analysis revealed three distinct clusters, two with already characterized M. hominis and Ureaplasma spp. (37% of total Mycoplasma spp.), whereas one group formed a distinct cluster matched with the newly identified species Candidatus Mycoplasma girerdii (59.3%) and one or more unknown Mycoplasma spp. (3.7%). Conclusions:T. vaginalis strains associated with vaginal infection might host intracellular mycoplasmas or ureaplasmas. Intracellular Mollicutes that remain undetected in the extracellular environment when conventional diagnostic methods are implemented may comprise either novel species, such as Candidatus M. giredii, or unknown species with yet unexplored clinical significance.

Profile of the triplex assay for detection of chlamydia, gonorrhea and trichomonas using the BD MAX™ System

INTRODUCTION

Chlamydia, gonorrhea and trichomonas are the most common curable STI. improved access to testing could reduce infection rates and prevent sequelae. nucleic acid amplification tests are the recommend class of diagnostic assay for these infections which are often asymptomatic. Areas covered: A description of the BD MAX™ System (MAX) and the BD MAX CT/GC/TV assay is provided along with data from a large US clinical trial. The capacity of the system for other tests and for lab developed assays is also described. Expert commentary: The CT/GC/TV assay on the MAX is a triplex PCR assay suitable for use with female urine and vaginal or endocervical swab samples. Male urine can be tested by ordering the CT/GC results but has not yet been evaluated for trichomonas. The assay performance characteristics are similar to those of assays run on high-throughput platforms with sensitivity ≥91.5% and specificity ≥98.6% for all analytes. Screening with the CT/GC/TV assay can be combined with testing for vaginitis which would provide a greater depth of coverage for common co-infections. The throughput is moderate (1-48 samples per 8-hour shift) but the menu includes assays beyond STI pathogens making this a suitable platform for moderate volume laboratories.

Single-Dose Compared With Multidose Metronidazole for the Treatment of Trichomoniasis in Women: A Meta-Analysis

BACKGROUND

Trichomonas vaginalis is the most common curable sexually transmitted infection worldwide. Although the Centers for Disease Control and Prevention and the World Health Organization recommend a single 2-g dose of metronidazole for the first line of treatment for T. vaginalis among human immunodeficiency virus (HIV) negative women, high rates of repeat infections are found. The purpose of this meta-analysis was to compare treatment failure between single versus multidose metronidazole for the treatment of T. vaginalis.

METHODS

A systematic literature search was performed using search terms including metronidazole AND trichomoniasis AND women. Embase, MEDLINE, and Clinicaltrials.gov were used to search for relevant studies as well as hand searching relevant articles. These databases were last searched on January 25, 2016. To be included in this meta-analysis, the study had to be a clinical trial, evaluate T. vaginalis, use oral metronidazole, and compare single dose metronidazole to multidose metronidazole.

RESULTS

There were 487 articles that were assessed for relevance and quality. Of these articles, 6 met the eligibility criteria and were included in the final results. The pooled risk ratio indicated higher treatment failure for single dose compared to multidose 1.87 (95% confidence interval, 1.23-2.82; P < 0.01). When the one study that included HIV+ women was excluded from analysis, the findings were similar with a pooled risk ratio of 1.80 (95% confidence interval, 1.07-3.02; P < 0.03).

CONCLUSIONS

Centers for Disease Control and Prevention recently changed treatment recommendations for HIV+ women to multidose rather than single-dose. These data suggest that those recommendations should be considered for all women.

Clinical Recommendation: Vulvovaginitis

Vulvovaginitis is a commonly encountered condition among prepubertal and adolescent females. The objective of this report is to provide the latest evidence regarding the diagnosis and management of vulvovaginitis in prepubertal and adolescent females. In this systematic review we used the Grading of Recommendations Assessment, Development and Evaluation evidence system. Vulvovaginal complaints are common in the pediatric and adolescent age group. The patient's age in conjunction with history and associated complaints will guide evaluation, diagnosis, and treatment. Treatment should include counseling on hygiene and voiding techniques as well as therapy for any specific pathogens identified.

Antiprotozoal Effects of the Tomato Tetrasaccharide Glycoalkaloid Tomatine and the Aglycone Tomatidine on Mucosal Trichomonads

The present study investigated the inhibitory effects of the commercial tetrasaccharide tomato glycoalkaloid tomatine and the aglycone tomatidine on three mucosal pathogenic protozoa that are reported to infect humans, cattle, and cats, respectively: Trichomonas vaginalis strain G3, Tritrichomonas foetus strain D1, and Tritrichomonas foetus strain C1. A preliminary screen showed that tomatine at 100 μM concentration completely inhibited the growth of all three trichomonads. In contrast, the inhibition of all three pathogens by tomatidine was much lower, suggesting the involvement of the lycotetraose carbohydrate side chain in the mechanism of inhibition. Midpoints of concentration-response sigmoid plots of tomatine on the three strains correspond to IC₅₀ values, the concentration that inhibits 50% of growth of the pathogenic protozoa. The concentration data were used to calculate the IC₅₀ values for G3, D1, and C1 of 7.9, 1.9, and 2.2 μM, respectively. The results show an approximately 4-fold variation from the lowest to the highest value (lowest activity). Although the inhibition by tomatine was not as effective as that of the medicinal drug metronidazole, the relatively low IC₅₀ values for both T. vaginalis and T. foetus indicated tomatine as a possible natural alternative therapeutic for trichomoniasis in humans and food-producing (cattle and pigs) and domestic (cats) animals. Because tomatine has the potential to serve as a new antiprotozoan functional (medical) food, the distribution of this glycoalkaloid in tomatoes and suggestions for further research are discussed.

Trichomonas vaginalis and Human Immunodeficiency Virus Coinfection Among Women Under Community Supervision: A Call for Expanded T. vaginalis Screening

BACKGROUND

The United States has a large community supervision population, a growing number of whom are women. Trichomonas vaginalis infection is strongly associated with an increased risk of human immunodeficiency virus (HIV) acquisition and transmission, particularly among women, but there is a paucity of research on HIV and T. vaginalis co-infection among women under community supervision.

METHODS

This article examines the prevalence of T. vaginalis infection and T. vaginalis and HIV coinfection at baseline among women under community supervision in New York City. It also examines the 12-month outcomes of women treated for T. vaginalis. Women received biological tests for HIV and T. vaginalis at baseline and 12 months follow-up.

RESULTS

Of the 333 women tested for sexually transmitted infections, 77 women (23.1%) tested positive for T. vaginalis at baseline and 44 (13.3%) were HIV positive. Human immunodeficiency virus-positive women had significantly higher rates of T. vaginalis infection than HIV-negative women (36.4% vs 21.3%, P ≤ 0.05). Sixteen women (4.8%) were coinfected with T. vaginalis and HIV. Of the 77 women who were positive for T. vaginalis infection at baseline, 58 (75.3%) received treatment by a health care provider. Of those who received treatment, 17 (29.3%) tested positive for T. vaginalis at the 12-month follow-up.

CONCLUSIONS

Given the high prevalence of T. vaginalis among this sample of women, particularly among HIV-positive women, and high levels of reinfection or persistent infection, screening for T. vaginalis among women under community supervision may have a substantial impact on reducing HIV acquisition and transmission among this high-risk population.

Trichomoniasis - are we giving the deserved attention to the most common non-viral sexually transmitted disease worldwide?

ETIOLOGY

Trichomonas vaginalis is the etiologic agent of trichomoniasis, the most common non-viral sexually transmitted disease (STD) in the world. Transmission: Trichomoniasis is transmitted by sexual intercourse and transmission via fomites is rare. Epidemiology, incidence and prevalence: The WHO estimates an incidence of 276 million new cases each year and prevalence of 187 million of infected individuals. However, the infection is not notifiable. Pathology/Symptomatology: The T. vaginalis infection results in a variety of clinical manifestations - in most cases the patients are asymptomatic, but some may develop signs typically associated to the disease. Importantly, the main issue concerning trichomoniasis is its relationship with serious health consequences such as cancer, adverse pregnancy outcomes, infertility, and HIV acquisition. Molecular mechanisms of infection: To achieve success in parasitism trichomonads develop a complex process against the host cells that includes dependent- and independent-contact mechanisms. This multifactorial pathogenesis includes molecules such as soluble factors, secreted proteinases, adhesins, lipophosphoglycan that culminate in cytoadherence and cytotoxicity against the host cells. Treatment and curability: The treatment with metronidazole or tinidazole is recommended; however, cure failures remain problematic due to noncompliance, reinfection and/or lack of treatment of sexual partners, inaccurate diagnosis, or drug resistance. Therefore, new therapeutic alternatives are urgently needed. Protection: Strategies for protection including sexual behavior, condom usage, and therapy have not contributed to the decrease on disease prevalence, pointing to the need for innovative approaches. Vaccine development has been hampered by the lack of long-lasting humoral immunity associated to the absence of good animal models.

OsmC and incomplete glycine decarboxylase complex mediate reductive detoxification of peroxides in hydrogenosomes of Trichomonas vaginalis

Osmotically inducible protein (OsmC) and organic hydroperoxide resistance protein (Ohr) are small, thiol-dependent peroxidases that comprise a family of prokaryotic protective proteins central to the defense against deleterious effects of organic hydroperoxides, which are reactive molecules that are formed during interactions between the host immune system and pathogens. Trichomonas vaginalis, a sexually transmitted parasite of humans, possesses OsmC homologues in its hydrogenosomes, anaerobic mitochondrial organelles that harbor enzymes and pathways that are sensitive to oxidative damage. The glycine decarboxylase complex (GDC), which consists of four proteins (i.e., L, H, P and T), is in eukaryotes exclusively mitochondrial enzymatic system that catalyzes oxidative decarboxylation and deamination of glycine. However, trichomonad hydrogenosomes contain only the L and H proteins, whose physiological functions are unknown. Here, we found that the hydrogenosomal L and H proteins constitute a lipoate-dependent redox system that delivers electrons from reduced nicotinamide adenine dinucleotide (NADH) to OsmC for the reductive detoxification of peroxides. Our searches of genome databases revealed that, in addition to prokaryotes, homologues of OsmC/Ohr family proteins with predicted mitochondrial localization are present in various eukaryotic lineages. Therefore, we propose that the novel OsmC-GDC-based redox system may not be limited to T. vaginalis.

Clinical and Laboratory Testing for Trichomonas vaginalis Infection

Trichomonas vaginalis infection is highly prevalent in the United States and worldwide. Traditional clinical diagnostic methods fail to identify more than half of these infections that, if left untreated, can result in adverse pregnancy outcomes and an exacerbated risk of both acquisition and transmission of HIV. Women bear a disproportionate amount of the burden of these infections, and testing among populations at risk for this disease should be provided. Molecular technologies have expanded our capacity for laboratory-based detection of infection and can be used on samples already being collected for chlamydia/gonorrhea screening.