Search Results (129)

Sexually transmitted infections remain a major public health concern among men who have sex with men (MSM), particularly due to the high frequency of coinfections and the limitations of syndromic management. This study aimed to describe the frequency of bacterial sexually transmitted and urogenital pathogens among symptomatic MSM attending two specialized sexual health clinics in Mexico City. A prospective cross-sectional study was conducted with 150 adult MSM presenting symptoms suggestive of urethritis. Urethral swab samples were analyzed using a multiplex real-time polymerase chain reaction (PCR) assay for the detection of Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma urealyticum, Ureaplasma parvum, and Trichomonas vaginalis. At least one pathogen was detected in 91/150 participants (60.7%). N. gonorrhoeae was the most frequent pathogen (33.3%), followed by U. urealyticum (15.3%), M. genitalium (9.3%), and C. trachomatis (9.3%). Coinfections were identified in 15 participants, representing 10.0% of the total population and 16.5% of those with a positive PCR result. Most coinfections involved N. gonorrhoeae, particularly with C. trachomatis. These findings provide descriptive microbiological evidence on the frequency and coinfection patterns of bacterial sexually transmitted infections (STIs) associated pathogens among symptomatic MSM attending specialized sexual health clinics in Mexico City. The high detection rate and occurrence of concurrent infections highlight the limitations of syndromic management and support the value of timely multiplex molecular diagnostics to improve etiological characterization, antimicrobial stewardship, and clinical decision-making in this population. Full article

As part of efforts to identify genes associated with Trichomonas vaginalis resistance to 5-nitroimidazole drugs, thirty cryopreserved T. vaginalis isolates were revived and grown using Diamond’s TYM medium. Minimum lethal concentrations (MLCs) for metronidazole (MTZ), tinidazole (TDZ), and secnidazole (SEC) were determined using a drug susceptibility assay. Transcriptome profiling was performed for 15 MTZ-sensitive (MTZ-S, MLC < 50 µg/mL) and 15 MTZ-resistant (MTZ-R, MLC ≥ 50 µg/mL) isolates using next-generation RNA sequencing. Bioinformatics analyses identified differentially expressed genes (DEGs). Among the MTZ-R isolates, six exhibited low MLCs of 50 µg/mL, five had intermediate MLCs between 100 and 200 µg/mL, and four had high MLCs ≥ 400 µg/mL. Differential gene expression analysis identified 28, 140, and 73 significantly altered genes in low-, intermediate-, and high-level MTZ resistance groups, respectively, with predominantly upregulated expression patterns. The SEC-resistant (SEC-R) isolates exhibited 136 differentially expressed genes, whereas the TDZ-resistant (TDZ-R) isolates showed minimal transcriptional changes. Focused analyses of iron transport pathways revealed reduced expression of ZIP-family iron import genes, particularly TvZIP4 (TVAG_273550), the strongest predictor of resistance in elastic-net modeling (AUC = 0.795). Resistant isolates also demonstrated coordinated upregulation of iron–sulfur cluster assembly and hydrogenosomal protein-import pathways. Weighted gene co-expression network analysis (WGCNA) identified multiple resistance-associated transcriptional modules correlated with MTZ and SEC MLCs. A comparative transcriptomic–proteomic analysis revealed concordant upregulation of iron–sulfur cluster machinery but discordant regulation of hydrogenosomal cargo proteins, likely supporting a post-transcriptional restriction model. These findings provide a broader mechanistic framework for understanding 5-nitroimidazole resistance in T. vaginalis and identifying candidate biomarkers and pathways that may support future therapeutic and diagnostic development. Full article

Background/Objectives: Trichomonas vaginalis is one of the most prevalent non-viral sexually transmitted infections worldwide. Although Gram staining is routinely performed in clinical microbiology laboratories for the evaluation of vaginal samples, it is not considered a diagnostic method for T. vaginalis, which represents a missed diagnostic opportunity in routine practice. This study aimed to evaluate an artificial intelligence (AI)-assisted diagnostic approach for the identification of T. vaginalis directly from routine Gram-stained vaginal smears. Methods: A retrospective dataset of Gram-stained vaginal smear images was analysed using a cascaded AI-based framework combining image processing and classification. The image selection and quality control were performed under the supervision of a specialised clinical microbiologist. All cases were independently confirmed by polymerase chain reaction (PCR), which served as the reference diagnostic standard. Model performance was assessed using standard diagnostic metrics, including accuracy, sensitivity, specificity, area under the receiver operating characteristic curve (AUC), Cohen’s kappa, and Matthews correlation coefficient (MCC). Held-out independent testing was used to assess generalisability beyond the internal validation subset. Results: The proposed AI-assisted approach demonstrated high diagnostic performance for the identification of T. vaginalis, achieving an AUC of 0.973, Cohen’s kappa of 0.87, and an MCC of 0.87. The system showed high diagnostic concordance with PCR results across both internal and external validation datasets, supporting the feasibility and reproducibility of the approach under routine laboratory conditions. Conclusions: This study shows that artificial intelligence may enhance the diagnostic utility of routinely performed Gram-stained vaginal smears by enabling reliable identification of T. vaginalis. The proposed approach could be integrated into standard microbiology workflows as an objective decision-support or triage adjunct, facilitating early identification and supporting clinical decision-making without altering existing laboratory procedures. Full article

Cannonballs, compact aggregates of neutrophils observed in Papanicolaou (Pap) smears, are frequently associated with Trichomonas vaginalis (T. vaginalis) infection but are generally regarded as nonspecific inflammatory findings. To clarify their morphologic features, we analyzed cervicovaginal liquid-based cytology specimens from 29 cervicitis cases, including six positive for T. vaginalis. Cannonballs were evaluated using immunocytochemistry for T. vaginalis and cytokeratin, cell block analysis, and morphometric analysis, with negative cases as controls. All positive cases contained T. vaginalis-associated cannonballs, with a mean positivity rate of 57.4%. Parasites were intermingled with aggregated neutrophils, and cell block analysis demonstrated parasite-centered neutrophilic aggregates. Cytokeratin staining patterns differed morphologically between positive and negative cases. In addition, T. vaginalis-associated cannonballs were significantly smaller than adjacent squamous epithelial cells. These findings suggest that some cannonballs in trichomoniasis may represent parasite-associated neutrophilic structures and provide insight into host–parasite interactions in cervicovaginal inflammation. Full article

Chagas disease and trichomoniasis are two neglected parasitic infections (NPIs) in need for new therapies that address both the toxicity and limited bioavailability impacting on the effectiveness of benznidazole (BZ) and nifurtimox, the only drugs available for treating the infection caused by Trypanosoma cruzi, as well as the resistance that Trichomonas vaginalis has developed to 5-nitroimidazoles. Herein, we report the outcomes of the primary screening of a series of eighteen quinoxaline-1,4-di-N-oxides (QdNOs) carried out against both protozoan parasites. Computational approaches revealed that these derivatives have adequate oral bioavailability and do not pose toxicity risks associated with their chemical structures. Meanwhile, biological studies disclosed that compounds 4b and 4m exhibit considerable activity against T. cruzi at the highest concentration tested, showing 4m a trypanocidal profile (IC₅₀ = 23.66 µM) similar to that of BZ (IC₅₀ = 21.66 µM), and a selectivity index (SI) > 5.32. Regarding the activity on T. vaginalis, derivative 4n stands out with an IC₅₀ value of 9.85 µM, showing no cytotoxicity towards mammalian cells. However, their potency decreases when tested over resistant parasites. Alterations in either the hydrogenosomal membrane potential or the production of reactive oxygen species (ROS) were also explored. The findings suggest that the trichomonacidal activity of compound 4n is not mediated by a direct disruption of hydrogenosomal bioenergetics or a pro-oxidant effect. Altogether, these preliminary results support that the QdNO scaffold could be introduced as a proper template for developing novel trypanocidal and trichomonacidal agents. Full article

Sexually transmitted diseases (STDs) continue to represent a substantial burden on public health and society worldwide. With significant implications for social, economic, and public health, STDsare a major global health concern. Despite advances in treatment, the global control of STDs is increasingly threatened by high prevalence of asymptomatic infections, delayed diagnosis and the rapid emergence of antimicrobial resistance (AMR). This emergence includes the value of asymptomatic screeningand the ensuing collateral damage resulting from the overuse of our declining potent antimicrobial resources. This review article critically examines current trends in the epidemiology, clinical significance, and laboratory diagnosis of major sexually transmitted pathogens, including Treponema pallidum, Chlamydia trachomatis, Trichomonas vaginalis, human papillomavirus, herpes simplex virus, and emerging sexually transmissible infections. Major emphasis is focused on contemporary diagnostic technologies and strategies, with a major focus on nucleic acid-based and point-of-care testing and their applicability in routine testing. The review also highlights evolving AMR patterns, resistance-guided therapy, and the role of global and national surveillance systems in informing treatment guidelines, with the integration of diagnostic strategies with resistance-guided therapy and surveillance systems. Strengthening diagnostic capacity, antimicrobial stewardship, and integrated surveillance is essential to mitigate resistance, improve patient outcomes, and advance effective STD management in venereology practice. Full article

Trichomonas vaginalis is the causative agent of trichomoniasis, the most common non-viral sexually transmitted infection worldwide. In these cases, 5-Nitroimidazoles, particularly metronidazole (MTZ), remain the primary treatment option; however, resistance to MTZ has been increasingly reported. This study aimed to evaluate the in vitro activity of D-form synthetic antimicrobial peptides and investigate transcriptional differences associated with MTZ resistance and peptide treatment in T. vaginalis. D-form synthetic peptides (D-TN1, D-TN3, and D-TN6) developed in the R&D Laboratory of Acibadem University were tested against metronidazole-susceptible (T. vaginalis ATCC 30236) and metronidazole-resistant (T. vaginalis ATCC 50143) strains by minimum lethal concentration (MLC) assays. D-TN1 exhibited an MLC of 16 µg/mL in both strains, whereas D-TN3 and D-TN6 exhibited MLC values of 32 µg/mL and 16–32 µg/mL, respectively. Comparative transcriptomic analysis was conducted to investigate transcriptional differences. Differential gene expression analysis identified 3395 genes between the resistant and susceptible isolates and 3060 genes in the D-TN1-treated resistant isolate (FDR < 0.05, |log₂FC| ≥ 1). D-TN1 treatment in the resistant isolate was associated with downregulation of ribosomal and metabolic pathways. If confirmed with further in vivo studies, this new antimicrobial peptide may become a new therapeutic alternative in the treatment of trichomoniasis in the future. Full article

Background: Bacterial vaginosis and vaginal dysbiosis represent major causes of morbidity among women in sub-Saharan Africa, yet data from Madagascar remain scarce. This study aimed to assess the prevalence and determinants of vaginal bacterial infections among women in northern Madagascar and to explore how vaginal microflora composition reflects broader aspects of reproductive health. Methods: A cross-sectional study was conducted in April 2024 among 159 women (15–80 years) attending a rural second-referral clinic in Manerinerina, Ambatoboeny District. Sociodemographic and hygiene data were obtained through structured questionnaires. Vaginal pH was measured in situ, and Gram-stained smears were evaluated using the Nugent scoring system. The presence of Trichomonas vaginalis, Neisseria gonorrhoeae, and Candida spp. was assessed microscopically. Associations were analyzed using Chi-square or Fisher’s exact tests, with p < 0.05 considered significant. Results: Abnormal vaginal flora was observed in 68.6% of women, including 43.4% with BV (Nugent 7–10) and 25.2% with intermediate flora. Elevated vaginal pH correlated strongly with higher Nugent scores (p < 0.01). T. vaginalis and N. gonorrhoeae were detected in 10.7% and 9.4% of women, respectively, and both were significantly associated with dysbiosis (p = 0.02 and p = 0.04). Poor hygiene practices, vaginal douching (79.1% vs. 64.5%; p = 0.04), and unsafe water sources (p = 0.04) were major behavioral and environmental determinants. Conclusions: Vaginal dysbiosis is highly prevalent among women in northern Madagascar and closely linked to modifiable hygiene behaviors and environmental conditions. In resource-limited settings, Gram-stained microscopy and Nugent scoring remain cost-effective tools for surveillance and patient care. Culturally adapted education, improved water access, and integration of low-cost diagnostics are essential for reducing the burden of vaginal infections in rural Madagascar. Full article

Trichomoniasis is the most prevalent non-viral sexually transmitted infection worldwide and is caused by Trichomonas vaginalis. The development of resistance against the standard treatment, metronidazole, highlights the need for alternative therapeutic approaches. The role of innate immune cells is crucial for understanding trichomoniasis; however, the contribution of monocytes remains poorly characterized. We previously reported that the antimicrobial peptides LL-37 and its derivative KR-20 are trichomonacidal. In other systems, LL-37 displays immunomodulatory effects. Nevertheless, whether these peptides modulate monocyte responses in the presence of T. vaginalis remains unknown, which was the aim of this study. U937 monocytes were co-incubated with LL-37 or KR-20 (3 h), with or without parasite. Monocyte metabolic activity, nitric oxide production, and relative expression of innate immune genes were assessed. LL-37 decreased monocyte metabolic activity and upregulated TNF-α expression (10 and 5 μM, respectively) in parasite-challenged monocytes. Meanwhile, KR-20 (2.5–10 μM) preserved metabolic activity, bound microbial components (LPS), reduced parasite-induced nitric oxide production, and downregulated the expression of IL-8, TNF-α, IL-1β, and COX-2 in infected monocytes. This work provides initial evidence that KR-20 modulates innate immune response in monocytes during T. vaginalis infection, suggesting its potential—yet to be fully validated—as an immunomodulatory candidate for trichomoniasis. Full article

Background: Infections caused by the protozoan Trichomonas vaginalis affect millions of people worldwide and are responsible for one of the most common sexually transmitted diseases. Despite the efficacy of 5-nitroimidazoles like metronidazole, concerns regarding widespread resistance and the absence of viable alternatives for specific patient populations necessitate the development of structurally diverse pharmacological agents. In this study, we investigated the antiparasitic activity of 1,3-thiazolidin-4-one derivatives against T. vaginalis. Methods: Thiazolidines were synthesized via multicomponent reaction (MCR) using one-pot methodology and tested in vitro against the parasite and mammalian cell lines. Results: Seventy percent of the compounds showed more than 80% antiparasitic activity at 100 μM, with compounds 4a, 4b, and 4f exhibiting IC₅₀ ≤ 20 µM. None of the molecules exhibited cytotoxic against Vero CCL-81 and HeLa cells. Evaluation of the structure–activity relationship (SAR) indicates that the substituent at the nitrogen position of the heterocycle may be involved in the antiparasitic effect of these compounds. In silico studies also revealed that the three compounds possess adequate oral bioavailability and do not present mutagenic, tumorigenic or irritating risks. Finally, molecular docking predicted strong interactions of compounds 4a, 4b, and 4f with T. vaginalis enzymes lactate dehydrogenase and purine nucleoside phosphorylase; compound 4f also interacted with methionine Ƴ-lyase. Conclusions: These preliminary results suggest that 1,3-thiazolidin-4-ones are promising scaffolds for developing new trichomonacidal agents. Full article

Co-infection by human papillomavirus (HPV) and human immunodeficiency virus (HIV) facilitates cervical carcinogenesis, and additional cofactors such as other sexually transmitted infections (STI) further aggravate this scenario. This study aimed to validate a molecular detection strategy for Chlamydia trachomatis, Trichomonas vaginalis and Neisseria gonorrhoeae and to assess the association of these infections with cervical lesions in HPV-positive women living with HIV in Northeastern Brazil. In total, 155 samples were collected from CRIST/AIDS. After microorganism detection by conventional PCR, a multiplex PCR was standardized and validated. A prevalence of 9.03% was observed for C. trachomatis and 6.45% for T. vaginalis, with 0.64% co-infection. In addition, infection with both STIs showed a prevalence of 0.64%. Among HPV-positive women, high-risk genotypes accounted for 70.9% of cases, with HPV-16 being the most prevalent (35.5%). Overall, 18.2% of women presented cervical lesions, and 13.2% of those with co-detection of C. trachomatis and T. vaginalis were associated with high-grade squamous intraepithelial lesions (HSIL). These findings highlight the clinical relevance of screening for multiple STIs in HPV-positive women living with HIV and support the incorporation of multiplex molecular testing into public health strategies to improve early detection and targeted management. Full article

Trichomoniasis is the most common non-viral sexually transmitted infection in humans, with over 200 million people affected each year. This disease is associated with pre-term birth, low birth weight, and premature membrane rupture. Its causal pathogen, Trichomonas vaginalis (TV), is a prevalent sexually transmitted protozoan parasite that infects the urogenital tract through cytoadherence. TV infection alters TV gene expression and induces host immune responses, while TV-secreted exosomes carry RNA and protein cargoes that mediate extracellular signaling. This review summarizes recent discoveries of molecules that interact with host receptors involved in cytoadherence. We also discuss human innate and adaptive immune responses to TV infection via a variety of inflammatory mediators. Recent research on concurrent or endosymbiont relationships of TV with other urogenital microbes and cancers, is also examined. These studies not only highlight the necessity of understanding host–microbe interactions in TV pathogenesis but also provide a crucial insight into potential therapeutic targets of nitroimidazole-resistant TV strains. Full article

Background/Objectives: Transvaginal ultrasound is one of the basic diagnostic methods used during gynecological examination. Lack of care during such an examination can lead to a risk of dangerous infection for both the patient and medical staff. Therefore, a crucial part of the preparation for the test is its proper disinfection. The aim of this study was to test the effectiveness of ultraviolet (UV-C) disinfection of ultrasound probes used in transvaginal examination for the prevention of infections in patients and healthcare personnel in ambulatory care settings. Methods: The eradication of microorganisms present (as a microbiota or etiological factors of infections) in the female reproductive tract was tested. They were the following: Staphylococcus aureus, Staphylococcus haemolyticus, Streptococcus agalactiae, Klebsiella pneumoniae, Escherichia coli, Acinetobacter baumannii, Pseudomonas aeruginosa, Candida albicans, and Trichomonas vaginalis. The study consisted of contaminating the ultrasound transducer with microbial strains of known density, then performing disinfection and assessing the number of surviving microbial cells. Results: Almost complete eradication of all tested pathogenic microorganisms was achieved, except T. vaginalis. But for this protozoa eradication of mobile forms reaches around 80%. Conclusions: Although the sample size in our study was limited and statistical significance was not reached, the substantial logarithmic reduction strongly indicates the effectiveness of this method. Full article

Background: Placental infections caused by Schistosoma spp. and sexually transmitted microorganisms can adversely impact pregnancy outcomes. However, the association between molecular detection of these pathogens in placental tissue and corresponding histopathological inflammation remains unclear, particularly in sub-Saharan African populations. Methods: In this cross-sectional study, placental parenchyma specimens with limited membrane sampling were collected from 103 Ivorian and Ghanaian mothers without known pregnancy or birth complications. Tissue pieces adjacent to PCR-tested samples were analyzed by real-time PCR targeting Chlamydia trachomatis, Mycoplasma hominis, Neisseria gonorrhoeae, Schistosoma spp., Streptococcus agalactiae, Trichomonas vaginalis, Ureaplasma parvum and Ureaplasma urealyticum. Corresponding adjacent tissues were examined by routine histopathology, supplemented with immunohistochemistry when higher pathogen DNA quantities were detected, to assess inflammatory changes. Results: Real-time PCR detected U. urealyticum in 15 out of 103 cases (14.6%, ±0.7%), U. parvum in 13 (12.6%, ±0.6%), S. agalactiae in 11 (10.7%, ±0.5%), the S. haematobium complex in four (3.9%, ±0.2%), M. hominis in four (3.9%, ±0.2%), confirmed N. gonorrhoeae in two (1.9%, ±0.1%) and non-confirmed N. gonorrhoeae in one (1.0%, ±0.1%), T. vaginalis in two (1.9%, ±0.1%), and C. trachomatis (non-lymphogranuloma venereum serovar) in one (1.0%, ±0.1%). Overall, pathogen DNA levels were low, with only four positive PCR results yielding cycle threshold (Ct) values below 30 and none below 25. Histopathological examination revealed no relevant inflammatory changes in any samples. Conclusions: Placental parenchyma tissues with limited membrane sampling testing positive for Schistosoma spp. or sexually transmitted pathogens by molecular methods demonstrated no corresponding histopathological inflammation. These findings warrant confirmatory studies to better characterize potential region-specific placental infection phenotypes and their clinical significance. Full article

Background: Trichomonas vaginalis is the causative agent of human trichomoniasis, the most common non-viral sexually transmitted infection. This disease is associated with an increased susceptibility to HIV and HPV infections. Currently, resistance to metronidazole (MTZ), the main drug used for treatment, has been reported in up to 9.6% of cases; additionally, the compound is also associated with adverse side effects. Therefore, it is urgent to identify new treatment options. Objective: In this study, we investigated for the first time the in vitro and in silico activity against T. vaginalis of betulin and stigmasterol isolated from Tagetes nelsonii Greenm, as well as their hemolytic activity. Methods: Plant specimen was collected in Chiapas, Mexico. Hexane and methanol extracts were prepared through sonication-assisted maceration. The antiprotozoal and hemolytic activities were evaluated in vitro against Trichomonas vaginalis trophozoites and human erythrocytes. The most active extract was fractionated using chromatographic techniques in a bioassay-guided study. The active metabolites were identified by ¹H and ¹³C-NMR spectroscopy, and their biological activity was further assessed in silico against lactate dehydrogenase (LDH), pyruvate ferredoxin oxidoreductase (PFOR) methionine gamma-lyase (MGL) and purine nucleoside phosphorylase (PNP) T. vaginalis enzymes. Results: Both triterpenes showed anti-trichomonal activity and no hemolytic activity at 100 µg/mL. Molecular docking studies predicted promising interactions of triterpenes with T. vaginalis drug target proteins, TvpFOR and TvLDH. Conclusions: Our results revealed that betulin and stigmasterol are potential molecules for the development of new trichomonacidal therapies against T. vaginalis. Full article