Aetiology and prevalence of mixed-infections and mono-infections in non-gonococcal urethritis in men: a case-control study

The Relationship Between Insertive Oral and Anal Sex and Select Measures of the Composition of the Urethral Microbiota Among Men Who Have Sex With Men

BACKGROUND

Sexual behavior may influence the composition of the male urethral microbiota, but this hypothesis has not been tested in longitudinal studies of men who have sex with men (MSM).

METHODS

From December 2014 to July 2018, we enrolled MSM with nongonococcal urethritis (NGU) attending a sexual health clinic. Men attended 5 in-clinic visits at 3-week intervals, collected weekly urine specimens at home, and reported daily antibiotics and sexual activity on weekly diaries. We applied broad-range 16S rRNA gene sequencing to urine. We used generalized estimating equations to estimate the association between urethral sexual exposures in the prior 7 days (insertive oral sex [IOS] only, condomless insertive anal intercourse [CIAI] only, IOS with CIAI [IOS + CIAI], or none) and Shannon index, number of species (observed, oral indicator, and rectal indicator), and specific taxa, adjusting for recent antibiotics, age, race/ethnicity, HIV, and preexposure prophylaxis.

RESULTS

Ninety-six of 108 MSM with NGU attended ≥1 follow-up visit. They contributed 1140 person-weeks of behavioral data and 1006 urine specimens. Compared with those with no urethral sexual exposures, those with IOS only had higher Shannon index ( P = 0.03 ) but similar number of species and presence of specific taxa considered, adjusting for confounders; the exception was an association with Haemophilus parainfluenzae . CIAI only was not associated with measured aspects of the urethral microbiota. IOS + CIAI was only associated with presence of H. parainfluenzae and Haemophilus .

CONCLUSIONS

Among MSM after NGU, IOS and CIAI did not seem to have a substantial influence on measured aspects of the composition of the urethral microbiota.

Characteristics of common pathogens of urogenital tract among outpatients in Shanghai, China from 2016 to 2021

Background

Ureaplasma urealyticum, Chlamydia trachomatis, and Neisseria gonorrhoeae are the prevalent causes of several genital diseases worldwide; however, their characteristics in different genders have not been well documented in Shanghai. The aim of this study is to describe the prevalence of common pathogens among outpatients, considering variations by gender and age.

Methods

From January 1, 2016, to December 31, 2021, the urogenital swabs of 16216 outpatients aged 3-95 years from two general hospitals in Shanghai were collected. All participants' swabs were investigated for U. urealyticum, C. trachomatis, and N. gonorrhoeae by isothermal RNA-based simultaneous amplification and testing. The basic information of all participants was also recorded, including age and gender. The chi-square test was used to compare the prevalence between different genders, age groups, and infection patterns.

Results

There were 5,744 patients (35.42%) with positive samples whose ages ranged from 7 to 80 years (33.23 ± 8.63 years), and 62.14% of them were women. The most common pathogen detected was U. urealyticum (85.08%). The highest prevalence rate of all three pathogens was found in patients aged ≤ 20 years (40.53%, 95% confidence intervals [CI]: 33.80%-47.63%). The prevalent rate of U. urealyticum was higher in men (33.36%, 95% CI: 32.19%-34.55%). The overall prevalence rates of U. urealyticum, C. trachomatis, and N. gonorrhoeae were 30.14% (95% CI: 29.44%-30.85%), 6.00% (95% CI: 5.64%-6.38%), and 2.10% (95% CI: 1.89%-2.33%).

Conclusions

Ureaplasma urealyticum was the most prevalent pathogen in the population, and its prevalence decreased with age. Young men aged ≤ 20 years were more frequently infected. Regular screening for sexually transmitted pathogens in different genders and age groups are warranted, particularly in young men.

Chlamydia trachomatis-An Emerging Old Entity?

Chlamydia trachomatis is an evasive pathogen that can prompt severe clinical manifestations in humans such as vaginitis, epididymitis, lymphogranuloma venereum, trachoma, conjunctivitis and pneumonia. If left untreated, chronic infections with C. trachomatis can give rise to long-lasting and even permanent sequelae. To shed some light on its widespread nature, data from original research, systematic reviews and meta-analyses from three databases was collected and analyzed in the context of chlamydial infection, related symptoms and appropriate treatment modalities. This review describes the bacterium's pervasiveness on a global scale, especially in developing countries, and suggests ways to halt its transmission and spread. Infections with C. trachomatis often go unnoticed, as many individuals are asymptomatic and unaware of their diagnosis, contributing to a delay in diagnosis and treatment. The high prevalence of chlamydial infection highlights the need for a universal screening and detection method enabling immediate treatment at its onset. Prognosis is favorable with antibiotic therapy and education for high-risk groups and their sexual partners. In the future, a quick, easily accessible, and inexpensive test should be developed to diagnose and treat infected individuals early on. Along with a vaccine against C. trachomatis, it would halt the transmission and spread of the pathogen worldwide.

Sexual behavior shapes male genitourinary microbiome composition

The origin, composition, and significance of the distal male urethral microbiome are unclear, but vaginal microbiome dysbiosis is linked to new sex partners and several urogynecological syndromes. We characterized 110 urethral specimens from men without urethral symptoms, infections, or inflammation using shotgun metagenomics. Most urethral specimens contain characteristic lactic acid bacteria and Corynebacterium spp. In contrast, several bacteria associated with vaginal dysbiosis were present only in specimens from men who reported vaginal intercourse. Sexual behavior, but not other evaluated behavioral, demographic, or clinical variables, strongly associated with inter-specimen variance in urethral microbiome composition. Thus, the male urethra supports a simple core microbiome that is established independent of sexual exposures but can be re-shaped by vaginal sex. Overall, the results suggest that urogenital microbiology and sexual behavior are inexorably intertwined, and show that the male urethra harbors female urogenital pathobionts.

The Urethral Microbiota of Men with and without Idiopathic Urethritis

Nongonococcal urethritis (NGU) is a common genital tract syndrome in men, and up to 50% of cases are considered idiopathic, i.e., no etiological agent is identified. This poses challenges for clinicians in the diagnosis and treatment of NGU and often results in antibiotic misuse and overuse. Therefore, to identify potential infectious causes of urethritis and inform clinical management of urethritis cases, we characterized and compared the urethral microbiota of men with and without idiopathic urethritis. Participants were derived from a case-control study that examined viral and bacterial pathogens and sexual practices associated with NGU. Men with NGU who tested negative for established causes of NGU (Chlamydia trachomatis, Mycoplasma genitalium, Trichomonas vaginalis, adenoviruses, herpes simplex virus [HSV]-1, and/or HSV-2) were classified as idiopathic cases, and the controls were men reporting no current urethral symptoms. Men provided a urine sample that was used to characterize the urethral microbiota using 16S rRNA gene sequencing. Bacterial taxa associated with idiopathic urethritis were identified using analysis of compositions of microbiomes with bias correction. When stratified by sex of sexual partner, we found that the abundance of Haemophilus influenzae was significantly increased in men who have sex with men with idiopathic urethritis, and the abundance of Corynebacterium was significantly increased in men who have sex with women with idiopathic urethritis. Other taxa, including Ureaplasma, Staphylococcus haemolyticus, Streptococcus pyogenes, Escherichia, and Streptococcus pneumoniae/pseudopneumoniae, dominated the urethral microbiota of idiopathic urethritis cases but not controls, suggesting that these organisms may also contribute to urethritis. Importantly, the taxa we identified represent biologically plausible causes of urethritis and should be prioritized for future study.

Sexually transmitted pathogens causing urethritis: A mini-review and proposal of a clinically based diagnostic and therapeutic algorithm

The purpose of this mini-review was to provide the latest information and concepts on diagnosis and treatment of the most common sexually transmitted pathogens causing urethritis. The incidence of several sexually transmitted infections that cause urethritis is increasing, and this genitourinary syndrome is among the most common reason young men see clinical care. The authors performed a literature search including the currently valid guidelines, and an overview of the most relevant pathogens is given. Moreover, the authors developed a clinically applicable diagnostic and therapeutic algorithm, because early diagnosis and correct treatment can sometimes prevent infected individuals from significant morbidity. Future research will focus on new methods to combat pathogens that cause urethritis, including vaccination.

Evaluation of Clinical, Gram Stain, and Microbiological Cure Outcomes in Men Receiving Azithromycin for Acute Nongonococcal Urethritis: Discordant Cures Are Associated With Mycoplasma genitalium Infection

BACKGROUND

In men with nongonococcal urethritis (NGU), clinicians and patients rely on clinical cure to guide the need for additional testing/treatment and when to resume sex, respectively; however, discordant clinical and microbiological cure outcomes do occur. How accurately clinical cure reflects microbiological cure in specific sexually transmitted infections (STIs) is unclear.

METHODS

Men with NGU were tested for Neisseria gonorrhoeae, Chlamydia trachomatis (CT), Mycoplasma genitalium (MG), Trichomonas vaginalis, urethrotropic Neisseria meningitidis ST-11 clade strains, and Ureaplasma urealyticum (UU). Men received azithromycin 1 g and returned for a 1-month test-of-cure visit. In MG infections, we evaluated for the presence of macrolide resistance-mediating mutations (MRMs) and investigated alternate hypotheses for microbiological treatment failure using in situ shotgun metagenomic sequencing, phylogenetic analysis, multilocus sequence typing analyses, and quantitative PCR.

RESULTS

Of 280 men with NGU, 121 were included in this analysis. In the monoinfection group, 52 had CT, 16 had MG, 7 had UU, 10 had mixed infection, and 36 men had idiopathic NGU. Clinical cure rates were 85% for CT, 100% for UU, 50% for MG, and 67% for idiopathic NGU. Clinical cure accurately predicted microbiological cure for all STIs, except MG. Discordant results were significantly associated with MG-NGU and predominantly reflected microbiological failure in men with clinical cure. Mycoplasma genitalium MRMs, but not MG load or strain, were strongly associated with microbiological failure.

CONCLUSIONS

In azithromycin-treated NGU, clinical cure predicts microbiological cure for all STIs, except MG. Nongonococcal urethritis management should include MG testing and confirmation of microbiological cure in azithromycin-treated MG-NGU when MRM testing is unavailable.

Are Urogenital Symptoms Caused by Sexually Transmitted Infections and Colonizing Bacteria?

OBJECTIVE

This study aimed to investigate the prevalence of sexually transmitted infections (STIs) and colonizing bacteria in relation to urogenital symptoms.

MATERIALS AND METHODS

In this cross-sectional study, patients visiting the STI clinic at Umeå University Hospital were asked for symptoms and condom use. Samples from 759 patients (465 male and 294 female) were analyzed for 4 STIs (Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, and Mycoplasma genitalium) and 3 colonizing bacteria (Mycoplasma hominis, Ureaplasma parvum, and Ureaplasma urealyticum).

RESULTS

Chlamydia trachomatis prevalence was 11% among women and 9.5% among men. Neisseria gonorrhoeae prevalence was 0.7% among women and 0.9% among men. Mycoplasma genitalium was found in 11% and 5.6% of women and men, respectively. Asymptomatic men and women had similar distribution patterns of microorganisms as those with urogenital symptoms, with the exceptions of Neisseria gonorrhoeae- and Mycoplasma genitalium-infected men who declared symptoms more frequently. Of 158 men with urogenital symptoms, 55% were test-negative. Of 129 women with urogenital symptoms, 12% were test-negative.

CONCLUSIONS

This study reveals a complex picture, where a large number of multi-positive tests made it complicated to correlate urogenital symptoms with microorganisms. A high number of test-negative but symptomatic patients indicate a need of searching for additional pathogens.

Clinical profile and co-infections of urethritis in males

BACKGROUND

Infectious urethritis are classified in N. gonorrhoeae (NG) urethritis and non-gonococcal urethritis, caused commonly by C. trachomatis (CT) or M. genitalium (MG) in Western Europe. The primary objective of the study is to evaluate the association between the clinical profile and the pathogens. Secondly, to assess the prevalence of co-infections.

METHODS

The clinical profile of urethritis in men caused by NG, CT and MG confirmed by nucleic acid amplification test (NAAT) on first void urine has been retrospectively collected. The clinical profiles comprised the assessment of dysuria and/or discharge and the clinical-dermoscopic examination of the genitalia. Serological tests for syphilis and HIV were also performed.

RESULTS

A total of 101 episodes of NAAT confirmed NG, CT or MG urethritis were identified. The prevalence for each pathogen was 50.60%, 33.73% and 15.66%, respectively. Co-infections were observed in few cases (four MG+CT, one NG+CT, one NG+MG), with M. hominis, U. urealitycum and U. parvum positivity found concomitantly in 7-8% cases. The median age of patients was 33 years. Dysuria was reported in 88% cases (95% NG, 79% CT, 78% MG urethritis). Urethral discharge was found in 86% of cases, including purulent discharge in 61% (98% NG, 70% MG) and transparent in 25% (64% CT). Dysuria and purulent discharge were observed in 95% NG, 54% MG and 29% CT cases, whereas dysuria and transparent discharge were observed in 50% CT, 23% MG and in none of NG cases (P<0.01). Balanitis/meatitis was observed in 24% of cases, genital warts in 12% and proctalgia in 4%.

CONCLUSIONS

NAAT is crucial for defining urethritis etiology. Dysuria is the most common symptom. Gonococcal urethritis present with purulent discharge, whereas transparent discharge is associated with non-gonococcal pathogens. Co-infections are rare. Clinical exam may detect other infectious diseases, in particular genital warts.

The effect of screening and treatment of Ureaplasma urealyticum infection on semen parameters in asymptomatic leukocytospermia: a case-control study

Background

Ureaplasma urealyticum (UU) infection, as well as asymptomatic leukocytospermia, whether it has effect on semen parameters and whether it needs screening and treatment is still a confusing and controversial topic for clinicians.

Methods

Among 1530 adult males who visited Guilin People's Hospital due to infertility, 295 were diagnosed with asymptomatic leukocytospermia, and 95 were further screened for UU-positive. 81 UU-positive asymptomatic leukocytospermia patients received 7-day or 14-day treatment plan with doxycycline, and 70 cases were cured. The semen parameters of non-leukocytospermia, leukocytospermia, UU-positive leukocytospermia and UU-negative leukocytospermia groups were compared, and the differences between the two treatment plans and the semen parameters before UU treatment and 1 month after UU-cured were compared.

Results

Compared with non-leukocytospermia patients, the sperm concentration, progressive motility (PR), and normal morphology of patients with leukocytospermia decreased, while those with UU-positive leukocytospermia performed more significantly. The PR, total motility, and normal morphology of UU-positive leukocytospermia patients were significantly lower than those of UU-negative leukocytospermia patients (all p < 0.001). The UU cure rates of the 7-day and 14-day treatment plan with doxycycline was 84.62% and 89.66% (p = 0.738), respectively, and the sperm concentration, PR, total motility, and normal morphology of the cured UU-positive leukocytospermia patients were all increased after 1 month (p = 0.001, p = 0.022, p = 0.004 and p = 0.008, respectively).

Conclusions

It is significant to screen and treat UU infection in asymptomatic leukocytospermia for improving sperm quality. Where appropriate, the 7-day treatment plan with doxycycline may be a good choice.

Urethral Microbiota in Men: Association of Haemophilus influenzae and Mycoplasma penetrans With Nongonococcal Urethritis

BACKGROUND

Nongonococcal urethritis (NGU) is a common syndrome with no known etiology in ≤50% of cases. We estimated associations between urethral bacteria and NGU in men who have sex with men (MSM) and men who have sex with women (MSW).

METHODS

Urine was collected from NGU cases (129 MSM, 121 MSW) and controls (70 MSM, 114 MSW) attending a Seattle STD clinic. Cases had ≥5 polymorphonuclear leukocytes on Gram stain plus symptoms or discharge; controls had <5 PMNs, no symptoms, no discharge. NGU was considered idiopathic when Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, Trichomonas vaginalis, adenovirus, and herpes simplex virus were absent. The urethral microbiota was characterized using 16S rRNA gene sequencing. Compositional lasso analysis was conducted to identify associations between bacterial taxa and NGU and to select bacteria for targeted qPCR.

RESULTS

Among NGU cases, 45.2% were idiopathic. Based on compositional lasso analysis, we selected Haemophilus influenzae (HI) and Mycoplasma penetrans (MP) for targeted qPCR. Compared with 182 men without NGU, the 249 men with NGU were more likely to have HI (14% vs 2%) and MP (21% vs 1%) (both P ≤ .001). In stratified analyses, detection of HI was associated with NGU among MSM (12% vs 3%, P = .036) and MSW (17% vs 1%, P < .001), but MP was associated with NGU only among MSM (13% vs 1%, P = .004). Associations were stronger in men with idiopathic NGU.

CONCLUSIONS

HI and MP are potential causes of male urethritis. MP was more often detected among MSM than MSW with urethritis.

Development of a SimpleProbe real-Time PCR Assay for rapid detection and identification of the US novel urethrotropic clade of Neisseria meningitidis ST-11 (US_NmUC)

Urethritis, or inflammation of the urethra, is one of the most common reasons men seek clinical care. Sexually transmitted pathogens including Neisseria gonorrhoeae are responsible for over half of the symptomatic urethritis cases in U.S. men. Recently, clinics in Indianapolis, Columbus, Atlanta, and other U.S. cities began to note increasing numbers of men presenting with urethritis and Gram-negative intracellular diplococci in their urethral smears who test negative for N. gonorrhoeae. Many of these discordant cases, which have periodically reached highs of more than 25% of presumed gonococcal cases in some sexually transmitted infection clinics in the U.S. Midwest, are infected with strains in a novel urethrotropic clade of Neisseria meningitidis ST-11 (US_NmUC). However, no cultivation-independent tests are available for the US_NmUC strains, and prior studies relied on microbial culture and genome sequencing to identify them. Here, we describe a PCR test that can identify the US_NmUC strains and distinguish them from commensal and invasive N. meningitidis strains as well as N. gonorrhoeae. Our SimpleProbe®-based real-time PCR assay targets a conserved nucleotide substitution in a horizontally acquired region of US_NmUC strain genomes. We applied the assay to 241 urine specimens whose microbial compositions had previously been determined by deep shotgun metagenomic sequencing. The assay detected the single US_NmUC positive case in this cohort, with no false positives. Overall, our simple and readily adaptable assay could facilitate investigation of the pathogenesis and epidemiology of the US_NmUC clade.