molecular typing of T. vaginalis and M. hominis in Austria

Trichomonas vaginalis is the causative agent of trichomonosis, the worldwide most common non-viral sexually transmitted infection accounting for more cases than syphilis and gonorrhoea together. Symptoms include vaginal itching, pain when urinating and foul-smelling discharge. Chronic infections with T. vaginalis have been associated with enhanced recruitment of HIV, preterm delivery, infertility and cancer. More than 50% of all infections in women and mostly all infections in men remain asymptomatic. A symbiosis between T. vaginalis and Mycoplasma hominis, a sexually transmitted facultative pathogenic bacterium, has been described in up to 94% of clinical isolates of T. vaginalis. It has been shown that M. hominis impacts pathogenicity and possibly also the drug resistance of T. vaginalis. For Austria, no data concerning the frequency of infections with this symbiosis or the molecular background of the pathogens are available. It is known, that two genetic types of T. vaginalis differ in their virulence and metronidazole resistance. Furthermore, infections with the symbiosis show different and perhaps worse outcome, than infections with T. vaginalis alone. Thus, the data obtained in this study will be of considerable medical relevance. This study will be in collaboration with the Outpatients` Centre for Infectious Venero-Dermatological Diseases in Vienna, where patients are routinely screened for infections with T. vaginalis and also M. hominis. The main aim of this study is to obtain molecular epidemiological data for T. vaginalis and M. hominis, for Austrian isolates of these pathogens for the first time. With this typing it is aimed to screen for relatedness between T. vaginalis isolates (and M. hominis) in symbiosis compared to those without symbiont. Furthermore the prevalence of a virus (Trichomonas vaginalis virus; TVV) potentially living in T. vaginalis will be investigated to reveal a correlation between its presence and the ability to undergo symbiosis. Moreover, the prevalence data on infections with T. vaginalis as well as M. hominis in Austria will be updated, which were last investigated 20 years ago. Beyond that, all obtained isolates of T. vaginalis will be screened for the presence of M. hominis, thus evaluating the prevalence of this symbiosis in Austria for the first time. Tetracycline resistance and metronidazole tolearance of M. hominis and T. vaginalis respectively will also be analysed for the first time in Austrian isolates. Molecular typing will be achieved by DNA sequence analysis; the presence of TVV will be screened by gel-electrophoresis. Prevalence of symbiosis will be investigated using quantitative PCR (qPCR), as well as cultural methods. Tetracycline resistance of M. hominis will be tested using PCR to amplify a resistance mediating transposon. Metronidazole resistance of T. vaginalis will be analysed using cultural methods and a minimal inhibitory concentration assay. All results will be published in peer- reviewed international scientific journals.

We characterised 82 T. vaginalis (TV) isolates and detected the presence of the endosymbionts, M. hominis and TVV. M. hominis was detected in in 37% of the TV-positive patients; M. hominis DNA was found in 28% of the TVs. In 15% of the patients, M. hominis was detected in the clinical samples as well as within the respective TV isolates. In 22% of the patients, M. hominis was detected by culture only, thus most likely being extracellular of TV. In 11 patients, M. hominis was detected only within the respective cultured TV isolates (13%), while the urethral/vaginal swab samples were negative for M. hominis, implying that these M. hominis were exclusively intracellular and could be released upon therapy of TV. We detected the presence of TVV in 35% of tested samples. Our results provided a first insight into the distribution of symbionts in TV isolates from Austrian patients. The prevalence of genital Mycoplasmas and coinfection with TV in fresh isolates from female patients in Vienna was investigated. Mycoplasma species were detected in 28.2% of the collected vaginal samples. Mycoplasma hominis was found in 21.5% of the specimens, Ureaplasma species were found in 7.5% of the samples. The molecular data of the newly described species, Candidatus Mycoplasma girerdii, were obtained for the first time in Austria, in a sample also positive for TV. 654 leftovers of urine samples from healthy, asymptomatic Austrian soldiers were investigated for the prevalence of TV, Chlamydia trachomatis, and genital mycoplasmas by specific PCRs. Our study delivered data on STIs of a mainly male cohort, which are scarce because most of the available information on sexually transmitted infectious agents arises from fertility clinics (mainly women) or symptomatic patients.TV isolates were examined to calculate phylogenetic trees to determine whether the TV isolates we collected in Vienna are naturally related to each other and whether those that naturally carry M. hominis are more closely related to each other, which would allow us to reveal possible preconditions for symbiosis. Screening of two different genes has already been performed, data are now analysed. We investigated the presence of alr, goiB, and goiC genes in two groups of M. hominis isolates (group A: patient with M. hominis only; group B: patients with M. hominis and Ureaplasma spp.; in both groups no other STD was detected) collected from symptomatic and asymptomatic male and non-pregnant female patients attending the Outpatients Centre. We confirmed the presence of the alr gene in 85% of group A isolates and in 100% of group B isolates; goiB was detected in 46% of the samples in both groups, whereas goiC was found in 73% of group A and 79% of group B isolates, respectively.