Moraxella catarrhalis associated with acute urethritis imitating gonorrhoea acquired by oral-genital contact

Emerging Presence of Culturable Microorganisms in Clinical Samples of the Genitourinary System: Systematic Review and Experience in Specialized Care of a Regional Hospital

The detection of emerging pathogens responsible for genitourinary infections has increased with technological advances. We conducted a systematic review of publications on the involvement of these microorganisms in genitourinary samples, and we also investigated their presence and antibiotic susceptibility in samples from patients at our regional hospital (Granada, Spain). The MEDLINE database was searched up to 31 December 2020, and a cross-sectional descriptive study was performed of results obtained in urine samples and genital exudates from January 2016 through December 2019. The review highlighted the frequent involvement of Neisseria meningitidis in genital infections, while the data on other microorganisms were consistent with findings in our patient series. The emerging microorganisms most often responsible for urinary tract infections were Streptococcus bovis (58.5%) and Gardnerella vaginalis (23.6%) in females, and S. bovis (32.3%), Aerococcus urinae (18.6%), and Corynebacterium spp. (16.9%) in males; those most frequently reported in genital infections were S. viridans (36.4%) in females and C. glucuronolyticum (32.2%) and G. vaginalis (35.6%) in males. In general, emerging pathogens are resistant to conventional antibiotics such as penicillin. However, there has also been an increase in beta-lactam resistance by the S. bovis group and Corynebacterium spp. The systematic review showed that emerging microorganisms are responsible for only a small percentage of genitourinary infections but are of major clinical interest, with a predominance of the S. bovis group, G. vaginalis, Lactobacillus spp., Aerococcus spp., and Corynebacterium spp. in urine samples and of G. vaginalis and C. glucuronolyticum in genital samples. Given the increasing resistance to antibiotics empirically prescribed in patients with genitourinary infections, it is recommended to create an antibiogram in all cases.

Signaling Role of Adipocyte Leptin in Prostate Cell Proliferation Induced by Trichomonas vaginalis

Leptin is a type of adipokine mainly produced by adipocytes and reported to be overproduced in prostate cancer. However, it is not known whether it stimulates the proliferation of prostate cells. In this study, we investigated whether benign prostatic hyperplasia epithelial cells (BPH-1 cells) infected with Trichomonas vaginalis induced the proliferation of prostate cells via a leptin signaling pathway. To investigate the effect of crosstalk between adipocyte leptin and inflamed epithelial cell in proliferation of prostate cells, adipocytes 3T3-L1 cells were incubated in conditioned medium of BPH-1 cells infected with T. vaginalis (T. vaginalis-conditioned medium, TCM), and then the adipocyte-conditioned medium (ATCM) was identified to cause proliferation of prostate cells. BPH-1 cells incubated with live T. vaginalis released pro-inflammatory cytokines, and conditioned medium of these cells caused migration of adipocytes. When prostate stromal cells and BPH-1 cells were incubated with adipocyte conditioned medium containing leptin, their growth rates increased as did expression of the leptin receptor (known as OBR) and signaling molecules such as JAK2/STAT3, Notch and survivin. Moreover, blocking the OBR reduced this proliferation and the expression of leptin signaling molecules in response to ATCM. In conclusion, our findings show that inflamed BPH-1 cells infected with T. vaginalis induce the proliferation of prostate cells through leptin-OBR signaling. Therefore, it is likely that T. vaginalis contributes to prostate enlargement in BPH via adipocyte leptin released as a result of inflammation of the prostate.

Proliferation of prostate epithelia induced by IL-6 from stroma reacted with Trichomonas vaginalis

Benign prostatic hyperplasia (BPH) is characterized by the proliferation of stromal and epithelial cell types in the prostate, and interactions between the two types of cells. We demonstrated previously that proliferation of prostate stromal cells was induced by BPH epithelial cells in response to Trichomonas vaginalis (Tv) infection via crosstalk with mast cells. In this study, we investigated whether IL-6 released by the proliferating stromal cells in turn induce the BPH epithelial cells to multiply. When culture supernatants of the proliferating prostate stromal cells were added to BPH epithelial cells, the latter multiplied, and expression of cyclin D1, FGF2 and Bcl-2 increased. Blocking the IL-6 signalling pathway with anti-IL-6R antibody or JAK1/2 inhibitor inhibited the proliferation of the BPH epithelial cells and reduced the expression of IL-6, IL-6R and STAT3. Also, epithelial-mesenchymal transition was detected in the proliferating BPH epithelial cells. In conclusion, IL-6 released from proliferating prostate stromal cells induced by BPH epithelial cells infected with Tv in turn induces multiplication of the BPH epithelial cells. This result provides first evidence that the inflammatory microenvironment of prostate stromal cells resulting from Tv infection induces the proliferation of prostate epithelial cells by stromal-epithelial interaction.

Corynebacterium propinquum associated with acute, nongonococcal urethritis

Corynebacterium propinquum is usually considered part of the normal human oropharyngeal flora and is rarely responsible for clinical infection. We report here what seems to be the first case of acute purulent urethral discharge in a young Iranian man with urethritis acquired after orogenital contact. Attention should be devoted to less common nondiphtheriae Corynebacterium species for differential diagnosis.

Characteristics of acute nongonococcal urethritis in men differ by sexual preference

Nongonococcal urethritis (NGU) is a common clinical syndrome, but no etiological agent is identified in a significant proportion of cases. Whether the spectrum of pathogens differs between heterosexual men (MSW) and men who have sex with men (MSM) is largely unstudied but of considerable clinical relevance. A retrospective review was done using the electronic medical record database of Melbourne Sexual Health Centre, Australia. Cases were first presentations of symptomatic acute NGU with ≥ 5 polymorphonuclear leukocytes (PMNL)/high-powered field (HPF) on urethral Gram stain between January 2006 and December 2011. First-stream urine was tested for Chlamydia trachomatis and Mycoplasma genitalium by PCR. Demographic, laboratory, and behavioral characteristics of cases were examined by univariate and multivariable analyses. Of 1,295 first presentations of acute NGU, 401 (32%; 95% confidence interval [CI] of 29 to 34%) had C. trachomatis and 134 (11%; 95% CI of 9 to 13%) had M. genitalium detected. MSM with acute NGU were less likely to have C. trachomatis (adjusted odds ratio [AOR] = 0.4; 95% CI of 0.3 to 0.6) or M. genitalium (AOR = 0.5; 95% CI of 0.3 to 0.8) and more likely to have idiopathic NGU (AOR = 2.4; 95% CI of 1.8 to 3.3), to report 100% condom use for anal/vaginal sex (AOR = 3.6; 95% CI of 2.7 to 5.0), or to have engaged in sexual activities other than anal/vaginal sex (AOR = 8.0; 95% CI of 3.6 to 17.8). Even when C. trachomatis or M. genitalium was detected, MSM were more likely than MSW to report consistent condom use (OR = 4.7; 95% CI of 2.6 to 8.3). MSM with acute NGU are less likely to have the established bacterial sexually transmitted infections (STIs) and more likely to report protected anal sex or sexual activity other than anal sex prior to symptom onset than MSW. These data suggest that the etiologic spectrum of pathogens differs between MSM and MSW in acute NGU and that relatively low-risk practices are capable of inducing acute NGU.

Moraxella catarrhalis: from interactions with the host immune system to vaccine development

Moraxella catarrhalis is a human-restricted commensal that over the last two decades has developed into an emerging respiratory tract pathogen. The bacterial species is equipped with various adhesins to facilitate its colonization. Successful evasion of the human immune system is a prerequisite for Moraxella infection. This strategy involves induction of an excessive proinflammatory response, intervention of granulocyte recruitment to the infection site, activation of selected pattern recognition receptors and cellular adhesion molecules to counteract the host bacteriolytic attack, as well as, finally, reprogramming of antigen presenting cells. Host immunomodulator molecules are also exploited by Moraxella to aid in resistance against complement killing and host bactericidal molecules. Thus, breaking the basis of Moraxella immune evasion mechanisms is fundamental for future invention of effective therapy in controlling Moraxella infection.