METHODS: Urine and urethral swab samples were collected from the primary public sexual health clinic in Singapore and tested for C. trachomatis (CT) or N. gonorrhoeae (NG) infection and for the presence of M. genitalium. Antibiotic resistance in M. genitalium strains detected was determined by screening for genomic mutations associated with macrolide and fluroquinolone resistance.
RESULTS: We report the results of a study into M. genitalium prevalence at the national sexual health clinic in Singapore. M. genitalium was heavily associated with CT infection (8.1% of cases), but present in only of 2.4% in CT negative cases and not independently linked to NG infection. Furthermore, we found high rates of resistance mutations to both macrolides (25%) and fluoroquinolones (37.5%) with a majority of resistant strains being dual-resistant. Resistance mutations were only found in strains from patients with CT co-infection.
CONCLUSIONS: Our results support targeted screening of CT positive patients for M. genitalium as a cost-effective strategy to reduce the incidence of M. genitalium in the absence of comprehensive routine screening. The high rate of dual resistance also highlights the need to ensure the availability of alternative antibiotics for the treatment of multi-drug resistant M. genitalium isolates.
METHODOLOGY: Respiratory secretions were examined for chlamydiae by cell culture, enzyme-linked immunosorbent assay and polymerase chain reaction-enzyme immunoassay. Sera were tested by micro-immunofluorescence for chlamydial IgG, IgM and IgA. Other bacterial and viral pathogens were also looked for by standard cultural and serological methods.
RESULTS: Of 87 patients aged 2 months-3 years, an aetiologic diagnosis was made in 41 (47.1%). C. pneumoniae and C. trachomatis were each detected in 1 (1.2%) of the patients. Among common bacterial pathogens, Haemophilus influenzae (13.8%) and Streptococcus pneumoniae (8.1%) were the most frequently identified. Respiratory viruses and elevated Mycoplasma pneumoniae antibodies were found in 10.3% and 9.1% of patients, respectively.
CONCLUSION: Chlamydiae are infrequent causes of community-acquired acute lower respiratory tract infections in infants and very young children in Malaysia.
METHODS: A total of 19 patients with genital C. trachomatis infection and 10 age-matched healthy controls were recruited for the study. Peripheral blood mononuclear cells (PBMCs) isolated from genital C. trachomatis-infected females were cultured in the presence of CPAF, HSP60 and MOMP antigens, and cytokines were measured by ELISA assay.
RESULTS: We reported that pro-inflammatory cytokines (TNF-α, IL-1β and IL-6) were robustly secreted following antigenic exposure. Notably, CPAP and MOMP were more potent in triggering IL-1β, as compared to HSP60. Elevated levels of the proinflammatory cytokines were also noted in the samples infected with plasmid-bearing C. trachomatis as compared to those infected with plasmid-free strains.
CONCLUSIONS: Our study highlights distinct ability of chlamydial antigens in triggering pro-inflammatory response in the host immune cells.
METHODS: De-identified residual specimens from women aged 16-24 years submitted for chlamydia testing were collected from three pathology laboratories in Victoria and New South Wales. Limited demographic information, and chlamydia test results were also collected. Patient identifiers were sent directly from the laboratories to the National HPV Vaccination Program Register, to obtain HPV vaccination histories. Samples underwent HPV genotyping using Seegene Anyplex II HPV 28 assay.
RESULTS: Between April and July 2018, 362 residual samples were collected, the majority (60.2%) of which were cervical swabs. Demographic data and vaccination histories were received for 357 (98.6%) women (mean age 21.8, SD 2.0). Overall, 65.6% of women were fully vaccinated, 9.8% partially, and 24.7% unvaccinated. The majority (86.0%) resided in a major city, 35.9% were classified in the upper quintile of socioeconomic advantage and chlamydia positivity was 7.8%.The prevalence of quadrivalent vaccine-targeted types (HPV6/11/16/18) was 2.8% (1.5-5.1%) overall with no differences by vaccination status (p = 0.729). The prevalence of additional nonavalent vaccine-targeted types (HPV31/33/45/52/58) was 19.3% (15.6-23.8%). One or more oncogenic HPV types were detected in 46.8% (95% CI 41.6-52.0%) of women.
CONCLUSIONS: HPV testing of residual chlamydia specimens provides a simple, feasible method for monitoring circulating genotypes. Applied on a larger scale this method can be utilised to obtain a timely assessment of nonavalent vaccine impact among young women not yet eligible for cervical screening.
OBJECTIVES: The objective of this study was to determine the contribution of host metabolites in genital Ct infection.
METHODS: We used high-performance liquid chromatography-mass spectrometry, and mapped lipid profiles in genital swabs obtained from female guinea pigs at days 3, 9, 15, 30 and 65 post Ct serovar D intravaginal infection.
RESULTS: Across all time points assessed, 13 distinct lipid species including choline, ethanolamine and glycerol were detected. Amongst these metabolites, phosphatidylcholine (PC) was the predominant phospholipid detected from animals actively shedding bacteria i.e., at 3, 9, and 15 days post infection. However, at days 30 and 65 when the animals had cleared the infection, PC was observed to be decreased compared to previous time points. Mass spectrometry analyses of PC produced in guinea pigs (in vivo) and 104C1 guinea pig cell line (in vitro) revealed distinct PC species following Ct D infection. Amongst these, PC 16:0/18:1 was significantly upregulated following Ct D infection (p < 0.05, >twofold change) in vivo and in vitro infection models investigated in this report. Exogenous addition of PC 16:0/18:1 resulted in significant increase in Ct D in Hela 229 cells.
CONCLUSION: This study demonstrates a role for host metabolite, PC 16:0/18:1 in regulating genital Ct infection in vivo and in vitro.
OBJECTIVE: We aimed to identify the prevalence and risk factors of genitourinary C.trachomatis infection among patients attending STD clinics in northern Peninsular Malaysia.
METHODS: A hospital-based cross-sectional study was conducted in STD clinics of Hospital Pulau Pinang and Hospital Sultanah Bahiyah, Kedah from January to November 2014. Participants were individually interviewed using a structured data collection form followed by a physical examination and laboratory tests. Nucleic Acid Amplification Test (NAAT) was used to detect C.trachomatis infection. Analysis was carried out using SPSS Version 15.
RESULTS: Eighty-three sexually active patients were enrolled, consisting of 51 males and 32 females. The median age was 28.0 years. In general, 32.5% patients were asymptomatic, the remaining presented with genital discharge (41.0%), genital warty lesion (25.3%), genital ulcer (13.3%), dysuria (13.3%), dyspareunia (2.4%), urine hesistancy (1.2%) and genital swelling (1.2%). The prevalence of genitourinary C.trachomatis infection was 21.7% in the study population; 17.6% in males and 28.1% in females. Among the infected females, 44.4% were pregnant. Of those infected 56.6% did not show any symptoms of genital infection, and 77.8% were aged between 18 and 30 years, of which most were females. Among newly diagnosed HIV patients, the prevalence was 14.3%. From multivariable logistic regression analysis, age under 28 years, being married and engagement in oral sex had significantly increased odds of C.trachomatis infection.
CONCLUSIONS: C.trachomatis infection was common among patients attending STD clinics in northern Penisular Malaysia especially in the younger age groups. Majority of the infected patients were asymptomatic.