A New Multiplex Genetic Detection Assay Method for the Rapid Semi-Quantitative Detection of Six Common Curable Sexually Transmitted Pathogens From the Genital Tract

Investigation of mycoplasma and ureaplasma species using a molecular method in male patients suffering from urethritis symptoms: a cross-sectional study in the city of Antalya

BACKGROUND

This study aimed to determine whether Mycoplasma (M) genitalium, M. hominis, Ureaplasma (U) urealyticum, and U. parvum were present in male patients with symptoms of urethritis.

METHODS

First-void urine and genital discharge samples were collected from 94 men. The samples were examined for the presence of M. genitalium, M. hominis, U. urealyticum, and U. parvum using a multiplex polymerase chain reaction (PCR) method (BioGX Mycoplasma-Ureaplasma-OSR commercial multiplex PCR kit, BioGX, the Netherlands). The presence of Trichomonas vaginalis and Neisseria (N) gonorrhoeae was investigated using microscopy and culture methods. In the M. genitalium-positive samples, macrolide resistance was evaluated using the Macrolide-R/MG ELITe MGB Kit (ELITechGroup S.p.A., Italy) on the ELITe BeGenius system.

RESULTS

A total of 55 microorganisms were detected in 41.5% of the patients (n = 39; U. urealyticum [n = 18], U. parvum [n = 14], N. gonorrhoeae [n = 9], M. hominis [n = 8], and M. genitalium [n = 6]). The positivity rates of M. genitalium and N. gonorrhoeae were statistically higher in the patients with more than 3 partners in the last 12 months, and those of U. urealyticum and N. gonorrhoeae were higher in the patients with genital discharge (p < 0.05). In addition, a significant relationship was found between N. gonorrhoeae positivity and genital itching and pain/discomfort during sexual intercourse (p < 0.05). Macrolide resistance was detected in 2 (33.3%) of the 6 M. genitalium-positive samples.

CONCLUSION

In this study, U. urealyticum, N. gonorrhoeae, and M. genitalium were detected in 19.1%, 9.6%, and 6.4% of the male patients who presented with symptoms of urethritis, respectively.

Prevalence of Chlamydia trachomatis, Neisseria gonorrhoeae, and Ureaplasma urealyticum infections in males and females of childbearing age in Chengdu, China

Background

Sexually transmitted infections (STIs) are a global public health issue, due to their high prevalence and potential impact on pregnancy outcome and fetal health. The objective of this study is to investigate the prevalence of STI-causative pathogens including Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Ureaplasma urealyticum (UU) as well as the epidemiological characteristics of STIs among males and females of childbearing age in Chengdu.

Methods

This retrospective cross-sectional study involved 15,055 participants of childbearing age including 7,235 males and 7,820 females. All specimens of participants were tested for CT, NG, and UU by nucleic acid amplification tests (NAATs) methods.

Results

27.80% of the participants were infected with at least one of the three pathogens, with significantly higher overall prevalence in females (45.22%) than males (8.98%, p<0.001). Multivariate logistic regression analysis demonstrated that gender was independently associated with both CT positivity (females vs males, OR 2.276, 95% CI 1.724-3.005, p<0.001) and UU positivity (females vs males, OR 8.079, 95% CI 7.183-9.086, p<0.001). Single infections predominated in both males and females (males: 98.15%; females: 93.16%), while mixed infections were more frequent in females (6.84%) than in males (1.85%). CT prevalence was highest in both males and females aged 18-24, followed by aged 25-30 and 31-35. Among aged 18-24, the prevalence of UU in males and NG and UU in females were also higher. Compared to other age groups, mixed infections (CT+NG, CT+UU, NG+UU, CT+NG+UU) were also highest in females aged 18-24. Compared to other clinical diagnostic groups, The prevalence of CT, NG and mixed infection of CT+NG was highest in both males and females in the urogenital inflammation group (p<0.05).

Conclusions

Among the population of childbearing age in Chengdu, China, the prevalence among females was significantly higher than that among males. Single infections predominated in both males and females, while mixed infections occurred more frequently in females. STIs were more prevalent in sexually active young people aged 18-35, especially in the 18-24 age group. CT and NG infections in both males and females may cause urogenital inflammation, and mixed infections of CT+NG further elevate the risk of inflammatory responses.

A simple and colorimetric method utilizing cell-free toehold switch sensors for the detection of Chlamydia trachomatis, Ureaplasma urealyticum and Neisseria gonorrhoeae

BACKGROUND

Sexually transmitted infections (STIs) rank among the most prevalent acute infectious conditions and remain a major global public health concern. Notable STI pathogens include Chlamydia trachomatis (CT), Ureaplasma urealyticum (UU), and Neisseria gonorrhoeae (NG). Early detection and diagnosis are crucial for controlling the spread of STIs.

RESULTS

In this study, we utilized toehold switches integrated with a cell-free system to develop a simple, colorimetric, sensitive, specific and rapid method for the parallel detection of CT, UU, and NG. Target DNA and sensor DNA were transcribed into target trigger RNA and toehold switch sensor RNA respectively, within a cell-free transcription system. The binding of target RNA to the toehold switch RNA activated the switch, subsequently initiating the translation of the downstream lacZ gene. The expressed LacZ protein hydrolyzed the substrate chlorophenol red-β-d-galactopyranoside (CPRG), resulting in a color change from yellow to purple, which provided a visible colorimetric output. The three screened sensors exhibited excellent orthogonality without any observed cross-reactivity. By enhancing sensitivity with recombinase polymerase amplification (RPA), we reliably detected NG in clinical samples using this method, with no interference from other pathogens. Moreover, we selected high-performance toehold switch sensor for paper-based detection, further enhancing portability.

SIGNIFICANCE

In summary, this technique enables the simple snd sensitive parallel detection of CT, UU, and NG, generating visible colorimetric results without the need for specialized personnel or sophisticated equipment. Given these advantages, this method holds significant potential as a simple and portable diagnostic tool in resource-limited settings or point-of-care testing (POCT) scenarios.

Low-cost conventional PCR techniques enable simultaneous detection of bacterial sexually transmitted infections with enhanced sensitivity and specificity

PURPOSE

Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT) and Mycoplasma hominis (MH), the three most common treatable bacterial sexually transmitted infections (STIs) worldwide can lead to many complications if remain untreated. Screening of high-risk population with highly sensitive methods will lead to significant improvement in patient outcomes and will prevent downward transmission. The advantages of Polymerase chain reaction (PCR) based assay are not only high sensitivity and specificity, but also detection of multiple organisms in a single reaction which reduce the result turn-around time. The aim of the present study was to evaluate the feasibility of a multiplex PCR assay method targeting 16S rRNA gene for simultaneous detection of NG, CT and MH infection along with their trend and occurrence among high-risk population in Assam, Northeast India.

METHODS

A cross-sectional study was undertaken, where a total of 200 randomly selected patients from high-risk population were included. After validation of singleplex PCR, Multiplex PCR (M-PCR) was performed along with the traditional culture method for NG.

RESULTS & CONCLUSION

The overall agreement of M-PCR with singleplex PCR was very high (100%). The occurrence of STI was found to be very high (101/200; 50.5%). Furthermore, co-infection was detected in 10/200; 5%) individuals. Infection was more common among young individuals (p < 0.05) and males out-numbered females (p < 0.05). The most common organism detected was CT (42/200; 21%) followed by NG (41/200; 20.5%) and MH (20/200; 10%). The M-PCR assay workflow is simple, cost effective and can be used in routine diagnostic laboratories with basic molecular facilities.

Clinical characteristics of the host DNA-removed metagenomic next-generation sequencing technology for detecting SARS-CoV-2, revealing host local immune signaling and assisting genomic epidemiology

BACKGROUND

Metagenomic next-generation sequencing (mNGS) technology has been central in detecting infectious diseases and helping to simultaneously reveal the complex interplay between invaders and their hosts immune response characteristics. However, it needs to be rigorously assessed for clinical utility. The present study is the first to evaluate the clinical characteristics of the host DNA-removed mNGS technology for detecting SARS-CoV-2, revealing host local immune signaling and assisting genomic epidemiology.

METHODS

46 swab specimens collected from COVID-19 patients were assayed by two approved commercial RT-qPCR kits and mNGS. The evolutionary tree of SARS-CoV-2 was plotted using FigTree directly from one sample. The workflow of removing the host and retaining the host was compared to investigate the influence of host DNA removal on the performances of mNGS. Functional enrichment analysis of DEGs and xCell score were used to explore the characteristics of host local immune signaling.

RESULTS

The detection rate of mNGS achieved 92.9% (26/28) for 28 samples with a Ct value ≤ 35 and 81.1% (30/37) for all 46 samples. The genome coverage of SARS-CoV-2 could reach up to 98.9% when the Ct value is about 20 in swab samples. Removing the host could enhance the sensitivity of mNGS for detecting SARS-CoV-2 from the swab sample but does not affect the species abundance of microbes RNA. Improving the sequencing depth did not show a positive effect on improving the detection sensitivity of SARS-CoV-2. Cell type enrichment scores found multiple immune cell types were differentially expressed between patients with high and low viral load.

CONCLUSIONS

The host DNA-removed mNGS has great potential utility and superior performance on comprehensive identification of SARS-CoV-2 and rapid traceability, revealing the microbiome's transcriptional profiles and host immune responses.

Rapid and simultaneous detection of multiple pathogens in the lower reproductive tract during pregnancy based on loop-mediated isothermal amplification-microfluidic chip

Background

Female reproductive tract infection (RTI) is the common source of varied diseases, especially as an important risk factor for pregnancy outcomes, therefore the rapid, accurate and simultaneous detection of multiple pathogens is in urgent need for assisting the diagnosis and treatment of RTI in pregnant women. Streptococcus agalactiae (S. agalactiae), Enterococcus faecalis (E. faecalis), Gardnerella vaginalis (G. vaginalis), Candida albicans (C. albicans) and Chlamydia trachomatis (C. trachomatis) are five main pathogens in lower genital tract with high risk, serious consequences and clinical demands. The combination of loop-mediated isothermal amplification (LAMP) and microfluidic technology was used to develop the LAMP-microfluidic chip for rapid, simple, sensitive and simultaneous detection of the five target pathogens above.

Results

Standard strains and clinical isolates were used for the establishment of the novel LAMP method in tube and LAMP-microfluidic chip, followed by the chip detection on 103 clinical samples and PCR verification partially. The sensitivities of LAMP of S. agalactiae, E. faecalis, G. vaginalis, and C. albicans in tube were 22.0, 76.0, 13.2, 1.11 CFU/μL, respectively, and C. trachomatis was 41.3 copies/μL; on LAMP-microfluidic chip they were 260, 154, 3.9 and 7.53 CFU/μL, respectively, and C. trachomatis was 120 copies/μL. The positive coincidence rates of clinical stains in tube and on chip experiments were 100%. Compared with the classic culture method performed in hospitals, the positive coincidence rate of the 103 clinical samples detected by LAMP-microfluidic chip were 100%. For the six inconsistent ones, including four G. vaginalis and two C. albicans positive samples tested by LAMP-microfluidic chip and verified by PCR were negative by culturing method in hospitals, indicating the lack of efficient detection by the classic culturing method.

Conclusion

Our study suggested that the LAMP-microfluidic chips could simultaneously, efficiently, and accurately detect multiple main pathogens, including S. agalactiae, E. faecalis, G. vaginalis, C. albicans and C. trachomatis, in clinical samples of female RTI to give a great clinical value. Accordingly, this novel method has the potential to provide a valuable reference for female RTI screening and early diagnosis during pregnancy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12866-022-02657-0.

Detection of Ureaplasma urealyticum by Catalytic Hairpin Assembly Combined with a Lateral Flow Immunoassay Strip

Ureaplasma urealyticum is a common genital mycoplasma in men and women, which can cause reproductive tract infection and infertility, and is also related to adverse pregnancy outcomes and neonatal diseases. Pathogen culture and polymerase chain reaction (PCR) are the main methods for the diagnosis of U. urealyticum. However, pathogen culture takes too long, and PCR requires professional personnel and sophisticated instruments. Here, we report a simple, convenient, sensitive, and specific detection method, which combines catalytic hairpin assembly with a lateral flow immunoassay strip. Only a water bath and a fluorescence reader are needed to detect the results in 30 min. We can realize the point-of-care testing of U. urealyticum by this method. To verify this method, we selected 10 clinical samples for testing, and the test results were exactly the same as the clinical report.

Copan Walk Away Specimen Processor (WASP) Automated System for Pathogen Detection in Female Reproductive Tract Specimens

Objective

Automation is increasingly being applied in clinical laboratories; however, preanalytical processing for microbiology tests and screening is still largely performed using manual methods owing to the complex procedures involved. To promote automation of clinical microbiology laboratories, it is important to assess the performance of automated systems for different specimen types separately. Therefore, the aim of this study was to explore the potential clinical application of the Copan Walk Away Specimen Processor (WASP) automated preanalytical microbiology processing system in the detection of pathogens in female reproductive tract specimens and its feasibility in optimizing diagnostic procedures.

Methods

Female reproductive tract specimens collected from pregnant women at their first obstetric check-up were inoculated into culture media using the Copan WASP automated specimen processing system and were also cultured using a conventional manual inoculation method. After 48 h of culture, the growth of colonies was observed, and the types of bacteria, number of colonies, and efficiency in isolating single colonies were compared between the automated and manual groups. The specimens collected from the WASP system using the Copan-ESwab sample collection tubes were further analyzed for the presence of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and Ureaplasmaurealyticum (UU) via fluorescence quantitative polymerase chain reaction (qPCR) and an immunochromatographic assay to investigate the feasibility of this method in optimizing detection of these common pathogens of the female reproductive tract.

Results

Compared with the manual culture method, the Copan WASP microbiology automation system detected fewer bacterial types (P<0.001) and bacterial colonies (P<0.001) but had a higher detection rate of single colonies (P<0.001). There was no significant difference in the detection rates of common pathogens encountered in clinical obstetrics and gynecology, including group B Streptococcus (GBS) (P=0.575) and Candida (P=0.917), between the two methods. Specimens collected in the Copan-ESwab tubes could be used for screening of GBS and CT via fluorescence-based qPCR but not with immunochromatography. However, UU and NG were not detected in any sample with either method; thus, further validation is required to determine the feasibility of the Copan system for screening these pathogens.

Conclusion

The Copan WASP microbiology automation system could facilitate the optimization of diagnostic procedures for detecting common pathogens of the female reproductive system, thereby reducing associated costs.