Molecular methods for the detection of Mycoplasma and ureaplasma infections in humans: a paper from the 2011 William Beaumont Hospital Symposium on molecular pathology

An Update in Antimicrobial Therapies and Infection Prevention in Pediatric Lung Transplant Recipients

Lung transplantation can offer life-prolonging therapy to children with otherwise terminal end-stage lung disease. However, infectious complications, like those experienced by their adult counterparts, are a significant cause of morbidity and mortality. These include bacteria, viruses, and fungi that infect the patient pretransplant and those that may be acquired from the donor or by the recipient in the months to years posttransplant. An understanding of the approach to the management of each potential infecting organism is required to ensure optimal outcomes. In particular, emphasis on aggressive preoperative management of infections in pediatric patients with cystic fibrosis is important. These include multidrug-resistant Gram-negative bacteria, fungi, and Mycobacterium abscessus, the posttransplant outcome of which depends on optimal pretransplant management, including vaccination and other preventive, antibiotic-sparing strategies. Similarly, increasing the transplant donor pool to meet rising transplant demands is an issue of critical importance. Expanded-criteria donors-those at increased risk of blood-borne viruses in particular-are increasingly being considered and transplants undertaken to meet the rising demand. There is growing evidence in the adult pool that these transplants are safe and associated with comparable outcomes. Pediatric transplanters are therefore likely to be presented with increased-risk donors for their patients. Finally, numerous novel antibiotic-sparing therapeutic approaches are on the horizon to help combat infections that currently compromise transplant outcomes.

Vaginal Ureaplasma species increase chorioamnionitis in very preterm infants with preterm premature rupture of the membranes at < 28 weeks of gestation

Our aim was to investigate the association between vaginal Ureaplasma species (spp.) and the subsequent occurrence of chorioamnionitis (CAM), perinatal death, neonatal morbidity, and long-term neurodevelopmental impairments (NDIs) at 3 years of age. We analyzed 55 pregnant women with singleton pregnancy who had preterm premature rupture of the membranes (pPROM) at < 28⁺⁰ weeks of gestation, and delivered between 22⁺⁰ and 31⁺⁶ weeks at our tertiary hospital in 2007-2016. NDIs were defined as either cerebral palsy or developmental delay evaluated at 1.5 and/or 3 years old. The presence of Ureaplasma spp. and Mycoplasma hominis were evaluated using urea-arginine broth and Mycoplasma PPLO Agar. The presence of Ureaplasma spp. in the vagina was positive in 41%. Vaginal Ureaplasma spp. was a significant risk factor for CAM; however, it was not significantly associated with the occurrence of perinatal death, pulmonary hypoplasia, respiratory distress syndrome, transient tachypnea of the newborn, intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia defined as oxygen required and occasional ventilatory assistance required at week 36 as modified (BPD₃₆), or NDIs. The crude odds ratio (95% confidence interval) of Ureaplasma spp. for the occurrence of CAM was 9.5 (1.10-82) (p = 0.041). In very preterm birth infants with pPROM, CAM, BPD₃₆, and NDIs occurred in 78, 60, and 36%, respectively. Vaginal Ureaplasma spp. was a significant risk factor for CAM in very preterm birth infants with pPROM. The incidences of BPD₃₆ and NDIs in such infants were very high, nearing 3/5 and 1/3, respectively.

Evaluation of the Virclia® automated chemiluminescent immunoassay system for diagnosing pneumonia caused by Mycoplasma pneumoniae

BACKGROUND

Mycoplasma pneumoniae is considered an important etiologic agent of community-acquired pneumonia (CAP) in outpatients. We aimed to evaluate the diagnostic accuracy of a quick automated chemiluminescent immunoassay (CLIA) for M. pneumoniae in a population-based prospective study of CAP.

METHODS

A total of 137 outpatients diagnosed with CAP were included in the study. Acute- and convalescent phase sera were analyzed for IgG and IgM to M. pneumoniae with both CLIA (VirClia^® ) and ELISA immunoassays. Conventional serological criteria by quantitative ELISA were considered as reference standard. Sensitivity and specificity of the assay were assessed with the construction of receiver operating characteristic (ROC) curves, and the kappa index was used to evaluate the accuracy of the IgG and IgM determinations in the acute phase.

RESULTS

Thirty-eight patients were diagnosed with pneumonia by M. pneumoniae. ROC curves for IgG and IgM of convalescent and acute phase (C/A) quotients by the CLIA and ELISA assays were comparable. Specifically, for the CLIA, the best C/A quotient for IgG was 2.617 (sensitivity, 94.9%; specificity, 99.9%), and for IgM 1.400 (sensitivity, 65.8%; specificity, 100%). Regarding the acute phase, the best diagnostic accuracy for the CLIA was obtained with an IgG index of 1.120 (sensitivity, 89.5%; specificity, 73.7%). The CLIA was very simple to execute and required a minimum sample handling.

CONCLUSION

The accuracy of the Virclia^® assay for the diagnosis of M. pneumoniae infection in outpatients with CAP was equivalent to the quantitative ELISA. The CLIA was quicker to perform and displayed better analytic workability than conventional ELISA.

Evaluation of a real-time PCR assay for detection of Mycoplasma genitalium and macrolide resistance-mediating mutations from clinical specimens

Mycoplasma genitalium (MG) is a sexually transmitted pathogen for which there is no FDA-approved diagnostic test available in the United States. A modified real-time polymerase chain reaction assay for detecting MG and simultaneously identifying macrolide resistance mutations from clinical specimens was evaluated and proved to be sensitive and accurate for diagnostic purposes.

Primary Peritonitis: An Index Case of Mycoplasma hominis Infection in a Healthy Female

Introduction

Primary peritonitis in healthy immunocompetent individuals is rare. Several case reports of Streptococcus species causing peritonitis have been described. Here, we present the first case of Mycoplasma hominis as the cause of primary peritonitis in a healthy woman.

Case Report

A 42-year-old female with history of uterine fibroids was admitted with abdominal pain and intraperitoneal fluid of unknown etiology. She was initially managed nonoperatively and empirically treated with broad spectrum antibiotics. Blood and urine cultures were unrevealing. Increasing abdominal pain and peritoneal fluid prompted diagnostic laparoscopy which revealed a dense fibrinous exudate covering the entire peritoneal cavity. Peritoneal fluid and biopsies were sent for cytology and culture. The peritoneal fluid was eventually sent for 16 s ribosomal analysis, which discovered Mycoplasma hominis RNA. Her antibiotics were narrowed, and she eventually made a full recovery.

Discussion

M. hominis is a rare source of systemic infection but has been known to colonize the urogenital tract and cause localized infections. This is the first presentation of M. hominis causing primary peritonitis in a healthy immunocompetent female. Multidisciplinary management of these patients is critical to achieve a timely diagnosis. Surgical exploration is often unavoidable to rule out secondary peritonitis.

A Systematic Review of Mycoplasma and Ureaplasma in Urogynaecology

Mycoplasma species relevant to the urogenital tract include mycoplasma hominis, mycoplasma genitalia and ureaplasma urealyticum. Their occurrence in the context of urogynaecological disease has been demonstrated in urethritis, cystitis and upper renal tract infections. Their role in hyperactive bladder and interstitial cystitis/painful bladder syndrome is controversial. All the above-mentioned microorganisms can occur as commensals or as potential pathogens. In most cases their role in any particular pathology cannot be proven, only presumed. The aim of this systematic review was to summarise current knowledge on the influence of mycoplasma and ureaplasma in urogynaecological pathology and to provide clinical guidance on diagnosis (when and how is pathogen detection indicated?) and treatment. 377 relevant articles were analysed. In summary: a urethral swab for PCR analysis of the three bacteria should be performed in the context of symptomatic sterile leukocyturia, chronic urethritis and suspected hyperactive bladder or interstitial cystitis/painful bladder syndrome. Symptomatic women should be treated strictly according to results of the antibiogram.

Rapid and simple detection of Ureaplasma species from vaginal swab samples using a loop-mediated isothermal amplification method

PROBLEM

Ureaplasma species occasionally cause chorioamnionitis and premature labor. We developed a novel assay employing a loop-mediated isothermal amplification (LAMP) method to detect Ureaplasma parvum and Ureaplasma urealyticum.

METHOD OF STUDY

Loop-mediated isothermal amplification primers were designed to amplify Ureaplasma-specific ureaseB genes. Four U. parvum strains, 5 U. urealyticum strains and 14 reference bacterial species were evaluated. Forty-six vaginal swab samples were analyzed by LAMP, culture, and PCR.

RESULTS

Our LAMP primers were specific to each species and had no cross-reaction. Of 46 clinical specimens, the sensitivity, specificity, and positive and negative predictive values of the LAMP method were 100% (12/12), 100% (34/34), 100% (12/12), and 100% (34/34), respectively, whereas those of PCR were 66.7% (8/12), 100% (34/34), 100% (8/8), and 89.5% (34/38), respectively, compared to culture-based detection.

CONCLUSION

The LAMP detection method outperformed the culture and PCR methods. Early detection enables appropriate antibiotic selection for improved prenatal outcomes.

Mycoplasma pneumoniae from the Respiratory Tract and Beyond

Mycoplasma pneumoniae is an important cause of respiratory tract infections in children as well as adults that can range in severity from mild to life-threatening. Over the past several years there has been much new information published concerning infections caused by this organism. New molecular-based tests for M. pneumoniae detection are now commercially available in the United States, and advances in molecular typing systems have enhanced understanding of the epidemiology of infections. More strains have had their entire genome sequences published, providing additional insights into pathogenic mechanisms. Clinically significant acquired macrolide resistance has emerged worldwide and is now complicating treatment. In vitro susceptibility testing methods have been standardized, and several new drugs that may be effective against this organism are undergoing development. This review focuses on the many new developments that have occurred over the past several years that enhance our understanding of this microbe, which is among the smallest bacterial pathogens but one of great clinical importance.

Mycoplasma hominis and Mycoplasma genitalium in the Vaginal Microbiota and Persistent High-Risk Human Papillomavirus Infection

Background

Recent studies have suggested that the vaginal microenvironment plays a role in persistence of high-risk human papillomavirus (hrHPV) infection and thus cervical carcinogenesis. Furthermore, it has been shown that some mycoplasmas are efficient methylators and may facilitate carcinogenesis through methylation of hrHPV and cervical somatic cells. We examined associations between prevalence and persistence of Mycoplasma spp. in the vaginal microbiota, and prevalent as well as persistent hrHPV infections.

Methods

We examined 194 Nigerian women who were tested for hrHPV infection using SPF₂₅/LiPA₁₀ and we identified Mycoplasma genitalium and Mycoplasma hominis in their vaginal microbiota established by sequencing the V3–V4 hypervariable regions of the 16S rRNA gene. We defined the prevalence of M. genitalium, M. hominis, and hrHPV based on positive result of baseline tests, while persistence was defined as positive results from two consecutive tests. We used exact logistic regression models to estimate associations between Mycoplasma spp. and hrHPV infections.

Results

The mean (SD) age of the study participants was 38 (8) years, 71% were HIV positive, 30% M. genitalium positive, 45% M. hominis positive, and 40% hrHPV positive at baseline. At follow-up, 16% of the women remained positive for M. genitalium, 30% for M. hominis, and 31% for hrHPV. There was a significant association between persistent M. hominis and persistent hrHPV (OR 8.78, 95% CI 1.49–51.6, p 0.01). Women who were positive for HIV and had persistent M. hominis had threefold increase in the odds of having persistent hrHPV infection (OR 3.28, 95% CI 1.31–8.74, p 0.008), compared to women who were negative for both.

Conclusion

We found significant association between persistent M. hominis in the vaginal microbiota and persistent hrHPV in this study, but we could not rule out reverse causation. Our findings need to be replicated in larger, longitudinal studies and if confirmed, could have important diagnostic and therapeutic implications.

Genital Mycoplasma infection among Mexican women with systemic lupus erythematosus

OBJECTIVE

To assess the prevalence of genital Mycoplasma spp. among women with systemic lupus erythematosus (SLE) and to identify factors associated with such infection.

METHODS

A cross-sectional study was conducted among patients with SLE and healthy women who attended a hospital in Puebla, Mexico, between July 29, 2014, and January 4, 2015. All participants were aged 18 years or older and sexually active. A structured interview assessed sociodemographic, obstetric, gynecologic, and clinical characteristics. Disease activity was evaluated using the Mexican SLE Disease Activity Index. Polymerase chain reaction was used to detect the presence of Mycoplasma spp. in genital samples.

RESULTS

Ureaplasma urealyticum was the only genital mycoplasma detected; it was present in 32 (24.6%) of 130 patients with SLE and 12 (12.8%) of 94 healthy women. Patients with SLE had increased odds of infection (odds ratio 2.120, 95% confidence interval 1.046-4.296). Among patients with SLE, multiparity was more common in those with U. urealyticum infection (P=0.043).

CONCLUSION

One-quarter of women with SLE had genital infection with U. urealyticum. An association was found between infection and multiparity among women with SLE.

Multi-center evaluation of one commercial and 12 in-house real-time PCR assays for detection of Mycoplasma pneumoniae

Detection of Mycoplasma pneumoniae by real-time PCR is not yet standardized across laboratories. We have implemented a standardization protocol to compare the performance of thirteen commercial and in-house approaches. Despite differences on threshold values of samples, all assays were able to detect at least 20M. pneumoniae genomes per reaction.

Neonatal CNS infection and inflammation caused by Ureaplasma species: rare or relevant?

Colonization with Ureaplasma species has been associated with adverse pregnancy outcome, and perinatal transmission has been implicated in the development of bronchopulmonary dysplasia in preterm neonates. Little is known about Ureaplasma-mediated infection and inflammation of the CNS in neonates. Controversy remains concerning its incidence and implication in the pathogenesis of neonatal brain injury. In vivo and in vitro data are limited. Despite improving care options for extremely immature preterm infants, relevant complications remain. Systematic knowledge of ureaplasmal infection may be of great benefit. This review aims to summarize pathogenic mechanisms, clinical data and diagnostic pitfalls. Studies in preterm and term neonates are critically discussed with regard to their limitations. Clinical questions concerning therapy or prophylaxis are posed. We conclude that ureaplasmas may be true pathogens, especially in preterm neonates, and may cause CNS inflammation in a complex interplay of host susceptibility, serovar pathogenicity and gestational age-dependent CNS vulnerability.

How recent advances in molecular tests could impact the diagnosis of pneumonia

Molecular diagnostic tests have been the single major development in pneumonia diagnostics over recent years. Nucleic acid detection tests (NATs) have greatly improved the ability to detect respiratory viruses and bacterial pathogens that do not normally colonize the respiratory tract. In contrast, NATs do not yet have an established role for diagnosing pneumonia caused by bacteria that commonly colonize the nasopharynx due to difficulties discriminating between pathogens and coincidental carriage strains. New approaches are needed to distinguish infection from colonization, such as through use of quantitative methods and identification of discriminating cut-off levels. The recent realization that the lung microbiome exists has provided new insights into the pathogenesis of pneumonia involving the interaction between multiple microorganisms. New developments in molecular diagnostics must account for this new paradigm.

Diagnostic methods to determine microbiology of postpartum endometritis in South Asia: laboratory methods protocol used in the Postpartum Sepsis Study: a prospective cohort study

Background

The South Asian region has the second highest risk of maternal death in the world. To prevent maternal deaths due to sepsis and to decrease the maternal mortality ratio as per the World Health Organization Millenium Development Goals, a better understanding of the etiology of endometritis and related sepsis is required. We describe microbiological laboratory methods used in the maternal Postpartum Sepsis Study, which was conducted in Bangladesh and Pakistan, two populous countries in South Asia.

Methods/Design

Postpartum maternal fever in the community was evaluated by a physician and blood and urine were collected for routine analysis and culture. If endometritis was suspected, an endometrial brush sample was collected in the hospital for aerobic and anaerobic culture and molecular detection of bacterial etiologic agents (previously identified and/or plausible).

Discussion

The results emanating from this study will provide microbiologic evidence of the etiology and susceptibility pattern of agents recovered from patients with postpartum fever in South Asia, data critical for the development of evidence-based algorithms for management of postpartum fever in the region.

Intra-uterine experimental infection by Ureaplasma diversum induces TNF-α mediated womb inflammation in mice

Ureaplasma diversum is an opportunistic pathogen associated with uterine inflammation, impaired embryo implantation, infertility, abortions, premature birth of calves and neonatal pneumonia in cattle. It has been suggested that the intra-uterine infection by Ureaplasma diversum can cause vascular changes that hinder the success of pregnancy. Thus, the aim of this study was to evaluate the changes of intrauterine site of A/J mice in estrus or proestrus phase inoculated with Ureaplasma diversum. The infection was monitored at 24, 48 and 72 hours by the PCR methodology to detect the Ureaplasma in the inoculation site and the profile of circulating blood cells. Morphological changes, intensity of inflammation and the production of cytokines were compared. The infected mice showed local inflammation through the production of IFN-γ and TNF-α. Ureaplasma diversum infections in the reproductive tract of studied mice seemed to be associated with the production of pro-inflammatory cytokines in uterine parenchyma. The levels of TNF-α of infected mice were dependent on the bacterial load of inoculated Ureaplasma. Uterine experimental infections by Ureaplasma diversum have not been mentioned yet and herein we presented the first report of an intrauterine infection model in mice.

Molecular Detection of Ureaplasma urealyticum from Prostate Tissues using PCR-RFLP, Tehran, Iran

BACKGROUND

In most cases, prostatitis can be caused by a bacterial agent such as Ureaplasma urealyticum. Considering to the cumbersome of the culture method for the detection of Ureaplasma species in clinical samples such as prostate; PCR method that is faster and more appropriate than the cultivation methods, can be utilized for the detection of U. urealyticum and U. parvum. PCR-RFLP method can differentiate both biovars and assist in studies of the clinical diagnosis, epidemiology and pathology of this species in human. The aim of this study was to molecular detection of U. urealyticumin in prostate tissue samples based on PCR- RFLP.

METHODS

Two hundred prostate tissue samples were collected from patient suffering from prostatitis. The PCR assay was used to amplify a 559 bp fragment of 16S-23SRNA interspace region of Ureaplasma. After sequencing, PCR products from positive samples were digested with TaqI restriction enzyme.

RESULTS

Seven cases (3.5%) out of 200 prostate tissue samples were positive for U. urealyticum. Results of PCR products sequencing demonstrated that all isolates were U. parvum biovar. PCR-RFLP results shown that there was not any differentiation in pattern of enzymatic digestion, in addition, all isolates were U. parvum, serovar 3.

DISCUSSION

U. urealyticum can be one of the causing agents of prostatitis. Using PCR-RFLP with specific primer and restriction enzyme is a rapid and cost-effect method for detection and differentiation of Ureaplasma from clinical samples.

Ureaplasma: current perspectives

Ureaplasma species are the most prevalent genital Mycoplasma isolated from the urogenital tract of both men and women. Ureaplasma has 14 known serotypes and is divided into two biovars- Ureaplasma parvum and Ureaplasma urealyticum. The organism has several genes coding for surface proteins, the most important being the gene encoding the Multiple Banded Antigen (MBA). The C-terminal domain of MBA is antigenic and elicits a host antibody response. Other virulence factors include phospholipases A and C, IgA protease and urease. Besides genital tract infections and infertility, Ureaplasma is also associated with adverse pregnancy outcomes and diseases in the newborn (chronic lung disease and retinopathy of prematurity). Infection produces cytokines in the amniotic fluid which initiates preterm labour. They have also been reported from renal stone and suppurative arthritis. Genital infections have also been reported with an increasing frequency in HIV-infected patients. Ureaplasma may be a candidate 'co factor' in the pathogenesis of AIDS. Culture and polymerase chain reaction (PCR) are the mainstay of diagnosis. Commercial assays are available with improved turnaround time. Micro broth dilution is routinely used to test antimicrobial susceptibility of isolates. The organisms are tested against azithromycin, josamycin, ofloxacin and doxycycline. Resistance to macrolides, tetracyclines and fluoroquinolones have been reported. The susceptibility pattern also varies among the biovars with biovar 2 maintaining higher sensitivity rates. Prompt diagnosis and initiation of appropriate antibiotic therapy is essential to prevent long term complications of Ureaplasma infections. After surveying PubMed literature using the terms 'Ureaplasma', 'Ureaplasma urealyticum' and 'Ureaplasma parvum', relevant literature were selected to provide a concise review on the recent developments.

Role of Ureaplasma Respiratory Tract Colonization in Bronchopulmonary Dysplasia Pathogenesis: Current Concepts and Update

Respiratory tract colonization with the genital mycoplasma species Ureaplasma parvum and Ureaplasma urealyticum in preterm infants is a significant risk factor for bronchopulmonary dysplasia (BPD). Recent studies of the ureaplasmal genome, animal infection models, and human infants have provided a better understanding of specific virulence factors, pathogen-host interactions, and variability in genetic susceptibility that contribute to chronic infection, inflammation, and altered lung development. This review provides an update on the current evidence supporting a causal role of ureaplasma infection in BPD pathogenesis. The current status of antibiotic trials to prevent BPD in Ureaplasma-infected preterm infants is also reviewed.

Detection of feline upper respiratory tract disease pathogens using a commercially available real-time PCR test

Feline herpesvirus (FHV-1), feline calicivirus (FCV), Bordetella bronchiseptica (Bb), Chlamydia felis (Cf) and Mycoplasma felis (Mf) are common infectious agents identified in cats with upper respiratory tract disease (URTD). Each of these agents can either act as primary pathogens or cause subclinical infections, and pathogen identification can be used to prevent disease transmission in shelters, or to manage individual cats with recurrent URTD. The aim of this study was to compare pathogen detection rates using real-time PCR testing and virus isolation (VI) or bacterial culture in conjunctival, nasal and oropharyngeal swabs from 18 shelter-housed cats with clinical URTD. Co-infections were common; FHV-1 was most prevalent and Cf and FCV were least prevalent. Agents detected by PCR were FCV 2/18 (11%), FHV-1 17/18 (94%), Bb 8/18 (44%) and Mf 15/18 (83%). Agents detected by VI and bacterial culture were FCV 1/18 (6%), FHV-1 12/18 (67%), Bb 8/18 (44%) and Mf 12/18 (67%). Agreement between PCR results and the other two methods was: FHV-1, 57.4%; FCV, 98.1%; Bb, 75.0%; Mf, 60.0%. Discordancies included PCR-positive, VI-negative (FCV, n = 1/54, 1.9%; FHV-1, n = 23/54, 42.6%), PCR-positive, culture-negative (Bb, n = 6/36, 16.7%; Mf, n = 13/36, 36.1%) or PCR-negative, culture-positive (Bb, n = 3/36, 8.3%; Mf, n = 2/36, 5.6%) results. A combination of an oropharyngeal swab and either a conjunctival or a nasal swab submitted for PCR testing was able to detect all infectious agents tested for in each cat. PCR testing was a sensitive and convenient method of detection of infectious agents in cats with clinical signs of URTD.

Antibiotic Susceptibility and Sequence Type Distribution of Ureaplasma Species Isolated from Genital Samples in Switzerland

Antibiotic resistance in Ureaplasma urealyticum/Ureaplasma parvum and Mycoplasma hominis is an issue of increasing importance. However, data regarding the susceptibility and, more importantly, the clonality of these organisms are limited. We analyzed 140 genital samples obtained in Bern, Switzerland, in 2014. Identification and antimicrobial susceptibility tests were performed by using the Mycoplasma IST 2 kit and sequencing of 16S rRNA genes. MICs for ciprofloxacin and azithromycin were obtained in broth microdilution assays. Clonality was analyzed with PCR-based subtyping and multilocus sequence typing (MLST), whereas quinolone resistance and macrolide resistance were studied by sequencing gyrA, gyrB, parC, and parE genes, as well as 23S rRNA genes and genes encoding L4/L22 ribosomal proteins. A total of 103 samples were confirmed as positive for U. urealyticum/U. parvum, whereas 21 were positive for both U. urealyticum/U. parvum and M. hominis. According to the IST 2 kit, the rates of nonsusceptibility were highest for ciprofloxacin (19.4%) and ofloxacin (9.7%), whereas low rates were observed for clarithromycin (4.9%), erythromycin (1.9%), and azithromycin (1%). However, inconsistent results between microdilution and IST 2 kit assays were recorded. Various sequence types (STs) observed previously in China (ST1, ST2, ST4, ST9, ST22, and ST47), as well as eight novel lineages, were detected. Only some quinolone-resistant isolates had amino acid substitutions in ParC (Ser83Leu in U. parvum of serovar 6) and ParE (Val417Thr in U. parvum of serovar 1 and the novel Thr417Val substitution in U. urealyticum). Isolates with mutations in 23S rRNA or substitutions in L4/L22 were not detected. This is the first study analyzing the susceptibility of U. urealyticum/U. parvum isolates in Switzerland and the clonality outside China. Resistance rates were low compared to those in other countries. We hypothesize that some hyperepidemic STs spread worldwide via sexual intercourse. Large combined microbiological and clinical studies should address this important issue.

Loop-mediated isothermal amplification (LAMP) for the rapid detection of Mycoplasma genitalium

Mycoplasma genitalium is a sexually transmissible, pathogenic bacterium and a significant cause of nongonococcal urethritis in both men and women. Due to the difficulty of the culture of M. genitalium from clinical samples, the laboratory diagnosis of M. genitalium infection is almost exclusively carried out using nucleic acid amplification tests. Loop-mediated isothermal amplification (LAMP) is a novel nucleic acid amplification technology, utilising a set of 4 primers specific to 6 distinct regions of the target DNA sequence, in order to amplify target DNA in a highly specific and rapid manner. A LAMP assay was designed to the pdhD gene of M. genitalium, and the limit of detection of the assay was determined as 10 fg of M. genitalium genomic DNA, equating to ~16 copies of the M. genitalium genome, which was equally sensitive as a gold standard 16S rRNA polymerase chain reaction assay.

Sensitive Detection of Thirteen Bacterial Vaginosis-Associated Agents Using Multiplex Polymerase Chain Reaction

Bacterial vaginosis (BV) is characterized by a polymicrobial proliferation of anaerobic bacteria and depletion of lactobacilli, which are components of natural vaginal microbiota. Currently, there are limited conventional methods for BV diagnosis, and these methods are time-consuming, expensive, and rarely allow for the detection of more than one agent simultaneously. Therefore, we conceived and validated a multiplex polymerase chain reaction (M-PCR) assay for the simultaneous screening of thirteen bacterial vaginosis-associated agents (BV-AAs) related to symptomatic BV: Gardnerella vaginalis, Mobiluncus curtisii, Mobiluncus mulieris, Bacteroides fragilis, Mycoplasma hominis, Atopobium vaginae, Ureaplasma urealyticum, Megasphaera type I, Clostridia-like bacteria vaginosis-associated bacteria (BVABs) 1, 2, and 3, Sneathia sanguinegens, and Mycoplasma genitalium. The overall validation parameters of M-PCR compared to single PCR (sPCR) were extremely high, including agreement of 99.1% and sensitivity, specificity, and positive predictive values of 100.0%, negative predictive value of 97.0%, accuracy of 99.3%, and agreement with Nugent results of 100.0%. The prevalence of BV-AAs was very high (72.6%), and simultaneous agents were detected in 53.0%, which demonstrates the effectiveness of the M-PCR assay. Therefore, the M-PCR assay has great potential to impact BV diagnostic methods in vaginal samples and diminish associated complications in the near future.

Pathogens in Urine from a Female Patient with Overactive Bladder Syndrome Detected by Culture-independent High Throughput Sequencing: A Case Report

INTRODUCTION

Overactive bladder syndrome (OAB) is described as urgency, with or without urgency incontinence. A range of medical conditions shares the symptoms of OAB, however the diagnosis is contingent on the exclusion of urinary tract infection (UTI). Knowing that urine dipstick and routine culture of bacteria can miss UTI diagnosis caused by low-count bacteriuria or "difficult-to-culture" pathogens, we examined a case of OAB with a culture-independent approach.

CASE PRESENTATION

A 61-year-old Norwegian female with a long history of urinary symptoms and a diagnosis of OAB was selected as a suitable subject for a culture-independent 16S rDNA analysis on the patient´s urine. The patient's medical records showed no history of recurrent UTI, however, when the urine specimen was sent to routine culture at the time of study it showed a significant bacteriuria caused by a single bacterium, and the patient was prescribed antibiotics. The 16S rDNA analysis revealed not one, but many different bacteria, including a considerable amount of fastidious bacteria, indicating a polymicrobial state. One year later, the subject was still experiencing severe symptoms, and a follow-up analysis was performed. This time the urine-culture was negative, however, the 16S rDNA profile was quite similar to that of the first sample, again displaying a complex bacterial profile.

CONCLUSION

The use of 16S rDNA pyrosequencing and sequence analysis to uncover "difficult-to-culture" bacteria should be considered when examining patients with chronic urinary symptoms. These methods may contribute to further elucidation of the etiology of overactive bladder syndrome and other urinary syndromes.

Chlamydia trachomatis and Genital Mycoplasmas: Pathogens with an Impact on Human Reproductive Health

The most prevalent, curable sexually important diseases are those caused by Chlamydia trachomatis (C. trachomatis) and genital mycoplasmas. An important characteristic of these infections is their ability to cause long-term sequels in upper genital tract, thus potentially affecting the reproductive health in both sexes. Pelvic inflammatory disease (PID), tubal factor infertility (TFI), and ectopic pregnancy (EP) are well documented complications of C. trachomatis infection in women. The role of genital mycoplasmas in development of PID, TFI, and EP requires further evaluation, but growing evidence supports a significant role for these in the pathogenesis of chorioamnionitis, premature membrane rupture, and preterm labor in pregnant woman. Both C. trachomatis and genital mycoplasmas can affect the quality of sperm and possibly influence the fertility of men. For the purpose of this paper, basic, epidemiologic, clinical, therapeutic, and public health issue of these infections were reviewed and discussed, focusing on their impact on human reproductive health.

The Maternal Serological Response to Intrauterine Ureaplasma sp. Infection and Prediction of Risk of Pre-Term Birth

Pre-term birth (PTB) associated with intrauterine infection and inflammation (IUI) is the major cause of early PTB less than 32 weeks of gestation. Ureaplasma spp. are common commensals of the urogenital tract in pregnancy and are the most commonly identified microorganisms in amniotic fluid of pre-term pregnancies. While we have an understanding of the causal relationship between intra-amniotic infection, inflammation and PTB, we are still unable to explain why vaginal Ureaplasma sp. colonization is tolerated in some women but causes PTB in others. It is now known that placental tissues are frequently colonized by bacteria even in apparently healthy pregnancies delivered at term; usually this occurs in the absence of a significant local inflammatory response. It appears, therefore, that the site, nature, and magnitude of the immune response to infiltrating microorganisms are key in determining pregnancy outcome. Some evidence exists that the maternal serological response to Ureaplasma sp. colonization may be predictive of adverse pregnancy outcome, although issues such as the importance of virulence factors (serovars) and the timing, magnitude, and functional consequences of the immune response await clarification. This mini-review discusses the evidence linking the maternal immune response to risk of PTB and the potential applications of maternal serological analysis for predicting obstetric outcome.

Detection, characterization, and molecular typing of human Mycoplasma spp. from major hospitals in Cairo, Egypt

Mycoplasmas are fastidious slow growing organisms lacking a cell wall and mostly isolated from the mucosal surfaces of the respiratory and genitourinary tracts. There is a dearth of information regarding clinical Mycoplasma spp. isolates among Egyptian patients. A total of 170 samples were collected from patients and apparently healthy personnel in local public hospitals in Cairo, Egypt. Isolation of Mycoplasma spp. was carried out using appropriate culture media and further identification was carried out by biochemical tests followed by serotyping using specific antisera. Confirmation was done by PCR for detection of different Mycoplasma spp. using genus-specific primers targeting 16S ribosomal RNA gene. Characterization of the antibiotic resistance and sensitivity pattern against different antimicrobials was carried out using disc diffusion test. The results indicated the presence of six Mycoplasma spp. in 22.94% of the samples. Mycoplasmas were detected more frequently in throat swabs than sputum. Mycoplasma pneumoniae was highly sensitive to macrolides and quinolones but less sensitive to aminoglycosides and tetracyclines. Molecular techniques were found to be of more rapid, highly sensitive, able to detect nonviable organisms, and cost effective. These results shed light on difficulties of Mycoplasma detection and the superiority of molecular techniques over culture.

Evaluation of five real-time PCR assays for detection of Mycoplasma pneumoniae

Four commercial real-time PCR assays to detect Mycoplasma pneumoniae were tested, and the results were compared with the results for an in-house approach. Despite differences of crossing threshold values of up to 4, assays were able to detect at least 20 CFU/5 μl (52 fg DNA/5 μl) of sample with the Diagenode kit showing the best clinical sensitivity.

Genetic point-of-care diagnosis of Mycoplasma pneumoniae infection using LAMP assay

BACKGROUND

Mycoplasma pneumoniae (MP) is a major pathogen of lower respiratory tract infection (LRTI) in children. A rapid diagnostic method during the acute phase is required for the prescription of effective antibiotics.

METHODS

A prospective, single-centered study was conducted on community-acquired LRTI in children. We regarded the day of fever onset as the first day of illness. In part 1, we studied 191 patients with signs of LRTI. We compared diagnostic reliability using loop-mediated isothermal amplification (LAMP) assay and serological testing at the first visit. In part 2, we evaluated the clinical characteristics of 117 patients with positive LAMP assay.

RESULTS

In part 1, 31 patients met the definite MP infection criteria. LAMP assay had a sensitivity of 96.8% and specificity of 100%, whereas enzyme immunoassay had a sensitivity of 38.7% and specificity of 76.9%, and particle agglutination test had a sensitivity of 19.4% and specificity of 93.1%. In part 2, of 106 patients with fever, 100 patients were diagnosed by the day 7 of illness. The diagnosis was made a mean of 3.5 ± 2.1 days after the onset of fever.

CONCLUSIONS

LAMP assay had excellent sensitivity and specificity for the detection of acute MP infection at the first visit. This assay can diagnose MP infection during the very acute phase. LAMP assay is appropriate for genetic point-of-care diagnosis of MP infection in hospital laboratories.

Macrophage-activating lipopeptide-2 requires Mal and PI3K for efficient induction of heme oxygenase-1

AIMS

This study is to investigate the mechanisms by which macrophage-activating lipopeptide-2 (MALP-2) induces heme oxygenase (HO)-1, a cytoprotective enzyme that catalyzes the degradation of heme, in human monocytes.

METHODS

Human monocytic THP-1 cells were cultured for transient transfection with plasmids and stimulation with MALP-2 for indicative time intervals. After incubation with MALP-2, cells were collected and disrupted, before being tested for promoter activity using luciferase assay. For analysis of proteins, immunoreactive bands were detected using an enhanced chemiluminescence Western blotting system, and the band intensity was measured by densitometryic analysis. For the detection of co-immunoprecipitation, SDS-PAGE was performed and the membranes were probed using respective antibodies. To investigate the cellular localization of NF-E2-related factor 2 (Nrf2), cells underwent immunofluorescence staining and confocal microscopy, and were analyzed using electrophoretic mobility shift assay.

RESULTS

MALP-2-induced HO-1 expression and promoter activity were abrogated by transfection with dominant negative (DN) plasmids of TLR2 and TLR6, or their neutralizing antibodies. However, inhibition of MyD88 or transfection with the DN-MyD88 was insufficient to attenuate HO-1 expression. In contrast, mutation or silencing of MyD88 adapter-like (Mal) by DN-Mal or siRNA almost completely blocked HO-1 induction. Btk, c-Src and PI3K were also involved in MALP-2-induced HO-1 expression, as revealed by specific inhibitors LFM-A13, PP1 and LY294002, or by transfection with siRNA of c-Src. MALP-2-induced activation of PI3K was attenuated by transfection with DN mutant of Mal, and by pretreatment with LFM-A13 or PP1. Furthermore, MALP-2 stimulated the translocation of Nrf2 from the cytosol to the nucleus and Nrf2 binding to the ARE site in the HO-1 promoter, which could also be inhibited by pretreatment with a PI3K inhibitor, LY294002.

CONCLUSIONS

These results indicated that MALP-2 required TLR2/6, Btk, Mal and c-Src to activate PI3K, which in turn initiated the activation of Nrf2 for efficient HO-1 induction.

Diagnosis of ureaplasma urealyticum septic polyarthritis by PCR assay and electrospray ionization mass spectrometry in a patient with acute lymphoblastic leukemia

We report a case of polyarthritis with axial involvement in a young female patient treated for acute lymphoblastic leukemia. Detection in the hip fluid of Ureaplasma urealyticum by broad-range PCR followed by electrospray ionization mass spectrometry allowed the diagnosis of septic arthritis and ad integrum recovery upon adapted antibiotic therapy.

The emerging role of community sentinel surveillance in the understanding of the clinical features and epidemiology of acute Mycoplasma pneumoniae infection

Retrospective analysis of 3984 test results for the detection of Mycoplasma pneumoniae performed between 2009 and 2013 in Wales was undertaken. Analysis of the clinical presentation of positive cases suggested that mild respiratory infection was common in the community and appeared to coincide with increased hospitalizations. Symptomatic infection was more prevalent in men, with a median age of 22.6 years (range <1-88 years), and 40% of hospitalized cases presented with pneumonia. Inclusion of M. pneumonia nucleic acid amplification tests (NAATs) into routine respiratory NAAT screens will increase the understanding of the epidemiology and clinical spectrum of acute infections in the wider population.

Ureaplasma species: role in neonatal morbidities and outcomes

The genital mycoplasma species, Ureaplasma parvum and Ureaplasma urealyticum are the most common organisms isolated from infected amniotic fluid and placentas, and they contribute to adverse pregnancy outcomes including preterm birth and neonatal morbidities. In our institution, almost half of the preterm infants of less than 32 weeks gestation are Ureaplasma-positive in one or more compartment (respiratory, blood and/or cerebrospinal fluid), indicating that these organisms are the most common pathogens affecting this population. This review will focus on the compelling epidemiological and experimental evidence linking perinatal Ureaplasma species exposure to important morbidities of prematurity, such as bronchopulmonary dysplasia, intraventricular haemorrhage and necrotising enterocolitis.

Comparison of the new Mycofast Revolution assay with a molecular assay for the detection of genital mycoplasmas from clinical specimens

BACKGROUND

Genital mycoplasmas are opportunistic bacteria that are associated with undesirable gynaecologic and reproductive events. Mycoplasmas are fastidious bacteria with increasing resistance to routine antimicrobials and often fail to grow on conventional culture methods. The commercial Mycofast Revolution assay permits the phenotypic detection and identification of genital mycoplasmas. Antimicrobial susceptibility testing against five antimicrobial agents with MICs corresponding to the CLSI guidelines can also be performed. This study aimed to compare the new commercially available Mycofast Revolution assay with a multiplex PCR assay.

METHODS

Self-collected swabs were obtained from pregnant women attending the antenatal clinic of a tertiary academic hospital in Pretoria, South Africa from October 2012 to November 2012. These swabs were used to seed UMMt and modified Amies transport media. The seeded UMMt transported medium was used to inoculate the Mycofast Revolution assay for the identification, enumeration and antimicrobial susceptibility testing of genital mycoplasmas. Following DNA extraction from the modified Amies transport medium, specimens were subjected to a multiplex PCR assay for the detection of genital mycoplasmas.

RESULTS

The Mycofast Revolution kit had a sensitivity and specificity of 77.3% (95% CI: 62.15% to 88.51%) and 80% (95% CI: 28.81% to 96.70%), respectively, against the PCR assay. The positive and negative predictive values were 97.1% (95% CI: 85.03% to 99.52%) and 28.6% (95% CI: 8.57% to 58.08%). Genital mycoplasmas were detected in 71.4% (35/49) of samples with the Mycofast Revolution assay with 49% (24/49) being Ureaplasma spp. and 22.4% (11/49) mixed strains. The multiplex PCR assay had a positivity rate of 89.8% (44/49) for genital mycoplasmas; mixed strains were present in 51% (25/49) of samples, Ureaplasma spp. in 16.3% (8/49) and M. hominis in 22.4% (11/49) of samples.

CONCLUSIONS

There was a fair agreement (κ = 0.319) between the Mycofast Revolution assay and the mPCR assay. With the high prevalence rates of genital mycoplasmas, fast and efficient diagnostic methods are imperative to treat infections and minimise complications. The Mycofast Revolution assay is simple to use, has a short turn-around time and interpretation of results are straightforward. This assay circumvents common problems experienced with conventional culture and molecular methods in diagnostic laboratories where skilled personnel are limited and can be used as an alternative diagnostic assay.

Ureaplasma urealyticum, Mycoplasma hominis and adverse pregnancy outcomes

PURPOSE OF REVIEW

Mycoplasma hominis and Ureaplasma urealyticum may colonize the human genital tract and have been associated with adverse pregnancy outcomes. Chorioamnionitis, spontaneous preterm labour and preterm premature rupture of membranes are significant contributors to neonatal morbidity and mortality. However, as these bacteria can reside in the normal vaginal flora, there are controversies regarding their true role during pregnancy and thus the need to treat these organisms.

RECENT FINDINGS

We review here the recent data on the epidemiology of mycoplasmas and their clinical role during pregnancy. The association of these organisms with preterm labour has been suggested by many observational studies, but proof of causality remains limited. PCR is an excellent alternative to culture to detect the presence of these organisms, but culture allows antibiotic susceptibility testing. Whether antimicrobial treatment of mycoplasma-colonized pregnant patients can effectively reduce the incidence of adverse pregnancy outcomes warrants further investigations.

SUMMARY

The role of Mycoplasma spp. and U. urealyticum in adverse pregnancy outcomes is increasingly accepted. However, sole presence of these microorganisms in the vaginal flora might be insufficient to cause pathological issues, but their combination with other factors such as bacterial vaginosis or cervical incompetence may be additionally needed to induce preterm birth.