Laboratory diagnosis of Mycoplasma pneumoniae infection

Laboratory diagnosis and treatment of Mycoplasma pneumoniae infection in children: a review

Mycoplasma pneumoniae (MP) is the cause of Mycoplasma pneumoniae pneumonia (MPP) in children and adolescents, with the clinical manifestations highlighted by intermittent irritating cough, accompanied by headache, fever and muscle pain. This paper aimed to study the research status and focal points in MP infection, especially the common laboratory diagnostic methods and clinical treatment of Mycoplasma pneumoniae. Laboratory diagnostic methods include molecular assay, serological antibody detection, rapid antigen detection and isolation and culture. Polymerase chain reaction (PCR) is the gold standard with high sensitivity and specificity. The serological antibody can detect various immune antibodies qualitatively or quantitatively in serum. Rapid antigen can be detected faster, with no equipment environment requirements, which can be used for the early diagnosis of MP infection. While the culture growth cycle is long and insensitive, not recommended for routine diagnosis. Macrolides were the preferred drug for children with MPP, while the drug resistance rate was rising in China. Tetracycline can be substituted but was not recommended for children under 8 years of age, quinolone drugs are not necessary, severe MPP can be combined with glucocorticoids, involving the nervous or immune system can choose gamma globulin. Other treatments for MPP including symptomatic treatment which can alleviate symptoms, improve lung function and improve prognosis. A safe and effective vaccine needed to be developed which can provide protective immunity to children and will reduce the incidence of MPP.

New methods to detect bacterial or viral infections in patients with chronic obstructive pulmonary disease

INTRODUCTION

Patients with chronic obstructive pulmonary disease (COPD) are frequently colonized and infected by respiratory pathogens. Identifying these infectious etiologies is critical for understanding the microbial dynamics of COPD and for the appropriate use of antimicrobials during exacerbations.

AREAS COVERED

Traditional methods, such as bacterial and viral cultures, have been standard in diagnosing respiratory infections. However, these methods have significant limitations, including lack of sensitivity and prolonged turnaround time. Modern molecular approaches offer rapid, sensitive, and specific detection, though they also come with their own challenges. This review explores and evaluates the clinical utility of the latest advancements in detecting bacterial and viral respiratory infections in COPD, encompassing molecular techniques, biomarkers, and emerging technologies.

EXPERT OPINION

In the evolving landscape of COPD management, integrating molecular diagnostics and emerging technologies holds great promise. The enhanced sensitivity of molecular techniques has significantly advanced our understanding of the role of microbes in COPD. However, many of these technologies have primarily been developed for pneumonia diagnosis or research applications, and their clinical utility in managing COPD requires further evaluation.

Real-time fluorescent multiple cross displacement amplification for rapid and sensitive Mycoplasma pneumoniae detection

Mycoplasma pneumoniae is a significant pathogen responsible for community-acquired pneumonia, predominantly affecting children and adolescents. Here, we devised a rapid method for M. pneumoniae that combined multiple cross displacement amplification (MCDA) with real-time fluorescence technology. A set of ten primers, which were specifically designed for M. pneumoniae detection, were employed in a real-time fluorescence MCDA reaction. Of these, one primer incorporated a restriction endonuclease recognition sequence, a fluorophore, and a quencher, facilitating real-time fluorescence detection. The real-time (RT)-MCDA reactions were monitored in a simple real-time fluorescence instrument and conducted under optimised conditions (64°C for 40 min). The detection limit of the M. pneumoniae RT-MCDA assay for genomic DNA extracted from M. pneumoniae culture was down to 43 fg/µl. This assay accurately identified M. pneumoniae strains without cross-reacting with other bacteria. To validate its practical application, we tested the M. pneumoniae RT-MCDA assay using genomic DNA extracted from clinical samples. The assay's detection capability proved comparable with real-time PCR, MCDA-based biosensor detection, and visual inspection under blue light. The entire process, including rapid DNA extraction and real-time MCDA detection, was completed within 1 h. Overall, the M. pneumoniae RT-MCDA assay reported here is a simple and effective diagnostic tool for rapid M. pneumoniae detection, which holds significant potential for point-of-care testing and in resource-limited regions.

Application of LAMP coupled with NALF for precise detection of mycoplasma pneumoniae

Mycoplasma pneumoniae (MP),as the most commonly infected respiratory pathogen in community-acquired pneumonia in preschool children,has becoming a prominent factor affecting children's respiratory health.Currently, there is a lack of easy, rapid, and accurate laboratory testing program for MP infection, which causes comparatively difficulty for clinical diagnostic.Here,we utilize loop-mediated isothermal amplification (LAMP) to amplify and characterize the P1 gene of MP, combined with nucleic acid lateral flow (NALF) for fast and visuallized detection of MP.Furthermore, we evaluated and analyzed the sensitivity, specificity and methodological consistency of the method.The results showed that the limit of detection(LoD) of MP-LAMP-NALF assay was down to 100 copys per reaction and there was no cross-reactivity with other pathogens infected the respiratory system. The concordance rate between MP-LAMP-NALF assay with quantitative real-time PCR was 94.3 %,which exhibiting excellent testing performance.We make superior the turnaround time of the MP-LAMP-NALF assay, which takes only about 50 min. In addition, there is no need for precision instruments and no restriction on the laboratory site.Collectively, LAMP-NALF assay targeting the P1 gene for Mycoplasma pneumoniae detection was a easy, precise and visual test which could be widely applied in outpatient and emergency departments or primary hospitals.When further optimized, it could be used as "point-of-care testing" of pathogens or multiple testing for pathogens.

Clinical Value of Different Test Methods in Diagnosing Mycoplasma pneumoniae Infection in Children

This research aimed to investigate the diagnostic value of passive particle agglutination test, Mycoplasma pneumoniae (MP) culture, cold agglutination test (CAT), enzyme-linked immunosorbent assay (ELISA), and polymerase chain reaction-capillary electrophoresis fragment analysis (PCR-CEFA) for MP infection. Children with respiratory tract infections suspected to be MP infection were subjected to passive particle agglutination test, MP culture, CAT, ELISA, and PCR-CEFA. A total of 146 children (81 males, 65 females, mean age: 5.74 ± 3.32 years, and mean course of disease: 9.07 ± 5.18 days) met the inclusion criteria. The positivity rate of MP detection by MP culture was 69.18% (101/146). Using the MP culture method as the standard, higher sensitivity and positive predictive value were found in the PCR-CEFA compared with the other 3 methods. Appropriate methods are selected following the advantages and disadvantages of pathogen detection, and pediatric MP infection is analyzed by integrating various test results.

Navigating the Diagnostic Challenges of Mycoplasma and Legionella Coinfection Through Serological Testing

Diagnosing community-acquired pneumonia (CAP) is increasingly challenging, especially with the emergence of atypical pathogens such as Mycoplasma pneumoniae and Legionella pneumophila. This report presents the case of a 60-year-old male exhibiting lethargy and decreased oral intake, with a medical history marked by chronic kidney disease and benign prostate hyperplasia. Despite a positive Legionella urine antigen, the clinical and radiological profile did not align with Legionella pneumonia. Elevated M. pneumoniae IgM antibody titers further complicated the diagnostic scenario. We explore the complexities of distinguishing coinfection from primary infection, highlight the limitations of serological testing, and promote a comprehensive diagnostic strategy customized to individual patient circumstances. This case emphasizes the importance of comprehensive assessment strategies to understand atypical pneumonia presentations, particularly within complex clinical scenarios.

Diagnostic significance of HRCT imaging features in adult mycoplasma pneumonia: a retrospective study

Mycoplasma pneumoniae pneumonia (MPP) often overlaps with the clinical manifestations and chest imaging manifestations of other types of community-acquired pneumonia (CAP). We retrospectively analyzed the clinical and imaging data of a group of patients with CAP, summarized their clinical and imaging characteristics, and discussed the diagnostic significance of their certain HRCT findings. The HRCT findings of CAP researched in our study included tree-in-bud sign (TIB), ground-glass opacity (GGO), tree fog sign (TIB + GGO), bronchial wall thickening, air-bronchogram, pleural effusion and cavity. The HRCT findings of all cases were analyzed. Among the 200 cases of MPP, 174 cases showed the TIB, 193 showed the GGO, 175 showed the tree fog sign, 181 lacked air-bronchogram. In case taking the tree fog sign and lack of air-bronchogram simultaneously as an index to distinguish MPP from OCAP, the sensitivity was 87.5%, the specificity was 97.5%, the accuracy was 92.5%. This study showed that that specific HRCT findings could be used to distinguish MPP from OCAP. The combined HRCT findings including the tree fog sign and lacked air-bronchogram simultaneously would contribute to a more accurate diagnosis of MPP.

Extra-urogenital infection by Mycoplasma hominis in transplant patients: two case reports and literature review

BACKGROUND

Mycoplasma hominis is a facultative anaerobic bacterium commonly present in the urogenital tract. In recent years, M. hominis has increasingly been associated with extra-urogenital tract infections, particularly in immunosuppressed patients. Detecting M. hominis in a diagnostic laboratory can be challenging due to its slow growth rate, absence of a cell wall, and the requirements of specialized media and conditions for optimal growth. Consequently, it is necessary to establish guidelines for the detection of this microorganism and to request the appropriate microbiological work-up of immunosuppressed patients.

CASE PRESENTATION

We hereby present two cases of solid organ transplant patients who developed M. hominis infection. Microscopic examination of the bronchial lavage and pleural fluid showed no microorganisms. However, upon inoculating the specimens onto routine microbiology media, the organism was successfully identified and confirmation was performed using 16S rDNA sequencing. Both patients received appropriate treatment resulting in the resolution of M. hominis infection.

CONCLUSIONS

The prompt detection of M. hominis in a clinical specimen can have a significant impact on patient care by allowing for early intervention and ultimately resulting in more favorable clinical outcomes, especially in transplant patients.

Pre-Pandemic Distribution of Bacterial Species in Nasopharyngeal Swab Specimens from Pediatric and Adult Patients Detected via RT-PCR Using the Allplex Respiratory Panel

Background: Recently, panel-based molecular diagnostics for the simultaneous detection of respiratory viruses and bacteria in nasopharyngeal swab (NPS) specimens have been highlighted. We identified the distribution of bacterial species in NPS specimens collected from pediatric and adult patients by employing RT-PCR (Allplex respiratory panel 4, RP4, Seegene) to estimate its applicability in a panel-based assay for detecting respiratory viruses. Methods: We used 271 and 173 NPS specimens from pediatric and adult patients, respectively. The results of the Allplex RP4 panel using NPS (NPS-RP4) from adult patients were compared with those of the Seeplex PneumoBacter ACE Detection assay (Seegene), which used sputum for testing (sputum-Seeplex). Results: A total of 147 specimens (54.2%) were positive for the NPS-RP4 panel in pediatric patients. There were 94, 77, 10, 3, 3, and 2 specimens that were positive for Haemophilus influenzae (HI), Streptococcus pneumoniae (SP), Mycoplasma pneumoniae (MP), Chlamydia pneumoniae (CP), Bordetella pertussis (BP), and B. parapertussis (BPP), respectively. Among 173 adult patients, 39 specimens (22.5%) were positive in the NPS-RP4. Thirty specimens were positive for HI, and 13 were positive for SP. One specimen tested positive for both MP and Legionella pneumophila (LP). CP, BP, and BPP results were all negative. However, 126 specimens (72.8%) had positive results with sputum-Seeplex (99 SP, 59 HI, three LP, and two MP), and the overall percentage of agreement between the two assays was 39.3% in the adult patients. Conclusions: Bacterial species in NPS from more than half of pediatric patients were detected. Performing the Allplex RP4 assay with NPS revealed additional respiratory bacteria that are not detected in current clinical practices, which do not include bacterial testing, demanding the use of sputum specimens. However, the use of NPS showed low agreement with standard assays using sputum in adult patients. Thus, more research is needed to develop a reliable RT-PCR method using NPS specimens in adult patients.

Rapid, ultrasensitive and highly specific diagnosis of Mycoplasma pneumoniae by a CRISPR-based detection platform

Mycoplasma pneumoniae (MP) is an important causative agent of morbidity and mortality among all age groups, especially among patients of extreme ages. Improved and readily available tests for accurate, sensitive and rapid diagnosis of MP infection is sorely needed. Here, we developed a CRISPR-Cas12b-based detection platform on the basis of recombinase polymerase amplification (RPA) for rapid, simple, and accurate diagnosis of MP infection, named MP-RPA-CRISPR. The RPA was employed for amplifying the community-acquired respiratory distress syndrome (CARDS) toxin gene of MP strains at the optimal reaction temperature 37°C. The resulting amplicons were decoded by the CRISPR-Cas12b-based detection platform, which was interpreted by real-time PCR system and by naked eye under blue light. The MP-RPA-CRISPR can detected down to 5 fg of genomic DNA templates of MP strains and accurately distinguish MP strains from non-MP strains without any cross-reactivity. A total of 96 bronchoalveolar lavage fluid (BALF)samples collected from patients suspected of respiratory infection were used to evaluate the clinical performance of the MP-RPA-CRISPR assay. As a result, our assay accurately diagnosed 45 MP-infected samples and 51 non-MP infected sample, and the results obtained from MP-RPA-CRISPR were consistent with microfluidic chip technology. In conclusion, our MP-RPA-CRISPR assay is a simple, rapid, portable and highly sensitive method to diagnose MP infection, which can be used as a promising tool in a variety of settings including clinical, field, and resource-limited aeras.

Comparison of serodiagnosis methods for community-acquired Mycoplasma pneumoniae respiratory tract infections in children

This study aimed to evaluate the diagnostic value of chemiluminescence immunoassay (CLIA), passive particle agglutination (PPA), and indirect immunofluorescence assay (IFA) in detecting Mycoplasma pneumoniae infection in children. Serum samples from 165 children with acute community-acquired respiratory tract infections were examined using CLIA, PPA, and IFA, and consistency coefficient, specificity, and sensitivity were analyzed. Compared with the PPA (titer ≥ 1:160), the consistency coefficients of the immunoglobulin(Ig)M-CLIA, immunoglobulin(Ig)G-CLIA and IgM-IFA methods were 93.94%, 75.76%, and 83.64%, respectively. The positive likelihood ratio (PLR) and specificity of IgM-CLIA was 19.40 and 95.49%, respectively. The consistency coefficient of (IgM+IgG)-CLIA and PPA (titer ≥ 1:160) was 89.1%, and the sensitivity and negative predictive value of (IgM+IgG)-CLIA were 96.88% and 98.94%, respectively. CLIA MP-IgM has high concordance with PPA, and its specificity and sensitivity are higher than those of CLIA MP-IgG and IFA MP-IgM, suggesting its better diagnosis of early MP infection. The sensitivity and negative predictive value of CLIA MP (IgM+IgG) were higher than those of PPA or IFA, indicating that it should be considered as a priority in the diagnosis of MP infection.

Heparin-Binding Protein: A Prognostic Biomarker Associated with Severe or Complicated Community-Acquired Pneumonia in Children

Purpose

Heparin-binding protein (HBP) is a novel biomarker for inflammatory diseases. This study aimed to investigate the role of serum HBP in community-acquired pneumonia (CAP) in children and the association of HBP with the severity and prognosis.

Patients and Methods

A total of 125 children with CAP admitted to the hospital were enrolled in this retrospective study. We analyzed the differences in clinical characteristics and examination findings between patients with different levels of HBP. The severe or complicated CAP was defined as having severe radiographic findings and/or systemic manifestations. Receiver operator characteristic (ROC) curves detected the performance of biomarkers in identifying patients with severe or complicated pneumonia. The multivariate logistic regression models assessed the association between HBP levels and the severity and prognosis. Finally, we constructed a predictive model based on HBP.

Results

The rate of severe or complicated CAP for patients with upper-quartile HBP concentration (≥60 ng/mL) was 54.8%, significantly higher than that of patients with lower HBP concentration (26.6%). The level of HBP is substantially correlated with neutrophil counts, C-reactive protein, erythrocyte sedimentation rate, and serum amyloid A protein (r = 0.31, 0.26, 0.36, and 0.26, respectively). HBP achieved the highest level of discrimination for severe or complicated CAP among the biomarkers. Higher HBP concentration (≥60 ng/mL) was associated with a three-fold higher risk of severe or complicated CAP (adjusted odds ratio = 3.11, p < 0.05). A predictive model including four characteristics (HBP, lactate dehydrogenase, age and non-viral infection) for predicting severe or complicated CAP (with area under the ROC curve = 0.75) was built to create a nomogram.

Conclusion

Substantially elevated serum HBP is significantly associated with severe or complicated CAP and poor prognosis in children. This finding warrants further investigation of the function of HBP in the pathogenesis of CAP.

Development and validation of a nomogram for predicting Mycoplasma pneumoniae pneumonia in adults

The study aimed to explore predictors of Mycoplasma pneumoniae pneumonia (MPP) in adults and develop a nomogram predictive model in order to identify high-risk patients early. We retrospectively analysed the clinical data of a total of 337 adult patients with community-acquired pneumonia (CAP) and divided them into MPP and non-MPP groups according to whether they were infected with MP. Univariate and multivariate logistic regression analyses were used to screen independent predictors of MPP in adults and to developed a nomogram model. Receiver operating characteristic (ROC) curve, calibration curve, concordance index (C-index), and decision curve analysis (DCA) were used for the validation of the evaluation model. Finally, the nomogram was further evaluated by internal verification. Age, body temperature, dry cough, dizziness, CRP and tree-in-bud sign were independent predictors of MPP in adults (P < 0.05). The nomogram showed high accuracy with C-index of 0.836 and well-fitted calibration curves in both the training and validation sets. The area under the receiver operating curve (AUROC) was 0.829 (95% CI 0.774-0.883) for the training set and 0.847 (95% CI 0.768-0.925) for the validation set. This nomogram prediction model can accurately predict the risk of MPP occurrence in adults, which helps clinicians identify high-risk patients at an early stage and make drug selection and clinical decisions.

Atypical Pathogens in Adult Community-Acquired Pneumonia and Implications for Empiric Antibiotic Treatment: A Narrative Review

Atypical pathogens are intracellular bacteria causing community-acquired pneumonia (CAP) in a significant minority of patients. Legionella spp., Chlamydia pneumoniae and psittaci, Mycoplasma pneumoniae, and Coxiella burnetii are commonly included in this category. M. pneumoniae is present in 5-8% of CAP, being the second most frequent pathogen after Streptococcus pneumoniae. Legionella pneumophila is found in 3-5% of inpatients. Chlamydia spp. and Coxiella burnetii are present in less than 1% of patients. Legionella longbeachae is relatively frequent in New Zealand and Australia and might also be present in other parts of the world. Uncertainty remains on the prevalence of atypical pathogens, due to limitations in diagnostic means and methodological issues in epidemiological studies. Despite differences between CAP caused by typical and atypical pathogens, the clinical presentation alone does not allow accurate discrimination. Hence, antibiotics active against atypical pathogens (macrolides, tetracyclines and fluoroquinolones) should be included in the empiric antibiotic treatment of all patients with severe CAP. For patients with milder disease, evidence is lacking and recommendations differ between guidelines. Use of clinical prediction rules to identify patients most likely to be infected with atypical pathogens, and strategies of narrowing the antibiotic spectrum according to initial microbiologic investigations, should be the focus of future investigations.

Identification of Mycoplasma pneumoniae-associated pneumonia cases among hospitalized patients using CLART® microarray technology

Objectives

Community-acquired pneumonia (CAP) is a global health condition that affects populations from all age groups. The laboratory identification of Mycoplasma pneumoniae as a causative agent of CAP is challenging because of its atypical and fastidious nature. Therefore, this study assessed the diagnostic potential of PneumoCLART bacteria® in identifying M. pneumoniae as a causative agent of pneumonia in hospitalized adults.

Methods

This prospective study used a cross-sectional approach to assess the diagnostic potential of PneumoCLART bacteria® for detecting M. pneumoniae in sputum samples procured from 27 patients with pneumonia who required hospitalization.

Results

The PneumoCLART bacteria® results illustrated that 7 of 27 patients with pneumonia were positive for M. pneumoniae (26%). However, the quality of sputum varied among the M. pneumoniae-positive and M. pneumoniae-negative samples. Fifty percent of the specimens obtained from patients positive for M. pneumoniae were saliva-contaminated and unsuitable for analysis.

Conclusions

Because the leukocyte count was low and sputum specimens were saliva-contaminated, these findings require further validation to prove the utility of CLART® microarray technology for the identification of M. pneumoniae in pneumonia-positive patients. Conclusively, this prospective study included a small number of clinical samples, which likely affected its outcomes.

Recent Trends in the Epidemiology, Diagnosis, and Treatment of Macrolide-Resistant Mycoplasma pneumoniae

Among Mycoplasma pneumoniae (MP) is one of the major pathogens causing lower respiratory tract infection. Macrolide-resistant Mycoplasma pneumoniae (MRMP) isolates have been increasing and has become a global concern, especially in East Asian countries. This affects the treatment of MP infection; that is, some patients with MRMP infections fever cannot be controlled despite macrolide therapy. Therefore, alternative therapies, including secondary antimicrobials, including tetracyclines, fluoroquinolones, or systemic corticosteroids, were introduced. However, there are insufficient data on these alternative therapies. Thus, this article provides reviews of the recent trends in the epidemiology, diagnosis, and treatment of MRMP.

Mycoplasma pneumoniae Pleural Effusion in Adults

Parapneumonic effusions often complicate Mycoplasma pneumoniae (MP) pneumonia, contrary to the notion that they are a rare feature of MP infection. Increased research and evidence on MP parapneumonic effusions (MPPE) can help elucidate its clinical significance as one of the variable manifestations of MP infection. This article aims to summarize the existing literature about the clinical characteristics of MPPE in adults and discuss its diagnostic implications from the perspective of pleural fluid analysis. Approximately 20–25% of adult patients with MP pneumonia develop MPPE, and its frequency in children and adults seems to be similar. Although the pathogenesis of MPPE remains to be elucidated, MP-induced cell-mediated immune mechanisms might be partially associated with the development of MPPE. MPPE usually shows mononuclear leukocyte predominance with elevated adenosine deaminase (ADA) activity, similar to tuberculous pleural effusion (TPE). The degree of increase in pleural fluid ADA levels and serum inflammatory biomarkers may help differentiate between MPPE and TPE. During the acute phase, a single positive IgM and positive polymerase chain reaction results allow for a precise and reliable MP infection diagnosis. The mainstay of treatment is the selection of adequate anti-mycoplasma antibiotics with or without corticosteroid, based on the local epidemiologic data on macrolide resistance.

Mycoplasma pneumoniae COVID-19 Delta Variant Co-Infection Mimicking COVID-19 ARDS

The Delta variant of COVID-19 has been associated with severe disease causing a surge in the second half of 2021. Atypical pathogens can be present in those in particular with severe ARDS and can contribute to excess morbidity and mortality. We must maintain a high level of suspicion for these pathogens as this can present an opportunity to dramatically improve the prognosis of a patient with COVID-19 ARDS. However, lend caution to Mycoplasma IgM serology as this can be a false-positive. If suspicion remains high for Mycoplasma pneumoniae infection, sputum polymerase chain reaction (PCR) for M pneumoniae is the gold standard for diagnosis. We present the case of a 42-year-old female with COVID-19 Delta variant presumed ARDS who had co-infection with M pneumoniae confirmed by endotracheal sputum aspirate PCR with rapidly improving oxygenation and extubation within 4 days of effective antibiotic therapy.

The investigation of P1 gene in Mycoplasma pneumonia isolated from atypic pneumonia by molecular methods, determine IgG antibody and MIC to ciprofloxacin antibiotic

Mycoplasma pneumoniae, which causes atypical pneumonia, is a well-established pathogen of the respiratory tract. This bacterium is intrinsically susceptible to fluoroquinolones. But recently, drug-resistant forms of this bacterium have been reported. This study aims to determine the prevalence of this bacterium by ELISA and PCR and MIC to ciprofloxacin. The clinical samples (blood and nasopharyngeal swab) were collected from 100 patients, who were referred to selective hospitals in Tehran with respiratory complaints, were enrolled in 2017. Nasopharyngeal swab sample collections were cultured on PPLO broth and PPLO agar. After culturing and DNA extraction, PCR was performed by specific P1 genes primers. Ciprofloxacin's MIC of Mycoplasma pneumonia isolated was determined by the Micro-broth dilution method. The serum of IgG antibody titers was also measured by ELISA Mycoplasma pneumonia. In this study, out of 100 samples, 12 bacteria were isolated on PPLO agar. Using specific primers, 7 samples of Mycoplasma speciesism-specific were positive for the presence of M.pneumoniae and 2 Ciprofloxacin resistant isolates were evaluated. ELISA results show that IgG titer antibody is existent in 19 samples and 5 samples are intermediate as well. IgG antibody titer average in the whole sample is 27/66 U/ml, but it is in Positive samples by P1 PCR is 45/75 U/ml. This study showed that PCR is a sensitive and reliable method for rapid detection of M. pneumoniae bacteria in respiratory infectious samples, but the results of this method are different from the ELISA method. Additionally, it seems that the resistance to ciprofloxacin is relatively common among M. pneumoniae.

Severe pediatric Mycoplasma pneumonia as the cause of diffuse alveolar hemorrhage requiring veno-venous extracorporeal membrane oxygenation: A case report

BACKGROUND

Diffuse alveolar hemorrhage (DAH) is an acute life-threatening disease often associated with immunocompromised patients and systemic disorders, such as infections, vasculitis, and toxins. Mycoplasma pneumoniae is one of the most common causes of community-acquired pneumonia in children, which rarely causes respiratory failure and fulminant disease; However, a rapid progression may occur in some patients. Mycoplasma pneumonia-associated DAH is rare.

CASE PRESENTATION

We report a case of severe pediatric mycoplasma pneumonia in an immuno-competent child. This patient's condition progressed rapidly, with severe lung lesions associated with pleural effusion, coagulopathy, diffuse alveolar haemorrhage and severe respiratory distress requiring ventilator and intravenous extracorporeal membrane oxygenation (VV-ECMO) support. She was discharged upon successful treatment.

CONCLUSION

Diffuse alveolar hemorrhage associated with Mycoplasma pneumoniae in children is very rare, and clinicians should be aware of the potential rapid onset of the disease. Early detection and diagnosis are very important. The main treatment measures include anti-infection and supportive measures such as mechanical ventilation, but as in our case, success with both prone positioning for more than 10 h per day and VV-ECMO was life-saving.

Mycoplasma pneumoniae IgG positivity is associated with tic severity in chronic tic disorders

Infectious pathogens may represent an environmental risk factor for chronic tic disorders (CTD). This cross-sectional study aimed to determine whether Mycoplasma pneumoniae (M. pneumoniae) IgG positivity is associated with the presence or severity of tics. We compared M. pneumoniae IgG positivity across three groups: children and adolescents (3-16 years) with CTD (CTD group; n = 302); siblings (3-10 years) of people with CTD who developed tics within a seven-year follow-up period (tic onset group; n = 51); siblings (4-10 years) who did not develop tics within the study period and were ≥10-years-old at their last assessment (unaffected group; n = 88). The relationship between M. pneumoniae IgG positivity and the presence and severity of tics was analysed using multilevel models controlling for site, family relatedness, sex, age, presence of comorbid obsessive-compulsive and/or attention-deficit/hyperactivity disorder and use of psychotropic medication. M. pneumoniae IgG positivity was not associated with the presence of CTD, or the first onset of tics as compared to siblings who remained unaffected. M. pneumoniae IgG positivity was associated with a higher tic severity score within the CTD group (β = 2.64, s.e. = 1.15, p = 0.02). It is possible that M. pneumoniae infection influences tic severity in CTD or, that having more severe tics, increases the risk of infection. However, it is more likely that the association observed in this study reflects a propensity toward enhanced immune responses in people with CTD and that, rather than a causal relationship, infection and greater tic severity are indirectly linked via shared underlying immune mechanisms.

Rapid Assay for Sick Children with Acute Lung infection Study (RASCALS): diagnostic cohort study protocol

INTRODUCTION

Lower respiratory tract infection (LRTI) is the most commonly treated infection in critically ill children. Pathogens are infrequently identified on routine respiratory culture, and this is a time-consuming process. A syndromic approach to rapid molecular testing that includes a wide range of bacterial and fungal targets has the potential to aid clinical decision making and reduce unnecessary broad spectrum antimicrobial prescribing. Here, we describe a single-centre prospective cohort study investigating the use of a 52-pathogen TaqMan array card (TAC) for LRTI in the paediatric intensive care unit (PICU).

METHODS AND ANALYSIS

Critically ill children with suspected LRTI will be enrolled to this 100 patient single-centre prospective observational study in a PICU in the East of England. Samples will be obtained via routine non-bronchoscopic bronchoalveolar lavage which will be sent for standard microbiology culture in addition to TAC. A blood draw will be obtained via any existing vascular access device. The primary outcomes of the study will be (1) concordance of TAC result with routine culture and 16S rRNA gene sequencing and (2) time of diagnostic result from TAC versus routine culture. Secondary outcomes will include impact of the test on total antimicrobial prescriptions, a description of the inflammatory profile of the lung and blood in response to pneumonia and a description of the clinical experience of medical and nursing staff using TAC.

ETHICS AND DISSEMINATION

This study has been approved by the Yorkshire and the Humber-Bradford Leeds Research Ethics Committee (REC reference 20/YH/0089). Informed consent will be obtained from all participants. Results will be published in peer-reviewed publications and international conferences.

TRIAL REGISTRATION NUMBER

NCT04233268.

Chronic Fatigue Syndrome: A Case Report Highlighting Diagnosing and Treatment Challenges and the Possibility of Jarisch-Herxheimer Reactions If High Infectious Loads Are Present

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex multi-system disease with no cure and no FDA-approved treatment. Approximately 25% of patients are house or bedbound, and some are so severe in function that they require tube-feeding and are unable to tolerate light, sound, and human touch. The overall goal of this case report was to (1) describe how past events (e.g., chronic sinusitis, amenorrhea, tick bites, congenital neutropenia, psychogenic polydipsia, food intolerances, and hypothyroidism) may have contributed to the development of severe ME/CFS in a single patient, and (2) the extensive medical interventions that the patient has pursued in an attempt to recover, which enabled her to return to graduate school after becoming bedridden with ME/CFS 4.5 years prior. This paper aims to increase awareness of the harsh reality of ME/CFS and the potential complications following initiation of any level of intervention, some of which may be necessary for long-term healing. Treatments may induce severe paradoxical reactions (Jarisch–Herxheimer reaction) if high infectious loads are present. It is our hope that sharing this case will improve research and treatment options for ME/CFS.

Development of an immunochromatographic test for the detection of Mycoplasma pneumoniae GroES antigen

Mycoplasma pneumoniae frequently causes community-acquired pneumonia in children; β-lactam antibiotics are ineffective against this bacterium because of its lack of a cell wall. Hence, a rapid and simple detection method is required to ensure appropriate treatment. In this study, we developed a rapid and simple immunochromatography-based detection method using monoclonal antibodies that react with the co-chaperone GroES of M. pneumoniae. Mice were immunized with recombinant GroES, and hybridoma cells producing anti-GroES monoclonal antibodies were established. For the development of the immunochromatographic test, antibody pairs with superior reactivity and specificity were selected. The developed immunochromatographic test could detect 0.1 ng/mL of recombinant GroES within 20 min. Moreover, no cross-reaction was observed with other microorganisms, including six Mycoplasma species, 20 other bacterial species, and one yeast species. Macrolide-resistant and -susceptible M. pneumoniae clinical isolates were detected at approximately 10⁴ to 10⁵ colony-forming units/mL. The study indicates that immunochromatographic tests targeting GroES are useful for rapid and simple detection of M. pneumoniae.

A 3D-Printed Microfluidic Device for qPCR Detection of Macrolide-Resistant Mutations of Mycoplasma pneumoniae

Mycoplasma pneumonia (MP) is a common respiratory infection generally treated with macrolides, but resistance mutations against macrolides are often detected in mycoplasma pneumoniae in China. Rapid and accurate identification of mycoplasma pneumoniae and its mutant type is necessary for precise medication. This paper presents a 3D-printed microfluidic device to achieve this. By 3D printing, the stereoscopic structures such as microvalves, reservoirs, drainage tubes, and connectors were fabricated in one step. The device integrated commercial polymerase chain reaction (PCR) tubes as PCR chambers. The detection was a sample-to-answer procedure. First, the sample, a PCR mix, and mineral oil were respectively added to the reservoirs on the device. Next, the device automatically mixed the sample with the PCR mix and evenly dispensed the mixed solution and mineral oil into the PCR chambers, which were preloaded with the specified primers and probes. Subsequently, quantitative real-time PCR (qPCR) was carried out with the homemade instrument. Within 80 min, mycoplasma pneumoniae and its mutation type in the clinical samples were determined, which was verified by DNA sequencing. The easy-to-make and easy-to-use device provides a rapid and integrated detection approach for pathogens and antibiotic resistance mutations, which is urgently needed on the infection scene and in hospital emergency departments.

Infective Endocarditis Secondary to Mycoplasma pneumoniae

Mycoplasma pneumoniae (MP) is a gram-positive bacterium most commonly associated with community-acquired pneumonia in adults. It can also involve other systems of the body. Cardiovascular complications include pericarditis, myocarditis, congestive cardiac failure, and, rarely, infective endocarditis. We report a case of infective endocarditis secondary to MP infection in an adult. We treated our patient with doxycycline, which showed significant improvement.

Atypical case of mild encephalopathy/encephalitis with reversible splenial lesion of the corpus callosum (MERS) associated with Mycoplasma pneumoniae infection in a paediatric patient

Mild encephalopathy with reversible splenial lesion (MERS) is a disorder characterised by prodromal symptoms such as fever, cough, vomiting or diarrhoea, followed by mild encephalopathy 1-7 days later with a documented reversible corpus callosum splenial lesion. MERS is mostly reported in children in the region of East Asia. To the best of our knowledge, this is the first reported case of MERS associated with mycoplasma infection in a child in North America. A brief review of literature is also a part of this report.

Hemin activation abrogates Mycoplasma hyorhinis replication in chronically infected prostate cancer cells via heme oxygenase-1 induction

Mycoplasma hyorhinis (M. hyorhinis) lacks a cell wall and resists multiple antibiotics. We describe here the striking > 90% inhibitory effect of hemin, a natural inducer of the cytoprotective enzyme heme oxygenase‐1 (HO‐1), on M. hyorhinis replication in chronically infected LNCaP prostate cancer cells. The role of HO‐1 in interrupting M. hyorhinis replication was confirmed by HO‐1‐specific siRNA suppression of hemin‐induced HO‐1 protein expression, which increased intracellular M. hyorhinis DNA levels in LNCaP cells. Proteomic analysis and transmission electron microscopy of hemin‐treated cells confirmed the complete absence of M. hyorhinis proteins and intact microorganisms, respectively, strongly supporting these findings. Our study is the first to our knowledge suggesting therapeutic potential for activated HO‐1 in cellular innate responses against mycoplasma infection.

Mycoplasma-induced Stevens-Johnson syndrome/toxic epidermal necrolysis: Case-control analysis of a cohort managed in a specialized center

BACKGROUND

Mycoplasma pneumoniae (MP) infection is associated with extrapulmonary complications such as Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN).

OBJECTIVE

We evaluated the differences in epidemiology, clinical characteristics, and disease outcomes between drug-induced and Mycoplasma-related SJS/TEN.

METHODS

All patients with SJS/TEN admitted to our center between 2003 and 2016 inclusive were treated under a standardized protocol. Comparative analysis was made between patients who tested positive for MP versus a control group with negative MP serology in the presence of high-notoriety drugs defined by an algorithm for assessment of drug causality in epidermal necrolysis >5.

RESULTS

Of 180 cases of SJS/TEN patients treated in our institution, 6 had positive MP serologies and were compared to a control group of 71 cases of drug-induced SJS/TEN with an algorithm for assessment of drug causality in epidermal necrolysis score of >5. There were no significant differences in baseline characteristics, disease classification, body surface area involved, and extent of mucosal involvement. We found significant differences in mortality rates between the Mycoplasma and control groups on discharge (0% vs 22.5%, P < .001) and at 1-year follow up (0% vs 32.4%, P = .002), respectively.

LIMITATIONS

Retrospective design, small sample size.

CONCLUSION

Although recent studies have shown that MP-induced SJS/TEN is morphologically different and deserves a separate classification system, this would need to be borne out in larger prospective studies.

Severe Pediatric Mycoplasma pneumoniae Infection Requiring Veno-venous Extracorporeal Membrane Oxygenation

Mycoplasma pneumoniae (MP) is an atypical bacterial pathogen that typically causes mild respiratory symptoms. Rarely, MP is associated with acute respiratory distress syndrome, a condition marked by widespread inflammation in the lungs that often requires invasive support. We report a case of severe acute respiratory distress syndrome requiring veno-venous extracorporeal membrane oxygenation in an otherwise healthy adolescent because of MP.

[Clinical implications of the genus Mycoplasma]

Dentro del género Mycoplasma, las especies que tradicionalmente se han relacionado con cuadros infecciosos han sido principalmente M. pneumoniae, M. genitalium, M. hominis o U. urealyticum. Sin embargo, existen otras muchas que están implicadas y, que muchas veces, son desconocidas para los profesionales sanitarios. El objetivo de esta revisión es identificar todas las especies del género Mycoplasma que se han aislado en el hombre y determinar su participación en la patología infecciosa humana.

Evaluation of the CARDS toxin and its fragment for the serodiagnosis of Mycoplasma pneumoniae infections

Mycoplasma pneumoniae (M. pneumoniae) is an important pathogen in community-acquired pneumonia. The community-acquired respiratory distress syndrome (CARDS) toxin is the only known virulence factor of M. pneumoniae. It is worth exploring whether this toxin can be used as a candidate antigen for the serodiagnosis of M. pneumoniae. In this study, the full-length, N-terminal, and C-terminal regions of the CARDS toxin were expressed and purified, and serological reactions were evaluated using ELISA. A total of 184 serum samples were collected and tested using a commercialized test kit. Eighty-seven samples were positive, and 97 samples were negative for infection. The purified recombinant proteins were used as antigens to test the serum via indirect ELISA. The sensitivity of the CARDS toxin, the N-terminal region, and the C-terminal region were 90.8%, 90.8%, and 92.0%, respectively. The specificity of the CARDS toxin, the N-terminal region, and the C-terminal region were 85.6%, 73.2%, and 93.8%, respectively. All three CARDS toxin proteins exhibited good reactivity, of which the C-terminal region had a good discrimination ability in human sera. This may have a potential diagnostic value for M. pneumoniae infections.

Mycoplasma pneumoniae: a pathogen with unsolved therapeutic problems

INTRODUCTION

Despite the amount of new information, the most effective approach for the diagnosis and treatment of Mycoplasma pneumoniae infections is not established. In this narrative review the pharmacological options for macrolide-resistant (ML) M. pneumoniae infections in children are discussed.

AREAS COVERED

Despite significant improvement in the diagnosis and in the definition of diseases potentially associated with this pathogen, not all the problems related to M. pneumoniae infection are solved. True epidemiology of M. pneumoniae diseases and the real role of this pathogen in extra-respiratory manifestations is still unestablished. This reflects on therapy. It is not known whether antibiotics are really needed in all the cases, independently of severity and localization. The choice of antibiotic therapy is debated as it is not known whether ML resistance has clinical relevance. Moreover, not precisely defined is the clinical importance of corticosteroids for improvement of severe cases, including those associated with ML-resistant strains.

EXPERT OPINION

Improvement in M. pneumoniae identification is mandatory to reduce antibiotics overuse , especially in the presence of ML-resistant strains. Priority for future studies includes the evaluation of the true benefit of therapeutic approaches including corticosteroids in patients with severe CAP and in those with extra-respiratory M. pneumoniae diseases.

Proteomic and mechanistic study of Qingxuan Tongluo formula and curcumin in the treatment of Mycoplasma pneumoniae pneumonia

OBJECTIVE

Mycoplasma pneumoniae (MP) is the only pathogen in the Mycoplasma family that can cause respiratory symptoms, including acute upper respiratory tract infection and bronchitis, which are often attributed to Mycoplasma pneumoniae pneumonia (MPP). MPP is one of the diseases that commonly affects the pediatric respiratory system, but its pathogenesis is unclear. This study investigated the therapeutic effects and mechanisms of Qingxuan Tongluo formula and its main component, curcumin, on MPP.

METHODS

A mouse model of MPP was obtained by nasal drip of the MP strain. The effects of Qingxuan Tongluo formula and curcumin on the treatment of MPP were studied. The proteomic profiles of the alveolar lavage fluid of mice in the model group, Qingxuan Tongluo formula group and curcumin group were evaluated by LC-MS/MS. ELISA and immunohistochemistry were used to verify the possible presence of MP infection biomarkers and drug target proteins.

RESULTS

Compared with the mice in the model group, the MPP mice in the Qingxuan Tongluo formula group had significantly reduced fever and cough and prolonged the cough incubation period. Moreover, the pulmonary pathology of the MPP mice was significantly improved, and the lung histopathological score was decreased. After treatment with Qingxuan Tongluo formula and curcumin, the functional and pathway abnormalities caused by MP were mainly inhibited. Levels of HSP90AA1, GRP94, ENO1 and PLG expression were verified by ELISA and immunohistochemistry.

CONCLUSION

Qingxuan Tongluo formula significantly reduced fevers and cough and prolonged the cough incubation period of MPP mice. Qingxuan Tongluo formula and curcumin significantly improved the pathological changes in lung tissue caused by MP infection. Proteomics analyses indicated that Qingxuan Tongluo formula and curcumin may have therapeutic effects on MPP by regulating energy metabolism, relieving oxidative stress and activating the fibrinolytic system. ENO1 and PLG were found to be potential drug targets.

Frequency of Mycoplasma pneumoniae, Legionella pneumophila and Chlamydia spp. among patients with atypical pneumonia in Tehran

Mycoplasma pneumoniae, Legionella pneumophila and Chlamydia pneumoniae are the most common bacterial agents, which account for 15-40%, 2-15% and 5-10% of atypical community-acquired pneumonia (CAP) respectively. These agents are mostly associated with infection in the outpatient setting. The aim of this study was to evaluate the frequency of these pathogens among patients with CAP attending outpatient clinics in Tehran. A cross-sectional study was carried out of 150 patients attending to educational hospitals in Tehran with CAP. M. pneumoniae, L. pneumophila and Chlamydia spp. were detected by PCR assay, targeting the P1 adhesion gene, macrophage infectivity potentiator (mip) gene and 16S rRNA gene respectively from throat swabs obtained from each patient. A total of 86 (57.3%) of 150 patients were women; median age was 50 years (interquartile range, 35-65 years). M. pneumoniae, L. pneumophila and Chlamydia spp. were detected in 37 (24.7%), 25 (16.7%) and 11 (7.3%) patients respectively; of these, 66 patients (44%) were infected at least by one of these three pathogens. The frequency of L. pneumophila was significantly higher among patients over 60 years old (p 0.03). Coinfection was detected in seven patients (4.7%); six were infected by M. pneumoniae and L. pneumophila, and only one was infected by L. pneumophila and Chlamydia spp. M. pneumoniae was the most prevalent agent of atypical CAP, and L. pneumophila was more likely to infect elderly rather than younger people. Further studies on the prevalence of CAP and its aetiologic agents are needed to improve the diagnosis and treatment of CAP patients.

Comparison of Nucleic Acid Amplification and IgM Tests for the Diagnosis of Mycoplasma pneumoniae Infection in Children During a Recent Korean Outbreak

OBJECTIVE

In the absence of standardized methods for Mycoplasma pneumoniae detection, we evaluated the diagnostic value of polymerase chain reaction (PCR) and IgM assays for detecting M. pneumoniae infection in children during a recent Korean outbreak.

METHODS

The diagnostic performances of PCR and IgM assays for M. pneumoniae in 1,109 clinical specimens were evaluated by the Japanese Respiratory Society (JRS) scoring system as an interim reference standard.

RESULTS

The level of agreement between both tests was fair. As analyzed by the JRS scoring system, the sensitivity of PCR was 45.2% in the group aged <5 years, 86.8% in the group aged 5 years to 10 years group, and 72.2% in the group aged 10 years to 18 years; the sensitivity of the IgM assay was 66.8%, 71.4%, and 55.6% in each group, respectively.

CONCLUSION

The sensitivity of PCR is relatively low but is superior to that of IgM assays such that diagnostic performance can be improved by both test methods in patients aged <5 years.

Mycoplasma pneumoniae in Children With and Without Community-acquired Pneumonia. What do PCR and Serology Say?

BACKGROUND

IgM titers of Mycoplasma pneumoniae can remain high for months or years, and specific DNA can be detected in asymptomatic people.

METHODS

We compared the performance of serology and PCR in children with and without community-acquired pneumonia (CAP) for the diagnosis of M. pneumoniae.

RESULTS

In children with CAP, a positive test by M. pneumoniae (PCR and/or paired serology or both) were found in 13.9%. Of these, 10.3% were positive by multiplex PCR (Seeplex-Seegen), and 6.7% exhibited quadrupled titers (22 for IgG, 6 for IgM and 5 for both). Both tests were positive in 2.8% of cases. In the group without CAP, 3.3% were positive by PCR. Thirty-two percent of children with CAP and 38.3% of healthy children had IgM titers >11 in the acute phase.

CONCLUSIONS

The detection of IgM is not useful for diagnosing acute M. pneumoniae infection, and a positive PCR result can be due to colonization and not infection. New and better diagnostic techniques are required.

Presenting characteristics, comorbidities, and outcomes of patients coinfected with COVID-19 and Mycoplasma pneumoniae in the USA

Coronavirus disease 2019 (COVID‐19) caused by severe acute respiratory syndrome‐coronavirus 2 (SARS‐CoV‐2) is spreading at a rapid pace, and the World Health Organization declared it as pandemic on 11 March 2020. Mycoplasma pneumoniae is an "atypical" bacterial pathogen commonly known to cause respiratory illness in humans. The coinfection from SARS‐CoV‐2 and mycoplasma pneumonia is rarely reported in the literature to the best of our knowledge. We present a study in which 6 of 350 patients confirmed with COVID‐19 were also diagnosed with M. pneumoniae infection. In this study, we described the clinical characteristics of patients with coinfection. Common symptoms at the onset of illness included fever (six [100%] patients); five (83.3%) patients had a cough, shortness of breath, and fatigue. The other symptoms were myalgia (66.6%), gastrointestinal symptoms (33.3%‐50%), and altered mental status (16.7%). The laboratory parameters include lymphopenia, elevated erythrocyte sedimentation rate, C‐reactive protein, lactate dehydrogenase, interleukin‐6, serum ferritin, and D‐dimer in all six (100%) patients. The chest X‐ray at presentation showed bilateral infiltrates in all the patients (100%). We also described electrocardiogram findings, complications, and treatment during hospitalization in detail. One patient died during the hospital course.

The COVID‐19 pneumonia is a serious condition and can be associated with the common respiratory pathogens. Co‐infections with COVID‐19 can result in protracted respiratory symptoms, prolonged ICU stay, morbidity, and mortality if not detected and treated appropriately. The treatment of Co‐infection if y available might facilitate early recovery.

Challenges and countermeasures of thoracic oncology in the epidemic of COVID-19

Since December, 2019, a 2019 novel coronavirus disease (COVID-19) infected by the severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) emerged in Wuhan, Hubei province, and the epidemic situation has continued to spread globally. The epidemic spread of COVID-19 has brought great challenges to the clinical practice of thoracic oncology. Outpatient clinics need to strengthen the differential diagnosis of initial symptoms, pulmonary ground-glass opacity (GGO), consolidation, interstitial and/or interlobular septal thickening, and crazy paving appearance. In the routine of oncology, the differential diagnosis of adverse events from COVID-19 is also significant, including radiation pneumonitis, checkpoint inhibitor pneumonitis (CIP), neutropenic fever, and so on. During the epidemic, indications of transbronchial biopsy (TBB) and CT-guided percutaneous thoracic biopsy are strictly controlled. For patients who are planning to undergo biopsy operation, screening to exclude the possibility of COVID-19 should be carried out. For confirmed or suspected patients, three-level protection should be performed during the operation. Disinfection and isolation measures should be strictly carried out during the operation. At last, more attention to the protection of cancer patients and give priority to the treatment of infected cancer patients.

Immunochromatography for the diagnosis of Mycoplasma pneumoniae infection: A systematic review and meta-analysis

The aim of this study was to evaluate the diagnostic performance of immunochromatographic tests (ICTs) for the detection of Mycoplasma pneumoniae. Medline/Pubmed, Embase, the Cochrane Library, and ISI Web of Science were searched through June 12, 2019 for relevant studies that used ICTs for the detection of M. pneumoniae infection with polymerase chain reaction (PCR) or microbial culturing as reference standards. Pooled diagnostic accuracy with 95% confidence interval (CI) was calculated using a bivariate random effects model. We also constructed summary receiver operating characteristic curves and calculated the area under the curve (AUC). Statistical heterogeneity was evaluated by χ² test or Cochrane’s Q test. Thirteen studies including 2,235 samples were included in the meta-analysis. The pooled sensitivity and specificity for diagnosing M. pneumoniae infection were 0.70 (95% CI: 0.59–0.79) and 0.92 (95% CI: 0.87–0.95), respectively. The positive likelihood ratio (LR) was 8.94 (95% CI: 4.90–14.80), negative LR 0.33 (95% CI: 0.22–0.46), diagnostic odds ratio 29.20 (95% CI: 10.70–64.20), and AUC 0.904. In subgroup analysis, ICTs demonstrated similar pooled sensitivities and specificities in populations of children only and mixed populations (children + adults). Specimens obtained from oropharyngeal swabs exhibited a higher sensitivity and specificity than those of nasopharyngeal swab. Moreover, pooled estimates of sensitivity and accuracy for studies using PCR as a reference standard were higher than those using culture. The pooled sensitivity and specificity of Ribotest Mycoplasma^®, the commercial kit most commonly used in the included studies, were 0.66 and 0.89, respectively. Overall, ICT is a rapid user-friendly method for diagnosing M. pneumoniae infection with moderate sensitivity, high specificity, and high accuracy. This suggests that ICT may be useful in the diagnostic workup of M. pneumoniae infection; however, additional studies are needed for evaluating the potential impact of ICT in clinical practice.

Diagnostic value of quantitative MP-IgG for Mycoplasma pneumoniae pneumonia in adults

The passive particle agglutination (PA) test, once widely used for Mycoplasma pneumoniae (M. pneumoniae) antibody detection, has gradually been replaced by quantitative enzyme-linked immunosorbent assays (ELISA). However, the lack of diagnostic criteria for quantitative ELISA M. pneumoniae-IgG (MP-IgG) and the low positive rates of ELISA M. pneumoniae-IgM (MP-IgM) limit the diagnostic value of ELISA for M. pneumoniae infection in adults. Here, the diagnostic value of quantitative ELISA MP-IgG was evaluated in adults with Mycoplasma pneumoniae pneumonia (MPP). The serum M. pneumoniae antibodies were detected in 162 patients with MPP, 228 patients with community-acquired pneumonia (CAP) with non-Mycoplasma pneumoniae (NMP), and 162 healthy controls by ELISA, using the PA results as the reference standards. For the MP-IgM-/IgG+ subgroup, a single serum MP-IgG level of ≥92.67 RU/mL can be used as a reference criterion for the diagnosis of acute M. pneumoniae infection. At admission, for patients with CAP, the sensitivity and specificity of ELISA MP-IgM positivity for MPP were 18.51% and 99.56%, respectively. MP-IgM positivity combined with MP-IgG ≥ 92.67 RU/mL increased the sensitivity to 40.12% and decreased the specificity to 94.29%. For paired serum samples obtained within seven days, an ELISA MP-IgG concentration change of ≥1.48-fold and MP-IgG ≥ 92.67 RU/mL on day 7 were used as the diagnostic criteria for M. pneumoniae infection. Accordingly, the combination of qualitative MP-IgM detection and quantitative MP-IgG detection by ELISA is valuable for acute MPP diagnosis in adults.

Real-Time PCR and Quantitative Culture for Mycoplasma pneumoniae Load in Pharyngeal Swabs from Children at Preliminary Diagnosis and Discharge

Background

Extensive studies have focused on the diagnosis and treatment of Mycoplasma pneumoniae infection; however, rare studies investigated the posttreatment conditions. We analyzed the carrying status of M. pneumoniae in the respiratory tract of children before and after treatment.

Methods

Ninety-two children with M. pneumoniae pneumonia were included in this study. Clinical data were obtained from each patient, and pharyngeal swab sampling was performed at preliminary diagnosis and discharge. Real-time PCR and dilution quantitative culture were utilized to determine the DNA quantification and number of viable M. pneumoniae from samples collected upon preliminary diagnosis and discharge.

Results

All the 92 cases showed DNA positivity upon preliminary diagnosis, serum IgM antibody was detected in 80 patients, and positivity of M. pneumoniae culture was observed in 82 cases. Upon discharge, the M. pneumoniae nucleotide and culture positivity were detected in 87 and 49 cases, respectively. The content of viable M. pneumoniae was 10–10⁴ CCU/mL and 10–10² CCU/mL in the preliminary diagnosis samples and discharge samples, respectively.

Conclusions

Real-time PCR was rapid and effective for the qualitative diagnosis of M. pneumoniae at the early stage, but it cannot be used to evaluate the prognosis of patients with M. pneumoniae infection. Quantitative analysis for M. pneumoniae DNA could not directly reflex the viable strain content.

A systematic review and meta-analyses of the association between 4 mycoplasma species and lower respiratory tract disease in dogs

Background

The pathogenic role of mycoplasmas in the lower respiratory tract (LRT) of dogs is debated, because mycoplasmas can be isolated from both healthy and sick dogs.

Objectives

To critically assess available data from controlled observational studies on the role of 4 mycoplasma species in LRT disease of dogs.

Design

Systematic review and meta‐analyses.

Methods

Seven electronic databases were searched for relevant publications. Risk of bias was assessed by the Newcastle‐Ottawa Scale. Meta‐analyses, stratified by mycoplasmal species, were performed using a random effects Bayesian model with noninformative priors to estimate pooled odds ratios (ORs) and 95% confidence intervals (CIs) for the association between Mycoplasma cynos, Mycoplasma canis, Mycoplasma spumans, and Mycoplasma edwardii and LRT disease in dogs.

Results

Five studies were included from 1201 references identified. All studies dealt with M. cynos, whereas 3 dealt with the other mycoplasma species. A significant association was found between M. cynos and LRT disease (Bayesian OR, 3.60; CI, 1.31‐10.29). Conversely, M. canis, M. spumans, and M. edwardii were not significantly associated with LRT signs (Bayesian OR, 1.06; CI, 0.10‐14.63; Bayesian OR, 3.40; CI, 0.16‐54.27; and Bayesian OR, 1.04; CI, 0.05‐23.54, respectively).

Conclusions and Clinical Importance

Results support a pathogenic role of M. cynos and a commensal role of M. canis and M. edwardii in LRT in dogs. Although the association was not significant based on the CI, the point estimate of the Bayesian OR was relatively high for M. spumans, making its role less clear. Mycoplasma cynos‐specific polymerase chain reaction should be considered on samples from dogs with LRT.

The crosstalk between microbiome and asthma: Exploring associations and challenges

With the advancement of high‐throughput DNA/RNA sequencing and computational analysis techniques, commensal bacteria are now considered almost as important as pathological ones. Understanding the interaction between these bacterial microbiota, host and asthma is crucial to reveal their role in asthma pathophysiology. Several airway and/or gut microbiome studies have shown associations between certain bacterial taxa and asthma. However, challenges remain before gained knowledge from these studies can be implemented into clinical practice, such as inconsistency between studies in choosing sampling compartments and/or sequencing approaches, variability of results in asthma studies, and not taking into account medication intake and diet composition especially when investigating gut microbiome. Overcoming those challenges will help to better understand the complex asthma disease process. The therapeutic potential of using pro‐ and prebiotics to prevent or reduce risk of asthma exacerbations requires further investigation. This review will focus on methodological issues regarding setting up a microbiome study, recent developments in asthma bacterial microbiome studies, challenges and future therapeutic potential.

Treatment of community-onset pneumonia in neutropenic cancer patients: β-lactam monotherapy versus combination antibiotic regimens

Background

Although β-lactam monotherapy may be sufficient in non-critically ill patients with community-acquired pneumonia, the value of combination antibiotic regimens in community-onset neutropenic pneumonia remains unclear.

Methods

A retrospective cohort study was conducted to compare the effects of combination antibiotic regimens to those of β-lactam monotherapy in cancer patients with community-onset neutropenic pneumonia. Electronic medical records of patients diagnosed with community-onset neutropenic pneumonia between March 1995 and February 2015 at a tertiary care center were reviewed.

Results

During the study period, 165 cancer patients with community-onset neutropenic pneumonia were identified. Seventy-two patients received β-lactam monotherapy and 93 received combination therapy (β-lactam plus either a macrolide or fluoroquinolone). Causative pathogens were identified in 27.9% of the patients, and only two were positive for atypical pathogens. Although 30-day mortality was higher in the β-lactam group (15.3% versus 4.3%; P = 0.015), combination therapy was not associated with a statistically significant survival benefit in the multivariate analysis (hazard ratio 0.85, 95% confidence interval 0.20–3.67; P = 0.827). Duration of neutropenia, C-reactive protein level, and Multinational Association for Supportive Care in Cancer risk index were significant factors for 30-day mortality. In a subgroup analysis of patients treated with cefepime, the most frequently used β-lactam (63.0%), combination therapy also showed no significant survival benefit.

Conclusions

Combination antibiotic regimens were not associated with a survival benefit over β-lactam monotherapy in the treatment of community-onset neutropenic pneumonia. Unnecessary combination therapy should be reconsidered in cancer patients who are at high risk for adverse drug reactions and colonization with multi-drug resistant organisms.

Electronic supplementary material

The online version of this article (10.1186/s41479-019-0061-1) contains supplementary material, which is available to authorized users.

Identfication of viral and bacterial etiologic agents of the pertussis-like syndrome in children under 5 years old hospitalized

BACKGROUND

Acute respiratory infections (ARIs) represent an important cause of morbidity and mortality in children, remaining a major public health concern, especially affecting children under 5 years old from low-income countries. Unfortunately, information regarding their epidemiology is still limited in Peru.

METHODS

A secondary data analysis was performed from a previous cross-sectional study conducted in children with a probable diagnosis of Pertussis from January 2010 to July 2012. All samples were analyzed via Polymerase Chain Reaction (PCR) for the following etiologies: Influenza-A, Influenza-B, RSV-A, RSV-B, Adenovirus, Parainfluenza 1 virus, Parainfluenza 2 virus, Parainfluenza 3 virus, Mycoplasma pneumoniae and Chlamydia pneumoniae.

RESULTS

A total of 288 patients were included. The most common pathogen isolated was Adenovirus (49%), followed by Bordetella pertussis (41%) from our previous investigation, the most prevelant microorganisms were Mycoplasma pneumonia (26%) and Influenza-B (19.8%). Coinfections were reported in 58% of samples and the most common association was found between B. pertussis and Adenovirus (12.2%).

CONCLUSIONS

There was a high prevalence of Adenovirus, Mycoplasma pneumoniae and other etiologies in patients with a probable diagnosis of pertussis. Despite the presence of persistent cough lasting at least two weeks and other clinical characteristics highly suspicious of pertussis, secondary etiologies should be considered in children under 5 years-old in order to give a proper treatment.

Early Diagnosis of Mycoplasma pneumoniae in Children: Simultaneous Amplification and Testing (SAT) Is the Key

Objective: The effective diagnosis of Mycoplasma pneumoniae (MP) pneumonia (MPP) in children has been hampered by the difficulty of achieving an early diagnosis. The simultaneous amplification and testing (SAT) has the potential for early diagnosis of MP in children. Methods: Of the 1,180 children enrolled in this study, 169 were MPP antibody (Ab) seroconversion positive, 641 showed MPP positivity with a single Ab test, and 370 were MPP negative. Sera and pharyngeal swabs were collected for antibody testing and SAT detection, respectively, on admission. When the samples were Ab negative, the paired -Ab test was requested for MP 7 days later. Results: Using the Ab results as the diagnostic standard, the sensitivity, specificity, positive predictive values (PPV), and negative predictive values (NPV) for SAT were 72.8, 95.1, 97.0, and 61.5%, respectively. SAT had superior diagnostic value in the MPP group who had undergone Ab seroconversion (sensitivity: 82.2%; NPV: 92.1%) and in the short-course group also (sensitivity: 81.0%; NPV: 81.3%). Good agreement was observed between SAT and the paired-Ab results (kappa value = 0.79; P < 0.001), but there was a lack of consistency between SAT and the single-Ab test results on admission (kappa value = 0.54, P < 0.001). Conclusions: SAT is a rapid, sensitive, and specific method for MP diagnosis in pediatric patients. Our results indicate its value as an effective diagnostic tool for detecting MPP at the initial stage of an infection.