Evaluation of GENECUBE Mycoplasma for the detection of macrolide-resistant Mycoplasma pneumoniae

Research status and challenges of Mycoplasma pneumoniae pneumonia in children: A bibliometric and visualization analysis from 2011 to 2023

BACKGROUND

Mycoplasma pneumoniae (MP) infections occur in regional outbreaks every 3 to 7 years, lasting up to 2 years. Since this fall, there has been a significant rise in MP infections among children in China, indicating a regional epidemiological trend that imposes an increased national public health burden. To date, bibliometric methods have not been applied to studies on MP infection in children.

METHODS

We searched for all relevant English publications on MP pneumonia in children published from 2011 to 2023 using Web of Science. Analytical software tools such as Citespace and VOSviewer were employed to analyze the collected literature.

RESULTS

993 articles on MP pneumonia in children were published in 338 academic journals by 5062 authors affiliated with 1381 institutions across 75 countries/regions. China led in global productivity with 56.19%. Among the top 10 prolific organizations, 8 were Chinese institutions, with Soochow University being the most active, followed by Capital Medical University and Zhejiang University. Zhimin Chen from Zhejiang University School of Medicine exhibited the highest H-index of 32. Keyword co-occurrence network analysis revealed 7 highly relevant clusters.

CONCLUSION

The current research hotspots and frontiers in this field are primarily MP pneumonia, refractory MP pneumonia, lactate dehydrogenase, asthma, and biomarker. We anticipate that this work will provide novel insights for advancing scientific exploration and the clinical application of MP pneumonia in children.

Development of a mobile laboratory system in hydrogen fuel cell buses and evaluation of the performance for COVID-19 RT-PCR testing

We designed and developed two new types of hydrogen fuel cell (HFC) buses (motorcoach and minibus) with a mobile laboratory system. Feasibility studies have been performed for mobile laboratory testing, particularly for the laboratory performance of COVID-19 RT-PCR (PCR). We evaluated the driving range capability, PCR sample size capacity, turnaround time (TAT), and analytical performance for the detection of SARS-CoV-2. Saliva samples were used for the current study, and the analytical performance was compared with that of the reference PCR. The estimated driving range and sample size capacity of the HFC and HFC minibus were 432 km and 2847 samples, respectively, for the HFC motorcoach and 313 km and 1949 samples for the HFC minibus. For the TAT, the median time between sample submission and completion of PCR was 86 min for the motorcoach and 76 min for the minibus, and the median time between sample submission and electronic reporting of the result to each visitor was 182 min for the motorcoach and 194 min for the minibus. A secondary analysis of 1574 HFC mobile laboratory testing samples was conducted, and all negative samples were found to be negative by reference PCR. Furthermore, all samples were confirmed to be positive by reference PCR or other molecular examinations.

Recent Trend of Antimicrobial Susceptibility among Mycoplasma pneumoniae Isolated from Japanese Children

Macrolide-resistant Mycoplasma pneumoniae (MRMP) infections have become increasingly prevalent, especially in East Asia. Whereas MRMP strains have point mutations that are implicated in conferring resistance, monitoring the antibiotic susceptibility of M. pneumoniae and identifying mutations in the resistant strains is crucial for effective disease management. Therefore, we investigated antimicrobial susceptibilities among M. pneumoniae isolates obtained from Japanese children since 2011. To establish the current susceptibility trend, we analyzed the minimum inhibitory concentrations (MICs) of M. pneumoniae in recent years (2017−2020) in comparison with past data. Our observation of 122 M. pneumoniae strains suggested that 76 were macrolide-susceptible M. pneumoniae (MSMP) and 46 were macrolide-resistant. The MIC ranges (µg/mL) of clarithromycin (CAM), azithromycin (AZM), tosufloxacin (TFLX), and minocycline (MINO) to all M. pneumoniae isolates were 0.001−>128, 0.00012−>128, 0.25−0.5, and 0.125−4 µg/mL, respectively. None of the strains was resistant to TFLX or MINO. The MIC distributions of CAM and AZM to MSMP and MINO to all M. pneumoniae isolates were significantly lower, but that of TFLX was significantly higher than that reported in all previous data concordant with the amount of recent antimicrobial use. Therefore, continuation of appropriate antimicrobial use for M. pneumoniae infection is important.

Refractory Mycoplasma pneumoniae Pneumonia in Children: Early Recognition and Management

Refractory Mycoplasma pneumoniae pneumonia (RMPP) is a severe state of M. pneumoniae infection that has attracted increasing universal attention in recent years. The pathogenesis of RMPP remains unknown, but the excessive host immune responses as well as macrolide resistance of M. pneumoniae might play important roles in the development of RMPP. To improve the prognosis of RMPP, it is mandatory to recognize RMPP in the early stages, and the detection of macrolide-resistant MP, clinical unresponsiveness to macrolides and elevated proinflammatory cytokines might be clues. Timely and effective anti-mycoplasmal therapy and immunomodulating therapy are the main strategies for RMPP.

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.

The evaluation of the utility of the GENECUBE HQ SARS-CoV-2 for anterior nasal samples and saliva samples with a new rapid examination protocol

INTRODUCTION

GENECUBE® is a rapid molecular identification system, and previous studies demonstrated that GENECUBE® HQ SARS-CoV-2 showed excellent analytical performance for the detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) with nasopharyngeal samples. However, other respiratory samples have not been evaluated.

METHODS

This prospective comparison between GENECUBE® HQ SARS-CoV-2 and reference real-time reverse transcriptase polymerase chain reaction (RT-PCR) was performed for the detection of SARS-CoV-2 using anterior nasal samples and saliva samples. Additionally, we evaluated a new rapid examination protocol using GENECUBE® HQ SARS-CoV-2 for the detection of SARS-CoV-2 with saliva samples. For the rapid protocol, in the preparation of saliva samples, purification and extraction processes were adjusted, and the total process time was shortened to approximately 35 minutes.

RESULTS

For 359 anterior nasal samples, the total-, positive-, and negative concordance of the two assays was 99.7% (358/359), 98.1% (51/52), and 100% (307/307), respectively. For saliva samples, the total-, positive-, and negative concordance of the two assays was 99.6% (239/240), 100% (56/56), and 99.5% (183/184), respectively. With the new protocol, total-, positive-, and negative concordance of the two assays was 98.8% (237/240), 100% (56/56), and 98.4% (181/184), respectively. In all discordance cases, SARS-CoV-2 was detected by additional molecular examinations.

CONCLUSION

GENECUBE® HQ SARS-CoV-2 provided high analytical performance for the detection of SARS-CoV-2 in anterior nasal samples and saliva samples.

Point-of-care molecular diagnosis of Mycoplasma pneumoniae including macrolide sensitivity using quenching probe polymerase chain reaction

Objectives

Macrolides are generally considered to be the drugs of choice for treatment of patients with Mycoplasma pneumoniae infection. However, macrolide-resistant M. pneumoniae has been emerging since about 2000. The Smart Gene^® system (MIZUHO MEDY Co., Ltd., Tosu, Japan) is a novel fully automated system for detection of pathogens using the method of quantitative polymerase chain reaction (qPCR) with QProbe (QProbe PCR). The entire procedure is completed within 50 min and the size of the instrument is small (15 x 34 x 30 cm). The purpose of this study was to evaluate the usefulness of the Smart Gene^® system for detection of M. pneumoniae and detection of a point mutation at domain V of the 23S rRNA gene of M. pneumoniae.

Materials

Pharyngeal swab samples were collected from 154 patients who were suspected of having respiratory tract infections associated with M. pneumoniae.

Results

Compared with the results of qPCR, the sensitivity and specificity of the Smart Gene^® system were 98.7% (78/79) and 100.0% (75/75), respectively. A point mutation at domain V of the 23S rRNA gene was detected from 7 (9.0%) of 78 M. pneumoniae-positive samples by the Smart Gene^® system and these results were confirmed by direct sequencing. The minimum inhibitory concentrations of clarithromycin among the 5 isolates of M. pneumoniae with a point mutation at domain V of the 23S rRNA gene were >64 μg/ml and those among the 33 isolates without a mutation in the 23S rRNA gene were <0.0625 μg/ml.

Conclusion

The Smart Gene^® system is a rapid and accurate assay for detection of the existence of M. pneumoniae and a point mutation at domain V of the 23S rRNA gene of M. pneumoniae at the same time. The Smart Gene^® system is suitable for point-of-care testing in both hospital and outpatient settings.

Clinical Evaluation of a Novel Point-of-Care Assay To Detect Mycoplasma pneumoniae and Associated Macrolide-Resistant Mutations

The recent increase in macrolide-resistant Mycoplasma pneumoniae in Asia has become a continuing problem. A point-of-care testing method that can quickly detect M. pneumoniae and macrolide-resistant mutations (MR mutations) is critical for proper antimicrobial use. Smart Gene (Mizuho Medy Co., Ltd., Tosu City, Saga, Japan) is a compact and inexpensive fully automatic gene analyzer that combines amplification with PCR and the quenching probe method to specify the gene and MR mutations simultaneously. We performed a clinical evaluation of this device and its reagents on pediatric patients with suspected M. pneumoniae respiratory infections and evaluated the impact of the assay on antimicrobial selection. Using real-time PCR as a comparison control, the sensitivity of Smart Gene was 97.8% (44/45), its specificity was 93.3% (98/105), and its overall concordance rate was 94.7% (142/150). The overall concordance rate of Smart Gene diagnosis of MR mutations in comparison with sequence analysis was 100% (48/48). The ratio of MR mutations was significantly higher at high-level medical institutions than at a primary medical clinic (P = 0.023), and changes in antibiotic therapy to drugs other than macrolides were significantly more common in patients with MR mutations (P = 0.00024). Smart Gene demonstrated excellent utility in the diagnosis of M. pneumoniae and the selection of appropriate antimicrobials for MR mutations at primary medical institutions, which play a central role in community-acquired pneumonia care. The use of this device may reduce referrals to high-level medical institutions for respiratory infections, thereby reducing the medical and economic burdens on patients.

A Prospective Evaluation of the Analytical Performance of GENECUBE® HQ SARS-CoV-2 and GENECUBE® FLU A/B

Background

Molecular tests are the mainstay of detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, their accessibility can be limited by the long examination time and inability to evaluate multiple samples at once.

Objective

This study evaluated the analytical performance of the newly developed rapid molecular assays GENECUBE^® HQ SARS-CoV-2 and GENECUBE^® FLU A/B.

Method

This prospective study was conducted between 14 December 2020 and 9 January 2021 at a polymerase chain reaction (PCR) center. Samples were collected from the nasopharynx with flocked swabs. Molecular tests were performed with the GENECUBE^® system and reference reverse transcription (RT)-PCR, and the results of the two assays were compared.

Result

Among 1065 samples, 81 (7.6%) were positive for SARS-CoV-2 on the reference RT-PCR. Three showed discordance between GENECUBE^® HQ SARS-CoV-2 and the reference RT-PCR; the total, positive, and negative samples of concordance for the two assays were 99.7%, 100%, and 99.7%, respectively. All discordant cases were positive with GENECUBE^® HQ SARS-CoV-2 and negative with the reference RT-PCR. SARS-CoV-2 was detected in all three samples using another molecular assay for SARS-CoV-2. For GENECUBE^® FLU A/B, the total, positive, and negative samples of concordance for the two assays were 99.5%, 100%, and 99.1%.

Conclusion

The GENECUBE^® HQ SARS-CoV-2 and GENECUBE^® FLU A/B demonstrated sufficient analytical performance to detect SARS-CoV-2 and influenza virus A/B.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40291-021-00535-5.