Mycoplasma pneumoniae Infections: Pathogenesis and Vaccine Development

Epidemiological and clinical characteristics of hospitalized pediatric patients with Mycoplasma pneumoniae pneumonia before and after the COVID-19 pandemic in China: a retrospective multicenter study

BACKGROUND

In China many respiratory pathogens stayed low activities amid the COVID-19 pandemic due to strict measures and controls. We here aimed to study the epidemiological and clinical characteristics of pediatric inpatients with Mycoplasma pneumoniae pneumonia (MPP) after the mandatory COVID-19 restrictions were lifted, in comparison to those before the COVID-19 pandemic.

METHODS

We here included 4,296 pediatric patients with MPP, hospitalized by two medical centers in Jiangsu Province, China, from January 2015 to March 2024. Patients were divided into the pre-COVID (n = 1,662) and post-COVID (n = 2,634) groups. Their baseline characteristics, laboratory test results and radiological patterns were separately assessed and compared between the two groups to determine the substantial changes in the disease profile of MPP after the COVID-19 pandemic.

RESULTS

Epidemiological results suggested a higher annual incidence of MPP after the COVID-19 pandemic when the outbreak reached a peak in October, two months delayed in seasonality compared to that in the pre-COVID era. For pediatric patients with MPP, there was no difference in their median ages, gender ratios, and severe case percentages between the two groups, where most patients were younger than 14 years old. With significance, the post-COVID group had more occurrences of cough and expectoration and higher incidences of influenza A/B virus (IAV/IBV) co-infection than the pre-COVID group. Many hematological parameters and radiological features between the two groups displayed alteration, but comparatively there demonstrated no worsened severity in hospitalized children with MPP after COVID-19 pandemic. Concurrently, the post-COVID group was administered with fewer antibiotics but more corticosteroids for effective treatment than the pre-COVID group.

CONCLUSION

Through the COVID-19 pandemic, the epidemiological and clinical characteristics of pediatric patients with MPP differed, but there was no evident change in the disease severity. After the COVID-19 pandemic, the increased incidence of IAV/IBV co-infection may contribute to the differences in clinical symptoms and hematological profiles, while the adding usage of corticosteroids might treat more effectively.

The reduced interaction between SufS and SufU in Mycoplasma penetrans results in diminished sulfotransferase activity

Mycoplasma Penetrans (Mpe) is an AIDS-related mycoplasma that is also closely related to respiratory diseases. Proteins involved in the first phase of Fe-S cluster biosynthesis in the SUF-like pathway are essential in Gram-positive bacteria because there is no redundant Fe-S cluster biosynthetic pathway in these proteins. In this study, we characterized two essential proteins: cysteine desulphurase (MpeSufS) and sulfurtransferase (MpeSufU) in Mpe, and resolved their crystal structures. Our results reveal that MpeSufS belongs to type II cysteine desulfurase, and MpeSufU is a Zn2+-containing sulfurtransferase. Residue Q342 in MpeSufS and the zinc atom in MpeSufU mediate sulfur transfer from MpeSufS to MpeSufU. Mutation of Q342 significantly impacts the cysteine desulfurase activity. This study provides new insights into the regulation of the activity of the SufS-SufU complex, which will help guide the design of drugs for the treatment of mycoplasma infections.

Establishment of a rapid detection method for Mycoplasma pneumoniae based on RPA-CRISPR-Cas12a technology

Mycoplasma pneumoniae can cause respiratory infections and pneumonia, posing a serious threat to the health of children and adolescents. Early diagnosis of Mycoplasma pneumoniae infection is crucial for clinical treatment. Currently, diagnostic methods for Mycoplasma pneumoniae infection include pathogen detection, molecular biology techniques, and bacterial culture, all of which have certain limitations. Here, we developed a rapid, simple, and accurate detection method for Mycoplasma pneumoniae that does not rely on large equipment or complex operations. This technology combines the CRISPR-Cas12a system with recombinase polymerase amplification (RPA), allowing the detection results to be observed through fluorescence curves and immunochromatographic lateral flow strips.It has been validated that RPA-CRISPR/Cas12a fluorescence analysis and RPA-CRISPR/Cas12-immunochromatographic exhibit no cross-reactivity with other common pathogens, and The established detection limit was ascertained to be as low as 102 copies/µL.Additionally, 49 clinical samples were tested and compared with fluorescence quantitative polymerase chain reaction, demonstrating a sensitivity and specificity of 100%. This platform exhibits promising clinical performance and holds significant potential for clinical application, particularly in settings with limited resources, such as clinical care points or resource-constrained areas.

The novel pleuromutilin derivative 22-((4-((4-nitrophenyl)acetamido)phenyl)thio)deoxy pleuromutilin possesses robust anti-mycoplasma activity both in vitro and in vivo

Objective

Mycoplasmas are structurally simple pathogenic microorganisms that can cause a wide range of diseases in humans and animals and conventional antibiotic therapies of fluoroquinolones and tetracyclines are toxic to young children and young animals and macrolide resistance is increasing. In this context, new anti-mycoplasma antimicrobial agents need to be developed. 22-((4-((4-nitrophenyl)acetamido)phenyl)thio)deoxypleuromutilin (compound 16C) is a novel acetamine phenyl pleuromutilin derivative. This study aimed to evaluate its acute toxicity in mice and generate pharmacokinetic and anti-mycoplasma profiles.

Methods

The safety of compound 16C was preliminarily evaluated by oral and intramuscular acute toxicity tests and single intravenous and intramuscular pharmacokinetic experiments were performed to obtain its pharmacokinetic profile. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and time-killing curves reflected the in vitro effects of the compounds against Mycoplasma pneumoniae. Five groups consisted of three treatments for compound 16C (20, 40, and 80 mg/kg), and two treatments for tiamulin (oral and intramuscular 40 mg/kg) were continued for 4 d. Bronchoalveolar lavage fluid (BALF) and lung tissues were collected at the end of treatment (96 h) and 4 days later (192 h) to assess the in vivo anti-mycoplasma and anti-pneumonia effects. ELISA assays were performed to detect IFN-γ, TNF-α, and IL-8 (CXCL1) in BALF. Lung tissues were fixed with 4% paraformaldehyde and sectioned for histopathological assessment.

Results

The results show that compound 16C has low toxicity (LD50 > 5,000 mg/kg). Its pharmacokinetic profile is characterized by a short time to maximum concentration (Tmax = 0.24 h), high bioavailability (F = 71.29%), and short elimination half-life (T1/2kel) (intramuscular and intravenous administration was 2.20 and 1.89 h, respectively). Treatment with compound 16C and intramuscular tiamulin reduced the mycoplasma load in mice. Intramuscular compound 16C and tiamulin also inhibited the release of IFN-γ, TNF-α, and CXCL1, decreasing the accumulation of inflammatory cells in the lungs, thereby mitigating lung damage.

Conclusion

This study proved that compound 16C has a strong antimicrobial effect against M. pneumoniae, can be rapidly absorbed and has therapeutic efficacy that provides a basis for developing new anti-mycoplasma drugs.

Reviewing advancement in Mycoplasma pneumoniae P30 adhesin protein provides insights for future diagnosis and treatment

Mycoplasma pneumoniae is a major pathogen that causes upper and lower respiratory tract infections in children, adolescents, and elderly individuals and can lead to pneumonia, intrapulmonary and extrapulmonary complications, and respiratory sequelae. M. pneumoniae must adhere to respiratory epithelial cells of a host for infection. The P1 and P30 proteins, as two adhesin proteins of M. pneumoniae, have attracted extensive attention from many researchers. In this paper, we present the latest research progress on the P30 protein in terms of structure and mutation typing, physiological function, clinical serological diagnosis and vaccine development in a literature review. This study deepens our knowledge on the pathogenesis of M. pneumoniae and is useful for diagnosing and preventing M. pneumoniae infection.

The prevalence of Mycoplasma pneumoniae in children in Shandong, China before, during, and after COVID-19

Background

The multifaceted non-pharmaceutical interventions after the outbreak of the COVID-19 pandemic not only limited the spread of SARS-CoV2 but also had an impact on the prevalence of other pathogens.

Methods

In this work, we retrospectively analyzed the epidemiological characteristics of Mycoplasma pneumoniae (MP) in children before and after the COVID-19 pandemic in Shandong, China. From 2019-2023, there were 29,558 visits of pediatric patients (1 month to 15 years old) with respiratory tract infection (RTI) symptoms at a tertiary hospital in Shandong Province, 10,039 of which were positive for MP according to a passive agglutination assay of the serum IgM antibodies. Conduct statistical analysis and epidemiological investigation of the test results categorized by years, months, ages, genders and clinical diagnosis. Utilize the χ 2 test to analyze the differences in incidence rates.

Results

Compared to 2019, the number of visits and the positive cases both decreased substantially in 2020, but the positivity rate increased. Both 2021 and 2023 were peak years of MP infection. The peak seasons of MP infection were fall and winter, female patients had higher positivity rate than male patients, and school-age children (>6 years) had higher positivity rate than the children in other age groups. In terms of the clinical manifestation of MP infection, compared to 2019, in 2023, the proportion of bronchopneumonia and upper RTI decreased significantly.

Conclusions

The ongoing surveillance of the epidemiology of MP is critical for effective disease management and provides a basis for diagnosis, treatment, and the corresponding prevention and control strategies. This work for the first time characterized the epidemiology of MP in Shandong before and after the COVID-19 pandemic, thus providing valuable information for monitoring and preventing MP infection in the post-epidemic era.

Risk association model for atelectasis complication in Mycoplasma pneumoniae pneumonia patients following standardized treatment

Background

Mycoplasma pneumoniae pneumonia (MPP) is a common disease of childhood pneumonia, and atelectasis is a serious comorbidity. Traditional diagnostic methods for MPP are limited by low accuracy, emphasizing the need for improved diagnostic approaches. This study aimed to establish a predictive scoring model for early detection of MPP complicated with atelectasis following standardized treatment.

Methods

A total of 572 children were retrospectively enrolled, including 40 patients with MPP complicated by atelectasis despite standardized treatment and 532 patients in the non-atelectasis group. Clinical, laboratory, and imaging data within 24 h of admission were collected, including demographic information and various biomarkers. Multivariate logistic regression analysis was employed to identify risk factors and construct a predictive model, evaluated using receiver operating characteristic (ROC) curve analysis.

Results

Significant differences were observed between the MPP complicated with atelectasis group and the non-atelectasis group in terms of age, hospital admission time, fever duration, neutrophil percentage and count, CRP, ALT, and LDH levels (P < 0.05). According to the multivariate logistic regression analysis, length of fever, neutrophil ratio, platelet count, ALT, LDH, age were incorporated into the nomogram. The predictive model exhibited a sensitivity of 87.97% and specificity of 77.50% according to the ROC curve.

Conclusion

Our study presents a preliminary risk association model incorporating clinical indicators such as fever duration, neutrophil ratio, platelet count, ALT value, LDH value, and age to aid in the early prediction of atelectasis in children with MPP. Given the methodological limitations, the generalizability of our findings is constrained, and this model should be viewed as an initial framework for clinical assessment rather than a definitive tool.

Reemergence of Mycoplasma pneumoniae disease: Pathogenesis and new approaches

The review discusses the recurrence of Mycoplasma pneumoniae (M. pneumoniae), a bacterium causing atypical pneumonia, primarily affecting Europe and Asia due to climate change, immunity decline, antibiotic resistance, and genetic heterogeneity. The COVID-19 pandemic initially reduced M. pneumoniae cases due to preventative measures, but its reemergence suggests different transmission dynamics and exacerbates clinical severity with co-infections with other viruses. The pathogenicity of M. pneumoniae is attributed to its intracellular changes, toxin release, and adhesion processes, which can result in a variety of symptoms and problems. Antibiotics and immunomodulators are used in treatment, and attempts are being made to create vaccines. Effective management of its reappearance necessitates surveillance and preventative measures, especially in the context of co-infections and potential outbreaks. M. pneumoniae's resurgence highlights its reliance on a polarized cytoskeletal architecture for host cell attachment and pathogenicity through cytoadherence and cytotoxic agent synthesis. M. pneumoniae has returned even though the COVID-19 pandemic originally reduced incidence; this might be because of things like declining immunity and particular pathogenic characteristics. Meteorological factors like temperature and humidity, along with air quality, including pollutants like PM2.5 and NO2, increase susceptibility to environmental hazards. During the pandemic, non-pharmaceutical measures decreased transmission but did not eradicate the infection. Epidemics typically occur three to five years apart, emphasizing the need for ongoing study and observation. Antimicrobial resistance is a serious issue, necessitating caution and alternative therapies, especially in macrolides. COVID-19 pandemic lessons, such as mask use and hand hygiene, may help limit M. pneumoniae transmission.

The protective effect and immunomodulatory ability of orally administrated Lacticaseibacillus rhamnosus GG against Mycoplasma pneumoniae infection in BALB/c mice

Mycoplasma pneumoniae represents one of the significant etiologies of community-acquired pneumonia in pediatric patients. However, clinical treatment of M. pneumoniae infection in children has encountered challenges due to the escalating resistance to quinolones. Numerous studies have highlighted the potential of probiotic lactobacillus administration in boosting immune responses to bacterial and viral respiratory infections. In this study, the protective efficacy of pre-oral administration of Lacticaseibacillus rhamnosus GG (LGG), Limosilactobacillus reuteri F275, Lactiplantibacillus plantarum NCIMB 8826, L. plantarum S1 or L. plantarum S2 was evaluated in the BALB/c mice model; it was observed that among these five strains of lactobacillus, the supplementation of LGG exhibited the most significant protective effect against M. pneumoniae infection. Moreover, when administered orally, both live LGG and heat-inactivated LGG have demonstrated efficacy in reducing the burden of M. pneumoniae in the lungs and alleviating pulmonary inflammation. Oral supplementation with LGG resulted in the inhibition of neutrophil recruitment into the lungs and increased recruitment of alveolar macrophages in M. pneumoniae-infected mice. Additionally, LGG supplementation led to increased production of IL-10 and secretory IgA (sIgA), while suppressing the levels of IL-1β, IL-6, IL-17A, and TNF-α in the lungs of mice infected with M. pneumoniae. The data suggests that supplementation with LGG can modulate immune responses, decrease pathogen load, and alleviate inflammatory injury in the lungs of M. pneumoniae-infected mice.

Impact of the COVID-19 pandemic on epidemiological and clinical characteristics of Mycoplasma pneumoniae pneumonia in children: a multicenter study from Hubei, China

Aims

To investigate the epidemiological and clinical characteristics of children with Mycoplasma pneumoniae pneumonia (MPP) in Hubei, China.

Methods

We retrospectively analyzed inpatients with MPP from 20 hospitals in Hubei, China from January 2021 to December 2022. The co-detected pathogens of Mycoplasma pneumoniae (M. pneumoniae) were investigated using targeted next-generation sequencing (tNGS), and 23S rRNA gene mutations were analyzed to assess the macrolide resistance.

Results

M. pneumoniae infected 20.7% of patients with CAP, with cough (96.59%) and fever (80.28%) being the most prevalent symptoms. The infection rates in children younger than 1, 1-2, 3-6, 7-12, and older than 12 years were 6.17%, 19.98%, 26.97%, 43.93%, and 2.95%, respectively. Among 1,349 patients undergoing tNGS, the overall co-detection rate was 59.45%, with Streptococcus pneumoniae (29.30%), Haemophilus influenzae (23.57%), and Human rhinovirus (17.21%) being the most commonly co-detected pathogens. In 635 patients undergoing the 23S rRNA gene mutation test, 86.30% exhibited positive mutations (A2063G, 98.00%; A2064G, 1.50%; A2067G, 0.50%). Despite a significant age difference (P = 0.037) between macrolide-resistant M. pneumoniae and macrolide-sensitive M. pneumoniae groups, there were no significant differences in symptoms, lab data, or disease severity.

Conclusions

In Hubei Province, the prevalence of exhibited consistent changes during the COVID-19 pandemic. MPP was prevalent year-round, particularly in summer and autumn, with school-age children being more susceptible. Co-detections of viruses and bacteria were frequent in MPP cases, and macrolide resistance exceeded 85%. Ongoing surveillance of M. pneumoniae in children is crucial for understanding the healthcare impact of MPP.

Immunostimulation Signaling via Toll-like Receptor 2 Activation: A Molecular Mechanism of Lactococcus lactis OTG1204 In Vitro and In Vivo

INTRODUCTION

The immune system's defense against pathogens involves innate and adaptive responses, crucial in maintaining overall health. Immunosuppressed states render individuals more susceptible to potential diseases, indicating the need for effective strategies to bolster immune functions.

OBJECTIVES

Although the immunostimulatory effects of various probiotics have been studied, the specific effects and molecular mechanisms of Lactococcus lactis OTG1204 (OTG1204) remain unknown. In this study, the aim was to investigate the molecular mechanisms of OTG1204 in RAW 264.7 macrophages, the key effector cells of the innate immune system involved in host defense and inflammatory responses. Additionally, in this study, the effects of OTG1204 on cyclophosphamide (CTX)-induced immunosuppression states were investigated, thereby demonstrating its potential as an immune stimulant.

METHODS

To assess the macrophage activation ability and underlying mechanisms of OTG1204, RAW 264.7 cells were utilized with transfection, enzyme-linked immunosorbent assay, and quantitative real-time PCR analyses. Furthermore, to evaluate the immunostimulatory effects under immunosuppressed conditions, CTX-induced immunosuppression mice model was employed, and analyses were performed using hematoxylin and eosin staining, flow cytometry, and microbiota examination.

RESULTS

OTG1204 activated RAW 264.7 macrophages, leading to increased production of nitric oxide, prostaglandin E2, and cytokines. This immune activation was mediated through the upregulation of toll-like receptor 2, which subsequently activated the nuclear factor-κB (NF-kB) and mitogen-activated protein kinase (MAPK)/activator protein 1 (AP-1) pathways, thereby stimulating the immune response. In CTX-treated mice, OTG1204 recovered body weight, spleen, and mesenteric lymph node indices, and natural killer cell activity. It re-established populations of innate and adaptive immune cells and activated T cells to secrete cytokines. We also examined the gut barrier integrity and microbiota composition to assess OTG1204's impact on intestinal health, as these factors play a significant role in immune enhancement. OTG1204 enhanced gut barrier integrity by upregulating mucin 2 and tight junction proteins and modulated the gut microbiota by restoring the Firmicutes/Bacteroidetes balance and reducing the abundance of Actinobacteria and Tenericutes.

CONCLUSION

These results suggest that OTG1204 may serve as an effective probiotic for immune enhancement and gut health management by targeting the NF-κB and MAPK/AP-1 pathways, with minimal side effects.

Mycoplasma pneumoniae regulates the expression of GP130 in lung epithelial cells through apoptosis and TLR4/ NF-κB pathway during infection

In previous study, lower levels of serum GP130 were reported in children with MPP. GP130 is an important signal transducer, the down regulation of which may influence host immune responses. In this study, we aimed to analyze the regulatory mechanism of GP130 during MP infection. Firstly, the mRNA and protein levels of GP130 both decrease and then increase with increasing multiplicity of infection (MOI: 1 to 40) of MP. The lowest levels of GP130 were detected at MOI of 5. Then, heat treated MP but not trypsin treated MP or MP extracted proteins show regulatory effect to the expression of GP130. These indicate that the down regulation of GP130 is related to protein mediate adhesion process of MP. Gene expression analysis revealed that MP affected apoptosis and the TLR4 pathway in infected cells, and the mRNA level of IL-6 was correlated with that of GP130. Further, Z-VAD-FMK (pan-caspase inhibitor) can suppress the apoptosis induced by MP infection and restore GP130 at protein level. Further studies revealed that MP infection promoted TLR4 internalization but did not activate the NF-κB pathway. The levels of surface TLR4 showed correlation with the transcription of IL-6 and GP130. TAK242 (TLR4 inhibitor) and PS341 (proteasome inhibitor) can restore the decreased transcription of GP130, both of which were able to promote NF-κB pathway activation in MP-infected cells. These suggested that the regulation of TLR4/NF-κB pathway and induced apoptosis post MP infection are involved in the down-regulation of GP130 at transcription and protein levels, respectively.

The Clinical Significance of Pathogen Loads and Macrolide Resistance Levels for Macrolide-Resistant Mycoplasma pneumoniae Pneumonia in Children

Objective

Mycoplasma pneumoniae (M. pneumoniae) pneumonia presses a serious threat on children's health. This study was aimed to investigate the clinical significance of pathogen loads and macrolide resistance levels for macrolide-resistant M. pneumoniae (MRMP)-induced pneumonia in children.

Methods

Serum levels of inflammatory markers including lactic dehydrogenase (LDH), D-dimer, C-reactive protein (CRP) were tested. RT‒PCR was used for the detection of M. pneumoniae infection and the macrolide resistance levels. The patients were classified into high pathogen load and low pathogen load groups based on the Ct values of the p1 gene, and high macrolide resistance level and low macrolide resistance level groups based on the relative levels of macrolide resistance associated mutations to that of the p1 gene. The rates of alternative antibiotic use and hospitalization days were recorded, and the leukocyte counts were tested.

Results

The rates of elevated inflammatory markers from high to low were LDH, CRP and D-dimer. The Ct values of the p1 gene ranged from 19 to 35, and patients with higher pathogen loads had greater rates of alternative antibiotic use; higher levels of LDH, D-dimer, CRP and neutrophil counts (NEUT); and longer hospitalization durations. The range of the macrolide resistance levels was 0.31-2.11, and the rates of alternative antibiotic use, NEUT, CRP and D-dimer levels were higher in patients with higher macrolide resistance levels.

Conclusion

LDH was a more frequently elevated serum inflammatory marker than D-dimer and CRP, and the pathogen load and macrolide resistance levels possessed important clinical significance for MRMP-induced pneumonia in children.

Single-cell transcriptome atlas revealed bronchoalveolar immune features related to disease severity in pediatric Mycoplasma pneumoniae pneumonia

The mechanisms underlying protective immunity in mild Mycoplasma pneumoniae pneumonia (MPP) and the pathogenesis of severe MPP, characterized by dysregulated immune responses, remain unclear. Here, we performed single-cell RNA sequencing (scRNA-seq) to profile bronchoalveolar lavage fluid (BALF) samples from 13 healthy donors and 24 hospitalized pediatric patients with MPP, covering both mild and severe cases. Severe MPP patients exhibited high levels of exhausted T cells and M1-like macrophages, with the exhaustion of T cells attributed to persistent type I interferon signaling and inadequate assistance from CD4+ T cells. Significant cell-cell interactions between exhausted T cells and programmed death-ligand 1+ (PD-L1+) macrophages were detected in severe patients, potentially mediated through inhibitor molecules (e.g., PD1) and their receptors (e.g., PD-L1), as well as human leukocyte antigen class I molecules and their receptors (e.g., KLRC1/D2), resulting in the dysfunction of anti-MP immune responses. Mild MPP patients were featured by an increased abundance of neutrophils, coupled with enhanced activation, contributing to protective immunity. Together, our study provides a detailed characterization of the BALF immune landscape in MPP patients, revealing distinct immune characteristics between mild and severe cases, which offers a valuable resource for understanding MPP immunopathogenesis and formulating effective therapeutic strategies.

Predictive value of immune-related parameters in severe Mycoplasma pneumoniae pneumonia in children

Background

The severity of Mycoplasma pneumoniae pneumonia (MPP) is strongly correlated with the extent of the host's immune-inflammatory response. In order to diagnose the severity of MPP early, this study sought to explore the predictive value of immune-related parameters in severe MPP (sMPP) in admitted children.

Methods

We performed a database analysis consisting of patients diagnosed at our medical centers with MPP between 2021 and 2023. We included pediatric patients and examined the association between complete blood cell count (CBC), lymphocyte subsets and the severity of MPP. Binary logistic regression was performed to identify the independent risk factors of sMPP. Receiver operating characteristic (ROC) curves were used to estimate discriminant ability.

Results

A total of 245 MPP patients were included in the study, with 131 males and 114 females, median aged 6.0 [interquartile range (IQR), 4.0-8.0] years, predominantly located in 2023, and accounted for 64.5%. Among them, 79 pediatric patients were diagnosed as sMPP. The parameters of CBC including white blood cell (WBC) counts, neutrophil counts, monocyte counts, platelet counts, and neutrophil-to-lymphocyte ratio (NLR), were higher in the sMPP group (all P<0.05). The parameters of lymphocyte subsets including CD3+ T cell ratio (CD3+%) and CD3+CD8+ T cell ratio (CD3+CD8+%), were lower in the sMPP group (all P<0.05). And CD3-CD19+ B cell ratio (CD3-CD19+%) was higher in the sMPP group. Logistic regression analysis showed that age, CD3-CD19+%, and monocyte counts were identified as independent risk factors for the development of sMPP (all P<0.001). The three factors were applied in constructing a prediction model that was tested with 0.715 of the area under the ROC curve (AUC). The AUC of the prediction model for children aged ≤5 years was 0.823 and for children aged >5 years was 0.693.

Conclusions

The predictive model formulated by age, CD3-CD19+%, and monocyte counts may play an important role in the early diagnosis of sMPP in admitted children, especially in children aged ≤5 years.

Epidemiological trends in respiratory pathogens infections among children post-COVID-19: A cross-sectional study

Objective

The aim of this study was to investigate the epidemiological trend of respiratory pathogens infections among children after the Coronavirus Disease 2019 (COVID-19) pandemic.

Methods

This study enrolled 575,373 children who came to our hospital for relevant respiratory pathogen antigen/antibody testing due to respiratory symptoms such as fever and cough. The demographic and laboratory data, including age, gender, testing time, and influenza A virus (IAV), influenza B virus (IBV), respiratory syncytial virus (RSV), adenovirus (ADV), and Mycoplasma pneumonia (MP) results, were collected from electronic medical records. SPSS (version 21.0) and GraphPad Prism 9 software were used for statistical analysis and figure creation.

Results

79,746 children tested positive for IAV IgM, and 3196 children tested positive for IBV IgM, with an overall positive rate of 28.5 % for IAV and 1.1 % for IBV. IAV infections peaked at 21,502 cases in March 2023. 80,699 children underwent RSV IgM testing from April to October 2023, with 5726 (7.1 %) testing positive. The apex of RSV infections occurred in May 2023, with 2140 cases. Regarding ADV, 100,460 children underwent testing from April to October 2023, with 1981 (11.9 %) testing positive. The pinnacle of ADV infections reached 4546 cases in November 2023. Concerning MP, 474,913 children underwent MP testing, with 73,833 (15.5 %) testing positive. The zenith of MP infections occurred in November 2023, with 25,291 cases. Further analysis revealed that the outbreaks of these pathogens are occurring earlier than in previous years. Additionally, our data showed that children aged >3 years accounted for 79.6 %, 87.8 %, 88.6 %, and 77.8 % of the total IAV-positive, IBV-positive, ADV-positive, and MP-positive children, respectively. Conversely, RSV primarily infected children <6 years.

Conclusion

Various respiratory pathogens showed an epidemic trend in children among children post-COVID-19. These results indicated that we should pay timely attention to the epidemiological trends and characteristics of respiratory pathogens in children after the COVID-19 pandemic and provide relevant information for society and clinical practice.

Establishment and evaluation of MIRA-qPCR assay for the rapid and sensitively detection of Mycoplasma pneumoniae

Aim: Mycoplasma pneumoniae (MP) is a common cause of respiratory infections, and its incidence has increased post-COVID-19 due to "immune debt." Real-time quantitative polymerase chain reaction (qPCR) is the standard for detecting MP, but it has a lengthy detection time. This study aimed to establish a highly sensitive rapid detection method for MP.Materials & methods: We developed an integrated assay combining multienzyme isothermal rapid amplification (MIRA) with qPCR, referred to as MIRA-qPCR, for the rapid detection of MP, delivering results within approximately 40 min.Results: The analytic sensitivity of the MIRA-qPCR assay was 10 copies per reaction, and it exhibited no cross-reactivity with other respiratory pathogens, ensuring high specificity. Clinical sample analysis demonstrated higher sensitivity for MIRA-qPCR compared to qPCR reported in the literature, and 100% concordance with commercial qPCR kit.Conclusion: The MIRA-qPCR method established in this study is a promising tool for the clinical detection of MP, offering significant advantages for the rapid diagnosis of MP infections.

Concomitant Central and Peripheral Nervous System Involvement Associated With Mycoplasma pneumoniae Infection in Pediatric Patients: Two Case Reports and Literature Review

BACKGROUND

Mycoplasma pneumoniae ( M. pneumoniae ) is a common pathogen for community-acquired pneumonia and is also implicated in a broad array of extra-pulmonary manifestations. M. pneumoniae infection is rarely associated with concurrent central nervous system (CNS) and peripheral nervous system (PNS) involvement in children.

METHODS

We report 2 patients who presented with acute encephalitis and polyradiculitis due to M. pneumoniae infection and review the literature to discuss the pathogenesis and treatment of concomitant CNS and PNS involvement associated with M. pneumoniae infection.

RESULTS

We report two 6-year-old boys with M. pneumoniae antecedent infection who presented initially with impaired consciousness followed by limb weakness, limb pain and urinary retention, and responded well to immunotherapy.

CONCLUSIONS

We described 2 patients who presented symptomatic combined CNS and PNS involvement with persistent urinary retention associated with M. pneumoniae infection. We found autoimmunity plays an important role and recommend that antibiotics and immunomodulators should be administered with concurrent CNS and PNS involvement associated with M. pneumoniae .

Research of recombinant influenza A virus as a vector for Mycoplasma pneumoniae P1a and P30a

BACKGROUND

Mycoplasma pneumoniae (MP) is a common respiratory pathogen affecting the longevity of the elderly and the health of children. However, the human vaccine against MP has not been successfully developed till now due to the poor immunogenicity and side effects of MP inactivated or attenuated vaccine. Therefore, it is necessary to develop a MP genetic engineering vaccine with influenza virus strain as vector.

METHODS

In this study, the major antigen genes P1a of MP adhesion factor P1(3862-4554 bases) and P30a of P30(49-822 bases) were inserted into the nonstructural protein (NS) gene of Influenza A virus strain A/Puerto Rio/8/34(H1N1), PR8 for short, to construct the recombinant vectors NS-P1a or NS-P30a. The recombinant pHW2000 plasmids containing NS-P1a or NS-P30a were cotransfected with the rest 7 fragments of PR8 into HEK293T cells. After inoculating chicken embryos, the recombinant influenza viruses rFLU-P1a and rFLU-P30a were rescued. RT-PCR and sequencing were used to identify the recombinant viruses. The hemagglutination titers of rFLU-P1a and rFLU-P30a were determined after five successive generations in chicken embryos so as to indicate the genetic stability of the recombinant viruses. The morphology of recombinant influenza viruses was observed under electron microscopy.

RESULTS

P1a or P30a was designed to be inserted into the modified NS gene sequence separately and synthesized successfully. RT-PCR identification of the recombinant viruses rFLU-P1a and rFLU-P30a showed that P1a (693 bp), P30a (774 bp), NS-P1a (1992bp) and NS-P30a (2073 bp) bands were found, and the sequencing results were correct. After five successive generations, each virus generation has a certain hemagglutination titer (from 1:32 to 1:64), and the band of P1a or P30a can be seen in the corresponding positions. The virus particles under the electron microscope appeared as spheres or long strips connected by several particles, revealing a complete viral membrane structure composed of virus lipid bilayer, hemagglutinin, neuraminidase, and matrix proteins.

CONCLUSION

The recombinant viruses rFLU-P1a and rFLU-P30a which carried the advantaged immune regions of the P1 and P30 genes in MP were successfully constructed and identified. And the genetic stability of rFLU-P1a or rFLU-P30a was relatively high. The typical and complete morphology of influenza virus was observed under the electron microscope. Our research provided a foundation for the further development of MP vaccines for human.

Yinqin Qingfei granules alleviate Mycoplasma pneumoniae pneumonia via inhibiting NLRP3 inflammasome-mediated macrophage pyroptosis

Background

Mycoplasma pneumoniae pneumonia (MPP) is a prevalent respiratory infectious disease in children. Given the increasing resistance of M. pneumoniae (MP) to macrolide antibiotics, the identification of new therapeutic agents is critical. Yinqin Qingfei granules (YQQFG), a Chinese patent medicine formulated specifically for pediatric MPP, lacks a clear explanation of its mechanism.

Methods

The primary components of YQQFG were identified using LC-MS/MS. In vitro, RAW264.7 cells infected with MP underwent morphological examination via scanning electron microscopy. Drug-containing serum was prepared, and its intervention concentration was determined using the CCK-8 assay. The active components of YQQFG were molecularly docked with NLRP3 protein using Autodock Vina software. A RAW264.7 cell line overexpressing NLRP3 was created using lentivirus to pinpoint the target of YQQFG. In vivo, MPP model mice were established via nasal instillation of MP. Lung damage was assessed by lung index and H&E staining. Pyroptosis-associated protein levels in cells and lung tissue were measured by western blot, while interleukin (IL)-1β and IL-18 levels in cell supernatants and mouse serum were quantified using ELISA. Immunofluorescence double staining of lung tissue sections was conducted to assess the correlation between NLRP3 protein expression and macrophages. The expression of the community-acquired respiratory distress syndrome toxin (CARDS TX) was evaluated by qPCR.

Results

25 effective components with favorable oral bioavailability were identified in YQQFG. Both in vitro and in vivo studies demonstrated that YQQFG substantially reduced the expression of the NLRP3/Caspase-1/GSDMD pathway, decreasing the release of IL-1β and IL-18, and inhibited MP exotoxin. Molecular docking indicated strong affinity between most YQQFG components and NLRP3 protein. Lentivirus transfection and immunofluorescence double staining confirmed that YQQFG significantly suppressed NLRP3 expression in macrophages, outperforming azithromycin (AZM). The combination of YQQFG and AZM yielded the optimal therapeutic effect for MPP.

Conclusion

YQQFG mitigates inflammatory responses by suppressing NLRP3 inflammasome-mediated macrophage pyroptosis, thereby ameliorating MP-induced acute lung injury. YQQFG serves as an effective adjunct and alternative medication for pediatric MPP treatment.

An accurate and convenient method for Mycoplasma pneumoniae via one-step LAMP-CRISPR/Cas12b detection platform

Introduction

Mycoplasma pneumoniae (MP) is the major cause of respiratory infections that threaten the health of children and adolescents worldwide. Therefore, an early, simple, and accurate detection approach for MP is critical to prevent outbreaks of MP-induced community-acquired pneumonia.

Methods

Here, we explored a simple and accurate method for MP identification that combines loop-mediated isothermal amplification (LAMP) with the CRISPR/Cas12b assay in a one-pot reaction.

Results

In the current study, the whole reaction was completed within 1 h at a constant temperature of 57°C. The limit of detection of this assay was 33.7 copies per reaction. The specificity of the LAMP-CRISPR/Cas12b method was 100%, without any cross-reactivity with other pathogens. Overall, 272 clinical samples were used to evaluate the clinical performance of LAMP-CRISPR/Cas12b. Compared with the gold standard results from real-time PCR, the present method provided a sensitivity of 88.11% (126/143), specificity of 100% (129/129), and consistency of 93.75% (255/272).

Discussion

Taken together, our preliminary results illustrate that the LAMP-CRISPR/Cas12b method is a simple and reliable tool for MP diagnosis that can be performed in resource-limited regions.

Disease burden and macrolide resistance of Mycoplasma pneumoniae infection in adults in the Asia-Pacific region

OBJECTIVES

In the Asia-Pacific region, Mycoplasma pneumoniae (MP) could be a notable pathogen responsible for adult community-acquired pneumonia (CAP), with varying prevalence rates. This comprehensive review aimed to explore the epidemiology, clinical manifestations, macrolide resistance, and molecular characteristics of MP in adults across several countries in Asia.

METHODS

PubMed, Embase, and Google Scholar were searched for relevant articles from 2010-2023 based on the following keywords: adult and Mycoplasma pneumoniae.

RESULTS

The prevalence of MP in CAP patients in these countries ranged from 2.1% in Korea to 25.5% in Japan. Macrolide resistance was prominent, particularly in China, with rates ranging 26.9-100%. Clinical manifestations of MP infection included protean extrapulmonary manifestations, and complications such as rhabdomyolysis and thrombocytopenia. Molecular characteristics, especially the multiple locus variable-number tandem-repeat analysis type 4/5/7/2, remained predominant across various countries, emphasising the importance of ongoing surveillance.

CONCLUSIONS

This review highlights the urgent need for continued monitoring of MP infections, macrolide resistance, and molecular characteristics to inform effective prevention and treatment strategies in the Asia-Pacific region.

A preliminary prediction model of pediatric Mycoplasma pneumoniae pneumonia based on routine blood parameters by using machine learning method

BACKGROUND

The prevalence and severity of pediatric Mycoplasma pneumoniae pneumonia (MPP) poses a significant threat to the health and lives of children. In this study, we aim to systematically evaluate the value of routine blood parameters in predicting MPP and develop a robust and generalizable ensemble artificial intelligence (AI) model to assist in identifying patients with MPP.

METHODS

We collected 27 features, including routine blood parameters and hs-CRP levels, from patients admitted to The Affiliated Dazu's Hospital of Chongqing Medical University with or without MPP between January, 2023 and January, 2024. A classification model was built using seven machine learning (ML) algorithms to develop an integrated prediction tool for diagnosing MPP. It was evaluated on both an internal validation set (982 individuals) and an external validation set (195 individuals). The primary outcome measured the accuracy of the model in predicting MPP.

RESULTS

The GBDT is state-of-the-art based on 27 features. Following inter-laboratory cohort testing, the GBDT demonstrated an AUC, accuracy, specificity, sensitivity, PPV, NPV, and F1-score of 0.980 (0.938-0.995), 0.928 (0.796-0.970), 0.929 (0.717-1.000), 0.926 (0.889-0.956), 0.922 (0.727-1.000), 0.937 (0.884-0.963), and 0.923 (0.800-0.966) in stratified 10-fold cross-validation. A GBDT-based AI Lab was developed to facilitate the healthcare providers in remote and impoverished areas.

CONCLUSIONS

The GBDT-based AI Lab tool, with high sensitivity and specificity, could help discriminate between pediatric MPP infection and non-MPP infection based on routine blood parameters. Moreover, a user-friendly webpage tool for AI Lab could facilitate healthcare providers in remote and impoverished areas where advanced technologies are not accessible.

Coinfection of viruses in children with community-acquired pneumonia

BACKGROUND

Virus, particularly respiratory tract virus infection is likely to co-occur in children with community-acquired pneumonia (CAP). Study focusing on the association between common viruses coinfection and children with CAP is rare. We aimed to study the association between seven common viruses coinfection and clinical/laboratory indexes in children with CAP.

METHODS

Six hundred and eighty-four CAP cases from our hospital were enrolled retrospectively. Seven common viruses, including influenza A (FluA), influenza B (FluB), human parainfluenza virus (HPIV), Esptein-Barr virus (EBV), coxsackie virus (CoxsV), cytomegalovirus (CMV), and herpes simplex virus (HSV) were investigated for their associations with CAP. We analyzed the differences of hospitalization days, white blood cell (WBC), c-reactive protein (CRP), platelet (PLT), erythrocyte sedimentation rate (ESR), procalcitonin (PCT), urine red blood cell (uRBC), blood urea nitrogen (BUN), serum creatinine (Scr), alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine kinase (CK) and creatine kinase isoenzyme (CKMB) among different viruses coinfection groups by using one-way ANOVA analysis. The differences of clinical/laboratory indexes between ordinary and severe pneumonia groups, as well as non-virus vs multi co-infection viruses groups, and single vs multi co-infection viruses groups by using independent samples T test. Receiver operating characteristic (ROC) curve analyses were applied to test the the predictive value of the clinical/laboratory parameters for the risk of viruses coinfections among CAP. Binary logistic analysis was performed to test the association between various indexes and viruses co-infection.

RESULTS

Eighty-four multiple viruses coinfections yielded different prognosis compared with that in 220 single virus coinfection. CMV coinfection was associated with longest hospitalization days, highest ALT, AST and CKMB level. HSV coinfection was associated with highest WBC count, CRP, ESR, and BUN. EBV coinfection was associated with highest PLT and PCT level. FluB coinfection was associated with highest Scr level. CoxsV coinfection was associated with highest uRBC, LDH and CK level. ROC curve analyses showed that CK had the largest area under the curve (AUC: 0.672, p < 10-4) for the risk of viruses coinfections risk in CAP. Significant association between PLT, uRBC, BUN, CK, and CKMB and virus coinfection risk in CAP was observed.

CONCLUSIONS

Multiple viruses coinfections indicated different prognosis. Different viruses coinfection yielded varying degrees of effects on the cardiac, liver, kidney and inflamatory injury in CAP. The alterations of clinical/laboratory parameters, particularly CK may be associated with the risk of viruses coinfections in CAP.

Azithromycin Effectiveness in Children with Mutated Mycoplasma Pneumoniae Pneumonia

Objective

Mycoplasma pneumoniae (MP) is highly resistant to macrolides in China. However, macrolides still exhibit clinical effectiveness in some macrolide-resistant patients. We tend to explore azithromycin effectiveness in Mycoplasma pneumoniae pneumonia (MPP) children with A2063/2064G mutation.

Methods

This retrospective observational cohort study was conducted at the Children's Hospital of the Chongqing Medical University. Children with macrolide-resistant mutations (A2063/2064G) diagnosed as MPP were retrospectively enrolled. Receiver operating characteristic (ROC) curves and logistic regression analysis were used to evaluate and identify independent risk factors for treatment failure (progress to refractory Mycoplasma pneumoniae pneumonia [RMPP]) in macrolide-unresponsive Mycoplasma pneumoniae pneumonia (MUMPP) children with the A2063/2064G mutation.

Results

One hundred fifty-five children were retrospectively enrolled. More than 20% (36/155, 23.23%) of patients experienced defervescence within 3 days of azithromycin treatment. RMPP was diagnosed in 54 patients (54/155, 34.84%) and the incidence of RMPP during hospitalization was 22.72 per 1000 person-days. Logistic regression analysis showed that lactate dehydrogenase (LDH) ≥ 399 (U/L) was an independent risk factor for RMPP (odds ratio [OR] 4.66, 95% confidence interval [CI] 1.31-17.10, P=0.017). During the year followed, RMPP patients had a significantly higher incidence of bronchiolitis obliterans and bronchiectasis than non-RMPP patients (16.67% vs 1.98%, P=0.001; 9.26% vs 0.00%, P=0.005, respectively).

Conclusion

Azithromycin was effective in children with MPP with the A2063/2064G mutation. For MUMPP children with A2063/2064G mutation, children with LDH ≥ 399 (U/L) had significant higher risk for progression to RMPP, and should consider to be treated with alternative antibiotics (eg tetracyclines, and fluoroquinolones).

Design of a novel multiepitope vaccine with CTLA-4 extracellular domain against Mycoplasma pneumoniae: A vaccine-immunoinformatics approach

BACKGROUND

Community-acquired pneumonia often stems from the macrolide-resistant strain of Mycoplasma pneumoniae, yet no effective vaccine exists against it.

METHODS

This study proposes a vaccine-immunoinformatics strategy for Mycoplasma pneumoniae and other pathogenic microbes. Specifically, dominant B and T cell epitopes of the Mycoplasma pneumoniae P30 adhesion protein were identified through immunoinformatics method. The vaccine sequence was then constructed by coupling with CTLA-4 extracellular region, a novel molecular adjuvant for antigen-presenting cells. Subsequently, the vaccine's physicochemical properties, antigenicity, and allergenicity were verified. Molecular dynamics modeling was employed to confirm interaction with TLR-2, TLR-4, B7-1, and B7-2. Finally, the vaccine underwent in silico cloning for expression.

RESULTS

The vaccine exhibited both antigenicity and non-allergenicity. Molecular dynamics simulation, post-docking with TLR-2, TLR-4, B7-1, and B7-2, demonstrated stable interaction between the vaccine and these molecules. In silico cloning confirmed effective expression of the vaccine gene in insect baculovirus vectors.

CONCLUSION

This vaccine-immunoinformatics approach holds promise for the development of vaccines against Mycoplasma pneumoniae and other pathogenic non-viral and non-bacterial microbes.

Exploring the pathogenetic mechanisms of Mycoplasmapneumoniae (Review)

Mycoplasmas, the smallest self-replicating prokaryotes without a cell wall, are the most prevalent and extensively studied species in humans. They significantly contribute to chronic respiratory tract illnesses and pneumonia, with children and adolescents being particularly vulnerable. Mycoplasma pneumoniae (M. pneumoniae) infections typically tend to be self-limiting and mild but can progress to severe or even life-threatening conditions in certain individuals. Extrapulmonary effects often occur without pneumonia, and both intrapulmonary and extrapulmonary complications operate through separate pathological mechanisms. The indirect immune-mediated damage of the immune system, vascular blockages brought on by vasculitis or thrombosis and direct harm from invasion or locally induced inflammatory cytokines are potential causes of extrapulmonary manifestations due to M. pneumoniae. Proteins associated with adhesion serve as the primary factor crucial for the pathogenicity of M. pneumoniae, relying on a specialized polarized terminal attachment organelle. The type and density of these host receptors significantly impact the adhesion and movement of M. pneumoniae, subsequently influencing the pathogenic mechanism and infection outcomes. Adjacent proteins are crucial for the proper assembly of the attachment organelle, with variations in the genetic domains of P1, P40 and P90 surfaces contributing to the variability of clinical symptoms and offering new avenues for developing vaccines against M. pneumoniae infections. M. pneumoniae causes oxidative stress within respiratory tract epithelial cells by adhering to host cells and releasing hydrogen peroxide and superoxide radicals. This oxidative stress enhances the vulnerability of host cells to harm induced by oxygen molecules. The lack of superoxide dismutase and catalase of bacteria allows it to hinder the catalase activity of the host cell, leading to the reduced breakdown of peroxides. Lung macrophages play a significant role in managing M. pneumoniae infection, identifying it via Toll-like receptor 2 and initiating the myeloid differentiation primary response gene 88-nuclear factor κΒ signaling cascade. However, the precise mechanisms enabling M. pneumoniae to evade intracellular host defenses remain unknown, necessitating further exploration of the pathways involved in intracellular survival. The present comprehensive review delves into the pathogenesis of M. pneumoniae infection within the pulmonary system and into extrapulmonary areas, outlining its impact.

Study on the Correlation Between the Expression of NF-Ƙb in the Alveolar Lavage Fluid of Children with Severe Mycoplasma Pneumoniae Pneumonia, Its Clinical Characteristics, and Cellular Immunity

Objective

This study explored the level of nuclear factor-ƙB (NF-ƙB) in the bronchoalveolar lavage fluid (BALF) of children with severe Mycoplasma Pneumoniae pneumonia (SMPP) and the correlation between NF-ƙB, cellular immunity, and clinical characteristics.

Methods

A total of 41 hospitalized children diagnosed with SMPP were selected and included in the SMPP group, and 13 bronchial foreign bodies (FB) without infection during the same period were included in the FB group. The NF-ƙB in the BALF of participants was detected by enzyme-linked immunosorbent assay. The correlation between NF-ƙB and laboratory findings, cellular immunity, and the clinical features in children with SMPP was analyzed. The differences in chest imaging and bronchoscopy in children with SMPP were observed.

Results

The levels of NF-ƙB were significantly increased in the SMPP group compared with the FB group (P < 0.001). There were correlations between different NF-ƙB pairs in the SMPP group (P < 0.01). Nuclear factor-ƙB (NF-ƙB) correlated with IL-6, the mycoplasma load in BALF, fever peak, length of hospital stay, and sputum suppository (P < 0.05). The higher the intracellular NF-ƙB level in BALF, the lower the CD3+ CD4+ value in peripheral blood (P < 0.05). Intracellular NF-ƙB and total NF-ƙB correlated with pleural effusion, pericardial effusion, and extrapulmonary complications (P < 0.05).

Conclusion

NF-ƙB is involved in airway inflammation changes in children with SMPP. The higher the level of NF-ƙB in the airway, the more severe the clinical manifestations, and the longer the length of hospital stay is likely to be.

Marine-Derived Sulfated Glycans Inhibit the Interaction of Heparin with Adhesion Proteins of Mycoplasma pneumoniae

Mycoplasma pneumoniae, a notable pathogen behind respiratory infections, employs specialized proteins to adhere to the respiratory epithelium, an essential process for initiating infection. The role of glycosaminoglycans, especially heparan sulfate, is critical in facilitating pathogen-host interactions, presenting a strategic target for therapeutic intervention. In this study, we assembled a glycan library comprising heparin, its oligosaccharide derivatives, and a variety of marine-derived sulfated glycans to screen the potential inhibitors for the pathogen-host interactions. By using Surface Plasmon Resonance spectroscopy, we evaluated the library's efficacy in inhibiting the interaction between M. pneumoniae adhesion proteins and heparin. Our findings offer a promising avenue for developing novel therapeutic strategies against M. pneumoniae infections.

Childhood Mycoplasma pneumoniae: epidemiology and manifestation in Northeast and Inner Mongolia, China

Mycoplasma pneumoniae (MP) is commonly detected in children. However, the epidemiological trends of MP in Northeast (NE) China are unclear. This retrospective study aimed to investigate the prevalence of MP infections in this understudied region. The clinical manifestations and bronchoscopic findings observed in hospitalized patients with severe Mycoplasma pneumoniae pneumonia (SMPP) were collected from comprehensive data obtained from six tertiary hospitals in NE and Inner Mongolian (IM) China, from 1 January 2017 to 31 December 2023. A total of 5,593,530 children who visited the outpatient and emergency departments, and 412,480 inpatient hospitalized children were included in the study. The positivity rate of MP immunoglobulin M (IgM) in the children who visited the outpatient and emergency departments varied from 7.80% to 10.12%, whereas that of MP infection in hospitalized children ranged from 27.18% to 30.10%. Children hospitalized for MP infection were mainly concentrated in the 1- to 4-year (41.39%) and 4- to 7-year (24.25%) age groups. Before 2020, the season with the highest incidence of MP was winter. After the implementation of non-pharmaceutical interventions (NPIs), the MP epidemic season changed, and the number of children with MP infections decreased; however, the proportion of MP infections in hospitalized children did not change significantly. Starting from August 2023, the MP infection rate in outpatient, emergency, and hospitalized children increased sharply, with SMPP and its complications (e.g., plastic bronchitis and pleural effusion) increasing significantly. MP is prevalent in NE and IM, China. When the NPIs ended, MP infection showed a delayed outbreak trend, and the number of children with severe infection increased significantly.

IMPORTANCE

In Northeastern (NE) and Inner Mongolia (IM), the incidence of Mycoplasma pneumoniae (MP) infections, including severe Mycoplasma pneumoniae pneumonia (SMPP), is high, posing health risks and imposing substantial economic burdens on the local population. Therefore, it is imperative to prioritize the study of MP prevalence and address the research gaps in MP epidemiology in these areas of China. We obtained a comprehensive collection of pediatric outpatient, emergency, and inpatient data from six public Grade III hospitals. We believe that our study makes a significant contribution to the literature because understanding regional variations in MP infections can help healthcare professionals tailor prevention and treatment strategies, and studying bronchoscopic manifestations can provide insights into the impact of the disease on the respiratory system, potentially leading to a more effective clinical management.

Intracardiac and Cerebral Thrombosis Complicated With Mycoplasma Pneumonia

A seven-year-old girl developed multiposition thrombosis after fever and respiratory symptoms. Chest computed tomography (CT) scan demonstrated bilateral infiltrates, consolidation of the right lower lobe, and pleural effusion in the right lung field. Brain magnetic resonance imaging (MRI) showed multiple abnormal signals in the brain with limited diffusion, and cerebral infarction could not be excluded. Echocardiography revealed hypoechoic mitral valve tips, which are likely to be suspected as vegetation. Mycoplasma pneumoniae infection was clarified by a four-fold increase in IgG antibodies to M. pneumoniae sera. D-dimer levels were elevated increasingly. We found and reported this rare pediatric case of an M. pneumoniae-induced severe pneumonia complicated with intracardiac and cerebral thrombosis. We investigate the clinical characteristics, diagnosis, and treatment of refractory mycoplasma pneumonia complicated with intracardiac and cerebral thrombosis in children.

Insights into the defensive roles of lncRNAs during Mycoplasma pneumoniae infection

Mycoplasma pneumoniae causes respiratory tract infections, affecting both children and adults, with varying degrees of severity ranging from mild to life-threatening. In recent years, a new class of regulatory RNAs called long non-coding RNAs (lncRNAs) has been discovered to play crucial roles in regulating gene expression in the host. Research on lncRNAs has greatly expanded our understanding of cellular functions involving RNAs, and it has significantly increased the range of functions of lncRNAs. In lung cancer, transcripts associated with lncRNAs have been identified as regulators of airway and lung inflammation in a process involving protein complexes. An excessive immune response and antibacterial immunity are closely linked to the pathogenesis of M. pneumoniae. The relationship between lncRNAs and M. pneumoniae infection largely involves lncRNAs that participate in antibacterial immunity. This comprehensive review aimed to examine the dysregulation of lncRNAs during M. pneumoniae infection, highlighting the latest advancements in our understanding of the biological functions and molecular mechanisms of lncRNAs in the context of M. pneumoniae infection and indicating avenues for investigating lncRNAs-related therapeutic targets.

The Clinical Value of Systemic Immune Inflammation Index (SII) in Predicting the Severity of Hospitalized Children with Mycoplasma Pneumoniae Pneumonia: A Retrospective Study

Objective

The Systemic Immune Inflammation Index (SII), as a novel inflammation biomarker that comprehensively reflects the inflammatory and immune status of the body, has not been reported in studies on Mycoplasma pneumoniae pneumonia (MPP) in children. This study aims to investigate whether SII can serve as an effective indicator for evaluating the condition of MPP.

Methods

This study recruited a total of 304 hospitalized patients with mycoplasma pneumoniae pneumonia (MPP), including 78 patients with severe MPP (SMPP) and 226 patients with non-SMPP. Univariate analysis using chi-square test, t-test, and Mann-Whitney U-test was conducted to analyze the clinical data of the patients. Logistic regression analysis was employed to identify the main risk factors for SMPP. Receiver operating characteristic curves were plotted to evaluate the potential of using neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), and systemic immune response index (SIRI) to predict the severity of MPP.

Results

The ROC curve results show that patients with SII values ≥ 699.00 are more likely to develop severe MPP (sensitivity=0.876, specificity=0.987, AUC=0.940), and the predictive value of SII is significantly better than that of NLR, PLR, and SIRI. The results of multivariate logistic regression analysis indicate that SII can serve as a major risk factor for distinguishing non-SMPP from SMPP.

Conclusion

This study suggests that SII may be an effective indicator for predicting the severity of MPP in children. SII is more sensitive and specific than NLR, PLR, and SIRI in evaluating the condition of MPP.

Association between Mycoplasma pneumoniae infection, high‑density lipoprotein metabolism and cardiovascular health (Review)

The association between Mycoplasma pneumoniae (M. pneumoniae) infection, high-density lipoprotein metabolism and cardiovascular disease is an emerging research area. The present review summarizes the basic characteristics of M. pneumoniae infection and its association with high-density lipoprotein and cardiovascular health. M. pneumoniae primarily invades the respiratory tract and damages the cardiovascular system through various mechanisms including adhesion, invasion, secretion of metabolites, production of autoantibodies and stimulation of cytokine production. Additionally, the present review highlights the potential role of high-density lipoprotein for the development of prevention and intervention of M. pneumoniae infection and cardiovascular disease, and provides suggestions for future research directions and clinical practice. It is urgent to explore the specific mechanisms underlying the association between M. pneumoniae infection, high-density lipoprotein metabolism, and cardiovascular disease and analyze the roles of the immune system and inflammatory response.

Mycoplasma agalactiae Vaccines: Current Status, Hurdles, and Opportunities Due to Advances in Pathogenicity Studies

Contagious agalactia (CA) is a serious multietiological disease whose classic etiological agent is Mycoplasma agalactiae and which causes high morbidity and mortality rates in infected herds. CA is classified as a notifiable disease by the World Organization for Animal Health due to its significant worldwide economic impact on livestock, primarily involving goat and sheep farms. The emergence of atypical symptoms and strains of M. agalactiae in wildlife ungulates reestablishes its highly plastic genome and is also of great epidemiological significance. Antimicrobial therapy is the main form of control, although several factors, such as intrinsic antibiotic resistance and the selection of resistant strains, must be considered. Available vaccines are few and mostly inefficient. The virulence and pathogenicity mechanisms of M. agalactiae mainly rely on surface molecules that have direct contact with the host. Because of this, they are essential for the development of vaccines. This review highlights the currently available vaccines and their limitations and the development of new vaccine possibilities, especially considering the challenge of antigenic variation and dynamic genome in this microorganism.

In vitro pharmacodynamics of nemonoxacin and other antimicrobial agents against Mycoplasma pneumoniae

IMPORTANCE

This study first reported the in vitro effector kinetics of the new non-fluorinated quinolone, nemonoxacin, against macrolide-resistant M. pneumoniae (MRMP) and macrolide susceptible M. pneumoniae (MSMP) strains along with other antimicrobial agents. The time-kill assays and pharmacodynamic analysis showed that nemonoxacin has significant mycoplasmacidal activity against MRMP and MSMP. This study paves the road to establish appropriate dosing protocols of a new antimicrobial drug for children infected with M. pneumoniae.

Global research trends of Mycoplasma pneumoniae pneumonia in children: a bibliometric analysis

BACKGROUND

Mycoplasma pneumoniae pneumonia (MPP), attributable to Mycoplasma pneumoniae (MP), represents a predominant form of community-acquired pneumonia in pediatric populations, thereby posing a significant threat to pediatric health. Given the burgeoning volume of research literature associated with pediatric MPP in recent years, it becomes imperative to undertake a bibliometric analysis aimed at delineating the current research landscape and emerging trends, thereby furnishing a framework for subsequent investigations.

METHODS

A comprehensive literature search targeting pediatric MPP was conducted in the Web of Science Core Collection. After the removal of duplicate entries through Endnote software, the remaining articles were subject to scientometric analysis via Citespace software, VOSviewer software and R language, focusing on variables such as publication volume, contributing nations, institutions and authors, references and keywords.

RESULTS

A total of 1,729 articles pertinent to pediatric MPP were included in the analysis. China and the United States emerged as the nations with the highest publication output. Italian scholar Susanna Esposito and Japanese scholar Kazunobu Ouchi were the most influential authors in the domain of pediatric MPP. Highly-cited articles primarily focused on the epidemiological investigation of pediatric MPP, the clinical characteristics and treatment of macrolide-resistant MPP, and biomarkers for refractory Mycoplasma pneumoniae pneumonia (RMPP). From the corpus of 1,729 articles, 636 keywords were extracted and categorized into ten clusters: Cluster #0 centered on molecular-level typing of macrolide-resistant strains; Cluster #1 focused on lower respiratory tract co-infections; Clusters #2 and #6 emphasized other respiratory ailments caused by MP; Cluster #3 involved biomarkers and treatment of RMPP; Clusters #4 and #9 pertained to extrapulmonary complications of MPP, Clusters #5 and #7 addressed etiological diagnosis of MPP, and Cluster #8 explored pathogenic mechanisms.

CONCLUSIONS

The past few years have witnessed extensive attention directed towards pediatric MPP. Research in pediatric MPP principally revolves around diagnostic techniques for MP, macrolide resistance, complications of MPP, treatment and diagnosis of RMPP, and elucidation of pathogenic mechanisms. The present study provides pediatric clinicians and researchers with the research status and focal points in this field, thereby guiding the orientation of future research endeavors.

[Construction of a predictive model for performing bronchoalveolar lavage in children with Mycoplasma pneumoniae pneumonia and pulmonary consolidation]

OBJECTIVES

To investigate the risk factors for performing bronchoalveolar lavage (BAL) in children with Mycoplasma pneumoniae pneumonia (MPP) and pulmonary consolidation, and to construct a predictive model for performing BAL in these children.

METHODS

A retrospective analysis was performed for the clinical data of 202 children with MPP who were hospitalized in the Department of Pediatrics, Changzhou No. 2 People's Hospital Affiliated to Nanjing Medical University, from August 2019 to September 2022. According to whether BAL was performed, they were divided into BAL group with 100 children and non-BAL group with 102 children. A multivariate logistic regression analysis was used to identify the risk factors for performing BAL in MPP children with pulmonary consolidation. Rstudio software (R4.2.3) was used to establish a predictive model for performing BAL, and the receiver operator characteristic (ROC) curve, C-index, and calibration curve were used to assess the predictive performance of the model.

RESULTS

The multivariate logistic regression analysis demonstrated that the fever duration, C-reactive protein levels, D-dimer levels, and presence of pleural effusion were risk factors for performing BAL in MPP children with pulmonary consolidation (P<0.05). A nomogram predictive model was established based on the results of the multivariate logistic regression analysis. In the training set, this model had an area under the ROC curve of 0.915 (95%CI: 0.827-0.938), with a sensitivity of 0.826 and a specificity of 0.875, while in the validation set, it had an area under the ROC curve of 0.983 (95%CI: 0.912-0.996), with a sensitivity of 0.879 and a specificity of 1.000. The Bootstrap-corrected C-index was 0.952 (95%CI: 0.901-0.986), and the calibration curve demonstrated good consistency between the predicted probability of the model and the actual probability of occurrence.

CONCLUSIONS

The predictive model established in this study can be used to assess the likelihood of performing BAL in MPP children with pulmonary consolidation, based on factors such as fever duration, C-reactive protein levels, D-dimer levels, and the presence of pleural effusion. Additionally, the model demonstrates good predictive performance.

Total Flavonoids from Camellia oleifera Alleviated Mycoplasma pneumoniae-Induced Lung Injury via Inhibition of the TLR2-Mediated NF-κB and MAPK Pathways

Mycoplasma pneumoniae (M. pneumoniae) is an atypical bacterial pathogen responsible for community-acquired pneumonia primarily among school-aged children and young adults. Camellia oleifera (C. oleifera) has been used as a medicinal and edible plant in China for centuries, the constituents from which possessed various bioactivities. Notably, flavonoids existing in residues of C. oleifera defatted seeds exhibited significant anti-inflammatory activities. In the present study, we investigated the impact of total flavonoids from C. oleifera (TFCO) seed extract on M. pneumoniae pneumonia. TFCO was obtained using multiple column chromatography methods and identified as kaempferol glycosides via UPLC-HRESIMS. In a M. pneumoniae pneumonia mouse model, TFCO significantly reduced the lung damage, suppressed IL-1β, IL-6, and TNF-α production, and curbed TLR2 activation triggered by M. pneumoniae. Similarly, in RAW264.7 macrophage cells stimulated by lipid-associated membrane proteins (LAMPs), TFCO suppressed the generation of proinflammatory cytokines and TLR2 expression. Moreover, TFCO diminished the phosphorylation of IκBα, JNK, ERK, p38, and p65 nuclear translocation in vitro. In conclusion, TFCO alleviated M. pneumoniae-induced lung damage via inhibition of TLR2-mediated NF-κB and MAPK pathways, suggesting its potential therapeutic application in M. pneumoniae-triggered lung inflammation.

Overlapping clinical presentation of Mycoplasma-induced rash and mucositis and drug-induced Stevens Johnson Syndrome: A case report

Introduction

Mycoplasma pneumoniae is a worldwide occurring common bacterial agent for community-acquired pneumonia especially in children and young people with high contagiousness. Extrapulmonary complications such as cardiopulmonary, gastrointestinal, neurological and mucocutaneous manifestations including Mycoplasma pneumoniae-induced rash and mucositis (MIRM) may occur especially in adults. MIRM is an important differential diagnosis of Stevens Johnson Syndrome (SJS). Both clinically present similar as mucocutaneous erosive eruptions but have different etiologies.

Case presentation

We present an atypical case of a 36-year-old female with overlapping clinical features of MIRM and SJS. The patient presented to our allergy-outpatient clinic after recovering from mucocutaneous erosive eruptions and receiving an allergy-passport upon discharge for all drugs administered during the course of treatment including a subsequent ban of all beta-lactam antibiotics and NSAIDs for the future resulting in a desperate patient and treating physicians. A positive result of Mycoplasma pneumoniae in the sputum culture upon discharge was unnoticed. An allergological work-up with skin testing and drug provocation testing with the culprit drugs and safe alternatives was performed which resulted negative. Therefore, a new allergy passport was issued with drug alternatives that the patient may use in the future. A diagnosis of MIRM was subsequently made.

Discussion

The present case report depicts the diagnostic algorithm in an atypical case with overlapping clinical features of a MIRM and SJS.

Conclusion

Patients with atypical mucocutaneous eruptions of possible allergological etiology should receive a careful allergological work-up in an experienced tertiary referral center to reduce the number of inadequate allergy passport distribution.

The Impact of CC16 on Pulmonary Epithelial-Driven Host Responses during Mycoplasma pneumoniae Infection in Mouse Tracheal Epithelial Cells

Club Cell Secretory Protein (CC16) plays many protective roles within the lung; however, the complete biological functions, especially regarding the pulmonary epithelium during infection, remain undefined. We have previously shown that CC16-deficient (CC16-/-) mouse tracheal epithelial cells (MTECs) have enhanced Mp burden compared to CC16-sufficient (WT) MTECs; therefore, in this study, we wanted to further define how the pulmonary epithelium responds to infection in the context of CC16 deficiency. Using mass spectrometry and quantitative proteomics to analyze proteins secreted apically from MTECs grown at an air-liquid interface, we investigated the protective effects that CC16 elicits within the pulmonary epithelium during Mycoplasma pneumoniae (Mp) infection. When challenged with Mp, WT MTECs have an overall reduction in apical protein secretion, whereas CC16-/- MTECs have increased apical protein secretion compared to their unchallenged controls. Following Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) assessment, many of the proteins upregulated from CC16-/- MTECS (unchallenged and during Mp infection) were related to airway remodeling, which were not observed by WT MTECs. These findings suggest that CC16 may be important in providing protection within the pulmonary epithelium during respiratory infection with Mp, which is the major causative agent of community-acquired pneumoniae.

miRNA, lncRNA and circRNA: targeted molecules with therapeutic promises in Mycoplasma pneumoniae infection

Mycoplasma pneumoniae (MP) is primarily recognized as a respiratory pathogen that causes community-acquired pneumonia, which can lead to acute upper and lower airway inflammation and extrapulmonary syndrome. Refractory pneumonia caused by MP can cause severe complications and even be life-threatening, particularly in infants and the elderly. It is well-known that non-coding RNAs (ncRNAs) represented by miRNAs, lncRNAs and circRNAs have been manifested to be widely involved in the regulation of gene expression. Growing evidence indicates that these ncRNAs have distinct differentiated expression in MP infection and affect multiple biological processes, playing an indispensable role in the initiation and promotion of MP infection. However, the epigenetic mechanisms involved in the development of MP infection remain unclear. This article reviews the mechanisms by which miRNAs, lncRNAs, and circRNAs mediate MP infection, such as inflammatory responses, apoptosis and pulmonary fibrosis. Focusing on miRNAs, lncRNAs and circRNAs associated with MP infection could provide new insights into this disease's early diagnosis and therapeutic approaches.

Acetylcysteine and budesonide for the treatment of refractory Mycoplasma pneumoniae pneumonia in children: a clinical observation

BACKGROUND

To examine the clinical impact of bronchoscope alveolar lavage (BAL) combination with budesonide, ambroxol + budesonide, or acetylcysteine + budesonide in the treatment of refractory Mycoplasma pneumoniae pneumonia (RMPP).

METHODS

Eighty-two RMPP patients admitted to Pediatrics at The First People's Hospital of Zhengzhou were retrospectively evaluated between August 2016 and August 2019. All patients were administered BAL in addition to intravenous Azithromycin, expectoration, and nebulizer inhalation. The medications added to the BLA separated the patients into the Budesonide group, Ambroxol + budesonide group, and acetylcysteine + budesonide group. Analyzed were the variations in laboratory examination indices, improvement in lung imaging, overall effective rate, and adverse responses in the three groups.

RESULTS

The laboratory test indices of patients in all three groups improved significantly relative to pre-treatment levels, and the results were statistically significant. After therapy, there were no significant differences between the three groups in terms of white blood cell (WBC), C-reactive protein (CRP), or erythrocyte sedimentation rate (ESR). Serum lactate dehydrogenase (LDH) and serum ferritin (SF) varied significantly across the three groups (P < 0.05). In the acetylcysteine + budesonide group, the absorption rate of lung imaging lesions and clinical efficacy were superior to those of the other two groups. There were no significant differences between the three groups in the occurrence of adverse events (P > 0.05).

CONCLUSIONS

BLA-coupled acetylcysteine + budesonide was superior to the other two groups in enhancing the effectiveness of RMPP in children, which might increase lung opacity absorption and minimize lung inflammation.

Extracellular Vesicles Released from Macrophages Infected with Mycoplasma pneumoniae Stimulate Proinflammatory Response via the TLR2-NF-κB/JNK Signaling Pathway

Mycoplasma pneumoniae (M. pneumoniae, Mp) is an intracellular pathogen that causes pneumonia, tracheobronchitis, pharyngitis, and asthma in humans and can infect and survive in the host cells leading to excessive immune responses. Extracellular vesicles (EVs) from host cells carry components of pathogens to recipient cells and play a role in intercellular communication during infection. However, there is limited knowledge on whether EVs derived from M. pneumoniae-infected macrophages play as intercellular messengers and functional mechanisms. In this study, we establish a cell model of M. pneumoniae-infected macrophages that continuously secrete EVs to further asses their role as intercellular messengers and their functional mechanisms. Based on this model, we determined a method for isolating the pure EVs from M. pneumoniae-infected macrophages, which employs a sequence of operations, including differential centrifugation, filtering, and ultracentrifugation. We identified EVs and their purity using multiple methods, including electron microscopy, nanoparticle tracking analysis, Western blot, bacteria culture, and nucleic acid detection. EVs from M. pneumoniae-infected macrophages are pure, with a 30-200 nm diameter. These EVs can be taken up by uninfected macrophages and induce the production of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-8 through the nuclear factor (NF)-κB, and mitogen-activated protein kinases (MAPK) signals pathway. Moreover, the expression of inflammatory cytokines induced by EVs relies on TLR2-NF-κB/JNK signal pathways. These findings will help us better understand a persistent inflammatory response and cell-to-cell immune modulation in the context of M. pneumoniae infection.

The rapid diagnosis of Mycoplasma pneumonia using in situ hybridization on clinical samples

The microbiological etiology of seasonal upper respiratory illnesses in the United States is dominated by viruses, including influenza A, B, respiratory syncytial virus, and SARS-CoV2. Mycoplasma pneumonia, treatable with antibiotics, can also cause upper respiratory symptoms and is typically associated with about 15 % of cases. There is no clinical or radiologic finding diagnostic of Mycoplasma pneumonia infection and PCR-based testing is not routinely used in the clinical setting. Further, the bacteria grows slowly in culture and the diagnostic IgM response will take days after the onset of infection. Thus, a rapid diagnostic test for Mycobacterium pneumonia infection is needed. This study documented two cases of Mycoplasma pneumonia infection of the upper respiratory system using in situ hybridization in a series of over 20 patients who were being tested for SARS-CoV2 infection. The respiratory secretions were placed on a glass slide, fixed in 10 % buffered formalin, and then tested using a Mycoplasma pneumonia probe. The high bacterial number associated with acute infection allowed for straightforward detection by in situ hybridization in a few hours. Antibiotic therapy led to rapid resolution of the symptoms. This highlights the ability of standard in situ hybridization as a rapid diagnostic test for Mycoplasma pneumonia in the clinical setting.

Essential protein P116 extracts cholesterol and other indispensable lipids for Mycoplasmas

Mycoplasma pneumoniae, responsible for approximately 30% of community-acquired human pneumonia, needs to extract lipids from the host environment for survival and proliferation. Here, we report a comprehensive structural and functional analysis of the previously uncharacterized protein P116 (MPN_213). Single-particle cryo-electron microscopy of P116 reveals a homodimer presenting a previously unseen fold, forming a huge hydrophobic cavity, which is fully accessible to solvent. Lipidomics analysis shows that P116 specifically extracts lipids such as phosphatidylcholine, sphingomyelin and cholesterol. Structures of different conformational states reveal the mechanism by which lipids are extracted. This finding immediately suggests a way to control Mycoplasma infection by interfering with lipid uptake.

Infection, Transmission, Pathogenesis and Vaccine Development against Mycoplasma gallisepticum

Mycoplasma sp. comprises cell wall-less bacteria with reduced genome size and can infect mammals, reptiles, birds, and plants. Avian mycoplasmosis, particularly in chickens, is primarily caused by Mycoplasma gallisepticum (MG) and Mycoplasma synoviae. It causes infection and pathology mainly in the respiratory, reproductive, and musculoskeletal systems. MG is the most widely distributed pathogenic avian mycoplasma with a wide range of host susceptibility and virulence. MG is transmitted both by horizontal and vertical routes. MG infection induces innate, cellular, mucosal, and adaptive immune responses in the host. Macrophages aid in phagocytosis and clearance, and B and T cells play critical roles in the clearance and prevention of MG. The virulent factors of MG are adhesion proteins, lipoproteins, heat shock proteins, and antigenic variation proteins, all of which play pivotal roles in host cell entry and pathogenesis. Prevention of MG relies on farm and flock biosecurity, management strategies, early diagnosis, use of antimicrobials, and vaccination. This review summarizes the vital pathogenic mechanisms underlying MG infection and recapitulates the virulence factors of MG-host cell adhesion, antigenic variation, nutrient transport, and immune evasion. The review also highlights the limitations of current vaccines and the development of innovative future vaccines against MG.

The role of serum inflammatory in mycoplasma pneumonia infection with respiratory asthma

OBJECTIVE

With the growing frequency of Mycoplasma pneumoniae infections linked to respiratory asthma (MP-RA), particularly in children, the quest for novel diagnostic molecular markers has become critical. We examined the link between serum immunoglobulin, inflammatory variables, vitamin A, and vitamin D levels in MP-RA patients and then found markedly diagnostic indicators.

METHODS

From January 2015 to March 2020, our hospital screened 55 cases of healthy control children (HC), 53 instances of mycoplasma pneumonia infection complicated with respiratory asthma (MP-RA), and 58 cases of non-respiratory asthma children for pneumonia mycoplasma infection (MP). Serum immunoglobulins, inflammatory markers, vitamin D, and vitamin A levels were analyzed, and a predictive model including the feature chosen in the least absolute shrinkage and selection operator regression model was developed.

RESULTS

Serum TNF- and IL-1b levels were greater in MP-RA children than in MP children, but 25(OH)D, IgG, and IgA levels were lower. Our findings verified the link between IgA, TNF-a, 25(OH)D, and vitamin A with MP-RA. In addition, TNF-a, IL-1b, 25(OH)D (Vit-D), IgG, and IgA were the predictors in the prediction nomogram, showing the combined influence of serum inflammation in MP-RA. C-index of 0.985 (95% CI: -1.25 to 1.68) shows high scaling ability and the model exhibits good discriminative capacity. With range validation, the high C-index value of 0.96 is still possible.

CONCLUSION

TNF-a, IL-1b, 25(OH)D (Vit-D), IgG, and IgA were considered as predictors in children with MP-RA was investigated in this research.