Mutagenic effect of ultraviolet radiation and trimethyl psoralen in Mycoplasma towards minimal genome.

Mycoplasma, solely culturable bacteria with the smallest genome, is an important organism to understand the minimal form of life. Mutagenesis using mutagens is a useful methodology for understanding the essential regions of genomic information. Ultraviolet light and trimethyl psoralen are mutagens known to induce various mutations; the latter is reported to specifically induce deletions in nematodes. However, their mutagenic effects on mycoplasma are not known. Here, we exposed Metamycoplasma salivarium to ultraviolet (UV) light or trimethyl psoralen and UV as mutagens, and analyzed the mutational pattern after several rounds of serial cultivation ranging from 34 to 56 for different lineages. Our results showed that more deletions, but fewer point mutations, were induced with TMP and UV-A than with UV alone, indicating the usefulness of TMP in inducing deletions. In addition, we compared our results with mutational data from other studies, which suggested that both TMP-UVA and UV exposure induced point mutations that were highly biased toward C to T and G to A transitions. These data provide useful basic knowledge for mutational studies on M. salivarium.

The pharmacokinetics/pharmacodynamics integration of tilmicosin against Mycoplasma synoviae in vitro and in vivo.

Mycoplasma synoviae (MS) infection is a serious threat to poultry industry in China. Tilmicosin is a semisynthetic macrolide antibiotic used only in animals and has shown potential efficacy against MS, but there were no reported articles concerning the pharmacokinetics/pharmacodynamics (PK/PD) interactions of tilmicosin against MS in vitro and vivo. This study aimed to assess the antibacterial activity of tilmicosin against MS in vitro and in vivo using PK/PD model to provide maximal efficacy. The minimum inhibitory concentration (MIC) and killing rates of different drug concentrations were measured using the microdilution method in vitro. Then, tilmicosin was administered orally to the MS-infected chickens at doses of 7.5 and 60 mg/kg, and the PK parameters of tilmicosin in joint dialysates were determined using high-pressure liquid chromatography/tandem mass spectrometry (HPLC-MS/MS) combined with the microdialysis technique. The antibacterial effect (△E) was calculated when the infected chickens were administered a single oral dose of tilmicosin at 4, 7.5, 15, 30, and 60 mg/kg b.w. The PK and PD data were fitted using the Sigmoid Emax model to evaluate the PK/PD interactions of tilmicosin against MS. The bactericidal activity of tilmicosin against MS was concentration dependent. Furthermore, the PK/PD index of AUC0-72h/MIC exhibited the most optimal fitting results (R2 = .98). The MS load decreased by 1, 2, and 3 Log10 CFU/mL, then AUC/MIC was determined as 13.99, 20.53, and 28.23 h, respectively, and the bactericidal effect can be achieved when the dose of MS-infected chickens is at 31.64 mg/kg b.w. The findings of this study hold significant implications for optimizing the treatment regimen for MS infection.

Vaginitis and risk of sexually transmitted infections: results of a multi-center U.S. clinical study using STI nucleic acid amplification testing.

Significant increases in rates of sexually transmitted infections (STIs) caused by Trichomonas vaginalis (TV), Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and Mycoplasma genitalium (MG) are occurring in the United States. We present results of a U.S. study examining the intersection of STIs and vaginitis. Among 1,051 women with diagnoses for the presence or absence of bacterial vaginosis (BV) and/or symptomatic vulvovaginal candidiasis (VVC), 195 (18.5%) had one or more STIs, including 101 (9.6%) with TV, 24 (2.3%) with CT, 9 (0.8%) with NG, and 93 (8.8%) with MG. STI prevalence in BV-positive women was 26.3% (136/518), significantly higher than STI prevalence of 12.5% (59/474) in BV-negative women (P < 0.0002). Unlike infections with CT or NG, solo infections of MG or TV were each significantly associated with a diagnosis of BV-positive/VVC-negative (OR 3.0751; 95% CI 1.5797-5.9858, P = 0.0113, and OR 2.873; 95% CI 1.5687-5.2619, P = 0.0017, respectively) and with mixed infections containing MG and TV (OR 3.4886; 95% CI 1.8901-6.439, P = 0.0042, and OR 3.1858; 95% CI 1.809-5.6103, P = 0.0014, respectively). TV and MG infection rates were higher in all Nugent score (NS) categories than CT and NG infection rates; however, both STIs had similar comparative prevalence ratios to CT in NS 6-10 vs NS 0-5 (CT: 3.06% vs 1.4%, 2.2-fold; MG: 10.7% vs 6.1%, 1.8-fold; TV: 14.5% vs 7.0%, 2.1-fold). NG prevalence was relatively invariant by the NS category. These results highlight the complexity of associations of STIs with two major causes of vaginitis and underscore the importance of STI testing in women seeking care for abnormal vaginal discharge and inflammation. IMPORTANCE: This study reports high rates for sexually transmitted infections (STIs) in women seeking care for symptoms of vaginitis and bacterial vaginosis, revealing highly complex associations of STIs with two of the major causes of vaginal dysbiosis. These results underscore the importance of STI testing in women seeking care for abnormal vaginal discharge and inflammation.

Prevalence of sexually transmitted infections and associated risk factors among female sex workers in Guinea-Bissau.

OBJECTIVE: To estimate the prevalence of the curable sexually transmitted infections (STIs) Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, Trichomonas vaginalis and Treponema pallidum, to identify associated risk factors and to assess ciprofloxacin resistance in N. gonorrhoeae-positive specimens among female sex workers (FSWs) in Guinea-Bissau. METHODS: For this cross-sectional study, FSWs were recruited from October 2014 to May 2019. A questionnaire on STI risk factors was completed by the study participants, and the women were asked to provide a vaginal swab for nucleic acid amplification tests for C. trachomatis, N. gonorrhoeae, M. genitalium, T. vaginalis (Aptima, Hologica), as well as a blood sample for T. pallidum serological testing and discriminatory HIV-testing. The prevalence of STIs was determined, and multivariate logistic regression was used to identify STI risk factors. RESULTS: The study included 467 women. The prevalence of current infection with any curable STI was 46.7%, and the most common pathogen was T. vaginalis (26.3%), followed by M. genitalium (21.9%), C. trachomatis (11.8%), N. gonorrhoeae (10.1%) and T. pallidum (2.8%). The proportion of asymptomatic infections among the diagnosed STIs was 61.8%, 61.5%, 55.3%, 55.3% and 52.2% for C. trachomatis, T. pallidum, N. gonorrhoeae, T. vaginalis and M. genitalium, respectively. The prevalence of the gyrA S91F mutation conferring ciprofloxacin resistance in N. gonorrhoeae-positive specimens was 84.0%. Significant risk factors for having a curable STI were age and HIV-1 infection, while use of female condoms was a protective factor. CONCLUSION: This study demonstrated that the prevalence of curable STIs was high among FSWs in Guinea-Bissau during the study period, indicating an unmet need for STI services. Moreover, the results indicated that symptomatic treatment might be insufficient, highlighting a need for periodic aetiological testing to facilitate detection of asymptomatic as well as symptomatic STIs to stop ongoing transmission.

Revealing the mechanism: the influence of Baicalin on M1/M2 and Th1/Th2 imbalances in mycoplasma gallisepticum infection.

Mycoplasma gallisepticum (MG) is a pathogen that induces chronic respiratory illnesses in chickens, leading to tracheal and lung injury, and eliciting immune reactions that support sustained colonization. Baicalin, a compound found in scutellaria baicalensis, exhibits anti-inflammatory, antioxidant, and antibacterial properties. This study aimed to investigate the potential of baicalin in alleviating lung and cell damage caused by MG by restoring imbalances in M1/M2 and Th1/Th2 differentiation and to explore its underlying mechanism. In this research, a model for M1/M2 polarization induced by MG was initially developed. Specifically, infection with MG at a multiplicity of infection (MOI) of 400 for 6 h represented the M1 model, while infection for 10 h represented the M2 model. The polarization markers were subsequently validated using qRT-PCR, ELISA, and Western blot analysis. Baicalin disrupts the activation of M1 cells induced by MG and has the potential to restore the balance between M1 and M2 cells, thereby mitigating the inflammatory damage resulting from MG. Subsequent studies on MG-infected chickens detected imbalances in M1/M2 and Th1/Th2 differentiation in alveolar lavage fluid, as well as imbalances in macrophages and Th cells in the lung. The M1/Th1 model was exposed to MG for 5 d, while the M2/Th2 model was infected with MG for 7 d. The utilization of both light and electron transmission microscopes revealed that the administration of baicalin resulted in a reduction in the number of M1 cells, a decrease in cytoplasmic vacuoles, restoration of mitochondrial swelling and chromatin agglutination, as well as alleviation of alveolar rupture and inflammatory cell infiltration. Furthermore, baicalin restored MG-induced M1/M2 and Th1/Th2 imbalances and inhibited the phosphorylation of p38 and p65 proteins, thereby hindering the activation of the TLR4-p38 MAPK/NF-κB pathway. This study provides insights into the potential long-term effects of baicalin in MG infection and offers a theoretical basis for practical applications.

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.

Mycoplasma hyopneumoniae inhibits the unfolded protein response to prevent host macrophage apoptosis and M2 polarization.

Enzootic pneumonia caused by Mycoplasma hyopneumoniae (M. hyopneumoniae) has inflicted substantial economic losses on the global pig industry. The progression of M. hyopneumoniae induced-pneumonia is associated with lung immune cell infiltration and extensive proinflammatory cytokine secretion. Our previous study established that M. hyopneumoniae disrupts the host unfolded protein response (UPR), a process vital for the survival and immune function of macrophages. In this study, we demonstrated that M. hyopneumoniae targets the UPR- and caspase-12-mediated endoplasmic reticulum (ER)-associated classical intrinsic apoptotic pathway to interfere with host cell apoptosis signaling, thereby preserving the survival of host tracheal epithelial cells (PTECs) and alveolar macrophages (PAMs) during the early stages of infection. Even in the presence of apoptosis inducers, host cells infected with M. hyopneumoniae exhibited an anti-apoptotic potential. Further analyses revealed that M. hyopneumoniae suppresses the three UPR branches and their induced apoptosis. Interestingly, while UPR activation typically drives host macrophages toward an M2 polarization phenotype, M. hyopneumoniae specifically obstructs this process to maintain a proinflammatory phenotype in the host macrophages. Overall, our findings propose that M. hyopneumoniae inhibits the host UPR to sustain macrophage survival and a proinflammatory phenotype, which may be implicated in its pathogenesis in inducing host pneumonia.

Infection of Mycoplasma hominis in the left lower leg amputation wound of a patient with diabetes: a case report.

BACKGROUND: Mycoplasma hominis is typically found on the mucosal epithelium of the human genital tract, with infections being rare. However, when the mucosal barrier is compromised or in individuals with weakened immune systems, this microorganism can trigger infections in both intragenital and extragenital sites. This study offers a comprehensive overview of infections caused by the rare pathogen M. hominis. This overview helps laboratories identify M. hominis infections in a timely manner, thereby enabling earlier clinical intervention for patients. CASE PRESENTATION: A 75-year-old Taiwanese man with type 2 diabetes mellitus initially underwent a left lower extremity amputation following a severe infection caused by necrotizing fasciitis. Subsequently, a poorly healing wound developed at the site of amputation. Upon culturing the wound abscess, M. hominis was isolated and identified as the causative agent. CONCLUSIONS: Through this case, we present clinical and microbiological observations along with a review of the literature to deepen our understanding of M. hominis. Our findings can be used to develop laboratory diagnostic protocols and innovative therapeutic approaches.

Feline vector-borne haemopathogens in Türkiye: the first molecular detection of Mycoplasma wenyonii and ongoing Babesia ovis DNA presence in unspecific hosts.

BACKGROUND: Cats are hosts and reservoirs for many haemopathogens such as piroplasms, Rickettsia, hemotropic Mycoplasma, Bartonella, Ehrlichia, and Anaplasma, which are transmitted by various vector arthropods and some of which have a zoonotic concern. Although it is noteworthy that the rate of ownership of companion animals has increased in Türkiye in recent years and that cats account for a large proportion of these animals, there is limited research on the vector-borne infectious agents carried by them. The present study aimed to provide a comprehensive molecular epidemiological data and molecular characterization of feline vector-borne haemopathogens (FVBHs), including piroplasms, anaplasmataceae, rickettsias, haemoplasmas, and Bartonella species in Türkiye. In total, 250 feline blood samples were collected from client-owned cats (n = 203) and shelter cats (n = 47) brought to the Small Animal Hospital of Selcuk University, Veterinary Faculty. RESULTS: Overall, 40 (16%) cats were found to be infected with at least one of the investigated haemopathogens and piroplasm, Mycoplasma spp. and Bartonella spp. prevalence was 1.6%, 11.2%, and 4.8%, respectively. No Anaplasma/Ehrlichia spp. and Rickettsia spp. DNA was detected in the investigated feline samples. Sequence analysis revealed that all four piroplasms belonged to Babesia ovis with a 97.93-99.82% nucleotide sequence identity to 18S rRNA gene sequences from Spain and Türkiye, while some sequenced hemoplasmas were Mycoplasma haemofelis (Mhf), Candidatus Mycoplasma haemominutum (CMhm) and Mycoplasma wenyonii, and Bartonella spp. were Bartonella henselae and Bartonella koehlerae species. Co-infections with Mycoplasma spp. and Bartonella spp. were also detected in 4 cats (1.6%) in this study, where single infections were predominant. CONCLUSION: This study provides valuable information on zoonotically important feline vector-borne hemopathogens in Türkiye, some of which have received attention under the One Health perspective, and is the first molecular epidemiological study to demonstrate the presence of Babesia ovis, the causative agent of ovine babesiosis, and Mycoplasma wenyonii DNA, the causative agent of bovine haemotropic mycoplasmosis, in cats. Further studies on the roles of such pathogens detected in unspecific hosts and the host specificity of the vectors that transmit them will contribute to the elucidation of this situation.

The Epidemiology of Pathogens in Community-Acquired Pneumonia Among Children in Southwest China Before, During and After COVID-19 Non-pharmaceutical Interventions: A Cross-Sectional Study.

OBJECTIVE: This study aimed to investigate the pathogen epidemiology of community-acquired pneumonia (CAP) among children in Southwest China before, during and after the COVID-19 non-pharmaceutical interventions (NPIs). METHODS: Pathogen data of hospitalised children with CAP, including multiple direct immunofluorescence test for seven viruses, bacterial culture and polymerase chain reaction (PCR) for Mycoplasma pneumoniae, were analysed across three phases: Phase I (pre-NPIs: 1 January 2019 to 31 December 2019), Phase II (NPI period: 1 January 2020 to 31 December 2020) and Phase III (post-NPIs: 1 January 2023 to 31 December 2023). RESULTS: A total of 7533 cases were enrolled, including 2444, 1642 and 3447 individuals in Phases I, II and III, respectively. M. pneumoniae predominated in Phases I and III (23.4% and 35.5%, respectively). In Phase II, respiratory syncytial virus (RSV) emerged as the primary pathogen (20.3%), whereas detection rates of influenza A virus (Flu A) and M. pneumoniae were at a low level (1.8% and 9.6%, respectively). In Phase III, both Flu A (15.8%) and M. pneumoniae epidemic rebounded, whereas RSV detection rate returned to Phase I level, and detection rates of Streptococcus pneumoniae and Haemophilus influenzae decreased significantly compared to those in Phase I. Detection rates of adenovirus and parainfluenza virus type 3 decreased phase by phase. Age-stratified analysis and monthly variations supported the above findings. Seasonal patterns of multiple pathogens were disrupted during Phases II and III. CONCLUSIONS: COVID-19 NPIs exhibited a distinct impact on CAP pathogen epidemic among children, with post-NPIs increases observed in M. pneumoniae and Flu A prevalence. Continuous pathogen monitoring is crucial for effective prevention and control of paediatric CAP.

Distinct clinical characteristics of bocavirus and Mycoplasma pneumoniae infection in children plastic bronchitis.

BACKGROUND: This study investigated clinical and laboratory characteristics of human bocavirus type 1 (HBoV1)-plastic bronchiolitis (PB), Mycoplasma pneumoniae (MP)-associated plastic bronchitis (PB) and MP-NPB in children, highlighting inflammation, coagulation, and bronchoscopic needs. METHODS: Data on preschool children with PB during HBoV1 or MP infection were collected, comparing MP-PB to severe Mycoplasma pneumoniae pneumonia. RESULT: Compared with the MP-PB group, the HBoV1-PB group, with younger children, had significantly milder clinical symptoms but higher WBC counts (p = .028). The MP-PB group exhibited notably elevated Fibrinogen (p = .045) and d-dimer levels (p < .001). When contrasting the MP-PB with the MP-NPB group, children in MP-PB group still had higher levels of d-dimer and increased inflammatory indicators such as C-reactive protein, procalcitonin, lactate dehydrogenase, and interleukin-6, which were significantly elevated compared with the MP-NPB group. MP-PB showed a higher prevalence of plastic bronchial casts in lower lobes (p = .016) and a dominance of neutrophils in BALF cytology. Additionally, children in the MP-PB group tended to undergo a greater number of bronchoscopies. CONCLUSION: This study identifies key differences in plastic bronchitis in children due to HBoV1 and MP, highlighting HBoV1's milder inflammation in younger kids and MP's link to severe inflammatory and coagulation responses, guiding clinical diagnosis and treatment.

Mycoplasma pneumoniae-induced Kawasaki disease via PINK1/Parkin-mediated mitophagy.

Kawasaki disease (KD) is a systemic vasculitis with an unknown cause that primarily affects children. The objective of this study was to explore the function and underlying mechanism of mitophagy in Mycoplasma pneumoniae (MP)-induced KD. To create MP-induced KD models, Human coronary endothelial cells (HCAECs) and DBA/2 mice were employed and treated with Mp-Lipid-associated membrane proteins （LAMPs）. Lactate dehydrogenase (LDH) levels were tested to determine cellular damage or death. The inflammatory cytokines tumor necrosis factor (TNF)--α and interleukin (IL)-6 were measured using the Enzyme-Linked Immunosorbent Assay (ELISA) method. RT-qPCR and Western blotting were used to determine the expression of Intercellular Adhesion Molecule(ICAM)-1, vascular cell adhesion molecule (VCAM)-1, inducible nitric oxide synthase(iNOS), LC3, p62, PINK1(a mitochondrial serine/threonine-protein kinase), and PARKIN(a cytosolic E3-ubiquitin ligase). The adenosine triphosphate （ATP）, reactive oxygen species （ROS）, and mitochondrial membrane potential（MMP） levels were measured to determine mitochondrial function. Mitophagy was investigated using immunofluorescence and a mitophagy detection test. Autophagosome and mitochondrial morphology were examined using transmission electron microscopy. To identify inflammatory cell infiltration, hematoxylin and eosin staining was utilized. Mp-LAMPs increased the levels of TNF-α, IL-6, ICAM-1, VCAM-1, and iNOS in an HCAEC cell model, along with LDH release. After Mp-LAMPs exposure, there was a rise in LC3 and a reduction in p62. Meanwhile, the expression of PINK1 and Parkin was increased. Cyclosporin A dramatically increased ATP synthesis and MMP in HCAEC cells treated with Mp-LAMPs, while suppressing ROS generation, demonstrating excessive mitophagy-related mitochondrial dysfunction. Additionally, neither body weight nor artery tissue were affected due to PINK1 and Parkin suppression Cyclosporin A in Mp-LAMPs-treated mice. These findings indicated that PINK1/Parkin-mediated mitophagy inhibition may be a therapeutic target for MP-induced KD.

High-throughput rapid amplicon sequencing for multilocus sequence typing of Mycoplasma ovipneumoniae from archived clinical DNA samples.

Introduction: Spillover events of Mycoplasma ovipneumoniae have devastating effects on the wild sheep populations. Multilocus sequence typing (MLST) is used to monitor spillover events and the spread of M. ovipneumoniae between the sheep populations. Most studies involving the typing of M. ovipneumoniae have used Sanger sequencing. However, this technology is time-consuming, expensive, and is not well suited to efficient batch sample processing. Methods: Our study aimed to develop and validate an MLST workflow for typing of M. ovipneumoniae using Nanopore Rapid Barcoding sequencing and multiplex polymerase chain reaction (PCR). We compare the workflow with Nanopore Native Barcoding library preparation and Illumina MiSeq amplicon protocols to determine the most accurate and cost-effective method for sequencing multiplex amplicons. A multiplex PCR was optimized for four housekeeping genes of M. ovipneumoniae using archived DNA samples (N = 68) from nasal swabs. Results: Sequences recovered from Nanopore Rapid Barcoding correctly identified all MLST types with the shortest total workflow time and lowest cost per sample when compared with Nanopore Native Barcoding and Illumina MiSeq methods. Discussion: Our proposed workflow is a convenient and effective method for strain typing of M. ovipneumoniae and can be applied to other bacterial MLST schemes. The workflow is suitable for diagnostic settings, where reduced hands-on time, cost, and multiplexing capabilities are important.

Construction of a predictive model of respiratory endoscopic intervention in children with lobar pneumonia caused by Mycoplasma pneumoniae infection.

Background: This study aimed to analyze the clinical features of children with lobar pneumonia caused by Mycoplasma pneumoniae (MP) infection, to explore the independent risk factors for bronchoscopic intervention in children with lobar pneumonia caused by MP infection. There is a lack of objective assessment tools to guide the use of bronchoscopy in clinical practice. For children with lobar pneumonia caused by MP infection, whether line shall be actively bronchoscope intervention therapy remains to be further defined. We also aimed to construct an early warning model of bronchoscopic intervention to provide an objective evaluation tool for clinicians. Methods: We collected the clinical data of 533 children with lobar pneumonia caused by MP infection. The patients were divided into three groups according to the interventional indications for bronchoscopy and whether they were treated with bronchoscopic intervention, and the clinical features and prognosis of the three groups were compared. A binary logistic regression analysis was performed on the indicators with a significance value of P<0.05, which we retrieved from the comparative analysis between the first two groups to uncover the independent risk factors and regression equations concerning bronchoscopic intervention. The regression coefficient (ß) of our regression model was then used to score related values in the model to construct a predictive scoring model of bronchoscopic intervention for the treatment of children with lobar pneumonia caused by MP infection. Results: Children with lobar pneumonia caused by MP infection who demonstrated absolute indications for bronchoscopy exhibited more severe clinical manifestations, and children without absolute indications for bronchoscopy had a better prognosis even without bronchoscopic intervention. To establish our early warning model of bronchoscopic intervention for children with lobar pneumonia caused by MP infection, we used the following indices: C-reactive protein ≥20.94 mg/L (ß1=2.253) received 3 points, while a fever duration before bronchoscopy ≥6.5 d (ß2=1.424), lactate dehydrogenase ≥461.5 U/L (ß3=1.246), or fever (ß4=1.223) each received 2 points, and the complication of pleural effusion (ß5=0.841) received 1 point, for a total possible score of 10 points. Conclusions: When the score for the children with lobar pneumonia caused by MP infection was ≥6, the possibility of bronchoscopic intervention for treatment was >80%. The higher the score, the greater the possibility of bronchoscopic intervention.

Construction of a nomogram for early diagnosis of refractory Mycoplasma pneumoniae pneumonia in children.

Background: Refractory Mycoplasma pneumoniae pneumonia (RMPP) has a serious, rapid progression that can easily cause a variety of extra-pulmonary complications. Therefore, the early identification of RMPP is crucial. This study aimed to construct and validate a risk prediction model based on clinical manifestations, laboratory blood indicators, and radiological findings to help clinicians identify patients who are at high risk of RMPP. Methods: We retrospectively analyzed the medical records of 369 children with Mycoplasma pneumoniae pneumonia (MPP) admitted to Xi'an Children's Hospital, China. The demographics, clinical features, laboratory data, and radiological findings between the RMPP group and the general Mycoplasma pneumoniae pneumonia (GMPP) group were compared and subjected to univariate and multivariate logistic regression analyses. Results: The fever peak and duration of the children in the RMPP group (n=86) were higher and longer compared with those in the GMPP group (n=283) (P<0.05). There was a significant difference in the incidence of lobar pneumonia and pleural effusion in pulmonary imaging between the two groups (P<0.05). Laboratory tests showed that the children with RMPP had lower serum uric acid (SUA) and albumin (ALB) as compared with the GMPP group (P<0.05). White blood cells (WBCs), neutrophil count (NEP), erythrocyte sedimentation rate (ESR), procalcitonin (PCT), C-reactive protein (CRP), and neutrophil-to-lymphocyte ratio (NLR) were higher in the RMPP group (P<0.05). Binary logistic regression analysis showed that the fever duration, pleural effusion, WBC, NEP, lactate dehydrogenase (LDH), CRP, NLR, and SUA levels were independent predictors of RMPP (P<0.05). The receiver operator characteristic (ROC) curve results showed fever duration, WBC, NEP, CRP, LDH, SUA, and NLR had good predictive value. The areas under the curve (AUCs) were 0.861, 0.730, 0.758, 0.837, 0.868, 0.744, and 0.713 and the best cutoff values were 10.50, 10.13, 6.43, 29.45, 370.50, 170.50, and 3.47, respectively. Finally, fever duration of more than 10.5 days, pleural effusion, WBC >10.13×109/L, NEP >6.43×109/L, CRP >29.45 mg/L, LDH >370.50 U/L, NLR >3.47, and SUA <170.5 µmol/mL constructed a prediction model of RMPP. According to internal validation, the mean AUC of the nomogram based on the development dataset was 0.956 [95% confidence interval (CI): 0.937-0.974] with good discrimination ability for predicting RMPP patients. The calibration plot and Hosmer-Lemeshow test (P=0.70) of the prediction model showed good consistency between the predicted probability and actual probability. Decision curve analysis (DCA) showed that the nomogram is clinically useful. Conclusions: The simple and easy-to-use nomogram can help clinicians, especially primary doctors, to make early diagnoses of RMPP.

Integrated structural proteomics and machine learning-guided mapping of a highly protective precision vaccine against mycoplasma pulmonis.

Mycoplasma pulmonis (M. pulmonis) is an emerging respiratory infection commonly linked to prostate cancer, and it is classified under the group of mycoplasmas. Improved management of mycoplasma infections is essential due to the frequent ineffectiveness of current antibiotic treatments in completely eliminating these pathogens from the host. The objective of this study is to design and construct effective and protective vaccines guided by structural proteomics and machine learning algorithms to provide protection against the M. pulmonis infection. Through a thorough examination of the entire proteome of M. pulmonis, four specific targets Membrane protein P80, Lipoprotein, Uncharacterized protein and GGDEF domain-containing protein have been identified as appropriate for designing a vaccine. The proteins underwent mapping of cytotoxic T lymphocyte (CTL), helper T lymphocyte (HTL) (IFN)-γ ±, and B-cell epitopes using artificial and recurrent neural networks. The design involved the creation of mRNA and peptide-based vaccine, which consisted of 8 CTL epitopes associated by GGS linkers, 7 HTL (IFN-positive) epitopes, and 8 B-cell epitopes joined by GPGPG linkers. The vaccine designed exhibit antigenic behavior, non-allergenic qualities, and exceptional physicochemical attributes. Structural modeling revealed that correct folding is crucial for optimal functioning. The coupling of the MEVC and Toll-like Receptors (TLR)1, TLR2, and TLR6 was examined through molecular docking experiments. This was followed by molecular simulation investigations, which included binding free energy estimations. The results indicated that the dynamics of the interaction were stable, and the binding was strong. In silico cloning and optimization analysis revealed an optimized sequence with a GC content of 49.776 % and a CAI of 0.982. The immunological simulation results showed strong immune responses, with elevated levels of active and plasma B-cells, regulatory T-cells, HTL, and CTL in both IgM+IgG and secondary immune responses. The antigen was completely cleared by the 50th day. This study lays the foundation for creating a potent and secure vaccine candidate to combat the newly identified M. pulmonis infection in people.

Exploring the pathogenicity of Mycoplasma pneumoniae: Focus on community-acquired respiratory distress syndrome toxins.

Community-Acquired Respiratory Distress Syndrome Toxin (CARDS TX) is a unique exotoxin produced by Mycoplasma pneumoniae (MP) and has been confirmed to possess ADP-ribosyltransferase (ART) and vacuolating activities. CARDS TX binds to receptors on the surfaces of mammalian cells followed by entry into the cells through clathrin-mediated endocytosis, and exerts cytotoxic effects by undergoing retrograde transport and finally cleavage on endosomes and cellular organelles. In addition, CARDS TX can trigger severe inflammatory reactions resulting in airway dysfunction, producing allergic inflammation and asthma-like conditions. As a newly discovered virulence factor of MP, CARDS TX has been extensively studied in recent years. As resistance to macrolide drugs has increased significantly in recent years and there is no vaccine against MP, the development of a vaccine targeting CARDS TX is considered a potential preventive measure. This review focuses on recent studies and insights into this toxin, providing directions for a better understanding of MP pathogenesis and treatment. IMPORTANCE: A serious hazard to worldwide public health in recent years, Mycoplasma pneumoniae (MP) is a prominent bacterium that causes community-acquired pneumonia (CAP) in hospitalized children. Due to their high prevalence and fatality rates, MP infections often cause both respiratory illnesses and extensive extrapulmonary symptoms. It has recently been shown that MP produces a distinct exotoxin known as Community-Acquired Respiratory Distress Syndrome Toxin (CARDS TX). Mycoplasma pneumoniae pneumonia (MPP)-like tissue injury is caused by this toxin because it has both ADP-ribosyltransferase and vacuolating properties. A better knowledge of MP etiology and therapy is provided by this review, which focuses on latest research and insights into this toxin.

Serum inflammatory markers in children with Mycoplasma pneumoniae pneumonia and their predictive value for mycoplasma severity.

BACKGROUND: Mycoplasma pneumoniae pneumonia (MPP) significantly impacts pediatric health, necessitating markers for early severe disease identification. AIM: To investigate the correlation between serum inflammatory marker and the severity of MPP in children. METHODS: A prospective study was carried out from January 2023 to November 2023. A total of 160 children with MPP who underwent treatment were selected: 80 had severe MPP and 80 had mild MPP. Clinical and laboratory data were collected at the time of hospital admission and during hospitalization. Receiver operating characteristic curves were utilized to assess the diagnostic and prognostic for severe MPP. RESULTS: Fever duration and length of hospitalization in pediatric patients with severe MPP exceeded those with mild MPP. The incidence of pleural effusion, lung consolidation, and bronchopneumonia on imaging was markedly elevated in the severe MPP cohort compared to the mild MPP cohort. In contrast to the mild cohort, there was a notable increase in C-reactive protein (CRP), procalcitonin (PCT), erythrocyte sedimentation rate, lactic dehydrogenase, D-dimer, and inflammatory cytokines [interleukin (IL)-6, IL-8, IL-10 and tumor necrosis factor (TNF)-α] in the severe MPP group were significantly higher. CONCLUSION: Serum inflammatory markers (CRP, PCT, IL-6, D-dimer, IL-10 and TNF-α) were considered as predictors in children with severe MPP.

Clinical differences between Mycoplasma pneumoniae pneumonia and Streptococcus pneumoniae pneumonia: a case control study.

Introduction: Mycoplasma pneumoniae pneumonia (MPP) and Streptococcus pneumoniae pneumonia (SPP) are frequent causes of respiratory tract infection, the aims of the study were to explore the differences in clinical features between children with MPP and those with SPP. Methods: This retrospective study included admitted children who were diagnosed with MPP or SPP over 5 years from January 2015 to January 2020. Children with MPP were compared to children with SPP in terms of clinical features. Results: 506 patients with MPP were compared to 311 patients with SPP in terms of clinical differences. The MPP group with a median age of 60 [29-89] months and the SPP group with a median age of 24 [10-40] months. Patients with MPP were older and had a higher occurrence of receiving antibiotics before admission, fever, dry cough, polypnea and diarrhea than patients with SPP (all p < 0.01). Patients with SPP were more likely to have wheezing, cyanosis and irritability (all p < 0.01). Laboratory findings in our study showed that there were significant differences between MPP and SPP patients in mean leucocyte count, neutrophil % (N%), lymphocyte % (L%), ALT levels, AST levels, LDH levels and incidence of accelerated procalcitonin (PCT) (all p < 0.01). Lower age, no dry cough, no polypnea, lower LDH levels, and higher PCT might lead to the diagnosis of SPP. Our study showed that age had a higher accuracy in predicting MPP than LDH levels, with an age >48.5 months shown to be an independent predictive factor for the early evaluation and identification of MPP. Discussion: In conclusion, patients with MPP and SPP usually present with fever, cough and some nonspecific symptoms. Our study showed that age, dry cough, polypnea, LDH levels, and PCT levels were independent predictive factors associated with MPP and SPP.

Expert consensus on the diagnosis and treatment of macrolide-resistant Mycoplasma pneumoniae pneumonia in children.

BACKGROUND: Mycoplasma pneumoniae (M. pneumoniae) is a significant contributor to community-acquired pneumonia among children. Since 1968, when a strain of M. pneumoniae resistant to macrolide antibiotics was initially reported in Japan, macrolide-resistant M. pneumoniae (MRMP) has been documented in many countries worldwide, with varying incidence rates. MRMP infections lead to a poor response to macrolide antibiotics, frequently resulting in prolonged fever, extended antibiotic treatment, increased hospitalization, intensive care unit admissions, and a significantly higher proportion of patients receiving glucocorticoids or second-line antibiotics. Since 2000, the global incidence of MRMP has gradually increased, especially in East Asia, which has posed a serious challenge to the treatment of M. pneumoniae infections in children and attracted widespread attention from pediatricians. However, there is still no global consensus on the diagnosis and treatment of MRMP in children. METHODS: We organized 29 Chinese experts majoring in pediatric pulmonology and epidemiology to write the world's first consensus on the diagnosis and treatment of pediatric MRMP pneumonia, based on evidence collection. The evidence searches and reviews were conducted using electronic databases, including PubMed, Embase, Web of Science, CNKI, Medline, and the Cochrane Library. We used variations in terms for "macrolide-resistant", "Mycoplasma pneumoniae", "MP", "M. pneumoniae", "pneumonia", "MRMP", "lower respiratory tract infection", "Mycoplasma pneumoniae infection", "children", and "pediatric". RESULTS: Epidemiology, pathogenesis, clinical manifestations, early identification, laboratory examination, principles of antibiotic use, application of glucocorticoids and intravenous immunoglobulin, and precautions for bronchoscopy are highlighted. Early and rapid identification of gene mutations associated with MRMP is now available by polymerase chain reaction and fluorescent probe techniques in respiratory specimens. Although the resistance rate to macrolide remains high, it is fortunate that M. pneumoniae still maintains good in vitro sensitivity to second-line antibiotics such as tetracyclines and quinolones, making them an effective treatment option for patients with initial treatment failure caused by macrolide antibiotics. CONCLUSIONS: This consensus, based on international and national scientific evidence, provides scientific guidance for the diagnosis and treatment of MRMP in children. Further studies on tetracycline and quinolone drugs in children are urgently needed to evaluate their effects on the growth and development. Additionally, developing an antibiotic rotation treatment strategy is necessary to reduce the prevalence of MRMP strains.