Clinical characteristics of community-acquired pneumonia in children caused by mycoplasma pneumoniae with or without myocardial damage:A single-center retrospective study

BACKGROUND Mycoplasma pneumoniae(MP)is a prevalent pathogen that causes respiratory infections in children and adolescents.AIM To assess the differences in the clinical features of MP-associated communityacquired pneumonia(CAP)in children who presented with mild or severe mycoplasma pneumoniae pneumonia(MPP);to identify the incidence of myocardial damage between the two groups.METHODS This work is a retrospective study.We identified children between 2 mo and 16 years of age with clinical and radiological findings consistent with CAP.We admitted patients to the inpatient department of the Second Hospital of Jilin University,Changchun,China,from January 2019 to December 2019.RESULTS A total of 409 hospitalized patients were diagnosed with MPP.Among them were 214(52.3%)males and 195(47.7%)females.The duration of fever and cough was the longest in severe MPP cases.Similarly,plasma levels of highly sensitive Creactive protein(t=-2.834,P<0.05),alanine transaminase(t=-2.511,P<0.05),aspartate aminotransferase(t=-2.939,P<0.05),and lactate dehydrogenase(LDH)(t=-2.939,P<0.05)were all elevated in severe MPP cases compared with mild MPP cases,and these elevations were statistically significant(P<0.05).Conversely,the neutrophil percentage was significantly lower in severe MPP cases than in mild MPP cases.The incidence of myocardial damage was significantly higher in severe MPP cases than in mild MPP cases(χ^(2)=157.078,P<0.05).CONCLUSION Mycoplasma pneumoniae is the main cause of CAP.The incidence of myocardial damage was higher and statistically significant in severe MPP cases than in mild MPP cases.

Chinese herbal medicine combined with Western medicine for Mycoplasma pneumoniae pneumonia in children:An overview of systematic reviews

Objective:To summarize the characteristics and evaluate the quality of the methodology and evidence within systematic reviews(SRs)of Chinese herbal medicine(CHM)for Mycoplasma pneumoniae pneumonia(MPP)inchildren.Methods:SRs of randomized controlled trials were searched using PubMed,the Cochrane Library,Embase,the Chinese National Knowledge Infrastructure Databases(CNKI),the Chinese Scientific Journals Database(VIP),Wanfang,and the SinoMed Database.SRs on the use of CHM alone or in combination with Western medications for MPP in children were included.The study compared the effects of Western medicine alone with those of CHM.The evidence quality using the A Measurement Tool to Assess Systematic Reviews(AMSTAR)2,the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)2020,and the Grading of Recommendations,Assessment,Development,and Evaluation(GRADE)criteria.The primary indicators were the total effective rate,fever subsidence time,and cough disappearance time.The secondary outcomes were pulmonary rale disappearance time,average hospitalization time,lung X-ray infiltrate disappearance time,immunological indices,and inflammatory cytokine levels.Results:Twelve relevant SRs were included;75%(9/12)were assessed as very low quality,and 25%(3/12)Were rated as low quality using the AMSTAR 2 criteria.According to the PRISMA 2020 checklist,the average SR score was 20.3 out of a 27 point maximum.In all SRs,CHM demonstrated improvement in symptoms and signs among children with MPP.The evidence quality using the GRADE criteria ranged from"very low"(>50%)to"moderate"(<5%).The most common downgrading factor was imprecision,followed by publication bias and inconsistency.Conclusion:This overview highlights the limited quality of the methodology and evidence of the included SRs.Although the included studies showed the beneficial effects of CHM on MPP in children,it was difficult to draw firm conclusions owing to methodological flaws.

Standardization of a Real-time PCR System for Quantitative Detection of Mycoplasma hyopneumoniae

This study was conducted to develop a method for accurate quantification of Mycoplasma hyopneumoniae during vaccine production or experimental research. Primer and probe concentration that gave the highest ΔRn and the lowest Ct were selected to establish the real-time PCR system for the detection of M. hyopneumoniae. Template DNA of M. hyopneumoniae was extracted by boiling under different conditions and detected by real-time PCR to determine the optimal conditions for DNA extraction. Thereafter, intra-and inter-batch reproducibility tests were carried out using a standard plasmid to evaluate the stability of the PCR system. Subsequently, the effect of medium composition on the quantitative detection was evaluated. Finally, the correlation between real-time PCR and CCU method was explored. The optimal primer and probe concentration for real-time PCR were 0.4 and 0.2 μmol/L, respectively. The intra-and inter-batch coefficients of variation(CV) in Ct value of 10~4-10~9 copies/μl standard plasmid were <5%, indicating good reproducibility of the real-time PCR system. Following incubation in a boiling water bath for 10 min, M. hyopneumoniae samples can be used directly as a template in subsequent real-time PCR assays,and good intra-batch and inter-batch reproducibility was observed. The working concentration of KM2 medium should be less than the 1/10 of the concentration of the stock solution to minimize its influence on the quantitative detection. Spearman's correlation analysis revealed that the log of CCU and the log of DNA copy number had a significant positive relationship(r=0.797,P=0.000). Thus, the two methods can be used in combination in the quantitative detection of M. hyopneumoniae. In summary, a rapid, stable and accurate quantitative PCR system for detecting M. hyopneumoniae culture was established in this study, which provides a technical means for accurate quantification of M. hyopneumoniae in vaccine production and laboratory tests.

Establishment of a Predictive Diagnostic Model for Acute Mycoplasma Pneumoniae Infection in Elderly Patients with Community-acquired Pneumonia

We established a diagnostic model to predict acute Mycoplasma pneumoniae （M. pneumonia） infection in elderly Community-acquired pneumonia （CAP） patients. We divided 456 patients into acute and non-acute M. pneumoniae infection groups. Binary logistic regression and receiver operating characteristic （ROC） curves were used to establish a predictive model. The following independent factors were identified： age 〉 70 years; serum cTNT level 〉 0.0S ng/mL; lobar consolidation; mediastinal lymphadenopathy; and antibody titer in the acute phase 〉 1：40. The area under the ROC curve of the model was 0.923 and a score of 2 7 score predicted acute M. pneumoniae infection in elderly patients with CAP. The predictive model developed in this study has high diagnostic accuracy for the identification of elderly acute M. pneumoniae infection.

Lymph-node-first presentation of Kawasaki disease in a 12-year-old girl with cervical lymphadenitis caused by Mycoplasma pneumoniae:A case report

BACKGROUND To the best of our knowledge,cases of Kawasaki disease(KD)occurring at the age of 12 are rare,even in Asia where the incidence of KD is high.We report a case of lymph-node-first presentation of KD(NFKD)in a 12-year-old girl with Mycoplasma pneumoniae(M.pneumoniae)infection who presented with prolonged fever and lymphadenitis refractory to macrolide antibiotics.CASE SUMMARY A previously healthy 12-year-old girl presented with fever,myalgia,sore throat,swelling,and tenderness on the right side of the neck.She was initially diagnosed with lymphadenitis caused by M.pneumoniae refractory to macrolide antibiotics.She had elevated brain natriuretic peptide(BNP)levels.Finally,the patient was diagnosed with KD.After receiving intravenous immunoglobulin,the fever resolved,and her symptoms improved.CONCLUSION NFKD should be differentiated from adolescent lymphadenitis presenting with prolonged fever by checking the BNP level early.

Kawasaki disease, <i>Mycoplasma pneumoniae</i>infection and anaplastic large cell lymphoma: An uncommon association

Kawasaki disease (KD) is an acute febrile systemic vasculitis occurring predominantly in young children less than 5 years of age. Although imperfectly known, the aetiopathogenesis of KD would be secondary to immunological abnormalities that could constitute a favourable terrain for neoplasms. We report on a case in a 2-year-old girl who presented clinical manifestations compatible with Kawasaki disease complicated by coronary aneurysm. Aetiopathological investigations revealed M. pneumoniae infection as specific IgM were present in the serum (Elisa). The patient was initially treated by intravenous immunoglobulins (IVIG) and aspirin to anti-inflammatory dose. Following a few days of desquamation, resolution of the symptomatology occurred. Four weeks later she developed disseminated tumorous syndrome. Lymph node biopsy revealed massive infiltration by large cells lymphomatous proliferation. Histologic and immunophenotypic findings were characteristic of ALK-1+ anaplastic large cell lymphoma. Four weeks later, the patient died from a severe nosocomial infection complicated by septic shock. Our observation is the first cases describing the association between anaplastic large cell lymphoma, KD and M. pneumoniae. Immunologic disorder due to KD and M. pneumoniae infection may play probably a central role for malignancy.

The Effect of Azithromycin in Treating Mycoplasma Pneumonia in Children

Objective:To discuss and analyze the effect of azithromycin in the treatment of mycoplasma pneumonia in children.Methods:A total of 120 children with mycoplasma pneumonia who were admitted to the Department of Pediatrics of our hospital from January 2022 to December 2022 were selected as the research subjects.They were divided into an azithromycin group and a reference group according to the random number drawing method,with 60 cases in each group.The azithromycin group was treated with azithromycin,and the reference group was treated with conventional treatment.The efficacy of treatment,laboratory indicators,platelet count and D-dimer,and adverse reactions of both groups were compared.Results:The efficacy of the azithromycin group was significantly higher than that of the reference group(P<0.05).Before treatment,there were no significant differences in the laboratory indicators like ferritin,procalcitonin(PCT),and erythrocyte sedimentation rate(ESR)between the two groups(P>0.05);after treatment,the laboratory indicators of the azithromycin group were significantly better than those of the reference group(P<0.05).Before treatment,there was no statistically significant difference in platelet count and D-dimer between the groups(P>0.05);after medication,the platelet count,and D-dimer in the azithromycin group were significantly better than those in the reference group(P<0.05).The total incidence of adverse reactions in the azithromycin group was significantly lower than that in the reference group(P<0.05).Conclusion:Azithromycin is more effective in treating mycoplasma pneumonia in children,and has certain clinical value.

Chronic Pulmonary Infection Caused by Mycoplasma Pneumoniae Leading to Pulmonary Arteriole Remodeling and Pulmonary Hypertens

The pulmonary arteriole remodeling in Wistar rats with respiratory infection induced by mycoplasma pneumoniae was observed using light microscopy and morphometry. The pulmonary artery pressure(PAP) and index of right ventricular hypertrophy (RVHI) were measured. The intimal and medial hypertrophy can be seen in the pulmonary arterioles, leading to vessei wall thickening and narrowing of the lumina. The total number of the pulmonary arterioles decreased (P <0.01) , and both pulmonary hypertension (Ppa 4.11±0. 19 kPa) and right ventricular hypertrophy (RVHI=34.96±3. 91%) occurred. In addition, an interstitial pulmonary fibrosis (IPF) was found, in which the content of collagen in the lung tissue changed, i. e. , type Ⅰcollagen increased whereas type Ⅲ one decreased, and the ratio of type Ⅰ collagen to type Ⅲ one increased. It suggested that respiratory infection induced by repeated MP may result in remodeling of pulmonary arterioles and are closely related to pulmonary hypertension.

Can the detection of IgA anti-Mycoplasma pneumoniae added to IgM increase diagnostic accuracy in patients with infections of the lower respiratory airways?

AIM To evaluate the increase in diagnostic yield, by using IgA in addition to IgM, instead of IgM alone, in relation to the age of the patients.METHODS The study considered 1067 blood samples from patients with clinical signs of lower respiratory tract infections, tested for anti-Mycoplasma IgG, IgM and IgA antibody.RESULTS The increase in diagnostic yield with IgA, compared to IgM detection alone was of 3.5% with statistically significant differences between age groups(0.8% for those equal/under 50 years of age and 4.3% for those over 50).CONCLUSION Our findings demonstrate that IgA detection lead to a twofold increase in the number of diagnoses among the older age groups, but it did not result in relevant increase among the younger age groups.

Therapeutic effect of montelukast sodium + methylprednisolone +azithromycin therapy for patients with mycoplasma pneumonia

Objective: To explore the therapeutic effect of montelukast sodium + methylprednisolone+ azithromycin therapy for patients with mycoplasma pneumonia. Methods: A total of 88 patients with mycoplasma pneumonia who were treated in our hospital between July 2015 and June 2017 were collected and divided into group A (oral azithromycin), group B (oral azithromycin + methylprednisolone), group C (oral azithromycin + montelukast sodium) and group D (oral montelukast sodium + methylprednisolone + azithromycin), and they were continuously treated for 1 week. The differences in therapeutic effect, systemic inflammatory response and stress response were compared among the four groups of patients. Results:After 1 week of treatment, the overall response rate of group D was higher than that of group A, group B and group C, and the overall response rate of group B and group C were higher than that of group A respectively;serum inflammatory factors C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor α (TNF-α), cortisol (COR), malondialdehyde (MDA) and advanced oxidation protein product (AOPP) levels of group D were lower than those of group A, group B and group C, and serum CRP, IL-6, TNF-α, COR, MDA and AOPP levels of group B and group C were lower than those of group A respectively. Conclusion:Montelukast sodium + methylprednisolone + azithromycin therapy can significantly improve the therapeutic effect and inhibit the systemic inflammatory and stress response in patients with mycoplasma pneumonia.

The value of IgM and IgG contents for the diagnosis and judgment of mycoplasma pneumonia in children

Objective: To explore the value of IgM and IgG contents for the diagnosis and judgment of mycoplasma pneumonia in children. Methods: 560 children with mycoplasma pneumonia who received inpatient treatment in our hospital between October 2016 and October 2017 were selected as mycoplasma pneumonia group, and 200 healthy children who received vaccination in our hospital during the same period were selected as normal control group. The differences in peripheral blood IgM and IgG contents as well as serum inflammatory factor and pulmonary surfactant protein contents were compared between the two groups, and Pearson test was used to evaluate the inner link of peripheral blood IgM and IgG contents with inflammatory factors and pulmonary surfactant proteins in children with mycoplasma pneumonia. Results: Peripheral blood IgM and IgG contents of mycoplasma pneumonia group were higher than those of normal control group;serum inflammatory factors MCP-4, IL-5, IL-13, IL-17, IL-18 and IL-23 contents were higher than those of normal control group;serum pulmonary surfactant proteins SP-A, SP-B, SP-C and SP-D contents were higher than those of normal control group. Correlation analysis showed that peripheral blood IgM and IgG contents in children with mycoplasma pneumonia were positively correlated with the contents of inflammatory factors and pulmonary surfactant proteins. Conclusion: Peripheral blood IgM and IgG contents are abnormally high in children with mycoplasma pneumonia, and they are closely related to the inflammatory response and lung injury degree.

Dynamic changes of immune function and inflammatory factors in infants with mycoplasma pneumoniae infection in different stages

Objective:To investigate the levels of immune function and inflammatory factors in children with mycoplasma pneumonia (MP) infection in different stages and its clinical significance. Methods: A total of 100 children with MPP hospitalized from September 2014 to May 2015 were selected as the observation group and divided into two groups of MPP acute period and recovery period on the basis of the infection degree, and 50 healthy children were selected as control group at the same time, detect the immunoglobulin (IgG, IgA, IgM) and complement (C3, C4), peripheral T lymphocyte subsets (CD3+, CD4+, CD8+) and inflammatory factors (IL-2, IL-6, TNF-α, IL-8, IL-10, IL-13) of three groups of infants.Results:immunoglobulin IgG levels of recovery period were significantly higher than that in acute stage and the control group, IgA levels of acute phase and recovery phase were significantly lower than the control group, IgM and complement C3 levels in acute stage were significantly higher than the control group, during the recovery period tended to be normal, complement C4 in acute stage levels were significantly higher than those in recovery period and both higher than the control group. The CD3+, CD4+ and CD4/CD8 ratio of MPP in acute stage and recovery phase were significantly lower than the control group, and these numerical indexes of the recovery period were significantly higher than the acute stage, CD8+ levels in acute stage were significantly higher than that in recovery period and both higher than control group. Compared with the control group ,The levels of inflammatory cytokines IL-2 in the acute phase and recovery phase were significantly decreased, and the recovery period was significantly higher than that in acute stage, the test results that the levels of IL-6, TNF-α, IL-8, IL-10 and IL-13 in acute phase and recovery phase were significantly higher than those in control group and the recovery period was significantly lower than that in the acute stage.Conclusion:The body humoral immune function and cellular immune function damage caused by MP infection in infants and young children could lead to the disorder of immune system and the abnormal expression of inflammatory cytokines. Therefore, Therefore, the real-time monitoring the dynamic level of the indicators can define the infants and young children's condition, improve the recovery rate, and have a certain guiding significance of the clinical diagnosis of infants and young children .

Effect of azithromycin combined with terbutaline on the infection and systemic conditions in children with mycoplasma pneumonia

Objective: To study the effect of azithromycin combined with terbutaline on the infection and systemic conditions in children with mycoplasma pneumonia. Methods: A total of 80 children with pneumonia who were treated in the hospital between August 2014 and February 2017 were collected and divided into control group and observation group according to the random number table method, 40 cases in each group. The control group received azithromycin therapy, the observation group received azithromycin combined with terbutaline therapy, and both therapies lasted for 6 d. The differences in systemic inflammatory response, myocardial enzyme spectrum, and liver function and so on were compared between the two groups before and after treatment. Results: Before treatment, differences in serum levels of inflammatory factors, myocardial enzyme spectrum indexes and liver function indexes were not statistically significant between the two groups. After 6 d of treatment, serum IL-2, IL-4, IL-8, IL-13, PCT, CK-MB, LDH, HBDH, ALT, AST and ALP levels of both groups of patients were significantly lower than those before treatment, and serum IL-2, IL-4, IL-8, IL-13, PCT, CK-MB, LDH, HBDH, ALT, AST and ALP levels of observation group were significantly lower than those of control group. Conclusion: Azithromycin combined with terbutaline therapy can effectively control the systemic inflammatory response and protect the heart and liver function in patients with mycoplasma pneumonia.

Preventive Effects of Five Drugs on Mycoplasma Pneumonia of Swine (MPS)

The paper was to explore the preventive effects of five drugs on mycoplasma pneumonia of swine （MPS） and to provide reference for clinical medication of pig farms in Hainan Province. A total of 444 health piglets were randomly divided into 6 groups, including five medication groups （72 piglets in group A, 74 pig- lets in group B, 72 piglets in group C, 76 piglets in group D, 76 piglets in group E） and one control group （74 piglets）. The piglets in experimental groups were treated drugs once a day for successive 5 days at 30, 60, 90, 120 and 150 of age. The piglets in control group were free of medication. At 70 and 140 days of age, 15 piglets of each group were randomly selected to collect their blood sermn. The Mycoplasma hyopneumoniae （M-Hyo） antibodies in serum were measured by en- zyme-linked immunosorbent assay （ELISA）. During the experiment, the incidence rates of respiratory disease, lung lesion, feed conversion rate, average daily gain （ADG）, and mortality rate of pigs were also observed and recorded. The results showed that the five drugs had significant difference in preventative effects. Group C （Zhiyuanjing group） received the best preventive effect and the highest economic benefits. Compared with control group, the ADG and feed conversion rate in group C were increased by 7.53% and 9.09%, respectively; the incidence rate of respiratory disease was reduced by 13.44% and lung lesion was alleviated by 81.43% ; and the earnings of each pig could rise by 132.70 yuan. The preventative effect and economic benefit of the drugs was sequenced by Chansu Kechuanling and Bingchan Kechuanwang. Wante Feilin and amoxicillin had weaker preventive effects against MPS but greatly influenced growth performance of pigs, so they should be used alternatively with other drugs.

Correlation of serum complement and immunoglobulin contents with inflammatory stress response in children with Mycoplasma pneumoniae pneumonia

Objective:To study the correlation of serum complements C3 and C4 as well as immunoglobulins IgM, IgA and IgG contents with inflammatory stress response in children with mycoplasma pneumoniae pneumonia.Methods: The children who were diagnosed with Mycoplasma pneumoniae pneumonia in Xiangyang No. 1 People's Hospital, Hubei University of Medicine between February 2015 and January 2018 were selected as the MPP group, and healthy children who received physical examination during the same period were selected as the control group. The contents of complements, immunoglobulins and inflammatory stress mediators in serum as well as the expression of inflammatory stress molecules in peripheral blood were measured.Results: Serum C3, C4, IgM, sICAM-1, CD40L, HMGB1, Cor and MDA levels as well as peripheral blood TLR2, TLR4, CD11b, CD18, MPO and NOX2 expression intensity of MPP group were significantly higher than those of control group, IgA level was significantly lower than that of control group, and IgG level was not different from that of control group;serum C3, C4 and IgM levels of MPP group were positively correlated with serum sICAM-1, CD40L, HMGB1, Cor and MDA levels as well as peripheral blood TLR2, TLR4, CD11b, CD18, MPO and NOX2 expression intensity, and serum IgA level was negatively correlated with serum sICAM-1, CD40L, HMGB1, Cor and MDA levels as well as peripheral blood TLR2, TLR4, CD11b, CD18, MPO and NOX2 expression intensity. Conclusion: The changes of serum complements and immunoglobulins in children with Mycoplasma pneumoniae pneumonia are related to the excessive activation of inflammatory stress response in the course of disease.

Status of <i>Mycoplasma pneumoniae</i>Pneumonia in Chinese Children: A Systematic Review

Mycoplasma pneumoniae pneumonia (MPP) becomes one of the most important health problems in China recently. Date for MPP inChinais scarce. Although macrolides and/or cortical steroids had been reported to be effective treatment for MPP, the long-term outcome remained uncertain. A study on status of MPP in China was conducted via a systematic review of published studies which have the Chinese data and collected from published PubMed and core journals of China Knowledge Resource Integrated Database (CNKI). The analysis was based on epidemiology, clinical characteristics, treatment, drug resistance and prognosis. Twenty five articles concerned about MPP in Chinese children and adolescent were enrolled, including 11 studies on epidemiology/etiology, 11 studies on clinical characteristics, 7 studies on drug resistance, 5 studies on treatment from China's Mainland respectively. The overall incidence of MPP ranged from 7.1% to 54.4%. Fever and cough were most frequently identified in manifestations. Drug resistance to macrolides ranged from 18.9% to 90%. The outcome of treatment in patients who received combined treatment of macrolides, cephalosporin antibiotics and/or cortical steroid seems to be better than those who received macrolides only. Macrolide combined with cephalosporin or cortical steroid both may decrease the severity of MPP in the past decade. There was not enough evidence to suggest that cortical steroid can decrease the mortality of MPP in children. And a multi-center, randomized double blind research on the effect of cortical steroid was encouraged.

Analysis of knowledge graph based on CiteSpace research on the treatment of pediatric pneumonia with traditional Chinese medicine

Objective:Based on the CiteSpace tool,this study makes a visualization analysis on the treatment of infantile pneumonia with traditional Chinese medicine in the past 20 years,so as to explore the development status,research hotspots and frontier trends of the treatment of infantile pneumonia with traditional Chinese medicine,and provide a reference for the research on the treatment of infantile pneumonia and related diseases with traditional Chinese medicine.Methods:A total of 645 literatures related to the treatment of pediatric pneumonia with traditional Chinese medicine were retrieved from CNKI.The visual atlas was made by year,author,institution and key words,and the co-occurrence,clustering and emergence analysis were performed.Results:The related literatures span from January 2001 to February 2021,and the number of related literatures showed an obvious increasing trend,with an average annual publication of 38 papers.From 2002 to 2014,the increase was the most obvious,and began to show a gentle growth trend in 2015.Twelve main clusters were obtained by keyword cluster analysis.Emergent analysis results in a total of 19 emergent words,which are composed of 439 nodes and 1,452 lines in total.There are different research hotspots in different periods,and in the past five years,the clinical efficacy of traditional Chinese medicine in the treatment of infantile pneumonia and the related research of traditional Chinese medicine characteristic nursing has become a contemporary hot spot.Conclusion:At present,the research on the treatment of children's pneumonia with traditional Chinese medicine shows an increasing trend.There is still a lack of continuity among various studies.The cooperation between the authors and various institutions is low.Moreover,the research direction in this field mainly focuses on children's mycoplasma pneumonia.In addition,the clinical efficacy observation of the combination of traditional Chinese medicine and azithromycin in the treatment of children's pneumonia will become a hot topic in the future.In addition to the research focus in this field,the clinical efficacy of TCM(traditional Chinese medicine)in the treatment of infantile pneumonia and the characteristic nursing of traditional Chinese medicine may still become one of the hot spots in the future.

Involvement of TLR2 and TLR4,Chlamydophila pneumoniae and Mycoplasma pneumoniae in adventitial inflammation of aortic atherosclerotic aneurysm

Aortic atherosclerotic aneurysm (AAA) is associated with adventitial inflammation where infection is suggested to have a role. Co-infection with Chlamydophila pneumoniae (Cp) and Mycoplasma pneumoniae (Mp) was linked with coronary plaque rupture, in association with vessel dilatation and adventitial inflammation. Pathogens are recognized by Toll-like receptors (TLRs) development of the inflammatory process. Objective: Here, we studied whether co-infection by Cp and Mp was involved in the increased inflammation present in AAA and if it could be associated with deficient expression of TLRs. We compared human samples of AAA with non-dilated human aortic atherosclerotic lesions, regarding the amount of Cp and Mp antigens, and expression of TLR2 and TLR4. Methods: Two groups of aorta fragments were analyzed: G1 (n = 13) moderate atherosclerosis and G2 (n = 14) AAA samples, through immunohisto-chemistry and in situ hybridization methods. Results: Mp and Cp antigens in intima/medial layer were greater in G2 than G1, with no difference in adventitia. TLR2 and TLR4 were higher in G2 than G1 adventitia fat. There was a correlation between Mp versus TLR2 and of TLR4 in intima/medial layer and in adventitia of G1, but there was a lack of correlation in G2. In Cp adventitia, the correlation in G1 was high with TLR2 but not with TLR4, and in G2 the correlation was positive for both TLRs. Conclusion: This study favors the concept that symbiotic co-infection by Cp and Mp participates in the pathogenesis of AAA. It also emphasizes that adventitial fat is the initial site for colonization of these bacteria that probably reach the tissue through vasa vasorum. An exacerbated immune reaction is not efficient to control the infection that reaches and proliferates in high levels at the medial and intimal layer, contributing to the development of vessel dilatation.

Evaluation of a New Real-time PCR Assay for Detection of Mycoplasma Pneumoniae in Clinical Specimens

Objective To establish and evaluate a real-time PCR assay to detect Mycoplasma pneumoniae （M.pneumoniae） in clinical specimens. Methods By analysing the whole pl gene sequence of 60 M.pneurnoniae clinical isolates in Beijing of China, an optimized real-time PCR assay （MpP1） using pl gene conserved region was designed. The specificity and sensitivity of this assay were evaluated and compared with other two reported assays （RepMpl and Mp181） using 40 positive and 100 negative clinical specimens. Results The detection limit of the new assay was 8.1 fg （about 1-3CFU） M.pneumoniae DNA. The sensitivity of MpP1, RepMpl, and Mp181 assays appeared to be 100%, 100%, and 85%, respectively. Conclusion MpP1 assay is suitable for the detection of M.pneumoniae in Chinese clinical specimens.

Mycoplasma pneumoniae Macrolide Resistance and MLVA Typing in Children in Beijing,China,in 2016:Is It Relevant?

Objective The aim of this study is to investigate the macrolide resistance rate and molecular type with multiple-locus variable-number tandem-repeat analysis(MLVA)of Mycoplasma pneumoniae of Beijing in 2016 in pediatric patients.Methods Real-time quantitative polymerase chain reaction(PCR)was used to identify M.pneumoniae,and MLVA was performed.The domain V of the 23 S rRNA was sequenced to detect macrolide-resistant point mutations.We also investigated the activities of antibiotics against M.pneumoniae isolates in vitro.Results The PCR detection rate of M.pneumoniae in children in Beijing was 40%,and the macrolide resistance rate was 66%.The A2063 G mutation in the 23 S rRNA V region is the dominant mutation(137/146,93.84%),whereas the A2064 G mutation is rare(9/146,6.16%).Seventy-three samples were typed successfully by MLVA typing,including 86.3%(63/73)were MLVA type 4-5-7-2,and 13.7%(10/73)were MLVA type 3-5-6-2.No other types were found.No strains were resistant to levofloxacin or tetracycline.Conclusion In 2016,a specific decrease in the macrolide resistance rate occurred in Beijing.The detection rate and macrolide resistance rate of outpatients are lower than those of inpatients.The A2063 G mutants M.pneumoniae have high levels of resistance to erythromycin and azithromycin.The primary MLVA type is 4-5-7-2,followed by 3-5-6-2.No other MLVA types were detected.No strains resistant to tetracycline or levofloxacin were found in vitro.