Mucositis sin rash inducida por Mycoplasma pneumoniae, primer reporte de caso en Perú / Rashless mucositis induced by Mycoplasma pneumoniae. First case reported in Peru

Introducción: Mycoplasma pneumoniae es una bacteria de distribución mundial que comúnmente ocasiona infecciones respiratorias en forma de traqueobronquitis y neumonía atípica, recientemente se ha descrito como etiología de una enfermedad denominada Mycoplasma-induced rash and mucositis. Caso clínico: Varón de 11 años, procedente del departamento de Tacna en Perú que se presentó con cuatro días de enfermedad caracterizado por fiebre, tos, disnea, conjuntivitis bilateral purulenta y lesiones erosivas muy dolorosas en mucosa yugal, lengua y labios, recibió tratamiento antibiótico, antiviral y antifúngico, evolucionando favorablemente. Se confirmó infección por Mycoplasma pneumoniae mediante serología IgM por ELISA. De nuestro conocimiento, este es el primer caso de Mucositis sin rash inducido por Mycoplasma pneumoniae reportado en Perú, el reconocimiento temprano de este síndrome permitirá un tratamiento más específico, evitando la restricción de fármacos apropiados(AU)

Introduction: Mycoplasma pneumoniae is a bacterium of worldwide distribution which commonly causes respiratory infections such as tracheobronchitis and atypical pneumonia. It has recently been described as etiology of a disease called Mycoplasma pneumoniae-induced rash and mucositis. Objective: Present the first known report of Mycoplasma pneumoniae-associated mucositis in Peru, diagnosed by compatible clinical picture and confirmed by serology. Clinical case: A male 11-year-old patient from the Tacna Region in Peru presented with a clinical state of four days' evolution characterized by fever, coughing, dyspnea, bilateral purulent conjunctivitis and very painful erosive lesions on the jugal mucosa, tongue and lips. The patient received antibiotic, antiviral and antifungal treatment, to which he responded favorably. Mycoplasma pneumoniae infection was confirmed by IgM ELISA serology. Conclusions: Early recognition of this syndrome will lead to a more specific treatment, avoiding the restriction of appropriate drugs(AU)

Comparison of Mycoplasma pneumoniae IgM and IgE Antibody Levels in Asthmatic and Non-Asthmatic Adults.

OBJECTIVE: Mycoplasma pneumoniae (M. pneumoniae), an extracellular pathogen lacking a cell wall, causes respiratory infection in adults and children and has been implicated in asthma exacerbation; immunoglobulin (Ig) E may be involved in these exacerbations. Specific IgM and IgG immune response to M. pneumoniae has been reported, but less is known about IgE M. pneumoniae antibody (Ab) responses in asthma. Previous studies in our laboratory demonstrated that asthmatic children have increased IgM M. pneumoniae levels, but not IgE. Thus, we sought to investigate whether past M. pneumoniae infection triggers production of M. pneumoniae-specific IgE Abs in adult subjects with/without asthma. METHODS: M. pneumoniae- IgE and -IgM Ab responses were studied in adult asthmatic (N=22) and non-asthmatic (N=22) subjects (ELISA). Data are reported as antibody index. Threshold detection levels: IgE, IgM: 0.2, 0.9, respectively. RESULTS: M. pneumoniae-IgE Ab levels were low and below the threshold of detection in both asthmatic and non-asthmatics (0.002±0.008 vs. 0.02±0.03; P=0.021). However, specific-IgM levels were slightly higher in non-asthmatics compared with asthmatics (0.96±0.37 vs. 0.79±0.31; P=0.054). M. pneumoniae-IgM Ab positivity was similar in both groups (P=1.0). CONCLUSION: IgM M. pneumoniae Abs may play an important role in non-asthma and persist for months after acute infection. IgE M. pneumoniae Abs may play a less important role in both groups.

The risk factors of children acquiring refractory mycoplasma pneumoniae pneumonia: A meta-analysis.

OBJECTIVES: Refractory mycoplasma pneumoniae pneumonia (RMPP) in children has been increasing worldwide. In this study, we conducted a meta-analysis to generate large-scale evidence on the risk factors of RMPP to provide suggestions on prevention and controlling for children. METHODS: Web of Science, PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, and Wanfang (Chinese) were searched to identify relevant articles. All analyses were performed using Stata 14.0. RESULTS: We conducted a meta-analysis of 15 separate studies. Fever for more than 10 days (odds ratio [OR] 3.965, 95% confidence interval [CI] 2.109-7.456), pleural effusion (OR 6.922, 95% CI 2.058-23.282), extra-pulmonary complications (OR 17.762, 95% CI 11.146-28.305), pulmonary X-ray consolidation ≥2/3 (OR 8.245, 95% CI 1.990-34.153), CRP >40 mg/L (OR 4.975, 95% CI 2.116-11.697) were significantly related to the risk of RMPP. We did not find an association between male sex (OR 0.808, 95% CI 0.548-1.189), LDH >410IU/L (OR 1.033, 95% CI 0.979-1.091) and the risk of RMPP. CONCLUSIONS: Fever for more than 10 days, pleural effusion, extra-pulmonary complications, pulmonary X-ray consolidation≥ 2/3 and CRP >40 mg/L are risk factors for early evaluation of RMPP.

The clinical characteristics and risk factors for necrotizing pneumonia caused by Mycoplasma pneumoniae in children.

BACKGROUND: The incidence of necrotizing pneumonia (NP) caused by Mycoplasma pneumoniae (MP) is increasing. We analyzed the clinical characteristics and the risk factors for NP caused by MP. METHODS: A retrospective observational study was conducted in 37 patients with NP caused by MP (NP group) and 74 patients diagnosed with lobar M. pneumoniae pneumonia with no necrosis (control group) who were admitted to our hospital between January 2013 and December 2017. The clinical manifestations, laboratory data, imaging findings, treatments and outcomes were analyzed. RESULTS: The proportion of females, the incidence of pleural effusion, fever duration, hospitalization days, white blood cell count, neutrophil ratio, D-dimer level and use of other types of antibiotics were higher in the NP group than in the control group (P < 0.05). The control group exhibited a greater use of low molecular weight heparin (LMWH) than the NP group (P < 0.05). According to the multivariate logistic regression analysis, a white blood cell count > 12.3 × 109/L (Odds ratio, OR = 6.412), a neutrophil ratio > 73.9% (OR = 6.081) and D-dimer level > 1367.5 ng/mL (OR = 8.501) were risk factors for pulmonary necrosis caused by MP. Furthermore, the use of LMWH (OR = 0.074) reduced the risk of pulmonary necrosis. CONCLUSIONS: NP is a rare complication of severe Mycoplasma pneumoniae pneumonia (SMPP), and although the clinical course is longer than common MP infection, the necrotic area is absorbed gradually. In patients with SMPP presenting with lobar consolidation, a white blood cell count > 12.3 × 109/L, a neutrophil ratio > 73.9% and D-dimer level > 1367.5 ng/mL are risk factors for pulmonary necrosis, and the use of LMWH reduces the risk of pulmonary necrosis.

Impact of air pollutants on pediatric admissions for Mycoplasma pneumonia: a cross-sectional study in Shanghai, China.

BACKGROUND: Children are especially vulnerable to pneumonia and the effects of air pollution. However, little is known about the impacts of air pollutants on pediatric admissions for Mycoplasma pneumonia. This study was conducted to investigate the impacts of air pollutants on pediatric hospital admissions for Mycoplasma pneumonia in Shanghai, China. METHODS: A cross-sectional design was applied to explore the association between pediatric hospital admissions and levels of air pollutants (fine particulate matter, particulate matter, ozone, sulfur dioxide, nitrogen dioxide, and carbon monoxide). Data on hospital admissions for pneumonia and levels of ambient air pollutants were obtained for the period of 2015 to 2018. Associations between pediatric admissions for Mycoplasma pneumonia and ambient air pollutants were calculated using logistic regression and described by the odds ratio and relevant 95% confidence interval. The hysteresis effects of air pollutants from the day of hospital admission to the previous 7 days were evaluated in single-pollutant models and multi-pollutant models with adjustments for weather variables and seasonality. Lag 0 was defined as the day of hospital admission, lag 1 was defined as the day before hospital admission, and so forth. RESULTS: In the single-pollutant models (without adjustment for other pollutants), pediatric hospital admissions for pneumonia were positively associated with elevated concentrations of nitrogen dioxide and fine particulate matter. A 0.5% increase in daily admissions per 10-µg/m3 increase in the nitrogen dioxide level occurred at lag 1 and lag 2, and a 0.3% increase in daily admissions per 10-µg/m3 increase in fine particulate matter occurred at lag 1. In the multi-pollutant models, nitrogen dioxide and fine particulate matter remained significant after inclusion of particulate matter, ozone, sulfur dioxide, and carbon monoxide. CONCLUSIONS: This study illustrated that higher levels of nitrogen dioxide and fine particulate matter increase the risk of pediatric hospitalization for Mycoplasma pneumonia in Shanghai, China. These findings imply that the high incidence of Mycoplasma pneumonia in children in Asia might be attributed to the high concentration of specific air pollutants in Asia.

Respiratory pathogens and acute chest syndrome in children with sickle cell disease.

BACKGROUND: Acute chest syndromes (ACS) may be associated with upper respiratory tract infections, but the epidemiology of viral and intracellular respiratory pathogens in children with sickle cell disease (SCD) is not precisely known. The aim of this study was to describe the epidemiology of viral and intracellular respiratory pathogens in children with SCD presenting with fever and/or ACS. MATERIALS AND METHODS: An observational, prospective, single-centre cohort study with nested case-control analysis was conducted on children with SCD admitted from October 2016 to October 2017 for fever and/or ACS to the paediatric department of Robert Debré university hospital, Paris, France. They were screened for 20 respiratory pathogens by a multiplex PCR in the nasopharynx (FilmArray). RESULTS: We included 101 children. M/F sex ratio of 0.45. The median age was 3.2 years (IQR: 1.4-8.2). At least one pathogen was isolated in 67 patients (67%). The most frequent viruses were as follows: rhinovirus (n=33), adenovirus (n=14), respiratory syncytial virus (n=13) and parainfluenza viruses (n=11). Mycoplasma pneumoniae was detected in one case. Twenty-three (23%) presented with or developed ACS. A nested case-control analysis was performed, after pairing ACS with non-ACS children for age and inclusion period. There was no statistical association between any viral detection or multiple viral infection, and ACS (p=0.51) even though parainfluenza viruses were twice as common in ACS. CONCLUSIONS: Viral detection in febrile children with SCD is frequent, but its association with ACS was not demonstrated. In this study, M. pneumoniae was rare in young children with SCD experiencing ACS.

Annual and seasonal patterns in etiologies of pediatric community-acquired pneumonia due to respiratory viruses and Mycoplasma pneumoniae requiring hospitalization in South Korea.

BACKGROUND: Community-acquired pneumonia (CAP) is one of the leading worldwide causes of childhood morbidity and mortality. Its disease burden varies by age and etiology and is time dependent. We aimed to investigate the annual and seasonal patterns in etiologies of pediatric CAP requiring hospitalization. METHODS: We conducted a retrospective study in 30,994 children (aged 0-18 years) with CAP between 2010 and 2015 at 23 nationwide hospitals in South Korea. Mycoplasma pneumoniae (MP) pneumonia was clinically classified as macrolide-sensitive MP, macrolide-less effective MP (MLEP), and macrolide-refractory MP (MRMP) based on fever duration after initiation of macrolide treatment, regardless of the results of in vitro macrolide sensitivity tests. RESULTS: MP and respiratory syncytial virus (RSV) were the two most commonly identified pathogens of CAP. With the two epidemics of MP pneumonia (2011 and 2015), the rates of clinical MLEP and MRMP pneumonia showed increasing trends of 36.4% of the total MP pneumonia. In children < 2 years of age, RSV (34.0%) was the most common cause of CAP, followed by MP (9.4%); however, MP was the most common cause of CAP in children aged 2-18 years of age (45.3%). Systemic corticosteroid was most commonly administered for MP pneumonia. The rate of hospitalization in intensive care units was the highest for RSV pneumonia, and ventilator care was most commonly needed in cases of adenovirus pneumonia. CONCLUSIONS: The present study provides fundamental data to establish public health policies to decrease the disease burden due to CAP and improve pediatric health.

The role of miR-29c/B7-H3/Th17 axis in children with Mycoplasma pneumoniae pneumonia.

BACKGROUND: Mycoplasma pneumoniae (M. pneumoniae) is one of the most common causes of community-acquired pneumonia in children. Recent studies demonstrated that the incidence of severe or fatal M. pneumoniae was gradually increasing, which may be related to the excessive inflammation. However, the exact pathogenesis of excessive inflammation in Mycoplasma pneumoniae pneumonia(MPP) is still unclear. This study aimed to reveal the role of miR-29c/B7-H3/Th17 axis in children with MPP. METHODS: Children hospitalized in Respiratory Department during Jan. 2014 to Dec. 2015 were enrolled. All children enrolled was confirmed with MP infection using real-time PCR and ELISA. Children were excluded if they were co-infected with other pathogens. A total of 52 children with MPP and 26 controls were enrolled. miR-29c expression in monocytes of children with MPP was determined by real-time PCR and soluble B7-H3 (sB7-H3) and IL-17 were determined by ELISA, and explore their clinical significance. miR-29c overexpression and silencing technology and luciferase reporter assay were performed to confirm whether B7-H3 is the direct target of miR-29c. The levels of transcription factor ROR-γt in CD4+ T cells and cytokine IL-17A in supernatant were detected after stimulated by different concentrations of B7-H3 fusion protein in vitro. RESULTS: Of all 52 children with MPP, the mean age of the children were 77 ± 33 months, and 23 cases were male accounting for 44.2%. Nineteen cases had pleural effusion accounting for 36.5%. Children with MPP had significantly lower level of miR-29c and higher level of sB7-H3 and IL-17 compared to controls (both P < 0.05). The level of miR-29c significantly increased during convalescent phase compared to that of acute phase while sB7-H3 and IL-17 significantly decreased during convalescent phase (both P < 0.05). There was a positive correlation between the level of sB7-H3 and IL-17 in children with MPP during acute-stage (r = 0.361,P = 0.009). Children with MPP combined with pleural effusion had significantly higher level of sB7-H3 compared to those without pleural effusion (9952.3 ± 3065.3 vs. 7449.7 ± 2231.5, pg/ml), and the levels of sB7-H3 was positively correlated with the number of days of fever. The level of miR-29c was negatively correlated with M. pneumoniae specific IgG, IgM level. High concentrations of B7-H3(15µg/ml) could enhance ROR-γt expression and increase IL-17A. Functional studies based on luciferase reporter assay and immunofluorescence staining suggested that B7-H3 is the direct target of miR-29c, and miR-29c silencing or overexpression could up- or down-regulate the expression of B7-H3 in THP-1 cells. CONCLUSIONS: The axis of miR-29c/B7-H3/Th17 plays a vital role in children with MPP through excessive inflammation. miR-29c and B7-H3 may be the new target for the prevention and treatment of MPP, and may be the novel and potential biomarkers for the assessment of prognosis.

Impact of atopy on the severity and extrapulmonary manifestations of childhood Mycoplasma pneumoniae pneumonia.

OBJECTIVES: The impact of atopy on disease severity and extrapulmonary manifestations in children with Mycoplasma pneumoniae (MP) pneumonia is unknown. METHODS: Patients diagnosed with MP pneumonia between January 2016, and December 2017, were enrolled in this study. A total of 150 MP pneumonia patients were enrolled at diagnosis and divided into the atopic group (n = 48) and the nonatopic group (n = 102). Furthermore, these patients were also assessed after being divided into the pulmonary group (n = 120) and the extrapulmonary group (n = 30). Clinical characteristics, respiratory disease severity, any allergy history, and specific allergen sensitizations were collected from all patients. The serum interleukin-17 (IL-17) and total immunoglobulin E (lgE) levels were also measured. RESULTS: More children in the atopic group than those in the nonatopic group presented with severe MP pneumonia, tachypnea, oxygen therapy, steroid treatment, atopic conditions including asthma attack, a previous history of asthma, decreased IL-17 levels, and increased IgE levels (all P < 0.05). When compared with those in the pulmonary group, the patients in the extrapulmonary group showed higher percentages of atopy, higher total lgE levels, and lower IL-17 levels (all P < 0.05). CONCLUSIONS: Atopy may be a risk factor for disease severity and extrapulmonary manifestations in children with MP pneumonia.

Therapeutic efficacy of azithromycin, clarithromycin, minocycline and tosufloxacin against macrolide-resistant and macrolide-sensitive Mycoplasma pneumoniae pneumonia in pediatric patients.

OBJECTIVE: To clarify therapeutic effects of azithromycin, clarithromycin, minocycline and tosufloxacin against macrolide-resistant Mycoplasma pneumoniae (MRMP) pneumonia and against macrolide-sensitive Mycoplasma pneumoniae (MSMP) pneumonia in pediatric patients. METHODS: A prospective, multicenter observational study was conducted from July 2013 to August 2015. The therapeutic effects of azithromycin, clarithromycin, minocycline and tosufloxacin were evaluated in 59 patients with pneumonia caused by MRMP and in 50 patients with pneumonia caused by MSMP. In vitro activities of antimicrobial agents against isolates of Mycoplasma pneumoniae were also measured. RESULTS: Mean durations of fever following commencement of treatment in patients infected with MRMP and MSMP were 5.2 and 1.9 days, respectively (log-rank test, P < 0.0001). Among patients infected with MRMP, mean durations of fever were 4.6, 5.5, 1.0 and 7.5 days for patients treated with azithromycin, clarithromycin, minocycline and tosufloxacin, respectively (log-rank test, P < 0.0001). Among patients infected with MSMP, mean durations of fever were 2.5, 1.7, 0.9 and 4.3 days for patients treated with azithromycin, clarithromycin, minocycline and tosufloxacin, respectively (log-rank test, P = 0.0162). The MIC90s of azithromycin and clarithromycin among the 27 isolates of MRMP were 64 and 256 µg/ml, respectively, and those among the 23 isolates of MSMP were <0.000125 and 0.001 µg/ml, respectively. The MIC90s of minocycline and tosufloxacin among the 27 isolates of MRMP were 1.0 and 0.25 µg/ml, respectively, and those among the 23 isolates of MSMP were 1.0 and 0.5 µg/ml, respectively. CONCLUSION: Both minocycline and tosufloxacin showed good in vitro activities against MRMP. Minocycline, but not tosufloxacin, shortened the duration of fever in pediatric patients infected with MRMP compared to the duration of fever in patients treated with macrolides.

Role of anti-inflammatory cytokines in pathogenesis of pediatric mycoplasma pneumoniae pneumonia.

Through detection and analysis of the changes of interleukin (IL)-2 and IL-10 in children with mycoplasma pneumoniae pneumonia (MPP), this study aimed to explore the role of cytokines in the pathogenesis of pediatric MPP as well as immunological pathogenesis of MPP, to provide guidance for clinical diagnosis, assessment and treatment of MPP. Enzyme linked immunosorbent adsorption (ELISA) analysis was applied to determine the expression level of IL-2 and IL-10 in serum. According to the experimental results, we found that the expression levels of IL-2 and IL-10 changed significantly in different phases of MPP in comparison with a healthy control group and a case control group. The expression levels of IL-2 and IL-10 can be used as an important indicator for early diagnosis of MPP. Accordingly, detection of IL-2 and IL-10 is of great significance to the diagnosis of MPP and studies on their roles can provide guidance for treatment.

[Serum tumor necrosis factor-α, interleukin -6 and galctin-3 concentrations in children with Mycoplasma pneumoniae pneumonia].

OBJECTIVE: To study the changes in serum tumor necrosis factor-α (TNF- α), interleukin-6 (IL-6) and galctin-3 (Gal-3) concentrations in children with Mycoplasma pneumoniae pneumonia (MPP), and their roles in MPP. METHODS: Serum TNF-α, IL-6 and Gal-3 concentrations were measured using double antibody sandwich ELISA in 48 children with acute MPP (severe: 21 cases; mild: 27 cases) and in 30 healthy children (control group). RESULTS: Serum concentrations of TNF-α, IL-6 and Gal-3 in both the severe and mild groups were significantly higher than in the control group before treatment. The concentrations of the three indexes in the severe group were significantly higher than in the mild group. Serum concentrations of the three indexes decreased significantly after treatment in both groups. CONCLUSIONS: Serum TNF-α, IL-6 and Gal-3 play important roles in the occurrence and development of pediatric MPP and their levels are associated the severity of this disorder.

[Analysis of 11 cases of mycoplasma pneumoniae infection combined with Kawasaki disease].

OBJECTIVE: To study the clinical characteristics of pediatric Kawasaki disease complicating mycoplasma pneumoniae pneumonia. METHODS: Retrospective analysis was conducted on 11 children who had been diagnosed with Kawasaki disease with Mycoplasma pneumoniae pneumonia. RESULTS: The 11 cases presented with varying degrees of fever, conjunctival congestion, skin rashes, lymphadenectasis, distal extremities lesions, heart and lung lesions. 8 of them were standartly treated with azithromycin, while 3 of them were treatad with azithromycin and erythromycin. 2 patients with pleural effusion complicated by lobar pneumonia consolidation were treated with gamma globulin combined aspirin. All of the 11 patients were healed. CONCLUSION: Infections are common at the diagonosis of KD. Reasonable examination and antibiotics is useful to cure KD with MPP.

Etiology and factors contributing to the severity and mortality of community-acquired pneumonia.

OBJECTIVE: Community-acquired pneumonia (CAP) remains a major cause of death. No studies have reported the use of rapid influenza diagnostic tests (RIDT) for the etiological diagnosis, and the factors contributing to severity and mortality have not yet been fully investigated. The aim of this study was to review the etiologies of CAP using RIDT and to identify risk factors related to the severity and mortality of the disease. METHODS: This retrospective study assessed these factors in hospitalized patients, with special emphasis on microbial etiology. RESULTS: A total of 1,032 patients aged 63.9±18.3 years were studied, 66.2% of whom were men. Microbial identification was obtained in 57.0% of the cases. The most frequent causative microbial agents were Streptococcus pneumoniae, Mycoplasma pneumoniae and the influenza virus, and the second most frequent pathogens in the patients with severe CAP and the non-survivors were S. pneumoniae and the influenza virus. Age (≥65 years), chronic obstructive pulmonary disease, congestive heart failure, diabetes mellitus, dementia and Legionella spp. infection and polymicrobial infection were each found to be independent factors related to severity in the multivariate analysis, whereas "unidentified pathogen" was found to be an independent factor for non-severe CAP. Age (≥65 years), chronic pulmonary aspergillosis, post-lung cancer surgery and severe CAP were found to be independent factors for non-survival according to a multivariate analysis. CONCLUSION: In addition to S. pneumoniae, the influenza virus was a frequent cause of CAP overall and a frequent causative pathogen in both severe cases of CAP and non-survivors. Legionella spp. infection and polymicrobial infection were found to be an independent factor for the severity of CAP along with advanced age and certain comorbidities. An advanced age, certain respiratory comorbidities and severe CAP were found to be important independent factors for the mortality of CAP.

An outbreak of Mycoplasma pneumoniae caused by a macrolide-resistant isolate in a nursery school in China.

Eighteen out of 45 children were reported to have a respiratory illness during an outbreak at a temporary dormitory in a nursery school in China in 2011. To study the outbreak and to determine the risk factors for infection, an epidemiological investigation was performed. A standardized questionnaire was completed for a total of 45 children with the help of their guardians and parents. In addition, acute- and convalescent-phase serum samples and throat swabs from the children were taken for laboratory diagnosis. The diagnosis of a Mycoplasma-like illness was based on the following clinical criteria. The criteria were onset of illness after 31 May 2011, characterized by a cough, fever(>37.5 °C), or at least 3 of the following symptoms: fever, sore throat, cough or expectoration, and runny or stuffy nose. PCR-restriction fragment length polymorphism (PCR-RFLP), determination of MICs, and sequencing were performed to determine the genotype, antibiotic resistance, and sequence polymorphisms of the isolated strains, respectively. The paired sera revealed that 15 patients were infected with Mycoplasma pneumoniae. Epidemiology confirmed that this was a point source outbreak, characterized by a short incubation period, a high secondary attack rate, and a long period of hospitalization. PCR-RFLP analysis revealed that the 12 isolated strains of M. pneumoniae shared the same subtype P1 gene, and 23S rRNA sequence analysis showed that these strains harbored two macrolide-resistant gene-related point mutations at position 2063 and 2617. In this outbreak, the major risk factor was the distance between the bed of the first patient and the beds of close contacts (beds less than three meters apart). The strains isolated in this study were found to harbor two point mutations conferring macrolide resistance, indicating the importance of pathogen and drug resistance surveillance systems.

[Levels of TNF-α, IL-6 and IL-10 in bronchoalveolar lavage fluid in children with Mycoplasma pneumoniae pneumonia].

OBJECTIVE: To study the levels and roles of cytokines TNF-α, IL-6 and IL-10 in bronchoalveolar lavage fluid (BALF) in children with Mycoplasma pneumoniae pneumonia (MPP). METHODS: The levels of TNF-α, IL-6 and IL-10 in BALF were measured using ELISA in children with MPP at acute stage (n=45) and at remission stage (n=30). Twenty children without lung lesions severed as the control group. RESULTS: The TNF-α, IL-6 and IL-10 levels in BALF were higher in children with MPP at acute stage than those in the control group (P<0.05). The levels of TNF-α and IL-6 in BALF at remission stage were reduced to the levels similar to the control group and were significantly lower than those at the acute stage in children with MPP. However, the levels of IL-10 in BALF remained at higher levels at remission stage in children with MPP. CONCLUSIONS: The levels of TNF-α, IL-6 and IL-10 in BALF increase in children with MPP at acute stage, suggesting that the cytokines may be involved in the pathogenesis of MPP.

The first atypical pneumonia: the history of the discovery of Mycoplasma pneumoniae.

The subject of atypical pneumonias is of great medical and historical interest to modern physicians. Although these diseases have no doubt affected humans throughout our history, it is not until the mid-twentieth century that physicians first began to differentiate certain atypical pulmonary infectious processes from typical pneumonia. Physicians at the time were unclear as to the precise etiology of these infections. As time progressed and study of these organisms continued, physicians were better able to identify the causative agent and devise tests with which to detect the disease. This article focuses on the description and ultimate identification of Mycoplasma pneumoniae.

Deficient immune response to Mycoplasma pneumoniae in childhood asthma.

Prospective studies have suggested that some individuals have a persistent IgM response to Mycoplasma pneumoniae infection with relatively little IgG production over many months. Persistence of the organism in patients with an allergic phenotype might predispose to the development of asthma. This study was designed to analyze the prevalence of M. pneumoniae infection and the immune response to that infection among children with asthma compared with controls. A prospective study was performed in 82 children with physician-diagnosed asthma and 98 nonasthmatic controls over a 5-year period comparing them for evidence of current or prior infection by M. pneumoniae using serology (IgG and IgM), culture, and polymerase chain reaction (PCR), and in vitro cellular responses to M. pneumoniae antigen. Similar numbers of controls (9/98) and asthmatic children (6/82) were PCR(+) for M. pneumoniae at some time during the study. IgM antibody to M. pneumoniae was detected in similar numbers of controls (21/98) and asthmatic children (18/82), but positive IgG antibody titers were detected in significantly more controls (13/98) than asthmatic children (3/82; p = 0.03). Similar numbers from each group were IgM(+) on more than one annual visit (9/98 controls and 7/82 asthmatic children). Antigen-driven proliferation and interferon (IFN) gamma production by mononuclear cells from IgM(+) controls were significantly greater than that of IgM(-) controls, but there was no difference in proliferation and IFN-gamma production by cells from IgM(+) and IgM(-) asthmatic children. These results suggest that asthmatic children have deficient cellular and humoral responses to M. pneumoniae infection compared with nonasthmatic controls.

[Case of multiple pulmonary arteriovenous fistulas detected during treatment for severe pneumonia].

A 55-year-old woman who developed severe hypoxemia associated with severe pneumonia was admitted to our hospital for mechanical ventilation. She was treated with antibiotics under a diagnosis of mycoplasma pneumonia. Although most clinical findings improved, hypoxemia remained. As a chest CT film showed multiple nodules and an enhanced CT film revealed arterial filling in the nodules, multiple pulmonary arteriovenous fistulas (PAVFs) were considered to be an underlying cause of hypoxemia. Transcatheter coil embolization for 5 PAVFs, significantly ameliorated hypoxemia in the patient. PAVF is a congenital desease, and in many cases, is asymptomatic. Therefore, it was rare for PAVFs to be detected in a middle-aged patient with prolonged hypoxemia associated with pneumonia.