Seroprevalencia de anticuerpos anti-Mycoplasma pneumoniae en niños menores de 12 años / Seroprevalence of anti-Mycoplasma pneumoniae antibodies in otherwise healthy children

Resumen: Introducción: La infección por Mycoplasma pneumoniae (Mypn) podría estar ocurriendo a edades más tempranas, debido a fenómenos sociales como concurrencia a centros de cuidado diurno en forma más frecuente y precoz. Objetivo: estimar la prevalencia de anticuerpos anti-Mypn en niños de 0-12 años, y explorar si la edad, asistencia a centro de cuidados diurnos/escuela, hacinamiento o convivencia con niños incrementan el riesgo de seropositividad. Pacientes y Método: Estudio transversal incluyendo niños de 0-12 años de edad que requirieron extracciones de sangre para control, por lo demás sanos. En todos los casos se consignaron las variables mencionadas y se determinó IgG anti-Mypn mediante enzimoinmunoanálisis. Se evaluó la asociación entre predictores y seropositividad en un modelo de regresión logística. Resultados: Se incluyeron 232 pacientes (edad promedio 56,4 ± 40,0 meses). El 56,9% concurría a centro de cuidado diurno/escuela, 63,8% convivían con menores de 12 años y 15,9% presentaban hacinamiento. El 14,6% presentaba anticuerpos anti-Mypn. Los niños seroposi- tivos no mostraron diferencias significativas con aquellos seronegativos en relación a edad (63,1 ± 40,7 vs. 55,4 ± 41,3 meses), escolaridad (64,7% vs 55,5%), hacinamiento (14,7% vs 14,9%), ni con vivencia con menores (64,7% vs 63,6%). La edad tampoco se mostró como predictor independiente de seropositividad en el modelo multivariado. Conclusión: La prevalencia de anticuerpos anti-Mypn fue 14,6%. La edad no fue predictor de seropositividad.

Abstract: Introduction: Mycoplasma pneumoniae (Mypn) infection could be occurring at an earlier age due to social pheno mena such as attending daycare centers more frequently and earlier than decades ago. Objective: to estimate the prevalence of anti-Mypn antibodies in children aged 0-12 years, and to explore whether age, attendance to daycare center/school, overcrowding or the presence of children aged below 12 years in the households increase the risk of seropositivity. Patients and Method: Cross-sectional stu dy including healthy children aged 0-12 years which required blood draws for routine laboratory tests. In all cases, the aforementioned variables were recorded and anti-Mypn IgG was determined by enzyme immunoassay. The association between predictors and seropositivity was assessed in a logistic regression model. Results: We included 232 patients (average age 56.4 ± 40.0 months). 56.9% attended a daycare center/school, 63.8% co-habited with children under 12 years old, and 15.9% lived in overcrowded households. The prevalence of anti-Mypn antibodies was 14.6%. There were no significant differences between seropositive and seronegative children regarding age (63.1 ± 40.7 vs. 55.4 ± 41.3 months), school/day-care attendance (64.7% vs. 55.5%), overcrowding (14.7% vs. 14.9%), or co-habiting with children (64.7% vs. 63.6%). Age was not an independent predictor of seropositivity in the multivariate model. Conclusion: The prevalence of anti-Mypn antibodies in children was 14.6% and age was not a predictor of seropositivity.

The epidemiology and clinical features of Mycoplasma pneumoniae infection in neonates

Abstract Objectives This retrospective study was aimed to explore the epidemiological and clinical profiles of Mycoplasma pneumoniae infection in neonates. Methods From 2011 to 2014, 1322 hospitalized neonates with lower respiratory tract infections were screened for Mycoplasma pneumoniae by detection of Mycoplasma pneumoniae antibodies using Serion ELISA classic Mycoplasma pneumoniae kits. Results Mycoplasma pneumoniae was identified in 89 (6.7%) patients. The age ranged from 1 day to 28 days with a median of 22 days. The male to female ratio was 1.15:1. Mycoplasma pneumoniae infection peaked in spring (from March through May) and winter (from December through February). Compared with non-Mycoplasma pneumoniae infected neonates, those with Mycoplasma pneumoniae infection were older, presented fever more frequently, and had less tachypnea. Conclusions Mycoplasma pneumoniae could be an important etiologic agent for respiratory tract infection in neonates. In neonates Mycoplasma pneumoniae infection was usually associated with older age, presence of fever, and less tachypnea. Mycoplasma pneumoniae infection in neonates tends to be a mild process.

Clinical significance of different bacterial load of Mycoplasma pneumoniae in patients with Mycoplasma pneumoniae pneumonia

OBJECTIVE: This retrospective study was conducted to investigate the clinical significance of differentMycoplasma pneumoniae bacterial load in patients with M. pneumoniae pneumonia (MP) in children. METHODS: Patients with MP (n=511) were identified at the Children's Hospital Affiliated to Soochow University database during an outbreak of MP between January 2012 and February 2013. RESULTS: Comparing patients with high and low bacterial load those with higher loads were significantly older (p<0.01) and had fever significantly more frequently (p=0.01). Presence of wheezing at presentation was associated with low bacterial load (p=0.03). Baseline positive IgM was present in 93 (56.4%) patients with high bacterial load compared to 46 (27.8%) patients with low bacterial load (p<0.001). Co-infection with viruses was found significantly more frequent among patients with low bacterial load (24.2%) than those with high bacterial load (8.5%) [p<0.001]. Bacterial co-infection was also more frequently detected among patients with low bacterial load (22.4%) than in those with high bacterial load (12.1%) [p=0.01]. CONCLUSION: M. pneumoniae at a high bacterial load could be an etiologic agent of respiratory tract disease, whereas the etiologic role of MP at a low bacterial load remains to be determined. .

Hepatitis colestásica por Mycoplasma pneumoniae sin compromiso pulmonar: caso clínico y revisión de la literatura / Cholestatic hepatitis due to mycoplasma pneumoniae without lung involvement: case report and review

El compromiso hepático es una rara manifestación de la infección por Mycoplasma pneumoniae. Casos de hepatitis colestásica sin compromiso pulmonar han sido descritos en niños con infección por M. pneumoniae, pero en adultos sólo unos pocos casos han sido reportados. En este artículo, presentamos el caso de un hombre de 21 años que consultó por un cuadro de fiebre, ictericia y dolor epigástrico asociado con alteración de los exámenes de laboratorio hepático. Los estudios serológicos de M. penumoniae fueron positivos para IgM e IgG. Los síntomas y exámenes de laboratorio mejoraron completamente luego del tratamiento con claritromicina y ácido ursodeoxicólico.

Liver dysfunction is an unusual manifestation of Mycoplasma pneumoniae infection. Cases of cholestatic hepatitis without pulmonary involvement have been described in children with M. pneumoniae infection,but only a few cases have been reported in adults. In this article, we report the case of a 21-year-old man who presented fever, jaundice and epigastric pain associated with altered liver function tests. Serological tests for M. pneumoniae were positive for IgG and IgM. Clinical symptoms and laboratory tests resolved completely after treatment with clarithromycin and ursodeoxicolic acid. A review of reported cases of liver involvement in M. pneumoniae infection is presented.

Características clínicas de la enfermedad respiratoria causada por Mycoplasma pneumoniae en niños hospitalizados / Clinical characterizes of respiratory infection due to Mycoplasma pneumoniae in hospitalized children

Introduction: Studies onMycoplasmapneumoniae infection are scarce in Chile. Objective: To describe clinical characteristics associated withM. pneumoniae in children requiring hospitalization. Material and Methods: All children with a respiratory infection requiring hospitalizations between 2000-2005, whom had aM. pneumoniae specific IgM ≥ 1:32, were analyzed. Results: Fifty children meeting study criteria were identified with an ave-rage length of hospitalization of 4 days (range: 1-10); mean age was 5.4 years (46 percent were younger than 5 years). Common clinical features were cough (92 percent), fever (82 percent), malaise (74 percent) and respiratory distress (72 percent). At admission 40/45 children had hypoxemia. Chest-X ray showed interstitial pattern (69.3 percent), consolidation (51 percent) and hyperinsuflation (28.5 percent). Six patients had pleural effusion. Eighty four percent of patients had a favorable clinical outcome; eight children required admission to the PICU all of whom recovered. Conclusión: Respiratory infections associated withM. pneumoniae in our series of children had a highly variable and non-specific clinical spectrum. Chest-X rays showed different pattern in concordance with previous publications.

Introducción: La infección por Mycoplasma pneumoniae es una condición respiratoria poco estudiada en nuestro medio. Objetivo: Describir las características clínicas de los niños hospitalizados porM. pneumoniae. Materiales y Métodos: Se analizaron todos los pacientes hospitalizados por infecciones respiratorias durante el 2000-2005, con IgM específica; se utilizó como diagnóstico de enfermedad por M. pneumoniae la presencia de fluorescencia verde manzana 2 a 3 positivo en títulos ≥ 1:32 diluciones. Resultados: Se analizaron 50 hospitalizaciones, con estadía promedio de 4 días (rango: 1-10); la edad promedio fue 5,4 años (46 por ciento bajo 5 años). Los síntomas más frecuentes fueron tos (92 por ciento), fiebre (82 por ciento), compromiso del estado general (74 por ciento) y dificultad respiratoria (72 por ciento). Al momento del ingreso 40/45 presentaron hipoxemia. La radiografía de tórax (RT) reveló infiltrado intersticial (69,3 por ciento), foco de consolidación (51 por ciento) e hi-perinsuflación (28,5 por ciento). Seis presentaron efusión pleural asociada. En 84 por ciento la evolución fue favorable; sin embargo, 8 niños ingresaron a la Unidad de Paciente Critico para monitorización. No hubo decesos Conclusiones: La infección respiratoria asociada aM. pneumoniae en niños produjo manifestaciones inespecíficas y variables de un caso a otro. La RT reveló una variedad de presentaciones similar a lo mostrado en la literatura médica.

Prevalência de Chlamydia Pneumoniae e Mycoplasma Pneumoniae em diferentes formas da doença coronariana / Prevalencia de Chlamydia Pneumoniae y Mycoplasma Pneumoniae en diferentes formas de la enfermedad coronaria / Prevalence of Chlamydia Pneumoniae and Mycoplasma Pneumoniae in different forms of coronary disease

FUNDAMENTO: Vários agentes infecciosos foram investigados desde que se demonstrou a associação entre infecção e aterosclerose, porém os resultados desses estudos são conflitantes. OBJETIVO: Testar a associação entre títulos séricos de anticorpos anti-Chlamydia e anti-Mycoplasma em diferentes formas de síndromes coronarianas agudas (SCA). MÉTODOS: Cento e vinte e seis pacientes foram divididos em quatro grupos: SCA com elevação do segmento ST (32 pacientes), SCA sem elevação do segmento ST (30 pacientes), doença arterial coronariana crônica (30 pacientes) e doadores de sangue sem doença coronariana conhecida (34 pacientes - grupo-controle). Nos primeiros dois grupos, amostras de soro foram coletadas na admissão (primeiras 24 horas de hospitalização) e após 6 meses de seguimento. Nos outros dois grupos, colheu-se apenas uma amostra basal. Em todas as amostras, anticorpos IgG anti-Chlamydia e anti-Mycoplasma foram dosados por imunofluorescência indireta. RESULTADOS: Diferenças significativas foram observadas entre a medida basal e após 6 meses de seguimento nos pacientes com infarto do miocárdio com elevação do segmento ST, tanto para Chlamydia (650±115,7 vs. 307±47,5, p = 0,0001) quanto para Mycoplasma (36,5±5,0 vs. 21,5±3,5, p = 0,0004). Os grupos com SCA tiveram níveis séricos de anticorpos anti-Chlamydia e anti-Mycoplasma mais altos na dosagem basal, em relação aos pacientes com doença arterial coronariana crônica e grupo-controle, mas as diferenças obtidas não tiveram significância estatística. CONCLUSÃO: O presente estudo mostrou associação entre os títulos de anticorpos anti-Chlamydia e anti-Mycoplasma na fase aguda dos pacientes com angina instável ou infarto do miocárdio.

BACKGROUND: Several infectious agents have been investigated since the association between atherosclerosis and infection was demonstrated; however, the results of these studies are contradictory. OBJECTIVE: To test the association between serum titers of anti-Chlamydia and anti-Mycoplasma antibodies in different forms of acute coronary syndromes (ACS). METHODS: One hundred and twenty-six patients were divided in 4 groups: ACS with ST- segment elevation (32 patients), ACS without ST-segment elevation (30 patients), chronic coronary artery disease (30 patients) and blood donors without known coronary disease (34 patients - control group). In the two first groups, serum samples were collected at hospital admission (first 24 hours of hospitalization) and after a 6-month follow-up. In the other two groups, only a basal sample was collected. Anti-Chlamydia and anti-Mycoplasma antibodies were measured by indirect immunofluorescence in all samples. RESULTS: Significant differences were observed between the basal sample and the one measured after a 6-month follow-up in patients with myocardial infarction with ST-segment elevation for Chlamydia (650±115.7 versus 307±47.5, p=0.0001) as well as Mycoplasma (36.5±5.0 versus 21.5±3.5, p=0.0004). The groups with ACS had higher anti-Chlamydia and anti-Mycoplasma serum antibody levels in the basal measurement, when compared to the patients with chronic coronary disease and the control group, but the differences were not statistically significant. CONCLUSION: The present study showed an association between the serum titers of anti-Chlamydia and anti-Mycoplasma antibodies in the acute phase of patients with unstable angina or myocardial infarction.

FUNDAMENTO: Se han investigado diversos agentes infecciosos desde que se evidenció la asociación entre infección y aterosclerosis, sin embargo esos estudios ofrecen resultados conflictivos. OBJETIVO: Probar la asociación entre títulos séricos de anticuerpos anti-Chlamydia y anti-Mycoplasma en diferentes formas de síndromes coronarios agudos (SCA). MÉTODOS: Se dividieron a 126 pacientes en 4 grupos: SCA con elevación del segmento ST (32 pacientes), SCA sin elevación del segmento ST (30 pacientes), enfermedad arterial coronaria crónica (30 pacientes) y donadores de sangre sin enfermedad coronaria conocida (34 pacientes - grupo-control). En los primeros dos grupos, muestras de suero se colectaron al ingreso (primeras 24 horas de hospitalización) y tras 6 meses de seguimiento. En los otros dos grupos, se colectó solamente una muestra basal. En todas las muestras, se dosificaron anticuerpos IgG anti-Chlamydia y anti-Mycoplasma por inmunofluorescencia indirecta. RESULTADOS: Se observaron diferencias significativas entre la medida basal y tras 6 meses de seguimiento en los pacientes con infarto de miocardio con elevación del segmento ST, tanto para Chlamydia (650±115,7 vs 307±47,5, p = 0,0001) como para Mycoplasma (36,5±5,0 vs 21,5±3,5, p = 0,0004). Los grupos con SCA tuvieron niveles séricos de anticuerpos anti-Chlamydia y anti-Mycoplasma más altos en la dosificación basal, con relación a los pacientes con enfermedad arterial coronaria crónica y grupo-control, sin embargo las diferencias obtenidas no tuvieron significancia estadística. CONCLUSIÓN: El presente estudio reveló asociación entre los títulos de anticuerpos anti-Chlamydia y anti-Mycoplasma en la fase aguda de los pacientes con angina inestable o infarto de miocardio.

Association of common chronic infections with coronary artery disease in patients without any conventional risk factors.

BACKGROUND & OBJECTIVES: Report from the west suggest an association of infections and inflammation with atherosclerotic coronary artery disease (CAD). Entire microbial burden from several simultaneous chronic infections could be more important than a single infection in promoting atherosclerosis. No study has been done in Indian population, investigating the association of various chronic infections with CAD. We therefore evaluated the presence of markers of chronic infections in CAD patients having no conventional risk factors and healthy individuals in a tertiary care hospital in north India. METHODS: Seropositivity to IgG antibodies was investigated for Chlamydia pneumoniae, Mycoplasma pneumoniae, and Helicobacter pylori in 30 CAD patients with no conventional risk factors scheduled for coronary artery bypass surgery and in healthy blood donors. Periodontal pathogens were isolated by aerobic and anaerobic culture. RESULTS: All patients except one were < 55 yr of age and six were younger than 40 yr. Seropositivity to C. pneumoniae was significantly higher in CAD patients than healthy controls (63.3 vs. 23.3%, P<0.01). Combined seropositivity to both C. pneumoniae and M. pneumoniae was significantly higher in CAD patients with myocardial infarction (MI) than those without MI (61.5 vs. 11.8%, P<0.05). Aerobic and anaerobic cultures for the isolation of periodontal pathogens were positive in seven patients and five healthy blood donors. INTERPRETATION & CONCLUSION: C. pneumoniae seropositivity was significantly higher (P<0.001) in CAD patients without any of the conventional risk factors for CAD. Combined seropositivity to C. pneumoniae and M. pneumoniae was significantly higher (P<0.05) in CAD patients with MI than in those without MI. Possibly CAD in young is not (or less) governed by conventional risk factors, and infectious agents can be potential risk factors for the development of atherosclerosis and CAD in this subset of patients.

Utilidad de la reacción de polimerasa en cadena para la detección de Mycoplasma pneumoniae en adultos mayores con neumonía adquirida en la comunidad / Diagnostic utility of the polymerase chain reaction for the diagnosis of Mycoplasma pneumoniae in elderly patients with community-acquired pneumonia

Mycoplasma pneumoniae es una causa frecuente de neumonía adquirida en la comunidad (NAC) en niños y adultos jóvenes, existiendo escasa información de su frecuencia en el adulto mayor. Se analizó la reacción de polimerasa en cadena (RPC) con dos pares de partidores, gen de la adhesina P1 y gen 16S rRNA, para la detección de M. pneumoniae en lavado faríngeo de 84 pacientes de 60-96 años con diagnóstico clínico de NAC, desde septiembre de 2002 hasta agosto de 2004. Los resultados de la RPC fueron comparados con los de la serología mediante inmunofluorescencia indirecta (IFI). Se detectó infección por M. pneumoniae mediante serología o RPC en 11 de 84 pacientes (13,1%). La serología fue positiva en 8 (72,7%) y la RPC en 7 (63,6%) muestras. La serología en la muestra de suero en fase aguda fue positiva en 5 de 11 pacientes (45,4%), en 4 de ellos por la presencia de IgM. En 4 pacientes con serología positiva la RPC fue negativa. En 3 pacientes con serología negativa la RPC fue positiva. Las dos RPC mostraron 100% de correlación y la sensibilidad fue la misma; no se detectaron muestras con efecto inhibitorio de la reacción. En conclusión, M. pneumoniae debería ser considerado en la etiología de la NAC en adultos mayores. La detección de este microorganismo debe basarse en el uso combinado de serología y RPC.

Chlamydia pneumoniae e Mycoplasma pneumoniae nos nódulos de calcificacão da estenose da valva aórtica / Chlamydia pneumoniae and Mycoplasma pneumoniae in calcified nodes of stenosed aortic valves

OBJETIVO: Investigar se chlamydia pneumoniae (CP) ou mycoplasma pneumoniae (MP) estão presentes na estenose da valva aórtica (EA). MÉTODOS: Imuno-histoquímica foi utilizada para identificar os antígenos de CP (Ag-CP), a hibridizacão in situ para identificar o DNA de MP, e microscopia eletrônica para avaliacão dos dois agentes, nos grupos: normal - 11 valvas normais de autópsia; aterosclerose - 10 valvas de pacientes com aterosclerose sistêmica de autópsia e sem EA; e EA - 14 espécimes cirúrgicos provenientes de pacientes com EA analisados em 3 sub-regiões: EA-preservada - regiões mais preservadas na periferia da valva; EA-fibrose - tecido fibrótico peri-calcificacão; e EA-calcificacão - nódulos calcificados. RESULTADOS: As medianas da fracão de área positiva para Ag-CP foram 0,09; 0,30; 0,18; 1,33; e 3,3 nos grupos acima descritos, respectivamente. A densidade de CP foi significativamente maior nos grupos aterosclerose e EA-calcificacão em relacão ao normal (p<0,05). Dentro do grupo EA, a quantidade de CP foi maior nas regiões de fibrose e calcificacão (p<0,05). As fracões de área positivas para MP-DNA (medianas) foram 0,12; 0,44; 0,07; 0,36; e 1,52 nos grupos acima descritos, respectivamente. A quantidade de MP-DNA foi maior na EA-calcificacão em relacão ao normal (p<0,05). Dentro do grupo EA, maior quantidade de MP-DNA foi encontrada nas regiões de calcificacão e fibrose (p<0,05). CONCLUSAO: Os nódulos de calcificacão da EA tinham maior concentracão de CP e MP sugerindo que essas bactérias possam estar associadas ao desenvolvimento de calcificacão e inflamacão, apontando novas semelhancas entre os processos de EA e aterosclerose, que podem ter mecanismos infecciosos envolvidos.

Etiologies and treatment outcomes in patients hospitalized with community-acquired pneumonia (CAP) at Srinagarind Hospital, Khon Kaen, Thailand.

Local epidemiological data on the etiologies of in-patients who are hospitalized with CAP is needed to develop guidelines for clinical practice. This study was conducted to determine the pattern of microorganisms causing community-acquired pneumonia (CAP) in adult patients admitted to Srinagarind Hospital, Khon Kaen, Thailand, between January 2001 and December 2002. Altogether, 254 patients (124 males, 130 females) averaging 56.4 (SD 19.8) years were included. Eighty-six of them (33.8%) presented with severe CAP on initial clinical presentation. The etiologies for the CAP cases were discovered by isolating the organisms from the blood, sputum, pleural fluid, and other sterile sites. Serology for Chlamydia pneunmoniae and Mycoplasma pneumoniae were performed to diagnose current infection. The causative organisms were identified in 145 patients (57.1%). Streptococcus pneumoniae was the commonest pathogen, identified in 11.4% of the cases, followed by Burkholderia pseudomallei (11.0%) and Klebsiella pneumoniae (10.2%). The atypical pathogens, C. pneumoniae and M. pneumoniae, accounted for 8.7% and 3.9% of the isolates, respectively. Sixteen patients (6.3%) had dual infections; C. pneumoniae was the most frequent coinfecting pathogen. The average length of hospital stay was 12.9 (SD 14.0) days, with 27.9% staying more than 2 weeks. Overall, 83.9% of the patients improved with treatment, 10.2% did not improve and 5.9% died. The most common complications were acute respiratory failure (31.1%) and septic shock (20.9%). We conclude that initial antibiotic use should cover the atypical pathogens, C. pneumoniae and M. pneumoniae, in hospitalized CAP patients. B. pseudomallei is an endemic pathogen in Northeast Thailand, and should be considered in cases of severe CAP.

Distributions of Antibody Titers to Mycoplasma pneumoniae in Korean Children in 2000-2003

The aim of study was to describe Mycoplasma pneumoniae epidemics in a hospital-based population. Special attention was paid to the relationship between antibody titer to M. pneumoniae and sex, age, and atopy. During the eight 6-month periods between January 2000 and December 2003, serum samples were obtained from 1,319 Korean children who presented with respiratory symptoms, and were examined for antibodies to M. pneumoniae using the indirect particle agglutination test. Geometric mean antibody titers peaked in the second half of 2000 and then decreased gradually, a second peak occurred in the second half of 2003. Likewise, the frequency of high antibody titers (>or=1:640) also peaked during these two periods. Antibody titers in children aged 0-3 yr were lower than in older children during both peak periods and for 2 yr after the first peak. Sex and atopy had no effect on antibody titers. During the years 2000-2003, geometric mean antibody titers and the frequencies of high antibody titers varied with time. These changes suggest a cyclic pattern of M. pneumoniae infection, with two epidemic peaks separated by 3 yr.

Serological study of Mycoplasma pneumoniae infections.

Mycoplasma pneumoniae antibody was determined in 811 sera of different patients admitted to Siriraj Hospital with respiratory tract infection from July 1, 2000 to August 31, 2003 by agglutination with gelatin particle agglutination test kit (SERODIA-MYCO II, Fujirebio Inc. Japan) in microtiter plates. Three hundred and three sera were positive (37.36%). The five most positive titer were found in patients 5-9 yr (40.26%), followed by patients 1-4 yr (24.75%), 10-14 yr (19.80%), 30-39 yr (5.28%) and 20-29 yr (3.96%). The positive titers ranged from 40 to > 20,480. Female:male ratio in positive patients was approximately the same (1.19:1). High titers (> or = 320) were found in 146 out of 303 patients (48.18%). The infection was mostly found in children aged 5-9 yr. Detection of antibody to M. pneumoniae infection showed that 37.36% of patients who were suspected of having atypical bacterial pneumonia were positive.

Prevalence of Mycoplasma pneumoniae and Chlamydia pneumoniae in children with community acquired pneumonia.

A prospective one year study was performed on 62 children admitted at the All India Institute of Medical Sciences with community acquired pneumonia (CAP) for the prevalence of Mycoplasma pneumoniae and Chlamydia pneumoniae. Diagnosis of infection with M. pneumoniae was based on serological tests viz microparticle agglutination test for detection of IgM antibodies and indirect immunofluorescence test for antigen detection from throat swabs (sensitivity 85.7%, specificity 93.3%). The indirect solid-phase enzyme immunoassay for detection of IgG antibodies was used to determine the prevalence of C. pneumoniae (sensitivity 88.8%, specificity 75.8%). Seventeen patients (27.4%) were found to have serological evidence of M. pneumoniae infection whereas only 4 (6.4%) patients were seropositive for C. pneumoniae. Results of this study indicate that M. Pneumoniae plays a significant role in CAP in infants and young children. Thus specialized laboratory testing for these agents should be more widely used thereby affecting empiric antibiotic regimens.

Anticuerpos anti-mycoplasma pneumoniae en pediatría / Anti-mycoplasma pneumoniae antibodies in pediatrics

Investigamos la prevalencia de anticuerpos anti-mycoplasma pneumoniae y su relación con la edad en 235 niños sanos de la ciudad de Buenos Aires. Se identificaron anticuerpos anti-mycoplasma pneumoniae a través de ELISA en 22,1 por ciento. La proporción de seropositivos no varió significativamente con la edad. Nuestro estudio sugiere que la identificación por mycoplasma pneumoniae puede ser tan frecuente en preescolares como en escolares y adolescentes

Inflammatory pseudotumor of the lung in a child with mycoplasma pneumonia

A case of inflammatory pseudotumor of the lung occurring in a six-year-old boy is reported with clinicopathologic findings, including its ultrastructure. The patient had had frequent upper respiratory tract infections, and one and half year before the discovery of the lung mass, he suffered from pneumonia of the right lung, which was serologically proven to be a mycoplasma pneumoniae infection. Exploratory thoracotomy revealed a large mediastinal mass that was removed together with the right middle and lower lobes of the lung. The mass arose from the lung with an endobronchial element. Microscopically, the mass was composed of a variety of inflammatory and mesenchymal cells, including plasma cells, histiocytes, lymphocytes, and fibroblast-like spindle cells. Ultrastructurally, the spindle-shaped mesenchymal cells were either fibroblasts or myofibroblasts. At the time of diagnosis of the inflammatory pseudotumor of the lung, the serum titer of antimycoplasma antibody rose again, and the lung parenchyma adjacent to the mass showed interstitial pneumonia with features of bronchiolitis obliterans. The present case suggests that the inflammatory pseudotumor of the lung could be a postinflammatory lesion associated with mycoplasma pneumoniae infection.

Incidencia de Mycoplasma pneumoniae en Venezuela / Incidence of Mycoplasma pneumoniae in Venezuela

Entre enero de 1974 y enero de 1984 se realizó un estudio con el fin de conocer la incidencia de Mycoplasma pneumoniae en Venezuela, evaluándose un total de 1.700 muestras. De ellas, 1.350 correspondieron a sueros de sujetos asintomáticos desde el punto de vista respiratorio, 700 femeninos y 650 masculinos, edivididos en 7 grupos etarios, desde 6 meses hasta 65 años, en los cuales se determinaron los niveles de anticuerpos contra el agente mencionado por técnica de inhibición metabólica: reducción del rojo de tetrazolium (im). Igualmente se investigaron 350 pacientes adultos, de edades comprendidas entre 15 y 40 años, con diferentes cuadros respiratorios, dividiéndose en grupos: Nª1: con resfrio común, Nª 2: con faringitis, bronquitis y/o "influenza", y Nª3: con neumonía. Todos estos pacientes fueron negativos desde el punto de vista virológico. En ellos se realizó tanto diagnóstico serológico, mediante técnicas de IM, fijación de complemento (FC) y hemaglutinación pasiva (HAP), como aislamiento e identificación del agente etiológico mediante procedimientos recomendados por el Center for Diseases Control de atlanta (CDC). Los resultados de la encuesta serologica arrojaron una positividad del 28% para presencia de anticuerpos contra M. pneumoniae, sobre el total de la población evaluada, siendo la mayor incidencia en el grupo de 21 a 30 años con un 46%. En el grupo de pacientes con patología respiratoria la positividad fue la siguiente: 0% para resfrío común, 6% para faringitis-bronquitis influenza y 20% para neumonía. De los 26 casos diagnosticados, 17 lo fueron por serología, 1 por aislamiento y 8 por ambos métodos. Los hallazgos obtenidos nosdemuestran que la incidencia de M. pneumoniae en nuestro medio es muy similar a la de otros países, aún con diferentes condiciones climáticas, socioeconómicas y sanitarias