A fulminant case of acute respiratory distress syndrome associated with Mycoplasma pneumoniae infection.

Acute respiratory distress syndrome (ARDS) caused by mycoplasmas is very rare. This report describes a severe case of atypical pneumonia due to M. pneumoniae in a formerly healthy young woman who developed high grade fever and cough leading to severe disseminated lung disease and finally to fatal ARDS. This case came into picture when killer atypical pneumonia, namely, SARS (severe acute respiratory syndrome), spread very fast from South-Asian countries to the rest of the world. Moreover, the clinical presentation and radiologic features of SARS bear resemblance to the syndrome of atypical pneumonia, which lead us to investigate this case into detail. We suggest that M. pneumoniae infections should be included in the differential diagnosis of pathogens causing ARDS, establishing an early diagnosis may have important therapeutic implications.

Prevalence of Mycoplasma pneumoniae Antibodies in Healthy Residents of Jeonnam Province / 대한임상미생물학회지

BACKGROUND: Mycoplasma pneumoniae is the most frequent cause of respiratory tract infections in schoolaged children and adolescents. For appropriate use of antibiotics, diagnosis of M. pneumoniae infection in routine clinical practice has been based on serology using a single serum sample. We evaluated the seroprevalence of anti-M. pneumoniae-specific antibodies in 500 asymptomatic, healthy persons in Jeonnam Province. METHODS: Sera were collected from 500 healthy persons in Jeonnam Province. Anti-M. pneumoniae antibody titer was measured using a microparticle agglutination assay Serodia Myco II (Fujirebio, Japan) and VIRCELL IgM Mycoplasma ELISA kits (Vircell, Granada, Spain). RESULTS: Anti-M. pneumoniae antibody titers in 500 healthy individuals were 1:20 in 344 (68.8%), 1:40 in 16 (3.2%), 1:80 in 71 (14.2%), 1:160 in 45 (9.0%), 1:320 in 14 (2.8%), and 1:160) and positive IgM, and an assessment of current infection with single serum serology has its limitation for the diagnosis of M. pneumoniae infections.

Comparison of Clinical Characteristics of Mycoplasma pneumoniae Pneumonia According to the Pleural Effusion / 소아알레르기및호흡기학회지

PURPOSE:Mycoplasma pneumoniae (M. pneumoniae) is a major cause of respiratory infections in school-aged children. Complications of M. pneumoniae pneumonia include atelectasis, pleural effusion, empyema, pneumothorax and bronchiectasis. We evaluated the clinical characteristics of M. pneumoniae pneumonia with pleural effusion. METHODS:A total of 210 medical records of children who were admitted to the Dong-A University hospital due to M. pneumoniae pneumonia from 2000 to 2004 were retrospectively analyzed. Diagnosis of M. pneumoniae pneumonia was based on the single titer of antimycoplasmal antibody higher than 1:320. Enrolled children were divided into Group A (with pleural effusion) and Group B (without effusion). We analysed the differences between the two groups according to sex, age, onset, symptoms, clinical manifestations, laboratory findings and chest x-rays. RESULTS:There were no significant differences in age, sex and clinical manifestations between the two groups. Group A had longer fever durations (9.3+/-7.8 days vs 5.0+/-3.7 days), and a longer duration of hospitalization (10.4+/-6.3 days vs 6.9+/-6.3 days) compare to Group B. Also, compared to the Group B, Group A had higher ESR (49.6+/-32.9 mm/hr vs 28.7+/-20.4 mm/hr), CRP (23.0+/-60.4 mg/dL vs 8.7+/-30.9 mg/dL), SGOT (67+/-74.2 IU/L vs 53.6+/-60.0 IU/L), SGPT (37.4+/-18.6 IU/L vs 26.2+/-16.9 IU/L). There was no significance between antimycoplasmal antibody titer and pleural effusion. CONCLUSION:This study shows that M. pneumoniae pneumonia with pleural effusion has a longer duration of fever and hospitalization, higher ESR, CRP, SGOT, SGPT compare to the M. pneumoniae pneumonia without pleural effusion. We conclude that these findings could be used as the prognostic factors in M. pneumoniae pneumonia with pleural effusion.

Detección de Mycoplasma pneumoniae mediante PCR-hibridación in vitro en niños con infección respiratoria / Mycoplasma pneumoniae detection using PCR-in vitro hybridization in children with respiratory infection

Antecedentes: Las infecciones respiratorias agudas (IRA) son una de las causas más frecuentes de enfermedades en el mundo y pueden asociarse a complicaciones graves, entre las que la neumonía ocupa un lugar prioritario; diversos agentes virales y bacterianos se implican en su desarrollo. Recientemente Mycoplasma pneumoniae ha adquirido gran importancia ya que estudios epidemiológicos sugieren un aumento en la incidencia de enfermedades respiratorias causadas por este patógeno. Sin embargo, los laboratorios clínicos enfrentan varias dificultades para su detección haciendo necesario el estudio de nuevas técnicas moleculares. Objetivo: Detección de M. pneumoniae mediante PCR-hibridación in vitro en niños con infección respiratoria. Métodos: Utilizando la técnica de PCR-hibridación in vitro se analizaron 36 hisopados orofaríngeos de niños entre los 0 y 9 años de edad con infección respiratoria; 36% presentaron neumonía y el 30% bronconeumonía. Resultados: La implementacion y utilización de la técnica de PCR-hibridación in vitro para la detección de M. pneumoniae permitió detectar su ADN en el 67% de los pacientes estudiados. De éstos, el 33% tenía diagnóstico de neumonía. Conclusión: La técnica de PCR-hibridación in vitro demostró ser útil en la detección de M. pneumoniae en las muestras analizadas. Los resultados de este estudio evidencian que la presencia de ácidos nucleicos de este patógeno es frecuente en las muestras respiratorias analizadas y sugiere que el microorganismo puede ser un agente etiológico frecuente de neumonías atípicas y de otras patologías respiratorias.

Background: Acute respiratory infection is considered one of the main causes of morbidity worldwide; it can be associated to serious complications. A great number of viral and bacterial agents have been implicated in the development of the disease. Recently, importance has been given to Mycoplasma pneumoniae as a respiratory pathogen, since epidemiologic studies suggest a raise in the incidence of diseases due to this microorganism. Nevertheless, nowadays clinical laboratories deal with a variety of difficulties in the diagnosis of this agent, raising the need for other molecular methods for its detection. Objective: The detection of M. pneumoniae in children with respiratory infection by a PCR-in vitro hybridization technique. Methods: 36 oropharyngeal swabs from children between 0 and 9 years of age with respiratory infection were analyzed by PCR-in vitro hybridization; 36% had pneumonia and 30% bronchopneumonia. Results: The implementation of the PCR-in vitro hybridization for the detection of M. pneumoniae in patients with respiratory infection allowed the detection of the pathogen's DNA in 67% of the patients studied. Of these, 33% had pneumonia. Conclusion: PCR-in vitro hybridization is useful for the detection of M. pneumoniae. Our results show the frequent presence of nucleic acids of M. pneumoniae in the samples studied and suggest this microorganism can be a frequent causal agent of respiratory infection.

Influence of Mycoplasma Pneumoniae Infection on the Growth, Phagocytie Activities and Induction of Nitric Oxide Production of the Microglial Cells of Mice

In this study, the distribution and reisolation of Mycoplasma pneumoniae(Mp) were observed from the various tissues of BALB/c mice which were intraperitoneally pre-inoculated with Mp. In addition, the effect of Mp on the growth, phagocytic activities and nitric oxide production of microglial cells were also examined. The results were as follows; 1) Mp was reisolated from the various tissues such as lymph node, spleen, liver, kidney, brain and blood from one hour through 48 hours after intra-peritoneal inoculation of Mp in mice by the cultural method. Furthermore, it could also be confirmed from those tissues up to 72 hours by the indirect immunofluorescent antibody method. 2) There was no difference in the phagocytic activities between the control microglial cells and Mp stimulated microglial cells. 3) The growth of microglial cells in the medium was significantly increased by the stimulation with Mp compared with that of the control. 4) Nitric oxide production of mouse microglial cells was increased by the combined treatment if IFN-r and LPS or IFN-r and Mp or IFN-r, LPS and Mp, whereas, no increase was observed by either LPS or Mp alone. 5) Nitric oxide production of microglial cells primed with IFN-r was closely related with the dose of LPS and Mp in the dose dependent manner rather than that of the IFN-r. These results suggest that; i) Mp spreads to the various tissues of mice within one hour after intraperitoneal inoculation, ii) the growth of microglial cells increases by the infection of Mp, iii) microglial cells have phagocytic activities to C.albicans and iv) nitric oxide production of microglial cells was augmented by the infection of Mp. Increased nitric oxide production of microglial cells is regarded as an increase of the intracellular bactericidal activiteis of microglial cells. It is suggested, nonetheless, that the inflammatory response of the Mp infected tissues is augmented by the increase of nitric oxide.