OBJECTIVETo investigate the percentage of T lymphocyte subsets and allergen screening results in infants and young children with Mycoplasma pneumoniae (MP) infection complicated by wheezing.

METHODSFlow cytometry was used to measure the percentage of peripheral blood T cell subsets in 354 infants and young children with MP infection complicated by wheezing (MP wheezing group), 336 infants and young children with MP infection but without wheezing (MP non-wheezing group), and 277 children with recurrent wheezing (recurrent wheezing group). Allergen screening was also performed for these children.

RESULTSBoth the MP wheezing group and recurrent wheezing group had significantly lower percentages of CD3and CD3CD8lymphocytes than the MP non-wheezing group (p<0.05). The MP groups with or without wheezing had a significantly higher percentage of CD3CD4lymphocytes than the recurrent wheezing group (p<0.05). Both the MP wheezing group and recurrent wheezing group had significantly higher percentages of CD3CD19and CD19CD23lymphocytes than the MP non-wheezing group (p<0.05), and the recurrent wheezing group had the highest percentages (p<0.05). The overall positive rate of food allergens was significantly higher than that of inhaled allergens (30.3% vs 14.7%; p<0.05). The positive rates of food and inhaled allergens in the recurrent wheezing group and MP wheezing group were significantly higher than in the MP non-wheezing group (p<0.05), and the recurrent wheezing group had the highest rates.

CONCLUSIONSImbalance of T lymphocyte subsets and allergic constitution play important roles in the pathogenesis of MP infection complicated by wheezing in infants and young children.

Allergens ; immunology ; Child, Preschool ; Female ; Humans ; Infant ; Male ; Pneumonia, Mycoplasma ; complications ; immunology ; Respiratory Sounds ; etiology ; T-Lymphocyte Subsets ; immunology

Acquired hemophilia is a rare disorder caused by autoantibodies to factor VIII (FVIII) (also referred to as factor VIII inhibitors or anti-FVIII) and may be associated with pregnancy, underlying malignancy, or autoimmune disorders. A 33-month-old girl who presented with hematochezia and ecchymotic skin lesions was diagnosed with Mycoplasma pneumoniae pneumonia by serology and polymerase chain reaction. Hematologic studies showed a prolonged activated partial thromboplastin time (aPTT), partially corrected mixing test for aPTT, reduced levels of FVIII, and the presence of antibodies against FVIII. She was treated conservatively with prednisone and intravenous immunoglobulin (IVIG) without FVIII transfusion and recovered without sequelae. This report provides the first description of acquired hemophilia due to anti-FVIII in association with M. pneumoniae in Korea. We discuss this case in the context of the current literature on acquired hemophilia in children.
Autoantibodies/blood ; Child, Preschool ; Factor VIII/immunology ; Female ; Hemophilia A/*etiology ; Humans ; Partial Thromboplastin Time ; Pneumonia, Mycoplasma/*complications/immunology ; Time Factors

OBJECTIVETo investigate the effect of Mycoplasma pneumoniae (MP) infection on the function of T lymphocytes in the bronchoalveolar lavage fluid (BALF) of asthmatic children in acute and stable periods and the relationship between MP infection and asthma.

METHODSSeventy-one hospitalized children (with bronchitis, pneumonia, and asthma) were divided into non-MP infection control group (group A, pneumonia and bronchitis without MP infection), non-MP infection asthma group (group B), and MP infection asthma group (group C). Flow cytometry was used to determine CD3(+), CD4(+), and CD8(+) T cell counts and CD4(+)/CD8(+) ratio in BALF among all children in acute and stable periods.

RESULTSCompared with group A, groups B and C showed significant differences in CD3(+), CD4(+), and CD8(+) T cell counts and CD4(+)/CD8(+) ratio (P<0.05) in acute and stable periods, had decreased CD3(+) and CD4(+) T cell counts, an increased CD8(+) T cell count, and a significantly decreased CD4(+)/CD8(+) ratio (P<0.05) in the acute period, and had decreased CD3(+) and CD4(+) T cell counts and CD4(+)/CD8(+) ratio and an increased CD8(+) T cell count (P<0.05) in the stable period. Compared with group B, group C had significantly decreased CD3(+) and CD4(+) T cell counts and CD4(+)/CD8(+) ratio (P<0.05) and a significantly increased CD8(+) T cell count (P<0.05) in the acute period and showed no significant differences in CD3(+), CD4(+), and CD8(+) T cell counts (P>0.05) and a significant decrease in CD4(+)/CD8(+) ratio (P<0.05) in the stable period.

CONCLUSIONSThe immunological function of T lymphocytes in the airway declines significantly among asthmatic children with MP infection in acute and stable periods, leading to immue system disorder. MP may be associated with the pathogenesis of asthma.

Asthma ; etiology ; immunology ; Bronchoalveolar Lavage Fluid ; immunology ; CD4-CD8 Ratio ; Child ; Child, Preschool ; Female ; Humans ; Male ; Pneumonia, Mycoplasma ; complications ; immunology ; T-Lymphocytes ; immunology

BACKGROUNDMycoplasma pneumoniae (M. pneumoniae) is a frequent cause of respiratory tract infections. However, there is deficient knowledge about the clinical manifestations of M. pneumoniae infection. We described the clinical and laboratory findings of M. pneumoniae pneumonia in hospitalized children who were all diagnosed by a ≥ fourfold increase in antibody titer.

METHODSM. pneumoniae antibodies were routinely detected in children admitted with acute respiratory infection during a one-year period. The medical history was re-collected from children whose M. pneumoniae antibody titer increased ≥ fourfold at the bedside by a single person, and their frozen paired serum samples were measured again for the M. pneumoniae antibody titer.

RESULTSOf the 635 children whose sera were detected for the M. pneumoniae antibody, paired sera were obtained from 82 and 29.3% (24/82) showed a ≥ fourfold increase in antibody titer. There were 24 cases, nine boys and 15 girls, aged from two to 14 years, whose second serum samples were taken on day 9 at the earliest after symptom onset; the shortest interval was three days. All children presented with a high fever (≥ 38.5°C) and coughing. Twenty-one had no nasal obstruction or a runny nose, and five had mild headaches which all were associated with the high fever. The disease was comparatively severe if the peak temperature was > 39.5°C. All were diagnosed as having pneumonia through chest X-rays. Four had bilateral or multilobar involvement and their peak temperatures were all ≤ 39.5°C. None of the children had difficulty in breathing and all showed no signs of wheezing.

CONCLUSIONSThe second serum sample could be taken on day 9 at the earliest after symptom onset meant that paired sera could be used for the clinical diagnosis of M. pneumoniae pneumonia in children at the acute stage. M. pneumoniae is a lower respiratory tract pathogen. Extrapulmonary complications were rare and minor in our study. High peak temperature (> 39.5°C) is correlated with the severity of M. pneumoniae pneumonia in children.

Acute Disease ; Adolescent ; Antibodies, Bacterial ; blood ; Child ; Child, Hospitalized ; Child, Preschool ; Female ; Humans ; Male ; Mycoplasma pneumoniae ; immunology ; Pneumonia, Mycoplasma ; complications ; diagnosis ; drug therapy ; Radiography, Thoracic

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.
Antibodies, Bacterial/blood ; Bronchiolitis Obliterans/complications ; Child ; Diagnosis, Differential ; Fibroma/etiology/*pathology/surgery ; Humans ; Lung Neoplasms/etiology/*pathology/surgery ; Male ; Mycoplasma pneumoniae/immunology/*pathogenicity ; Pneumonia, Mycoplasma/complications/microbiology/*pathology ; Tomography, X-Ray Computed

This study investigated the serum vascular endothelial growth factor (VEGF) levels in children with community-acquired pneumonia. Serum VEGF levels were measured in patients with pneumonia (n=29) and in control subjects (n=27) by a sandwich enzyme-linked immunosorbent assay. The pneumonia group was classified into bronchopneumonia with pleural effusion (n=1), bronchopneumonia without pleural effusion (n=15), lobar pneumonia with pleural effusion (n=4), and lobar pneumonia without pleural effusion (n=9) groups based on the findings of chest radiographs. We also measured serum IL-6 levels and the other acute inflammatory parameters. Serum levels of VEGF in children with pneumonia were significantly higher than those in control subjects (p<0.01). Children with lobar pneumonia with or without effusion showed significantly higher levels of serum VEGF than children with bronchopneumonia. For lobar pneumonia, children with pleural effusion showed higher levels of VEGF than those without pleural effusion. Children with a positive urinary S. pneumonia antigen test also showed higher levels of VEGF than those with a negative result. Serum IL-6 levels did not show significant differences between children with pneumonia and control subjects. Serum levels of VEGF showed a positive correlation with the erythrocyte sedimentation rate in the children with pneumonia. In conclusion, VEGF may be one of the key mediators that lead to lobar pneumonia and parapneumonic effusion.
Vascular Endothelial Growth Factor A/*blood ; Streptococcus pneumoniae/growth & development/immunology ; Pneumonia, Bacterial/*blood/complications/microbiology ; Pleural Effusion/*blood/complications/microbiology ; Mycoplasma pneumoniae/growth & development/immunology ; Male ; Interleukin-6/blood ; Infant ; Humans ; Female ; Enzyme-Linked Immunosorbent Assay ; Community-Acquired Infections/blood/microbiology ; Child, Preschool ; Child ; Antigens, Bacterial/immunology ; Antibodies, Bacterial/immunology ; Adolescent

Reported herein is an adult case of Fisher syndrome (FS) that occurred as a complication during the course of community-acquired pneumonia caused by Mycoplasma pneumoniae. A 38-yr-old man who had been treated with antibiotics for serologically proven M. pneumoniae pneumonia presented with a sudden onset of diplopia, ataxic gait, and areflexia. A thorough evaluation including brain imaging, cerebrospinal fluid examination, a nerve conduction study, and detection of serum anti-ganglioside GQ1b antibody titers led to the diagnosis of FS. Antibiotic treatment of the underlying M. pneumoniae pneumonia was maintained without additional immunomodulatory agents. A complete and spontaneous resolution of neurologic abnormalities was observed within 1 month, accompanied by resolution of lung lesions.
Adult ; Anti-Bacterial Agents/therapeutic use ; Antibodies/blood ; Diplopia/etiology ; Erythrocyte Count ; Gangliosides/immunology ; Humans ; Lung/radiography ; Male ; Miller Fisher Syndrome/*diagnosis/etiology ; Pneumonia, Mycoplasma/complications/*diagnosis/drug therapy ; Tomography, X-Ray Computed