Clinical Aspects of Necrotizing Pneumonitis Resulting from Mycoplasma pneumoniae Infection in Children

Lee, Na Young; Hur, Tae Hyung; Song, Sun Wha; Lee, Hae Kyung; Lee, Keun Young; Lee, Hyun Seung; Jang, Pil Sang; Kim, Dong Un; Kim, Young Hoon; Kim, Jin Tack

Abstract

PURPOSE: Necrotizing pneumonitis is a complication of severe invasive lobar pneumonia characterized by necrotic foci in consolidated areas and its development may be due to excessive host cell-mediated immune response. Necrotizing pneumonitis caused by Mycoplasma pneumoniae (M. pneumoniae) in children and its successful treatment have been reported. We reviewed 5 cases to determine the disease course and outcome in pediatric patients with necrotizing pneumonitis resulting from M. pneumoniae infection.
METHODS
Five patients with necrotizing pneumonitis caused by M. pneumoniae who were diagnosed and treated in the Department of Pediatrics, Uijeongbu St. Mary`s Hospital from January 2003 to December 2006 were reviewed in this study. Sex, age, clinical manifestations, laboratory and radiologic findings, treatments, and long-term follow-up outcomes of these patients were analysed retrospectively.
RESULTS
One patient was a boy and others were girls. All were less than 5 years of age and had no immunocompromised conditions. Lower pH and glucose, higher protein and LDH were observed in pleural fluid. On the radiologic examinations, all had multilobar pneumonic involvements, especially in the right lobes and lower lobes. Necrotizing pneumonitis was diagnosed on chest CTs taken between two and 20 days following admission. The necrotic foci were identified as multiple low-attenuation changes within the contrast-enhanced consolidation areas mainly in the lower lobes of the affected side of lung. Cavitary necrosis was shown in 3 patients and persisted as pneumatoceles, which disappeared on the follow-up chest radiographs nearly up to 7 months following admission. Macrolide and broad-spectrum antibiotics were administered in all patients and chest tube drainage was performed in 2 patients. Systemic steroid therapy was added in 4 patients. Of those four, 2 patients, both under 2 years of age, improved more rapidly than others in clinical status and radiographic findings. In spite of steroid therapy, one patient died of acute respiratory distress syndrome. Consequently 4 patients were improved and discharged. Two patients who were under 2 ears were normalized and 2 patients who were 4 years of age showed remaining cavitation or fibrosis in the last follow-up chest radiographs.
CONCLUSION
Our results may suggest though they are not yet proven nor have they been discussed extensively that younger patients show better prognoses than older children. Further well-designed and large scale studies may be warranted.