Case Report: Clinical Analysis of Fulminant Mycoplasma pneumoniae Pneumonia in Children

Summary Objectives To determine the efficacy of methylprednisolone pulse therapy for children with Mycoplasma pneumoniae pneumonia (MP) that is refractory to antibiotic treatment. Methods Refractory patients were defined as cases showing clinical and radiological deterioration despite appropriate antibiotic therapy for 7 days or more. We identified 6 such children (male/female: 3/3) aged 3–9 years who were treated between 1998 and 2006. During the same period, 190 children with MP were admitted to our institution. Results Common laboratory findings of the patients included cytopenia, elevated serum lactate dehydrogenase and ferritin levels, and elevated urine β2-microglobulin levels, suggesting complication of hypercytokinemic condition. We initiated intravenous methylprednisolone at a dose of 30 mg/kg on 10.2 ± 2.8 clinical days and administered it once daily for 3 consecutive days. Fever subsided 4–14 h after initiation of steroid pulse therapy in all patients. This dramatic effect was accompanied by rapid improvement of radiological abnormalities including infiltrates and pleural effusion, followed by improvement of laboratory abnormalities. There were no adverse events of steroid therapy. Conclusions This is the first case-series study showing an effect of 3-day methylprednisolone pulse therapy on refractory MP in children. This therapy is apparently an efficacious and well-tolerated treatment for refractory MP.

Mycoplasma pneumoniae is one of the most common causes of community-acquired pneumonia in children and young adults. The incidence of fulminant M. pneumoniae pneumonia (MPP) is relatively rare despite the high prevalence of M. pneumoniae infection. This literature review highlights the clinical features of fulminant MPP by examining the most recent data in epidemiology, clinical presentation, pathogenesis, and treatment. Fulminant MPP accounts for 0.5–2% of all MPP cases and primarily affects young adults with no underlying disease. Key clinical findings include a cough, fever, and dyspnea along with diffuse abnormal findings in radiological examinations. Levels of inflammatory markers such as white blood cells and C-reactive protein are elevated, as well as levels of lactate dehydrogenase, IL-18, aspartate transaminase, and alanine transaminase. The exact pathogenesis of fulminant MPP remains unclear, but theories include a delayed hypersensitivity reaction to M. pneumoniae and the contribution of delayed antibiotic administration to disease progression. Treatment options involve pairing the appropriate anti-mycoplasma agent with a corticosteroid that will downregulate the hypersensitivity response, and mortality rates are quite low in this treatment group. Further research is necessary to determine the exact pathogenesis of severe and fulminant types of MPP.

Purpose Mycoplasma pneumoniae (M. pneumoniae) is one of the most common causes of community-acquired pneumonia in children. The clinical course is typically self-limited and benign; however, rare cases of severe pneumonia can develop despite appropriate antibiotic therapy. We studied the effects of methylprednisolone pulse therapy on severe refractory M. pneumoniae pneumonia in children. Methods The clinical effects of methylprednisolone therapy were evaluated retrospectively in 12 children with severe refractory M. pneumoniae pneumonia, which was diagnosed serologically. All patients developed respiratory distress, high fever, and initial lobar pneumonic consolidation based on radiological findings. All clinical symptoms deteriorated despite appropriate antibiotic therapy. Thus, children were treated with intravenous methylprednisolone pulse therapy in addition to antibiotics. Results The average febrile period before admission was 4.9±1.7 days, and fever persisted in all children until steroid administration. Methylprednisolone pulse therapy (30 mg/kg) was given 5.4±2.5 days after admission. After methylprednisolone pulse therapy, clinical symptoms improved in all patients without adverse events. The fever subsided 0-2 h after initiation of corticosteroid therapy. The abnormal radiological findings resolved within 2.6±1.3 days, and the high C-reactive protein levels (6.7±5.9 mg/dL) on admission decreased to 1.3±1.7 mg/dL within 3.0±1.1 days after starting corticosteroid therapy. Conclusions Three-day methylprednisolone pulse therapy could be applied to treatment of refractory M. pneumoniae pneumonia despite appropriate antibiotic therapy and appeared to be efficacious and well-tolerated.