Long-term recovery after parapneumonic empyema in children.

Background: The incidence of parapneumonic empyema in children has increased worldwide, but the long-term anatomical and functional consequences in the lungs after empyema are not known.

Methods: We investigated the long-term outcome of childhood empyema in 26 patients by physical examination, chest radiograph and magnetic resonance image (MRI) of the lungs, and pulmonary function tests.

Results: At follow-up 3-19 years (mean 8 years) after empyema, all patients had normal findings in the physical examination. Spirometry was normal in 80% of patients, and evidence of obstructive airway disease was detected in 16%. Thirty-six percent of patients had abnormal findings in the chest radiograph and 92% in the MRI of the lungs. In six patients, the MRI revealed significant pleural scarring (extension longer than 1 cm). Thirteen patients (50%) reported persistent respiratory symptoms, such as impaired tolerance of physical activity or prolonged cough after a common cold. During the follow-up four patients suffered a second pneumonia.

Conclusions: The long-term recovery of children with parapneumonic empyema is good, since most patients subsequently have normal lung function, chest radiograph, and clinical recovery. Half of the patients reported subjective respiratory symptoms and most patients had minor lung abnormalities, mostly pleural scars, detected in the MRI many years after empyema. However, as long-term impairment of lung function was rarely found, the clinical significance of the anatomical residues seen in the lung MRI seems to be minor.