Aim: The aim of the study was to find clinical predictors for parapneumonic empyema in children.

Methods: Thirty-seven children treated for parapneumonic empyema at the Department of Pediatrics, Turku University Hospital, were retrospectively evaluated. Two distinct comparison groups of children with uncomplicated community-acquired pneumonia with alveolar consolidation (n = 37 in both groups) were included. Clinical and laboratory data on admission as well as fever kinetics and inflammatory markers during hospitalization were analyzed.

Results: In a multivariate analysis, a history of prolonged fever, tachypnoea and pain on abdominal palpation on admission were the most significant clinical predictors for empyema. On admission, serum C-reactive protein levels were higher among children with empyema than among those with uncomplicated pneumonia (means, 234 mg/L vs. 178 mg/L; p = 0.037). During hospitalization, prolonged fever and persistence of high serum C-reactive protein levels were associated with empyema. At the initial evaluation, pleural fluid was not reported in 35% of children with empyema.

Conclusions: Early recognition of developing empyema is challenging. Children with pneumonia presenting with prolonged fever, tachypnoea, pain on abdominal palpation and high serum C-reactive protein levels are at risk for parapneumonic empyema.