Paediatric parapneumonic effusion - a twenty-year clinical narrative.

Purpose Paediatric parapneumonic effusion (PPE) is accompanied by an increased risk of complications, e.g., sepsis or lung sequelae. Treatment strategies span from antibiotics alone to surgical interventions, but an internationally accepted guideline is lacking. With this study, we aim to better understand how management strategies influence short-term outcome parameters, like length of stay, antibiotic treatment duration, and lung damage. Methods Retrospective observational single-centre study. Patients admitted from 1 July 2004 to 30 June 2024 with PPE to our tertiary hospital were analysed. We used the exact Jonckheere-Terpstra test to analyse trends over time. Results A total of 278 patients were included, 23 (8%) had to be excluded for lack of informed consent. A majority (173/255, 68%) were treated with pleural drainage. Over time, drains were increasingly more often inserted without surgery, 20% vs. 65% (p = 0.001) in 2004-2008 vs. 2020-2024. Intravenous antibiotic treatment duration declined from 15 days in 2004-2008 to 11 days in 2020-2024, p = 0.002. The most commonly identified pathogen was S. pneumoniae (39%), followed by S. pyogenes (18%). S. pyogenes compared to S. pneumoniae was more often associated with sepsis or toxic shock (45% vs. 6%, p < 0.0001), but fewer patients showed radiologic evidence for acute lung damage (68% vs. 23%, p < 0.001). Conclusion We found considerable clinical differences in patients with PPE caused by S. pneumoniae vs. S. pyogenes. The former was associated with substantially greater lung damage.