Association between hospitalised childhood pneumonia and follow-up chest radiographs in high-risk populations: a secondary analysis of a multicentre randomised controlled trial.

Objective: As children hospitalised with community-acquired pneumonia (CAP) are at risk of persistent chest radiograph (CXR) abnormalities and respiratory sequelae, we investigated factors associated with incomplete CXR resolution at 4 weeks and 12 months post-discharge in children from populations at high-risk of chronic lung disease.

Design: Secondary analysis-multicentre, placebo-controlled, randomised controlled trial.

Settings and patients: 324 children aged 3 months to ≤5 years hospitalised with radiographic-confirmed CAP were enrolled from seven hospitals in Australia, New Zealand and Malaysia. After 1-3 days of intravenous antibiotics, then 3 days of oral amoxicillin-clavulanate, they were randomised to extended (13-14 days) or standard (5-6 days) courses of antibiotics.

Intervention: CXRs were performed at admission, 4 weeks, and 12 months post-discharge and reviewed in a blinded manner.

Main outcome measures: Radiographic changes of pneumonia at 4 weeks and 12 months post-discharge compared with admission CXRs.

Results: Among children with interpretable CXRs, incomplete resolution was seen in 42/253 (17%) at 4 weeks, and 29/212 (14%) at 12 months. Characteristics at admission associated with incomplete CXR resolution at 4 weeks were previous pneumonia hospitalisation (adjusted odds ratio [OR_adj])=6.46, 95% confidence interval [CI] 2.21 to 18.85) and increasing age (OR_adj=0.60 per-year, 95% CI 0.38 to 0.94). Continuing respiratory symptoms/signs at 4 weeks post-discharge was also associated with incomplete resolution (OR=5.63, 95% CI 2.38 to 13.32). At 12 months, previous pneumonia hospitalisation was associated with persistent incomplete CXR resolution (OR=4.03, 95 % CI 1.25 to 13.02).

Conclusion: In high-risk settings, younger age, those with previous pneumonia hospitalisation, or ongoing respiratory symptoms/signs 4 weeks post-discharge from hospitalised CAP may be associated with incomplete CXR resolution. Consequently, follow-up imaging and monitoring may be warranted in these children.