Background: The aim of this case-control study was to analyse the clinical characteristics of children with recurrent community-acquired pneumonia (rCAP) affecting different lung areas (DLAs) and compare them with those of children who have never experienced CAP in order to contribute to identifying the best approach to such patients.
Methods: The study involved 146 children with ≥2 episodes of radiographically confirmed CAP in DLA in a single year (or ≥3 episodes in any time frame) with radiographic clearing of densities between occurrences, and 145 age- and gender-matched controls enrolled in Milan, Italy, between January 2009 and December 2012. The demographic and clinical characteristics of the cases and controls were compared, and a comparison was also made between the cases with rCAP (i.e. ≤3 episodes) and those with highly recurrent CAP (hrCAP: i.e. >3 episodes).
Results: Gestational age at birth (p = 0.003), birth weight (p = 0.006), respiratory distress at birth (p < 0.001), and age when starting day care attendance (p < 0.001) were significantly different between the cases and controls, and recurrent infectious wheezing (p < 0.001), chronic rhinosinusitis with post-nasal drip (p < 0.001), recurrent upper respiratory tract infections (p < 0.001), atopy/allergy (p < 0.001) and asthma (p < 0.001) were significantly more frequent. Significant risk factors for hrCAP were gastroesophageal reflux disease (GERD; p = 0.04), a history of atopy and/or allergy (p = 0.005), and a diagnosis of asthma (p = 0.0001) or middle lobe syndrome (p = 0.001). Multivariate logistic regression analysis, adjusted for age and gender, showed that all of the risk factors other than GERD and wheezing were associated with hrCAP.
Conclusions: The diagnostic approach to children with rCAP in DLAs is relatively easy in the developed world, where the severe chronic underlying diseases favouring rCAP are usually identified early, and patients with chronic underlying disease are diagnosed before the occurrence of rCAP in DLAs. When rCAP in DLAs does occur, an evaluation of the patients' history and clinical findings make it possible to limit diagnostic investigations.