Klebsiella pneumoniae in pediatric respiratory infections: a targeted next-generation sequencing study on co-infection patterns, clinical profiles, and outcomes.

Aims: Klebsiella pneumoniae (KP) is a key pediatric respiratory pathogen, yet comprehensive studies on its clinical profiles and co-infections are limited. This study characterizes KP detection dynamics, clinical features, and outcomes in hospitalized children using targeted next-generation sequencing (tNGS).

Methods and results: A retrospective tNGS analysis of 5021 pediatric respiratory infection cases identified KP in 6.3% (314/5021), predominantly infants aged <1 year (58.0%) with male predominance (1.8:1). Co-infections occurred in 97.4% (306/314), primarily KP-viral-bacterial combinations (63.7%) featuring Acinetobacter baumannii (47.5%), cytomegalovirus (33.8%), and rhinovirus (28.0%). Multivariate analysis identified seven independent intensive care unit (ICU) predictors: younger age [odds ratio (OR): 0.971], reduced lymphocyte percentage (OR: 0.894), elevated lactate dehydrogenase (OR: 1.006), prolonged fever duration (OR: 1.248), bronchial wall thickening (OR: 3.717), respiratory complications (OR: 20.112), and multi-system complications (OR: 2.868). Respiratory complications affected 37.6% (118/314), with 37.9% (119/314) having multi-organ involvement. Despite 43.3% requiring respiratory support (including 11.5% invasive ventilation), 92.0% achieved full recovery with zero mortality. Median hospitalization was 7 days (interquartile range:6-11).

Conclusion: KP causes significant polymicrobial respiratory infections in infants, with tNGS effectively revealing complex co-infection patterns. Early identification of pathogens and these ICU predictors may optimize ICU triage and treatment strategies.