A systematic review of paediatric-specific risk factors for nosocomial infections in paediatric intensive care units, 2005-2024.

BACKGROUND

Children admitted to a paediatric intensive care unit (PICU) are at markedly higher risk of nosocomial infections (NIs), which correlate with elevated mortality, extended hospital stay, and amplified healthcare burden. Children exhibit distinct immunological and physiological traits compared with adult patients, highlighting an urgent need for paediatric-specific evidence to guide infection prevention. The latest existing systematic review on this topic was published in 2009, and did not cover emerging multi-drug-resistant infections (MDRIs) and modern paediatric critical care management practices. This systematic review aimed to synthesize two decades of evidence on paediatric-specific risk factors for PICU-onset NIs, encompassing all-site NIs, ventilator-associated pneumonia (VAP), catheter-associated urinary tract infections (CA-UTIs), and bloodstream infections - with central-line-associated bloodstream infections as the predominant subtype - to deliver updated evidence supporting targeted infection control strategies.

METHODS

A comprehensive electronic literature search of six databases - PubMed, Embase, Web of Science, CNKI, VIP and Wanfang - was undertaken, covering publications released between January 2005 and December 2024. Two independent reviewers completed literature screening, data extraction, and methodological quality assessment in accordance with pre-established inclusion and exclusion criteria. All eligible observational studies investigating risk factors for NIs in PICU populations were included for qualitative synthesis.

RESULTS

Overall, 24 observational studies involving 74,960 hospitalized children (2863 of whom developed NIs) were incorporated into this review. Consistent risk factors for all-site PICU NIs comprised younger age, prolonged PICU stay, invasive procedures, parenteral nutrition, glucocorticoid administration, and high severity of illness at admission (quantified via the PRISM III or PCIS scoring systems). For VAP, independent risk factors were prolonged mechanical ventilation, reintubation, and pre-existing lung disease or baseline pneumonia before initiation of ventilation. Indwelling urinary catheters constituted a core risk factor for CA-UTIs. Risk factors predictive of MDRIs included administration of two or more antimicrobial agents, coma, parenteral nutrition, and extended mechanical ventilation.

CONCLUSION

PICU-onset NIs stem from multiple modifiable risk exposures: invasive medical devices, extended intensive care hospitalization, parenteral nutrition, glucocorticoid therapy, and inappropriate overprescription of antimicrobials. Implementation of PICU-tailored infection control bundles and stratified surveillance for high-risk children is critical to reduce the incidence of NIs. Large, standardized multi-centre prospective cohorts are warranted to harmonize infection diagnostic criteria and develop optimized paediatric-specific guidelines for the prevention of NIs.

SYSTEMATIC REVIEW REGISTRATION: The review protocol was registered prospectively on PROSPERO (Registration No. CRD42025635030).