Intravenous vs intravenous plus aerosolized colistin for treatment of ventilator-associated pneumonia - a matched case-control study in neonates

Background Recently intravenous (IV) and aerosolized (ASZ) colistin have been used for treating ventilator-associated pneumonia (VAP) due to colistin susceptible multidrug-resistant Gram-negative bacteria (MDR-GNB). Colistin has limited lung penetration. We compared the efficacy and safety of IV-alone versus IV+ASZ-colistin for treating VAP in neonates. Methods This retrospective matched case-control study was performed at NICU of the Aga Khan University Hospital, Pakistan between January 2015 and December 2018. Sixteen neonates with MDR-GNB associated VAP received IV-ASZ-colistin and were matched for date of birth, gestational age, birth weight, Apgar score, antenatal steroid history, disease severity, and duration of mechanical ventilation with 16 control neonates who received IV-colistin alone. Results Both groups had similar MDR-GNB isolates andAcinetobacter baumannii(78%) was the most common pathogen. No colistin-resistant strain was isolated. Duration of IV-colistin and concomitant antibiotics use was significantly (p< 0.05) shorter in the IV-ASZ-colistin group. Significantly (p< 0.05) higher clinical cure and microbial eradication, along with lower ventilatory requirements, mortality rate, and colistin induced nephrotoxicity and electrolyte imbalance was observed in the IV-ASZ-colistin group. Conclusions With better lung penetration, ASZ-colistin offers effective and safe microbiological and clinical benefits as adjunctive or alternate treatment of VAP due to colistin susceptible MDR-GNB in neonates.