Ralstonia pickettii outbreak in pediatric intensive care units, Peru-2025.

OBJECTIVE

Ralstonia spp. are opportunistic gram-negative bacilli that persist in aqueous environments and may cause nosocomial outbreaks. We describe an outbreak of bloodstream infections by Ralstonia pickettii associated with contaminated dexmedetomidine.

METHODS

Outbreak investigation, including a case-control study, was conducted in a tertiary pediatric hospital (July 19-August 23, 2025), affecting the Cardiovascular, Pediatric, and Burn Intensive Care Units. Species identification was performed using MALDI-TOF MS. Whole-genome sequencing evaluated clonality and phylogenetic relationships with previously reported outbreaks. Environmental sampling and traceability of medical products identified the outbreak source.

RESULTS

Eleven R. pickettii bloodstream infections were identified, with 72.73% occurring in the Cardiovascular ICU. The median patient age was 6 months (IQR: 2 mo-7 yr), and fever was the predominant symptom (72.73%). The attack rate was 29.73%, and the case fatality rate was 27.27%. Significant risk factors included exposure to the implicated dexmedetomidine batch (OR 18.75, 95% CI 2.02-173.00, P = .01) and higher dispensed quantity of dexmedetomidine (OR 1.33, 95% CI 1.07-1.67, P = .01). Genomic analysis confirmed clonal R. pickettii (rST-37,889) with close phylogenetic relatedness to outbreaks in Germany and Australia in 2023. All isolates harbored blaOXA-60, blaOXA-22, adeF, and vanH resistance genes. Identical R. pickettii was isolated from the implicated imported dexmedetomidine batch. The outbreak was controlled following withdrawal of the contaminated batch.

CONCLUSIONS

This first reported outbreak of R. pickettii bloodstream infections linked to intrinsically contaminated dexmedetomidine highlights risks from manufacturing failures in global pharmaceutical supply chains and emphasizes the essential role of genomic surveillance in outbreak investigation.