Ralstonia mannitolilytica infection in a tertiary care centre: an outbreak report.

Background: In this paper we describe an outbreak of Ralstonia mannitolilytica infection declared in our facility between January 2021 and January 2022.

Methods: In order to identify the source of the outbreak, we applied widespread epidemiological investigation and infection control measures, including device isolation, environmental sampling, and PFGE typing.

Results: Thirty-six cases of R. mannitolilytica infection were identified, mostly adults (78%) and males (75%). Initially, neurological procedures were a common risk factor among cases, leading to sampling of related environmental settings. Cases with other medical procedures started to be reported. The PFGE results showed most R. mannitolilytica isolates were indistinguishable which expanded our investigation to all hospital areas. The infection source was discovered later as a single lot number of sodium chloride solution that had been used in practice. The contaminated solution was recalled from all hospital units and the findings were reported to the Saudi FDA to communicate with the manufacturer and other healthcare organizations involved. No new cases of R. mannitolilytica were identified thereafter.

Conclusion: Our findings indicate that identifying the source of an outbreak could be challenging. An extended incubation period might be considered to improve and accelerate the identification of R. mannitolilytica. In order to minimize similar incidents, it is essential to regularly monitor the compliance of manufacturers and suppliers with regulations related to the safety of solutions administered in medical practice.