Changing Trends of Ralstonia Bacteremia in Patients at a Tertiary Care Center in North India: A 2-Year Retrospective Analysis

Am J Trop Med Hyg. 2024 Dec 10:tpmd240421. doi: 10.4269/ajtmh.24-0421. Online ahead of print.

Abstract

Ralstonia species are recently emerging as pathogens of human importance. This study was performed to assess the distribution of Ralstonia species among bacteremia patients and the clinical and demographical factors of these patients. This retrospective observational study was performed in the Microbiology Department of a tertiary care center in North India from April 2022 to April 2024. All in-patients with blood cultures positive for Ralstonia species for the first time during the study period were included in the study. Positive blood cultures were inoculated on blood and MacConkey agar. Identification was done by matrix-assisted laser desorption ionization-time of flight mass spectrometry, and antibiotic sensitivity testing was determined by disc diffusion assay. During the study period, 26 isolates of Ralstonia species were identified. R. mannitolilytica was the predominant isolate, followed by R. pickettii. Most patients with Ralstonia bacteremia belonged to the age group of <60 years (n = 20; 78%). The median age of the study population was 62 years. The male-to-female ratio was 1.6:1. Most of the patients presented with complaints of fever (77%), followed by epigastric pain (38.4%). Among the underlying comorbidities, most of the patients with Ralstonia bacteremia had sepsis (73%), followed by multiorgan dysfunction syndrome (30.7%). None of the R. mannitolilytica isolates showed sensitivity to imipenem, meropenem, aztreonam, and ceftazidime. On comparing both the isolates, R. pickettii showed better sensitivity to amikacin, imipenem, meropenem, aztreonam, and ceftazidime than R. mannitolilytica. Overall mortality of the patients in the study was 22% (n = 6).