Bloodstream Infections Caused by Drug Resistant Ralstonia species: A Case Series During the COVID-19 Pandemic

Ralstonia spp. is an emerging, non-fermentative Gram-negative rod that demonstrates multidrug resistance. Herein, four cases of bloodstream infections (BSI) caused by R. mannitolilytica or R. pickettii are presented. All the cases had comorbidities that predisposed them to this opportunistic infection. The microbiological assessment showed carbapenemase genes carried out in two strains with minimal inhibitory concentrations > 32 μg/mL to imipenem and meropenem. Fluoroquinolones and trimethoprim-sulphamethoxazole were the most potent agents showing activity against 3/4 strains (75%), although treatment should be susceptibility-dependent for each strain. This case series highlights the possibility of co-infection by a rare organism during the COVID-19 pandemic and the importance of the readiness of diagnostic laboratories to support the diagnosis of uncommon pathogens.