An Unusual Cluster of Roseomonas mucosa Cases in a Hospital System: Related or Not?

Roseomonas mucosa is considered an opportunistic pathogen and the majority of R. mucosa cases are bacteremia in patients with a malignancy. Our clinical microbiology laboratory noticed an unusual trend of four R. mucosa -positive cultures (two blood, one abscess and one corneal swab) from four separate patients within a period of 45 days. To determine if the four isolates were related, whole genome sequencing (WGS) and single nucleotide polymorphism (SNP) analysis were performed. WGS analysis demonstrated >4000 SNPs between the isolates suggesting they were not related. Here we present a case series of four separate patients with R. mucosa -positive cultures , and collaboration between the clinical microbiology laboratory and state public health department to use WGS for assessing the relatedness of R. mucosa isolates.