Central line-related bacteremia due to Roseomonas mucosa in a patient with diffuse large B-cell non-Hodgkin's lymphoma.

A 42-year-old male patient with a history of diffuse large B-cell non-Hodgkin's lymphoma (DLBCL) developed a central line-related bacteremia due to the presence of a Gram-negative bacillus, which was difficult to identify conventionally. Sequencing of a partial region of the 16S rRNA gene identified the organism as Roseomonas mucosa with a homology score of 100% with 1003 bases called. Due to difficulties with the phenotypic identification of this genus, coupled with its emergence in line-related bacteremia in hematology patients with malignancy, Roseomonas spp. should be considered in cases of line-related infection in such patients with atypical Gram-negative organisms. Although several cases have been reported in the literature of line-related sepsis due to Roseomonas gilardii, only a few cases have been reported of Roseomonas mucosa infection in patients with hematological malignancy. This report highlights the benefits of the integration of a sequence-based typing approach in the identification of difficult-to-identify bacterial isolates employing partial regions of the 16S rRNA gene. Continued routine adoption of such techniques by clinical diagnostic laboratories may prove beneficial for the correct identification of blood-borne infections, as well as for the correct epidemiological characterization of unusual causal agents of bacteremia in immunocompromised individuals.