Septic arthritis due to Roseomonas gilardii in an immunocompetent adolescent

1 Department of Medical Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada 2 Department of Pediatrics, Dalhousie University, Halifax, Nova Scotia, Canada 3 Department of Clinical Microbiology, Health Sciences Centre, Diagnostic Services of Manitoba, Winnipeg, Manitoba, Canada Correspondence Sergio Fanella sfanella{at}hotmail.com Received March 18, 2009 Accepted June 30, 2009 The genus Roseomonas comprises groups of slow-growing, Gram-negative coccobacilli, which only infrequently cause infection in humans. When identified, they are associated with immunocompromised adults, often causing bacteraemia. Due to their rarity, members of this genus can be overlooked or misidentified using automated laboratory identification systems. We report on an immunocompetent adolescent patient who developed septic arthritis due to Roseomonas gilardii following surgery for a sports injury. The isolate was initially misidentified as Bordetella bronchiseptica using the Vitek 2 system, but confirmed as R. gilardii based on 16S rRNA gene sequencing. To the best of our knowledge, this is the first case of a healthy paediatric patient with septic arthritis due to R. gilardii . Images of R. gilardii grown on different agars are available as supplementary data with the online version of this paper.