Molecular identification of Bartonella species in dogs with leishmaniosis (Leishmania infantum) with or without cytological evidence of arthritis

Recent evidence suggest that Bartonella species may cause polyarthritis and lameness in dogs. Canine leishmaniosis (CanL) due to Leishmania infantum is a multi-systemic disease often occurring in association with arthritis. We hypothesized that concurrent Bartonella infection may be a contributing factor for the development of arthritis in dogs with CanL. Hence the primary objective of this study was to investigate the molecular prevalence of Bartonella spp. in dogs with naturally occurring CanL, with or without cytologically documented arthritis. Thirty-eight dogs with CanL (31 with neutrophilic arthritis and 7 without arthritis) were retrospectively studied. Seventy-four archived clinical specimens from these 38 dogs, including 33 blood samples, 19 bone marrow (BM) samples and synovial fluid (SF) aspirates from 22 dogs were tested for Bartonella spp. DNA using the Bartonella alpha proteobacteria growth medium (BAPGM) diagnostic platform. Overall, eight (21.1%) dogs were infected with one or two Bartonella species; however, Bartonella spp. infection was not associated with arthritis in dogs with CanL. Further prospective studies are warranted to determine if there is a correlation between Bartonella spp. infection and the development of arthritis in dogs with CanL.