Increased prevalence of Borrelia burgdorferi infections in Bernese Mountain Dogs: a possible breed predisposition

BACKGROUND: Glomerulonephritis in dogs has been associated with B. burgdorferi infections. In Bernese Mountain Dogs with glomerulonephritis antibodies against B. burgdorferi were found in most dogs, raising the question if the breed is predisposed to infections with B. burgdorferi. The aim of this study was to determine the prevalence of antibodies against B. burgdorferi sensu lato in a well defined population of Bernese Mountain Dogs and to compare this prevalence with data from dogs of other breeds. RESULTS: 160 Bernese Mountain Dogs and 62 control dogs (large breed dogs with long hair) were included. All dogs were considered healthy according to a questionnaire filled out by the owner, complete blood count, chemistry panel, urinalysis and urine culture. Bernese Mountain Dogs and control dogs were kept similar in similar environments. Seroprevalence of B. burgdorferi was assessed by ELISA and Western blot and was 58% in Bernese Mountain Dogs compared to 15% in control dogs. This difference was significant. Neither antibodies against leptospires nor vaccination or hair coat color influenced the results. CONCLUSIONS: The cause of the considerably higher prevalence of antibodies against B. burgdorferi in Bernese Mountain Dogs and its consequences are not known. A breed predisposition can be suspected

Follow-up of Bernese Mountain dogs and other dogs with serologically diagnosed Borrelia burgdorferi infection: What happens to seropositive animals?

<p>Abstract</p> <p>Background</p> <p>Data on the long-term outcome of <it>B. burgdorferi </it>infections in adult dogs are sparse. The aim of the present study was to investigate whether Bernese Mountain dogs with serological evidence of natural <it>B. burgdorferi </it>infection more often develop signs such as lameness, azotemia or proteinuria during a follow-up period of 2.5 to 3.0 years. Seropositive Bernese Mountain dogs were compared to seronegative Bernese Mountain dogs and to seropositive and seronegative control dogs of other breeds.</p> <p>Dogs included in a previous study on the prevalence of antibodies against <it>B. burgdorferi </it>in Bernese Mountain dogs were re-evaluated. Antibodies against <it>B. burgdorferi </it>were determined using an ELISA with a whole-cell sonicate as antigen and results were confirmed using a Western blot assay.</p> <p>Results</p> <p>Fifty-three Bernese Mountain dogs and 30 control dogs were re-evaluated. Re-evaluation was performed between 2.5 and 3.0 years (median 2.7 years) after the first assessment.</p> <p>The age of the dogs at the second evaluation ranged from 3 to 11 years (median 6 years). There were no significant differences with regard to poor general condition or lameness between the first and the second evaluation.</p> <p>At the first evaluation 22 (42%) of the Bernese Mountain dogs and 11 (37%) of the control dogs were considered positive for antibodies against <it>B. burgdorferi</it>. At the second evaluation 25 (47%) of the Bernese Mountain dogs and 12 (40%) of the control dogs were considered positive; 69% of the dogs showed the same serological result at both examinations and 31% were seroconverted or seroreverted. During the first examination, azotemia was diagnosed in 6 Bernese Mountain dogs and during the second examination in 11 Bernese Mountain dogs. No control dogs had azotemia in this study. In seropositive dogs there was no increase in lameness or signs of renal disease over time.</p> <p>Conclusion</p> <p>It may be concluded that antibodies against <it>B. burgdorferi </it>determined by whole cell ELISA and confirmed by Western blot were neither associated with the development of lameness nor with signs of renal disease like azotemia or proteinuria in dogs observed over a period of 2.5 to 3.0 years.</p