Relationship Between Degenerative Joint Disease, Pain, and Bartonella spp. Seroreactivity in Domesticated Cats

BACKGROUND Recently, a potential association was identified between Bartonella exposure and arthritides in mammalian species other than cats. HYPOTHESIS/OBJECTIVES We hypothesized that Bartonella exposure is associated with more severe degenerative joint disease (DJD) and a greater burden of DJD-associated pain in client-owned cats. ANIMALS Ninety-four client-owned cats (6 months to 20 years old), ranging from clinically unaffected to severely lame because of DJD. METHODS Using physical examination and radiography, pain and radiographic scores were assigned to each part of the bony skeleton. Sera were tested for Bartonella henselae, B. koehlerae, and B. vinsonii subsp. berkhoffii (genotypes I, II, and III) antibodies using immunofluorescence antibody assays. Variables were categorized and logistic regression used to explore associations. RESULTS Seropositivity to Bartonella was identified in 33 (35.1%) cats. After multivariate analysis controlling for age, total DJD score (OR, 0.51; 95% CI, 0.26-0.97; P = .042), appendicular pain score (OR, 0.33; 95% CI, 0.17-0.65; P = .0011), and total pain score (OR, 0.35; 95% CI, 0.17-0.72; P = .0045) were significantly inversely associated with Bartonella seroreactivity status, indicating that cats with higher DJD and pain scores were less likely to be Bartonella seropositive. CONCLUSIONS AND CLINICAL IMPORTANCE Based upon this preliminary study, Bartonella spp. seropositivity was associated with decreased severity of DJD and decreased DJD-associated pain in cats. Additional studies are needed to verify these findings, and if verified, to explore potential mechanisms.