Prevalence of Bartonella spp. in Canine Cutaneous Histiocytoma.

Canine cutaneous histiocytoma (CCH) is a common, benign neoplastic proliferation of histiocytes of Langerhans cell origin that often ulcerate, become secondarily infected and regress spontaneously. Bartonella is a fastidious genus of facultative intracellular pathogens that can be transmitted through arthropod bites and epidermal animal scratches and has been identified previously in the cytoplasm of histiocytes within granulomatous lesions and in skin biopsy samples of inflammatory pustules and papules. Based on the established inflammatory and oncogenic properties of Bartonella, we hypothesized that Bartonella spp. DNA could be amplified from CCH more often than from non-lesional skin and bacteria could be localized within skin tumours using indirect immunofluorescence (IIF). Paraffin wax-embedded surgical biopsy samples from dogs with CCH and non-neoplastic skin adjacent to osteosarcomas (control group selected due to wide surgical margins) were retrieved from the archive of the pathology service of North Carolina State University College of Veterinary Medicine. DNA was extracted and regions of the 16S-23S rRNA intergenic transcribed spacer (ITS) region and the pap31 and gltA genes were amplified by polymerase chain reaction (PCR) using Bartonella-specific primers. IIF was performed using a primary Bartonella henselae monoclonal antibody to localize B. henselae in tissues of PCR-positive dogs. Bartonella vinsonii subsp. berkhoffii was amplified from 1/17 (5.8%) control tissues and B. henselae was amplified from 4/29 (13.8%) CCH tissues. The prevalence of B. vinsonii subsp. berkhoffii (P = 0.37) or B. henselae (P = 0.28) did not vary statistically between study groups. B. henselae could be visualized in 2/4 (50.0%) CCH tissues using IIF. Based on this study, Bartonella spp. are unlikely to cause CCH.

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.

Intraoperative bleeding in dogs from Grenada seroreactive to Anaplasma platys and Ehrlichia canis.

BACKGROUND: Frequent exposure of Grenadian dogs to Rhipicephalus sanguineus results in Anaplasma platys, and Ehrlichia canis seroreactivity. During elective surgeries, substantial intraoperative hemorrhage occurs in some seroreactive dogs. OBJECTIVES: To assess hemostatic parameters and bleeding tendencies as well as prevalence of PCR positivity in apparently healthy A. platys and E. canis seroreactive and seronegative free-roaming dogs from Grenada. ANIMALS: Forty-seven elective surgery dogs allocated to 4 groups: Seronegative control (n = 12), A. platys (n = 10), E. canis (n = 14) and A. platys, and E. canis (n = 11) seroreactive. METHODS: Preoperatively, hemostasis was assessed by platelet count, prothrombin time, activated partial thromboplastin time, and buccal mucosal bleeding time. Intra- and postoperative bleeding scores were subjectively assigned. Blood, spleen, bone marrow, and lymph node aspirates were tested by PCR. RESULTS: Bleeding scores in dogs coseroreactive for A. platys and E. canis were higher (P = .015) than those of seronegative dogs. A. platys DNA was amplified from 7/21 (33%) A. platys seroreactive dogs and from 1 E. canis seroreactive dog; E. canis DNA was amplified from 21/25 (84%) E. canis seroreactive dogs. E. canis DNA was amplified most often from blood, whereas A. platys DNA was amplified most often from bone marrow. CONCLUSIONS AND CLINICAL IMPORTANCE: Apparently healthy, free-roaming dogs coseropositive for A. platys and E. canis may have increased intraoperative bleeding tendencies despite normal hemostatic parameters. Future investigations should explore the potential for vascular injury as a cause for bleeding in these dogs. Improved tick control is needed for dogs in Grenada.