Detection of Bartonella infection in pet dogs from Manila, the Philippines

Dogs can be infected by a wide range of Bartonella spp., but studies regarding the prevalence of Bartonella infection in dogs in the Philippines have not been conducted. This study aimed at determining the prevalence of Bartonella infection in pets dogs from two veterinary clinics in Metro Manila, The Philippines, using both serology and polymerase chain reaction (PCR). Blood samples from 116 dogs from two different groups, one of 60 mainly "healthy dogs" and the other one of 56 dogs enrolled in a tick-borne disease suspect group, were tested for presence of B. henselae antibodies and to detect Bartonella DNA using primers specific for the citrate synthase gene. Seroprevalence for B. henselae was very low (2.6%), as the only three (5%) seropositive dogs (titer 1:64) where among the healthy pet dog group. Following subsequent sequencing, 13 samples, all from the tick-borne disease group, were determined positive for B. henselae (11.2%). This is the first study to report dog infection with B. henselae in the Philippines.

Testing for Bartonella ssp. DNA in cerebrospinal fluid of dogs with inflammatory central nervous system disease

BACKGROUND

Neurobartonellosis occurs in people. The role these organisms might play in inflammatory brain disease of dogs is unclear.

HYPOTHESIS/OBJECTIVES

That Bartonella spp. DNA would be amplified more commonly from the CSF of dogs with inflammatory disease compared to those with noninflammatory disease. To report the prevalence of Bartonella spp. in dogs with and without inflammatory CNS disease with a commercially available PCR assay.

ANIMALS

Cerebrospinal fluid (CSF) samples from 172 dogs from either Washington State University or Colorado State University.

METHODS

Retrospective study. A search was performed of all medical records from dogs with CSF samples submitted to CSU's Center for Companion Animal Studies or Veterinary Diagnostic Laboratory from CSU or WSU for Toxoplasma or Neospora PCR assay. Increased CSF nucleated cell counts and an adequate volume of CSF must have been present to evaluate Bartonella spp. by PCR assay.

RESULTS

Inflammatory CNS disease was confirmed in 65 dogs, none of which were positive for Bartonella spp. DNA. Of the other 107 dogs, one was positive for B. henselae DNA. The CSF from this dog contained red blood cells.

CONCLUSIONS AND CLINICAL IMPORTANCE

Failure to amplify Bartonella spp. DNA from the CSF of the dogs with inflammatory disease suggests the organism was not involved in the etiology of the disease, the organism was in the CNS tissues but not in the CSF, or the organism was present but in quantities undetectable by this PCR assay. The combination of PCR and culture is the most sensitive way to detect Bartonella spp. and the use of that technique should be considered in future studies.