Bartonella are gram-negative, facultative intracellular bacteria which are transmitted by fleas and ticks. Bartonella henselae is mostly known as the causative agent of “cat-scratch disease” in humans. Infections in cats are predominantly subclinical. Fever, muscular pain, local lymphadenopathy and, rarely, also neurological symptoms can occur, which usually disappear again after a few days. Recently, the involvement of Bartonella henselae in gingivitis and stomatitis in cats has been discussed more frequently. Pathogen detection and antibody detection often do not match and a definitive diagnosis is linked to the detection of the pathogen. A negative PCR result does not exclude an infection with B. henselae and should be repeated in case of clinical suspicion.
Dogs, too, can occasionally be affected by Bartonella infection. The disease can cause endocarditis, recurrent granulomatous lymphadenitis, systemic granulomatous processes and meningitis.