Osteomyelitis associated with Bartonella henselae infection in a young cat

Abstract

Case summary A 1-year-old male intact domestic shorthair cat was evaluated for acute onset non-weightbearing left forelimb lameness and generalized peripheral lymphadenopathy. CT identified a monostotic aggressive bone lesion with an incomplete fracture of the left radial metaphysis. Bone aspirates yielded osteoblasts with minimal nuclear atypia. Abdominal ultrasound revealed a nodular spleen and lymphadenopathy; cytologically, both contained lymphoid hyperplasia. A urine histoplasma antigen test was negative. Bartonella henselae and Mycoplasma haemominutum DNA was amplified by PCR from peripheral blood. Indirect immunofluorescence documented strong B henselae immunoreactivity, with lower Bartonella vinsonii subspecies berkhoffii and Bartonella koehlerae antibody titers. After the administration of doxycycline and pradofloxacin for suspected Bartonella -induced osteomyelitis, lameness resolved rapidly. Six-week post-treatment radiographs identified healing of the affected bone, and Bartonella species enrichment blood culture was negative. B henselae antibody titers decreased four-fold over a year, supporting seroreversion. Relevance and novel information B henselae is a flea-transmitted, host-adapted species, not previously implicated as a cause of osteomyelitis in cats. B henselae subclinical bacteremia is highly prevalent among cats; however, bacteremia has been associated with lymphadenopathy and febrile illness in cats. This report describes a unique clinical presentation in association with B henselae infection in a cat.

Pradofloxacin for Treatment of Bartonella henselae in Experimentally Inoculated Cats

“…in some cats. Fever, cardiac abnormalities, and hyperglobulinemia are some of the most common [ 1 , 3 , 4 , 5 , 6 , 7 , 8 , 9 ]. Several antibiotic protocols used for the treatment of B. henselae infection in cats, including doxycycline, azithromycin, or enrofloxacin administered alone, have failed to clear bacteremia in treated cats [ 3 , 4 , 10 , 11 ].…”

“…Since B. henselae is a human pathogen, in some situations (such as in the homes of immunosuppressed people) it might be desirable to eliminate bacteremia in cats. While pradofloxacin has been used in combination with doxycycline in several case reports [ 6 , 7 , 8 ], no study has assessed the safety and efficacy of a high-dose pradofloxacin protocol to eliminate B. henselae from the blood of experimentally infected cats.…”

Mixed infection of Bartonella and Eperythrozoon in a dog - case report

“…The diagnosis and treatment of a case of canine Baltons disease with ehrlichiosis admitted is described below for clinical reference (Hui J et al, 2022).…”