Osteomyelitis associated with infection in a young cat

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. and DNA was amplified by PCR from peripheral blood. Indirect immunofluorescence documented strong immunoreactivity, with lower subspecies and antibody titers. After the administration of doxycycline and pradofloxacin for suspected -induced osteomyelitis, lameness resolved rapidly. Six-week post-treatment radiographs identified healing of the affected bone, and species enrichment blood culture was negative. antibody titers decreased four-fold over a year, supporting seroreversion. Relevance and novel information: is a flea-transmitted, host-adapted species, not previously implicated as a cause of osteomyelitis in cats. 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 infection in a cat