Myelitis due to reactivated spinal toxoplasmosis in a cat

The diagnosis, management, and subsequent post-mortem confirmation of a case of suspected reactivated spinal toxoplasmosis in a 10-year-old female neutered Cornish Rex are described. While an ante-mortem diagnosis of toxoplasmosis was considered possible based on the neuroanatomical diagnosis of central nervous system (CNS) disease primarily involving spinal cord segment C6-T2 and the progressive elimination of other potential causes, Toxoplasma gondii antibody titres were consistent with previous exposure rather than active infection. A poor response to appropriate therapy did not support a diagnosis of toxoplasmosis. A post-mortem morphological diagnosis of marked segmental non-suppurative myelitis and necrosis, and an aetiological diagnosis of toxoplasmosis were made. The clinical and pathological findings are supportive of CNS inflammation due to reactivation of latent tissue T gondii cysts.