Ocurrence of anti-Toxoplasma gondii and Ehrlichia canis antibodies in dogs with nervous alterations assisted at a veterinary teaching hospital

Toxoplasmosis is a zoonotic disease caused by Toxoplasma gondii. Most often, the disease is asymptomatic in dogs due to effectiveness of the immune system. By the way, numerous clinical signs can be triggered, including neuromuscular like ataxia, circling, behavioral changes, seizures, spasms and tremors. The disease usually manifests itself after immune depression, and, for this reason, usually may be associated to immunosuppressive infections, like by distemper virus and Ehrlichia canis. E. canis is an obligatory intracellular rickettsia of mature or immature hematopoietic cells and canine monocytes, and the etiologic agent of Canine Monocytic Ehrlichiosis (CME). Like toxoplasmosis, CME may cause nervous signs as well. This study aims to estimate the occurrence of anti- T. gondii and anti- E. canis antibodies and characterize nervous syndromes in dogs with nervous alterations assisted at a veterinary teaching hospital. From May 2010 to December 2011, dogs with nervous alterations assisted at HOVET-UFMT were submitted to neurological evaluation for determining nervous syndromes. Serum and whole blood samples were collected for performing indirect immunofluorescence test (IFAT) for T. gondii and E. canis and hematological evaluation. Prevalence of 10,3 and 94,8% were observed for T. gondii and E. canis, respectively. The most frequent syndrome was multifocal, occurring in 53,5% of the cases, followed by spinal cord alterations in 22,4%, cerebral alterations in 10,3%, paroxysmal syndrome in 10,3% and neuropathic syndrome in 3,5% of the cases. There was no statistical significance between the variables analyzed (titration to T. gondii, E. canis and nervous syndromes). In conclusion, the occurrence of coinfection with T. gondii and E. canis may contribute to toxoplasmosis clinical manifestation, due to opportunist character of the parasite in order to the establishment of disease.