The exact etiopathogenesis of SRMA is unknown ( Tipold 2000 ). Activated T cells have been demonstrated in dogs with SRMA, indicating potential contact with an antigenic stimulus; however, no bacterial or viral agents have been identified to date ( Tipold and others 1996 ). A Th2-mediated immune response is most likely, based on the presence of high CD4:CD8a ratios and a high proportion of B cells in peripheral blood and CSF. A Th2-mediated immune response is further supported by the expression of low levels of Th1-response-related cytokines (IL-2, IFN-γ) and upregulation of Th2 cytokines (IL-4) in blood and CSF in dogs with the acute form of SRMA ( Schwartz and others in press ). This Th2-mediated immune response leads to an upregulation of the humoral immune response and excessive IgA production ( Schwartz and others 2008b ).
Conclusions The clinical, laboratory, and radiologic findings associated with SREAT are more varied than previously reported. Misdiagnosis at presentation is common. This treatable syndrome should be considered even if the serum sensitive thyroid-stimulating hormone level and erythrocyte sedimentation rate are normal, the cerebrospinal fluid profile does not suggest an inflammatory process, and neuroimaging results are normal. Until the pathophysiologic mechanism of this and other autoimmune encephalopathies is better characterized, we believe that descriptive terms that reflect an association rather than causation are most appropriate for this syndrome.
A diagnosis is normally made on the basis of first excluding other causes of spinal pain (like bone or soft tissue infections, immune-mediated joint disease, infections) by obtaining a blood sample and performing radiographs. Then, cerebro-spinal fluid (CSF) analysis is performed by obtaining a sample of CSF from the neck or lower spine (or both) in a sterile manner under general anaesthesia . Your pet will have dedicated one-to-one care during their CSF tap by one of our nurses from the prep nursing team who are trained and experienced in anaesthesia and sedation . The demonstration of inflammation and the presence of a specific type of inflammatory cell facilitate a presumptive diagnosis. Although infection is very unlikely, we will normally run a panel of various blood and urine tests to exclude this possibility.