Equine Immunology Testing
Immunologic testing should be performed when there is a clinical history of recurrent infections and fevers, either refractory to treatment, or caused by opportunistic organisms. The history of infections supports abnormal immunologic testing findings. It is important to rule out other causes that may predispose to infections, including conditions that disrupt pathogen clearance mechanisms (e.g. stress, immunosuppressive therapy, viral infections, catheterizations, allergies, auto-immunity, lymphoma/lymphosarcoma).
Rechecking abnormal values in 30-45 days is advised to account for dynamic changes during disease in an immunocompetent system. Immunologic testing in foals is better interpreted when accompanied by control samples from age-matched and breed-matched healthy foals to account for developmental changes in the immune system.
Immunological testing in horses:
- serum immunoglobulin concentrations (IgG, IgM, IgA);
- pre- and post-vaccination serum tetanus toxoid or pneumococcal antibody titers;
- peripheral blood lymphocyte phenotyping;
- peripheral blood lymphocyte proliferation;
- peripheral blood neutrophil function (oxidative burst activity).