Profile of autoantibodies in human diseases.

Testing for autoantibodies has an important place in the clinical immunodiagnostic laboratory. The presence of autoantibodies can aid in the diagnosis or confirmation of AID, as in the case of chronic thyroiditis, which is invariably associated with thyroid antibodies. Conversely the lack of antibody can help exclude the diagnosis of disease. The diagnosis of SLE can virtually be ruled out in patients who do not have ANA. Finding autoantibodies may help in difficult differential diagnosis, such as in those patients with liver disorders. Sometimes the type of autoantibody may be an indicator of prognosis. An example is in those SLE patients who develop anti-DNA antibodies, as mentioned previously. Along the same line, monitoring ANA has been of value in establishing effective treatment in SLE patients, as ANA disappear upon therapy and recur with return of active disease. The detection of autoantibodies may also be used for the identification of other family members of patients with AID who may have a greater risk of developing the disease. Finally, autoantibody detection has provided a tool for basic research which has aided both in classification of disease and increased our understanding of the normal control of immune regulation.