Antibodies directed against "self" components are believed to be responsible for the pathogenesis of many diseases. Some show widespread systemic involvement (Table 3-6), whereas others are confined to a specific organ system (Table 3-7).

* See also Chapter 4 - Immunohematology and Blood Banking

• Many drugs may cause false-positive results in certain autoantibody tests (Table 3-8).

• Signs and symptoms of the disorder for which each test is pathognomonic or for which the test provides confirming data (see Tables 3-6 and 3-7)
• Monitoring of response to treatment for autoimmune disorders

Nursing Care Before the Procedure

Client preparation is the same as that for any study involving the collection of a peripheral blood sample (see Appendix I).

• Food and fluids are not restricted, except for the cryoglobulin test, which requires a 4-hour fast from food.

The procedure is the same for all autoantibody tests, except cryoglobulins. A venipuncture is performed and the sample collected in a red-topped tube. For cryoglobulins, the sample is collected in a prewarmed red-topped tube. The sample must be handled gently to avoid hemolysis and sent promptly to the laboratory.

Nursing Care After the Procedure

Care and assessment after the procedure are the same as for any study involving the collection of a peripheral blood sample. Resume food withheld before the test.

• Complications and precautions: Note and report the presence of cell-specific or tissue-specific antibodies in relation to a suspected disease and the presenting signs and symptoms.