The anticentromere antibody (ACA) is an autoantibody that is produced by the immune system and targets the body’s own tissues, specifically a component of the chromosomes called the centromere. The variant of scleroderma, the CREST syndrome, is characterized by calcinosis, Raynaud’s phenomenon, esophageal dysfunction, sclerodactyly, and telangiectasia. Characteristically, ACAs appear in about 90% of these patients. This antibody is detected by using Hep-2 cells in various stages of cell division. The centromere region of the cell chromosomes will stain if an ACA is present.

• Negative for ACA by IFA or ELISA. If positive by IFA, the serum is titered.

1. Collect a 7-mL blood serum sample in a red-topped tube. Observe standard precautions.

2. Label the specimen with the patient’s name, date, and test(s) ordered and place in a biohazard bag for transport to the laboratory.

Positive results are associated with the CREST syndrome in scleroderma.

See Antinuclear Antibody (ANA) Test.