Scleroderma Comprehensive Plus Profile (RDL)

Scleroderma Profile Interpretation

• Anti-Nuclear Abs: Positive in more than 95% of patients with Scleroderma.

• Anti-Centromere Abs are found in more than 95% of patients with Scleroderma.

• Anti-Centromere Abs are found in 46% of patients with limited Systemic Sclerosis and 11% in diffuse Systemic Sclerosis, as well as 12% of patients with primary biliary cirrhosis, and are rarely present in normal individuals. The antibodies recognize primarily Centromere B, a major centromere protein, and are associated with CREST Syndrome.

• Anti-Scl 70 are highly specific for scleroderma. They are present in about 20% of diffuse SSc, and 10% of limited SSc. The antibodies are associated with digital ulcers, Raynaulds, pulmonary fibrosis, renal crises, and heart disease. EIA testing can yield false positive results, therefore, all EIA positive tests are confirmed with immunodiffusion.

• Anti-U1 RNP abs can be found in 2-14% of limited SSc and 5% of diffuse SSc, They are associated with isolated pulmonary arterial hypertension, arthritis, and esophageal dysfunction.

• Anti-TH/TO abs can be found in 2-6% of patients with limited SSc and are rarely found in diffuse SSc. They are associated with isolated pulmonary arterial hypertension, arthritis, and esophageal dysfunction.

• Anti-Fibrillarin (U3 RNP) are highly specific for diffuse SSc with a sensitivity of 4-10%. They are associated with isolated arterial hypertension, myositis, and cardiac manifestations of SSc.

• Anti-RNA Polymerase III are useful in the diagnosis of SSc and for the identification of patients at risk for developing renal crisis, progressive skin thickening and cancer. The prevalence of IgG RNAP III antibodies is 20-30% in diffuse SSc and 9% in limited SSc.