Table 1:

Autoantibodies associated with systemic sclerosis and their clinical correlates

	Cutaneous subtype	Clinical correlates
Anti-centromere	Limited cutaneous systemic sclerosis	Pulmonary arterial hypertension
Anti-topoisomerase 1 (anti-ScI 70)*	Diffuse cutaneous systemic sclerosis	Progressive interstitial lung disease
Anti-RNA polymerase 3	Diffuse cutaneous systemic sclerosis	Renal crisis and malignancy
Anti-U1 ribonucleoprotein (anti-ribonucleoprotein)	Limited cutaneous systemic sclerosis	Mixed connective tissue disease
Anti-U3 ribonucleoprotein (anti-fibrillarin)	Diffuse cutaneous systemic sclerosis	Pulmonary arterial hypertension and myositis
Anti-Pm-Scl	Limited cutaneous systemic sclerosis	Myositis
Anti-Th/To	Limited cutaneous systemic sclerosis	Interstitial lung disease and pulmonary arterial hypertension

Testing for systemic sclerosis-associated auto-antibodies is recommended early in the evaluation for systemic sclerosis because it can help establish a systemic sclerosis diagnosis and inform risk-stratification strategies. Patients will seldomly produce more than one systemic sclerosis-related auto-antibody concurrently.

^*Immunodiffusion is the preferred method for detecting anti-topoisomerase 1 antibodies, given that multibead assays are associated with high false-positive rates.