Introduction. We investigated early Systemic Sclerosis (SSc) (i.e. Raynaud’s phenomenon with SSc marker autoantibodies and/or typical capillaroscopic findings and no manifestations other than puffy fingers or arthritis) versus Undifferentiated Connective Tissue Disease (UCTD) to identify predictors of short-term disease evolution.
Methods. Thirty-nine early SSc and 37 UCTD patients were investigated. At baseline, all patients underwent clinical evaluation, B-mode echocardiography, lung function tests, and esophageal manometry to detect preclinical alterations of internal organs, and were re-assessed every year. Twenty-one early SSc and 24 UCTD patients, and 25 controls were also investigated for serum endothelial, T-cell and fibroblast activation markers.
Results. At baseline, 48.7% of early SSc and 37.8% of UCTD patients had at least one preclinical functional alteration (p > 0.05). Ninety-two percent of early SSc patients developed manifestations consistent with definite SSc (i.e. skin sclerosis, digital ulcers/scars, 2 or more teleangectasias, clinically visible nailfold capillaries, cutaneous calcinosis, X-ray bibasilar lung fibrosis, X-ray esophageal dysmotility, ECG signs of myocardial fibrosis, laboratory signs of renal crisis) within 5 years versus 17.1% of UCTD patients (X 2 =12.26; p=0.0005). Avascular areas (HR=4.39; 95% CI=1.18–16.3; p=0.02), increased levels of soluble IL-2 receptor alpha (HR=4.39; 95% CI=1.03– 18.6; p=0.03), and of procollagen III aminopropeptide predicted disease evolution (HR=4.55; 95% CI=1.18–17; p=0.04).
Conclusion. Most early SSc but only a few UCTD patients progress to definite SSc within a shortterm follow-up. Measurement of circulating markers of T-cell and fibroblast activation might serve to identify early SSc patients who are more likely to develop features of definite SSc.