Absence of Scleroderma pattern at nail fold capillaroscopy valuable in the exclusion of Scleroderma in unselected patients with Raynaud's Phenomenon

Background: To report the predictive value of nail-fold capillaroscopy (NFC) patterns of vasculopathy for systemic sclerosis (Scleroderma; SSc) in an unselected cohort of patients with Raynaud's phenomenon (RP). Methods: Patients referred to a tertiary SSc clinic with RP were evaluated by light/video-NFC. Clinical diagnosis, details and serology were recorded. Primary RP was defined as RP with no features of connective tissue disease (CTD)/antibody. NFC patterns were determined: normal, non-specific, 'early', 'active' or 'late' SSc patterns. Fulfilment of the VEDOSS or 2013 ACR/EULAR criteria for SSc was determined following NFC assessment. Results: Three hundred forty-seven patients were referred: mean (SD) age 47 (15.2) years. On clinical review, 54 (16 %) did not have RP, 69 (20 %) had primary RP, 52 (15 %) had SSc and 172 (50 %) had secondary RP. NFC SSc pattern was detected in 80 (23 %) patients; 37/52 with SSc, 30/172 with secondary RP, 9/69 with primary RP and 4/54 with no RP. For identifying patients who met either the VEDOSS or 2013 ACR/EULAR criteria for SSc, detection of a SSc NFC pattern had a sensitivity of 71 %, specificity 95 %, positive predictive value 84 % and negative predictive value 90 %. Conclusions: The absence of SSc NFC pattern in patients with RP or suspected CTD is very valuable in the exclusion of SSc.