CORRELATION OF A QUANTITATIVE VIDEOCAPILLAROSCOPIC SCORE WITH THE DEVELOPMENT OF DIGITAL SKIN ULCERS IN SCLERODERMA PATIENTS

Background: Systemic Sclerosis (SSc) is an autoimmune disease characterized by fibrosis of the skin and visceral organs. SSc microangiopathy is early detectable in the course of the disease by nailfold videocapillaroscopy (NVC), a non-invasive technique with a high diagnostic value.Objectives: Aim of our study is to evaluate the feasibility of a novel, quantitative capillaroscopic score and its correlation with digital skin ulcers, which frequently complicate SSc microangiopathy.Methods: Two operators, in a blind manner, without knowledge of the patient's clinical history, retrospectively analyzed the NVC of 76 SSc patients (9 males, 67 females, mean age 56,3±13,3 years, mean disease duration 79±65 months, at the time of NVC), using an image analyze software (Videocap; DS MediGroup, Milan, Italy).The analysis of every available NVC image (200x) included: total number of capillaries in the distal row (N), maximum diameter (D) and number of giant capillaries (M), M/N ratio and percentage of M, micro-haemorrhages and tortuosity (counted as presence or absence). All parameters were strictly defined to reduce the inter-operator variability.Results: 22/76 SSc patients experienced digital ulcers within three months after the NVC examination. The N, D, M/N, and percentage of M significantly correlated with the appearance of ischemic ulcers. A multiple regression analysis showed a statistically significant correlation for N, D and M/N (with a coefficient of -0.634, 0.406 and 0.630, respectively), while sensitivity and specificity of these parameters were unsatisfactory. A capillaroscopic score, according to the formula DM/N2, showed a high specificity and sensibility (88.9% and 86.4% respectively, area under ROC curve 0.92) to predict the appearance of digital ulcers (mean score 5.85±12.3SD in the whole SSc population, 1.83±1.42SD in patients without ulcers, 15.72±19.74 SD in patients with ulcers; p<0.0001).Conclusion: This capillaroscopic score may represent a feasible and simple tool in SSc patients' assessment. The routinely use of this parameter might permit to recognize and to preventively treat SSc patients at high risk to develop digital ulcers.