Purpose: Nailfold videocapillaroscopy (NVC) identifies the microvascular hallmarks of systemic sclerosis (SSc) and vascular endothelial growth factor (VEGF) and may play a pivotal role in the associated vasculopathy. The aim of the present study was to compare NVC alterations with clinical subsets, internal organ involvement, and serum VEGF levels in a cohort of selected SSc cases.
Methods: We studied 44 patients with SSc who were evaluated within 3 months from enrollment by NVC, skin score, severity index, pulmonary function tests, carbon monoxide diffusing capacity (DLCO), echocardiography, pulmonary high-resolution computed tomography (HRCT), gastroesophageal (GE) endoscopy or manometry or X-ray, and serum autoantibodies. Serum VEGF-A levels were determined by ELISA in 72 SSc patients and 31 healthy controls.
Results: Giant capillaries were inversely correlated with age (p = 0.034, r = -0.34) and to the extent of reticular pattern at HRCT (p = 0.04, r = -0.5). Avascular areas were directly correlated with capillaroscopy skin ulcer risk index (CSURI) (p = 0.006, r = +0.4) and severity index (p = 0.004, r = +0.5). The mean capillary density was directly correlated to the ulcer number (p = 0.02, r = +0.4) and to DLCO/alveolar volume (p = 0.02, r = +0.4) and inversely correlated with severity index (p = 0.01, r = -0.4) and skin score (p = 0.02, r = -0.4). Serum VEGF levels were higher in the SSc population vs controls (p = 0.03) and inversely correlated with DLCO (p = 0.01, r =-0.4) and directly with ground-glass and reticular pattern at HRCT (p = 0.04, r = +0.4 for both).
Conclusions: Our data suggest the importance of NVC not only for the diagnosis, but also for the global evaluation of SSc patients. Of note, serum VEGF levels may act as a biomarker of interstitial lung involvement.
Keywords: Autoimmunity; Biomarkers; Endothelium; Personalized medicine; Systemic sclerosis.