Background Calcium deposits (calcinosis) in Systemic Sclerosis (SSc) are clinically heterogeneous both for site and severity of involvement. Despite often leading to complications such as digital ulcers and driving poor hand function, little attention has been paid to the pathogenesis of calcinosis and the therapeutic options remain limited. The presence of calcinosis in limited cutaneous SSc as well as in the diffuse form suggests that the condition may be associated with vasculopathy rather than fibrosis, however to date, no formal studies have addressed this hypothesis.

Objectives We performed video-capillaroscopy of peri-calcinotic skin and unaffected skin in the same but contra-lateral Region of Interest (ROI), to determine whether we could detect any calcinosis – specific change in the capillaroscopic pattern.

Methods Eighteen calcinotic deposits and contra-lateral ROIs were analysed with an Optilia Digital video-capillaroscopy system equipped with 200x magnification lens. For each calcinotic deposit we captured images in the 4 surrounding quadrants within 3 millimetres of the lesion. Images from each quadrant were captured, indentified and stored and in an electronic database. Analysis of the images was performed by two rheumatologists fully trained in video-capillaroscopy and blinded to the clinical details. Presence of; enlarged capillaries, Giant capillaries, Haemorrhages, Drop-out, disorganisation and capillary ramifications were assessed independently. McNemars tests were employed for statistical analysis.

Results Twelve of the 18 calcinotic deposits were located at the distal phalanx, 3 at the proximal phalanx, 1 at both the middle and proximal phalanx and two at the palmer metacarpal.

Drop out areas were observed in at least 1 quadrant of all 18 calcinotic deposits vs 7 contra-lateral control ROIs (p=0.05). Enlarged capillaries were observed at 17 deposits vs 11 ROIs (p =0.05), giant capillaries, disorganisation and capillary ramifications were observed at 7, 9 and 5 deposits, respectively, while none were observed in any ROIs (P < 0.05 for all). Haemorrhages were observed at 5 deposits and 2 ROIs, (P = 0.05).

Conclusions This pilot study suggests that specific features of severe vasculopathy such as drop out areas, giant capillaries and disorganisation of the vascular array are observable in plain skin video-capillaroscopy and may be specifically associated with calcinotic deposits in SSc. Further studies are warranted both to unravel the role of vasculopathy in the pathogenesis of calcinosis and to determine potential benefit of therapeutic options targeting peripheral vasculopathy.

Disclosure of Interest None Declared