Article Text
Abstract
Background The consequences of the macrovascular disease on ischaemic digital ulcers (DUs) onccurence are still to be determined in systemic sclerosis (SSc) patients and power doppler ultrasonography (PDUS) is a simple and non-invasive efficient tool to evaluate ulnar artery and fingers pulp blood-flow (FPBF).
Objectives Our aim was to evaluate in a longitudinal study the relevance of PDUS as a predictive tool of new ischaemic DUs in a cohort of unselected SSc patients.
Methods 55 SSc unselected patients fulfilling the 2013 EULAR classification criteria of SSc underwent PDUS of both hands to evaluate the prevalence of ulnar artery occlusion (UAO) at baseline. Finger pulp blood flow (FPBF) of the third and fourth fingers were also assessed and considered as pathological if a defect of doppler signal on a finger pulp was observed. All patients were clinically re-evaluated 6 and 12 months later and new ischaemic DUs occurrence in the meantime was then retrospectively recorded. Patients were also asked to phone if new DUs occurred between the consultations. The main outcome measure was the first new ischaemic DU occurring after PDUS evaluation, defined as a new loss of epidermis with dermis exposure appearing on a finger pulp during follow-up and unoticed at the time of PDUS evaluation. We did not take into account traumatic and calcinosis related DUs.
Results The mean age was 57,6 years, 76.4% of the patients were women, 64.6% had a limited cutaneous SSc, 34.2% had a history of multiple episodes of DUs.
The prevalence of UAO was 36.3% and was bilateral in 70% of the SSc cases. 56.4% of SSc patients had a pathological FPBF.
UAO and pathological FPBF were both associated with a history of multiple DU episodes (OR=8.98; 95%CI (2.52–32.01); p<0.001 and OR=4.69; 95%CI (1.30–16.93); p=0.014) and with the occurrence of new ischaemic DUs during the follow-up (OR=8.73; 95%CI (2.00–38.16); p=0.005 and OR=12.65; 95%CI (1.50–106.77); p=0.005).
Multivariate analysis revealed an independent association between PDUS parameters and a history of multiple DU episodes at baseline (p<0.05).
Kappa coefficients of inter-rater agreement were 0.94 for the presence of pathological FPBF and 0.97 for the presence of UAO on PDUS images. Kappa coefficients of intra-rater agreement were 0.90 for the presence of pathological FPBF and 0.93 for the presence of UAO.
Conclusions UAO and pathological FPBF are associated with a history of multiple DU episodes and are predictors of new ischaemic DUs in SSc patients. These parameters could therefore be used as prognostic factors and considered in further studies evaluating DUs treatment strategies.
Frerix M et al. Ulnar artery occlusion is predictive of digital ulcers in SSc: a duplex sonography study. Rheumatology. 2012 Apr;51(4):735–42.
Park JH et al. Ulnar artery vasculopathy in systemic sclerosis. Rheumatol Int. 2009 Jul;29(9):1081–6.
Acknowledgement The authors gratefully acknowledge all patients and investigators involved in this study, Pr E. Hachulla for his advice, P. Lescoat, Dr M. Sebillot and J.D. Albert for their comments.
Disclosure of Interest None declared