To evaluate the relevance of power Doppler ultrasonography (PDUS) as a predictive tool of 1-year digital ulcer (DU) occurrence in systemic sclerosis (SSc).
A total of 55 SSc patients and 19 controls 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 was also assessed and considered as pathologic if a defect of the Doppler signal on a finger pulp was observed. All patients were clinically re-evaluated 6 and 12 months later and new ischemic DU occurrences in the meantime were retrospectively recorded. Patients were also asked to call if new DUs occurred between consultations.
PDUS parameters were normal in all controls. The prevalence of UAO was 36.4% and was bilateral in 70% of the SSc cases. A total of 56.4% of SSc patients had a pathologic FPBF. UAO and pathologic FPBF were associated with a history of multiple DU episodes (odds ratio [OR] 8.98 [95% confidence interval (95% CI) 2.52-32.01], P < 0.001, and OR 4.69 [95% CI 1.30-16.93], P = 0.014, respectively) and the occurrence of new DUs during the followup in the univariable model (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, respectively). The association of UAO and pathologic FPBF in the same patient was a predictive factor of new DUs in the multivariable analysis (P = 0.015).
This study suggests that UAO and pathologic FPBF are associated with a history of multiple DUs and are predictors of new ischemic DUs. These parameters could be used as prognostic factors and considered in further studies evaluating DU treatment strategies.