Background Acro-osteolysis and calcinosis are frequent clinical features in Systemic sclerosis (SSc). These manifestations are thought to have a vascular origin but there is still a lack of evidence to objectively support this hypothesis. Ulnar artery occlusion (UAO) is also a specific and frequent vascular feature in systemic sclerosis and Power Doppler Ultrasonography (PDUS) has proven to be a reliable tool to assess the permeability of the ulnar artery.
Objectives The objective of this study is to determine whether calcinosis and acro-osteolysis (AO) are related to vascular features evaluated by PDUS.
Methods A vascular Power Doppler Ultrasonographic evaluation of both hands and bilateral hand X-rays were systematically performed in 43 patients matching the ACR 2013 classification criteria of SSc. PDUS of both hands was performed to evaluate the prevalence of UAO. Finger pulp blood flow (FPBF) of the third and fourth fingers were also assessed and considered pathological if a defect of the doppler signal on a finger pulp was observed. Radiological assessment of calcinosis and acro-osteolysis was performed blinded for the results on PDUS features.
Results 43 patients were consecutively recruited during a 6-month period. The mean age was 56,6 years, 70% of the patients were women, 44,2% had a limited cutaneous SSc, 37,2% had a history of multiple digital ulcers (DUs).
23 patients had a pathological FPBF (53,5%), 22 had a UAO (51,2). Patients with AO on X-rays were more likely to have a pathological FPBF or UAO (respectively p=0,029, Odds Ratio (OR) =4,36; 95% confidence interval (1,112–17,128) and p=0,002; OR=8,67; 95%CI (1,97–38,41)). There was no association between calcinosis on X-rays and pathological FPBF or UAO (p=0,362 and 0,076 respectively). UAO and FPBF were both associated with classical ischemic manifestations of the disease such as multiple DUs history (p=0,002 and p=0,029).
Multivariate logistic regression analysis revealed an independent association between UAO and AO (p=0,003, OR=2,08; 95%CI (1,79–35,74)).
Conclusions A study has recently shown that acro-osteolysis was independently associated with the late nailfold videocapillaroscopic pattern (Morardet et al. Arthirtis Care Research, jul 2015). These results strengthened the link between this radiographic lesion and digital destructive vasculopathy. Our study reveals an association between UAO or FPBF assessed by PDUS and acro-osteolysis. These results suggest once again a vascular etiology to AO and provides new evidence of the link between micro and macro-vascular damages in SSc.
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.
Morardet et al. Late nailfold videocapillaroscopy pattern associated with hand calcinosis and acro-osteolysis in systemic sclerosis. Arthritis Care Res 2015 Jul 20. doi: 10.1002/acr.22672
Acknowledgement The authors gratefully acknowledge all patients and investigators involved in this study. The authors also thank, P. Lescoat, Dr M. Sebillot, M. De Carlan and Pr O. Decaux for their comments.
Disclosure of Interest None declared