Background In a recent EUSTAR study, joint synovitis and tendon friction rubs reflecting fibrotic tenosynovitis (fTS) have proven to be independent predictive factors for disease progression in patients with early systemic sclerosis (SSc). Power Doppler Ultrasonography (PDUS) of the hand can detect early asymptomatic joint synovitis or fTS and is a reliable tool to perform a vascular evaluation of the hand, especially to assess ulnar artery involvement.
Objectives The objective of this study is to determine whether joint synovitis, fTS and ulnar artery occlusion (UAO) assessed by PDUS of the hand are associated with visceral manifestations of SSc and can thus be considered as severity markers of the disease.
Methods 47 systemic sclerosis patients matching the 2013 EULAR/ACR classification criteria of SSc were consecutively included in this observational transversal study. Patients were also classified using 2008 LeRoy classification subsets. A bilateral US evaluation of both hands of every patients was performed assessing the presence of active synovitis, fTS or UAO. PDUS features were confronted to the visceral manifestations of the disease assessed by the annual standard investigations: pulmonary function tests (PFTs), thoracic CT-scan, echocardiographic evaluation. A right heart catheterization (RHC) was conducted if pulmonary arterial hypertension (PAH) was suspected based on the results of the previous tests. PDUS of the hand was performed blinded for the results of visceral investigations.
Results A fibrotic TS was present in 17% of the patients. fTS was associated with an interstitial lung disease on CT-scan and a diffuse cutaneous involvement (respectively p=0,023; Odds ratio (OR)=10,06; 95% confidence interval (1,13–89,94) and p=0,018; OR=11,2; 95%CI (1,125–100,31). An active synovitis was present in 14,9% of the patients and was associated with pericarditis on the echocardiographic evaluation (p=0,05; OR=15,6; 95%CI (1,19–204,78)). There was a significant association between PAH on RHC and bilateral UAO on PDUS (p=0,008, OR non available because every patient with PAH had a bilateral UAO).
Conclusions The evaluation of the hand by Power Doppler Ultrasonography in SSc provides new evidence that vascular, joint and tendon involvements reflect visceral manifestations of SSc and therefore constitute severity markers of the disease. These results should be completed by prospective studies to determine whether these PDUS features are also independent predictive factors for disease progression, especially in patients with early 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.
Avouac J et al. Joint and tendon involvement predict disease progression in systemic sclerosis: a EUSTAR prospective study. Ann Rheum Dis. 2016 Jan;75(1):103–9
Acknowledgement The authors gratefully acknowledge all patients and investigators involved in this study. The authors also thank M. De Carlan, Dr M. Sebillot and Pr O. Decaux for their comments.
Disclosure of Interest None declared