Raynaud's phenomenon and digital ulceration in systemic sclerosis.

Systemic sclerosis (SSc) is a vascular disease. Immune-mediated endothelial injury leading to vasculopathy characterised by a progressive obliterative microangiopathy is a key aetiopathogenic driver of SSc. This typically manifests clinically as Raynaud's phenomenon (RP), which occurs in virtually all individuals with SSc and digital ulcers (DU), which develop in around half of patients at some stage in the disease course. The term RP encompasses a constellation of clinical features associated with digital vasospasm, typically in response to cold exposure. People with SSc-DU typically report more severe RP symptoms but it is an over-simplification to suggest that DU are simply a consequence of profound RP. The level of ischaemic tissue injury required to cause DU requires more protracted tissue hypoxia and there is a large body of work linking SSc-DU disease with progression of the obliterative microangiopathy and irreversible capillary loss typical of established SSc. The present chapter shall discuss the burden, aetiopathogenesis, assessment and management of SSc-RP and SSc-DU. We shall highlight practical considerations for the assessment and management of these digital vascular complications in routine clinical practice. The complexity of SSc-related digital vasculopathy is illustrated through examples from the clinic setting. The management of these complications shall focus on recently published clinical guidelines, highlighting nuances of management and the therapeutic rationale underpinning the use of unlicensed therapies for which the evidence base is sometimes scant.