Nailfold capillaroscopy and organ involvement in systemic sclerosis: a systematic review

Systemic sclerosis (SSc) is connective tissue disease characterised by early microvascular damage and tissue fibrosis. Nailfold videocapillaroscopy (NVC) enables direct assessment of the microangiopathy and classification into "scleroderma patterns", offering potential prognostic value. This systematic review aims to analyse the most updated evidence linking NVC findings with organ-specific involvement in SSc. Uniquely, only longitudinal studies, with centralised reading using the European Alliance of Associations for Rheumatology (EULAR) Study Group on Microcirculation in Rheumatic Diseases consensus framework for nailfold capillaroscopy reporting, and published in the last 10 years were selected. Risk-of-bias assessment was assessed by 3 reviewers using the "QUality In Prognosis Studies" (QUIPS) risk-of-bias tool. In total, 14 manuscripts with low to moderate risk of bias were selected and critically analysed. Reduced capillary density (<7 capillaries/mm) and "Active/Late" scleroderma patterns, consistently predicted disease progression. Low capillary density and both "Active" and "Late" scleroderma patterns were strongly associated with more severe skin fibrosis, digital ulcers and calcinosis, pulmonary (arterial) hypertension and interstitial lung disease. A lowered capillary density further predicted major cardiovascular events and gastrointestinal dysmotility, and linked with subclinical renal vasculopathy. In Early SSc, "Active" or "Late" patterns increased the probability of progression to definite SSc. Finally, reduced capillary density reflects a globally more severe phenotype with worse prognosis. Integrating NVC into routine assessment may enable earlier identification of high-risk patients and promote timely intervention to prevent irreversible organ damage.