Assessing the role for nailfold videocapillaroscopy in interstitial lung disease classfication: a systematic review and meta-analysis.

objectivesThe nailfold videocapillaroscopy (NVC) has been known to assist with interstitial lung disease (ILD) classification. However, evidence on its diagnostic efficacy is limited, particularly in some connective tissue disease-related interstitial lung diseases (CTD-ILD), and in interstitial pneumonia with autoimmune features (IPAF). This study aimed to address this limitation by conducting a meta-analysis on the efficacy of the NVC in ILD subgroups of CTD-ILD, IPAF and idiopathic pulmonary fibrosis (IPF).

methodsMEDLINE, EMBASE, CENTRAL were screened from inception to December 2020 according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies that report prevalence of nailfold abnormalities (NVC+) in CTD-ILD, IPAF and IPF cohorts were included. Data were presented as prevalence ratio (PR) with 95% CI using a random-effects model. Quality of evidence was assessed using GRADE criteria.

resultsTwenty-one studies were eligible. Prevalence of NVC+ was highest in CTD-ILD; PR (95 CI%) 80.4% (74.3%, 85.3%), followed by IPAF; 27.4% (10.9%, 53.7%), and IPF; 13.8% (5.7%, 29.9%). Late scleroderma pattern was the most prevalent nailfold pattern; 40.4% (28.1%, 54.1%) in our CTD-ILD cohort. Quality of evidence was low for CTD-ILD, IPAF and IPF cohorts, moderate for the late scleroderma pattern cohort.

conclusionNVC can increase the diagnostic accuracy of ILD when used in a multi-disciplinary setting, and appears to have greatest utility in CTD-ILD, followed by IPAF and IPF. The Late Scleroderma Pattern was the most frequent nailfold capillary pattern in SSc-ILD. Future research will allow for greater understanding of the prognostic value of the NVC in ILD.