Evaluating Nailfold Capillaroscopy as a Diagnostic Tool in EGPA with Pulmonary Involvement

Introduction: Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) includes granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). These systemic disorders involve necrotizing inflammation of small- to medium-sized blood vessels. While nailfold videocapillaroscopy (NVC) is a proven, non-invasive technique for assessing microvascular changes in conditions like systemic sclerosis, its application in AAV, particularly EGPA, remains underexplored. NVC could potentially aid in diagnosing EGPA, especially given the current limitations of classification criteria, which often hinder precise diagnosis of these vasculitides. Objects: This study aims to evaluate the potential role of nailfold videocapillaroscopy (NVC) in the diagnosis of EGPA by assessing the presence of microvascular abnormalities in patients. The goal is to identify characteristic capillaroscopic patterns that may assist in the diagnosis and understanding of the disease. Methods: A cohort of 34 individuals diagnosed with eosinophilic granulomatosis with polyangiitis (EGPA)—comprising 23 females and 11 males, aged between 54 and 75 years—and an equal number of healthy controls matched for age and sex were selected from the patient records between October 2023 and May 2025. All participants provided informed consent and met predefined inclusion (18 years old or more; diagnosis of EGPA [2022 and 2012 criteria] (1,2). Signed written informed consent) and exclusion criteria (minor age, presence of hypoxia and comorbidities). Nailfold videocapillaroscopy (NVC) was performed on both groups to evaluate various structural features of the microvasculature, with an additional calculation of average capillary density [Figure 1] (3). Results: The analysis revealed distinctive capillaroscopic changes in the EGPA group, such as a reduction in capillary density observed in 40 % of patients, the presence of new vessel formation in 70%, capillary rolling phenomena in all patients (100%), pericapillary stippling seen in 72%, and inverted capillary tips in 64%. Notably, these capillaroscopic alterations (neoangiogenesis, capillary rolling, stippling, and inverted tips; figure 1) were more prominently present in a statistically significant manner in patients with EGPA compared to healthy subjects (p-values< 0.001, for all). However, there was no significant correlation between the pulmonary function tests (FEV1, FVC, DLCO) and the presence of capillaroscopy alterations in EGPA patients (p=0.06). Conclusions: Our findings indicate that certain capillaroscopic abnormalities—specifically neoangiogenesis, capillary rolling, stippling, and inverted capillary tips—are more frequently observed in individuals with EGPA relative to healthy individuals. Ongoing research endeavors aim to evaluate the potential utility of NVC as a non-invasive diagnostic tool and to explore its relationship with the clinical presentation and disease activity in EGPA patients.