A Window into the Vascular Endothelium in Covid-19: Nails

Endothelial damage is associated with acute and long-term coronavirus disease 2019 (COVID-19) complications. Proximal nailfold capillaries and nail beds give important clues to microvascular changes associated with endothelial dysfunction.

We aimed to use dermoscopy to examine the proximal nailfold capillaries and nail bed of COVID-19 patients and identify microvascular changes.

A prospective study was designed to evaluate the dermoscopic features of proximal nail fold capillaries and nail bed in mild-to-moderate COVID-19 patients and healthy controls between June 2022 and December 2023. The patients underwent their initial dermoscopic examination two weeks after the onset of symptoms, followed by a follow-up evaluation 10-14 months later.

The study included 46 patients with mild-to-moderate COVID-19 and 62 healthy controls. The presence of avascular areas (P <0.001), meandering capillaries (P = 0.016), microhemorrhages (P = 0.007), and enlarged capillaries (P = 0.009) in the proximal nail fold was significantly higher in COVID-19 patients than in healthy controls. The capillary architecture was disorganized (P = 0.002) and density reduced (P <0.001) in COVID-19 patients compared to healthy controls. In the follow-up examination, microvascular changes were observed to have regressed.

Proximal nailfold dermoscopy is an effective, low-cost, easily accessible method that enables observation of microvascular changes in COVID-19 patients.