A review of nail findings associated with COVID‐19 infection

Abstract

According to recent data, up to 20% of patients with COVID-19 have cutaneous manifestations. Nails can also develop abnormalities during and after infection. In this article, we review the nail findings observed in patients with COVID-19.We reviewed the PubMed and Embase databases to identify all articles up to May 2021 that have described nail findings in association with COVID-19.A total of 70 studies were reviewed including 61 studies on chilblain-like lesions, which are one of the most widely identified cutaneous findings associated with the COVID-19 pandemic.Nine studies described specific nail findings (Table 1). Three of these findings [Beau lines, 1 transverse leukonychia, 1,2 and onychomadesis (Figure 1a)] are commonly seen with other systemic disease, including viral infection, and are likely the consequence of high fever and/or severe illness. One finding, paronychia, was seen in association with chilblain-like lesions, 3 and three nail findings (the red half-moon sign 4,5 (Figure 1d), the transverse orange discoloration 6 and the diffuse red-white nail bed discoloration 7 ) are novel and potentially related to the microvascular injury due to COVID-19. Of note, an orange-brownish discoloration of the nail in a transverse pattern, the most similar finding to date, has been described in patients with Kawasaki disease, which shares a similar inflammatory response component to COVID-19.COVID-19's effects on the nail blood vessels were documented by Navarro et al. in 12 pediatric patients with COVID-19-related chilblains, described in Table 1. 8 At dermoscopy of the nail fold and hyponychium, they found a red background with globules, indicative of vascular damage.We also documented dilated and tortuous capillaries at dermoscopy in a patient with transverse leukonychia after COVID-19 infection (Figure 1c).The presence of microvascular abnormalities was confirmed by a capillaroscopy study of the nails of 82 patients, enrolled during hospitalization for , or shortly after discharge. 9 Using nail video capillaroscopy (NVC), the authors observed microvascular abnormalities in all patients, which are described in detail in Table 1. Findings varied between acutely ill and discharged patients, providing visual evidence of a vascular pathogenic component to COVID-19 infection.Chilblain-like lesions are a commonly reported manifestation involving the digits. They are also known as 'COVID toes,' even

Thiamethoxam-Induced Subclinical Onychomadesis

“…Table 1. Causes of onychomadesis described in the literature [1][2][3][4][5][6][7][8][9][10][11][12]…”

Nails and COVID ‐19 – A comprehensive review of clinical findings and treatment

“…Beau's lines may precede onychomadesis, characterized by separation of the nail plate from the nail matrix, with persistent attachment to the nail bed. Onychomadesis is a possible consequence of COVID‐19 27,28 …”

“…Onychomadesis is a possible consequence of COVID-19. 27,28 Another late manifestation of COVID-19 disease is a heterogeneous red-white discoloration of the nail bed with distal onycholysis. 29…”

Red nail bands in conjunction with telogen effluvium as a post‐COVID‐19 phenomenon

“…PNP is characterised by severe stomatitis or lichenoid skin lesions (or both), the presence of neoplasia, demonstration of anti-plakin autoantibodies, and histologic features of acantholysis and/or interface dermatitis. [1][2][3] PNP has two major clinical phenotypes, including blisters and lichenoid eruptions, 3 both of them have characteristic features detected with reflectance confocal microscopy (RCM), and the lichenoid component may be a useful differentiator between PNP and pemphigus vulgaris (PV). We herein presentfor the first time -RCM criteria for PNP in correlation with histopathological features.…”

“…1 Acute telogen effluvium and various nail changes such as Beau's lines, red half-moon nail sign, onychomadesis and distal orange discoloration have been reported in COVID-19 patients in isolation. 2 Herein, we report 4 cases with nail changes showing red bands in the setting of post-COVID-19 telogen effluvium.…”