Study Supports Link Between COVID-19 and "COVID Toes"

There's considerable controversy over whether "COVID toes"—red sores or lesions on the feet and hands in children and young adults—are truly caused by COVID-19. A new study published in the British Journal of Dermatology provides evidence in support of the link.

Chilblains ("COVID toes") are being seen with increasing frequency in children and young adults during the COVID‐19 pandemic. Detailed histopathological descriptions of COVID‐19 chilblains have not been reported, and causality of SARS‐CoV‐2 has not been established yet.

In most cases, affected individuals test negative with traditional COVID-19 tests involving throat swabs and measurements of circulating antibodies, but this study's investigators found that the SARS-CoV-2 virus that causes COVID-19 was present in skin biopsies in children with symptoms of COVID toes, despite negative results from traditional tests.

Histopathology showed variable degrees of lymphocytic vasculitis ranging from endothelial swelling and endothelialitis to fibrinoid necrosis and thrombosis.

Analyses detected the virus in skin's blood vessel endothelial cells, as well as in the sweat glands. Electron microscopy in one biopsy also found evidence of viral particles within endothelial cells.

"Our findings support a causal relation of SARS-CoV-2 with COVID toes. Endothelial damage induced by the virus could be the key mechanism causing these lesions," said lead author Isabel Colmenero, MD, of Hospital Infantil Universitario Niño Jesús, in Spain. "Furthermore, vascular damage could also explain some clinical features seen in patients with severe COVID-19."

Although the clinical and histopathological features were similar to other forms of chilblains, the presence of viral particles in the endothelium and the histological evidence of vascular damage, support a causal relation of the lesions with SARS‐CoV‐2. Endothelial damage induced by the virus could be the key mechanism in the pathogenesis of COVID‐19 chilblains and perhaps also in a group of patients severely affected by COVID‐19 presenting with features of microangiopathic damage.

For more details click on the link: https://doi.org/10.1111/bjd.19327