As the coronavirus pandemic is still threatening and killing people all over the world, a group of more than 400 French dermatologists compared notes and noticed that some patients, who were later diagnosed with COVID-19, came to see them with unusual symptoms: redness and swelling of the tip of their fingers or toes, sometimes associated with pain as if they had frostbite (the medical term is acrosyndrome).
Some of the patients had small itchy eczema-like lesions on their extremities (the medical term is dyshydrosis). Those symptoms appeared suddenly without being exposed to cold or any other possible culprit, and they were temporary.
The dermatologists also noticed some patients had reddened patches of skin on their body and sometimes on their face (similar lesions are called urticaria by dermatologists).
The French dermatologists published a note in the French medical journal “La Revue du Praticien,” describing the symptoms and suggesting that the novel lesions could be early symptoms of infection by COVID-19. They suggested that the symptoms could be due to inflammation of the blood vessels (vasculitis).
How can we explain this inflammation of the blood vessels?
In an upcoming May 2020 issue of Clinical Immunology, Wen Zhang and colleagues from the National Clinical Research Center for Dermatologic and Immunologic Disease in Beijing, China talk about a cytokine storm associated with certain COVID-19 infections where in the reaction to the coronavirus entering our body, our immune cells secrete molecules like interleukin 6, interleukin 8, tumor necrosis factor alpha, interferon gamma (all cytokines) that create inflammation in the body.
Sometimes during severe infections, our immune cells secrete too many of those inflammatory cytokines into the blood, which creates a cytokine storm which can create inflammation in our blood vessels (vasculitis). Some of our inflamed blood vessels are inside our body and are not externally observable whereas others are easily seen like the ones in our extremities.
Wen Zhang mentions that small blood vessels in severe COVID-19 patients show vessel wall thickening and obstruction of the vessel’s opening (called lumen) which can explain the swelling, redness, and pain of the tip of fingers mentioned by the French dermatologists.
In fact, a similar rash is seen in Kawasaki disease in children, and in patients with toxic shock, which are caused by cytokines produced in an excessive immune response to infections.
French physicians are wondering whether there is a relationship between the dermatological symptoms observed and the severity of the COVID-19 infection that develops later. More studies are warranted.
As a consequence of their findings, French dermatologists suggest that people complaining of sudden redness, swelling, or pain in the tip of the fingers or toes contact their physician and as a precaution, stay home and self-isolate because, if the fingertip symptoms are early symptoms of COVID-19, patients with these symptoms could be contagious.