Dermatologists warn: Covid toes could become a constant companion

Doctors in the USA, Italy and Spain were the first to observe the phenomenon in children and adolescents in early summer: They developed a reddish-purple or bluish discoloration on their feet that was reminiscent of chilblains. After that, blisters appeared and later blackish incrustations. The often painful symptoms usually healed completely within two weeks. Often the patients had no other complaints – just those toes that looked like they had been exposed to the freezing cold for a long time. But it was spring.

Then a team led by Isabel Colmenero from the University Children’s Hospital in Madrid succeeded in proving that these skin symptoms represent one of the numerous Sars-CoV-2 symptoms. They were able to detect an antigen of the Sars-CoV-2 spike protein in seven skin samples from affected children between the ages of eleven and 17. The viruses were found in the inner lining of the smallest blood vessels.

Stubborn inflammation can persist for months

Spanish dermatologists were also the ones who also examined the phenomenon in adult Covid patients in a study with 375 participants. “Covid toes” are among the rare side effects of the infection. However, the inflammation can be particularly persistent. Individual patients suffer from it for up to six months after Covid-19.

Otherwise, there were contradicting statements about skin symptoms and Covid-19 in early summer. Since the children observed were either symptom-free or only very mildly ill, some doctors said that the pseudo-chilblains were an early sign, while others said the inflammation would appear late. Still others questioned the direct connection to coronavirus infection. We know more now.

The American Academy of Dermatology has launched an international registry for skin problems related to Covid-19. Half of the entries from dermatologists around the world concern Covid toes.

Dermatologists warn of underestimated long-term consequences

Esther Freeman, a dermatologist at Harvard University and the registry’s head of research, fears that some Covid-19 patients may retain skin problems as a long-term consequence of the disease. Including many adults with Covid toes. The dermatology professor concludes from an evaluation of 1000 patient data in the registry. She presented the study results at the end of October at the online congress of the European Academy of Dermatology and Venereology. They are still unpublished.

The phenomenon of “Covid toes” rarely occurred in Germany, but it is not unknown to dermatologists and paediatricians. The dermatology professor Cord Sunderkötter from the University of Halle an der Saale took a closer look at it.

Here is a summary of his explanations on the website of the German Dermatological Society:

The reddened swellings as well as clear or pus-filled blisters characterize a frostbite-like skin disease. This dermatosis usually only develops in the later course of Covid-19 and, in contrast to real chilblains (Perniones), also in warm temperatures instead of just in damp and cold conditions. “Covid toes” typically affect young and less seriously ill patients.

Covid toes – a mixture of inflammation, swelling, and vascular occlusion

“Covid toes” show a mixed picture of inflammation around the vascular wall with swelling of the vascular cells and sometimes thrombotic occlusions. This leads to itching or pain or both or no abnormal sensations in those affected. The shares are each a quarter.

Doctors observe the deterioration and destruction of tissue (ischemic necrosis) on the feet with Covid-19 less often than the “Covid toes”. According to Sunderkötter, necroses are increasingly caused by inflammation in the vascular wall or embolisms in the context of severe coagulation disorders in Covid-19. Patients with a Sars-CoV-2 infection often develop symptoms in other organs that indicate thrombosis or inflammation in the large, medium-sized or small vessels.

In countries with many Covid-19 patients, experience shows that the symptoms associated with Covid toes often subsided after two to four weeks without special treatment.

There is no specific treatment anyway. Doctors can only treat symptomatically: with painkillers, antipruritic creams, or, in the case of severe inflammation, with cortisone ointment for a short time.