Autoimmune Dermatological Symptoms after Covid-19 Infection

It has been estimated that 20% of patients who recover from Covid-19 develop dermatological issues.

A literature review was recently published of studies accessed across several peer-reviewed research platforms using the keywords “post-Covid and skin manifestations.” A total of 44 studies published between January 2020 and January 2024 were analyzed in the review, and it was determined that up to 50% of subjects were observed to develop alopecia post-Covid infection. The average follow-up period following Covid-19 diagnosis for the studies included in the review was 7 months, with a minimum follow-up period of 6 weeks and a maximum of 12 months.

Several studies addressed the prevalence of autoantibodies targeting the epidermis specifically, and dermatological lesions associated with autoimmunity were identified and found to be more pronounced among females and those who had severe Covid-19. While the majority of cutaneous conditions were non-autoimmune in nature, six studies covered cases of dermatitis with a significant inflammatory component, as well as worsening or reactivation of autoimmune-related conditions like dermatomyositis and psoriasis.

“In two studies, antibodies against the epidermis were found in up to 41% of the affected subjects.”

Overall, there were two possible pathophysiological mechanisms involved in these dermatological symptoms outlined in the studies included in this review: hyperinflammation and immune dysregulation. One possibility cited the cytotoxic potential of the coronavirus interacting with ACE2 receptors on the skin, causing endothelial dysfunction characterized by hyperinflammation, vasculitis, as well as the development of skin lesions. “Persistence of this inflammatory state would increase the production of specific interleukins (IL), such as IL-6 and IL-4. The former has been linked to the loss of immune regulation that normally maintains hair follicles in an immune-privileged state, thereby ensuring their normal growth.” Interleukins can modify the cellular microenvironment at the base of the hair bulb and can trigger hair fallout. Other studies cited anti-epidermal antibodies and mitochondrial dysfunction in epidermal cells. These and other mechanisms have been previously identified as contributors to dermatological symptoms from Covid-19 as well as other viral infections.

The development of autoimmunity and the reactivation of autoimmune symptoms show that Covid-19 can trigger T-lymphocytes to create an autoimmune environment, especially in females.

These cases confirm previous findings that patients have the ability to develop autoantibodies following infection, regardless of whether they have a history of autoimmunity.

Citation:

Cayón Figueroa, B. A., et al. (2024). Dermatological complications due to post‑COVID‑19 syndrome: A systematic review. Medicine international, 5(1), 9. https://doi.org/10.3892/mi.2024.208