Dermatological complications due to post‑COVID‑19 syndrome: A systematic review

Almost 20% of patients affected by COVID-19 develop dermatological symptoms after recovery. This condition is termed as post-COVID-19 syndrome and is characterized by a state of hyperinflammation, as well as deregulations in the humoral response of CD8⁺ T-cells. Since there is no specific treatment for these injuries, the treatment of choice depends on the symptoms; thus, it is essential to provide a description of the type and nature of the injuries presented. In the present study, a systemic review was performed using the PICO strategy in the repositories of PubMed, Google Scholar, Embase and Scopus using the key words 'POST-COVID and skin symptoms'. A total of 44 studies were included in the present systematic review. In these studies, the majority of subjects exhibited non-specific symptoms, commonly referred to as 'skin rash', affecting up to 27.4% of the population. According to the studies, a maximum prevalence of 50% of alopecia was observed among the affected subjects. Additionally, several studies reported the prevalence of other lesions, including pruritus (25%), subcutaneous nodules (12%), dermatitis (9.4%), edema (9%) and pigmentation changes (6%). Dermatological lesions associated with autoimmunity were also identified, with these findings being more pronounced among females and in patients with a history of severe COVID-19. Finally, several studies investigated the presence of autoantibodies, revealing a maximum prevalence of 41% for autoantibodies targeting the epidermis. Specifically, the prevalence was 12.9% for the Wuhan variant, 5.7% for the Alpha variant and 5% for the Delta variant. Although mostly benign, post-COVID-19 syndrome produces marked dermatological alterations for hair health, mainly among females. This, together with the development of lesions with an autoimmune component, constitutes an emerging therapeutic need.