Psoriasis is a chronic inflammatory skin condition. COVID-19, caused by the SARS-CoV-2 virus, primarily affects the respiratory system. Recent observations suggest a connection between COVID-19 infection and the onset or worsening of psoriasis. This article explores the relationship, examining current evidence and underlying biological mechanisms.
Understanding Psoriasis
Psoriasis is an autoimmune disease where the immune system mistakenly attacks healthy skin cells. This accelerates skin cell growth, causing cells to build up rapidly on the skin’s surface, forming thick, scaly plaques. While the exact cause remains unknown, it involves genetic predispositions and environmental factors. Common types include plaque psoriasis, which accounts for most cases, and guttate psoriasis, often triggered by infections.
The condition is not contagious. It can manifest on various body parts, including elbows, knees, scalp, face, and nails. Although there is no cure, various treatments can help manage symptoms and improve quality of life.
Evidence of a Link
Numerous observational studies and case reports suggest a temporal association between COVID-19 and the development or exacerbation of psoriasis. New-onset psoriasis has been reported following SARS-CoV-2 infection, as have flare-ups or worsening symptoms in people with pre-existing psoriasis.
Different types of psoriasis have been observed, including plaque psoriasis (the most common form) and guttate psoriasis (often linked to infections). A matched cohort study in the UK found SARS-CoV-2 infection was associated with an increased incidence of immune-mediated inflammatory diseases, with psoriasis being approximately 23% more likely to occur in infected patients compared to uninfected ones. Research is ongoing to fully understand the nature and strength of this connection.
Reports also link COVID-19 vaccination to new-onset or exacerbated psoriasis, with plaque psoriasis being the most frequently reported type. However, direct evidence conclusively linking vaccination to psoriasis development is lacking. The overall benefit-risk profile of COVID-19 vaccination affirms that vaccination should continue.
Mechanisms Behind the Connection
Biological hypotheses explaining how COVID-19 might influence psoriasis center on the immune system’s response to the viral infection. SARS-CoV-2 can induce systemic inflammation, a generalized inflammatory response throughout the body. This inflammation can trigger or worsen autoimmune conditions like psoriasis.
Severe COVID-19 cases are often associated with a “cytokine storm,” an excessive and uncontrolled release of pro-inflammatory proteins called cytokines. These cytokines, such as TNF-α, IL-17, and IL-23, are also involved in psoriasis development, suggesting an overactive immune response during COVID-19 could fuel psoriatic flares.
Another mechanism is molecular mimicry, where viral antigens resemble self-proteins. The immune system might mistakenly attack similar healthy host tissues, leading to an autoimmune response. Additionally, the stress response associated with severe illness and the psychological impact of the pandemic are potential triggers for psoriasis flare-ups.
Steps for Management
Individuals who suspect a link between their COVID-19 infection and psoriasis symptoms should consult a healthcare professional. A dermatologist or primary care physician can provide a diagnosis and develop a management plan. This includes assessing new-onset symptoms or changes in existing psoriasis patterns.
Treatment for psoriasis linked to COVID-19 follows standard protocols. These may involve topical creams to reduce inflammation and scaling, phototherapy using ultraviolet light, or systemic medications for more widespread or severe cases. Maintaining overall health through balanced nutrition and stress reduction techniques can also contribute to symptom management. Open communication with healthcare providers about symptoms and medical history ensures personalized care.