Psoriatic arthritis is a chronic inflammatory condition that affects both the joints and the skin. This autoimmune disease is closely linked to psoriasis, a common skin condition, with skin symptoms often appearing before joint involvement. Understanding how psoriatic arthritis manifests on the skin is important for recognizing potential signs of the condition. This article details the diverse skin presentations associated with psoriatic arthritis.
Common Skin Lesions
Plaque psoriasis is the most frequently observed skin manifestation. It presents as raised, red patches, or plaques, typically covered with silvery-white, dry scales. These patches usually have well-defined edges, separating affected skin from healthy areas.
These lesions commonly appear on extensor surfaces like elbows and knees, and also on the lower back and buttocks. They can cause itching, burning, or soreness. The Koebner phenomenon can also occur, where new lesions develop at sites of skin injury.
Nail and Scalp Involvement
Psoriatic arthritis frequently impacts the nails and scalp. Nail psoriasis is common, affecting up to 80-90% of individuals. Signs include pitting (small depressions on the nail surface) and onycholysis (nail separation from the nail bed).
Nails may also show discoloration, such as yellow-brown “oil drop” or salmon patches, along with thickening, crumbling, and ridging. On the scalp, psoriasis manifests as thick, silvery scales, redness, and dryness. This can extend to the forehead, neck, and behind the ears, causing itching and temporary hair loss.
Other Skin Manifestations
Beyond plaque psoriasis, other skin manifestations can occur. Inverse psoriasis appears in skin folds like the armpits, groin, under the breasts, and buttocks. Unlike plaque psoriasis, these lesions are smooth, red, and inflamed, lacking silvery scales due to the moist environment.
Pustular psoriasis is another form, characterized by pus-filled pustules on red skin. These can be localized to areas like the hands and feet, or become widespread, sometimes with systemic symptoms like fever or fatigue. Erythrodermic psoriasis is a severe, rare form, involving widespread redness, peeling, and itching or burning over much of the body. This can disrupt the skin’s ability to regulate temperature and protect against infection.
Recognizing Signs and Seeking Care
The presence of skin manifestations, especially when severe, extensive, or accompanied by nail changes, can indicate psoriatic arthritis. While these are psoriasis symptoms, their association can clue to joint involvement. Joint symptoms may not always be present when skin symptoms first appear, or they may develop later.
Consult a healthcare professional if you observe new or worsening skin lesions. Seek medical evaluation if these skin changes are accompanied by joint pain, stiffness, or swelling. Early diagnosis of psoriatic arthritis helps control symptoms and prevent long-term joint damage.