How Does Psoriatic Arthritis Affect the Nails?
Nail psoriasis, also known as nail dystrophy, is common in people with psoriasis and even more frequently seen in people with psoriatic arthritis (PsA). Nail psoriasis is not only a cosmetic problem; it affects the structure and function of the nail. It can also result in emotional distress for the person.1
How often does psoriatic arthritis affect the nails?
Psoriasis limited to the nails is uncommon and estimated to occur in only 5-10% of people with psoriasis, although many people who first present with psoriasis only in their nails later develop psoriasis of the skin and/or joints. Nail psoriasis is more likely to occur in adults than children.1
Psoriasis of the skin, scalp and/or nails often occurs before the appearance of PsA, and psoriasis of the nails has been associated with a greater likelihood of developing PsA. Nail lesions occur in about 87% of people with PsA.2
Nail symptoms with psoriatic arthritis
Psoriasis can affect any of the structures of the nail matrix and nail bed, depending on the duration and location of psoriasis within the nail formation. Nail psoriasis is characterized by a number of symptoms, such as:
- Pitting, or small depressions on the nail
- Crumbling, which represents a merging of pitting due to a longer duration of nail psoriasis
- Psoriatic leukonychia, appearing as white spots in the nail
- Red dots in the crescent shape at the base of the nail
- Oil drop or salmon patch discoloration, named because it resembles a drop of oil or is reddish like a salmon
- Nail bed hyperkeratosis, an abnormal thickened layer of skin beneath the nail
- Splinter hemorrhages, small areas of bleeding that run in the direction of nail growth
- Onycholysis, lifting of the nail or separation from the nail bed1,3
- Inability to grasp small objects, tie shoe laces or button clothes
- Altered sense of fine touch
Nail psoriasis is highly visible and can have a substantial impact on the person's quality of life and psychological health.
Treatment for nail symptoms
Health education is an important first step when treating nail psoriasis. It is important that people with PsA avoid activities that cause minor repetitive trauma to the fingertips or nails, which can exacerbate the nail psoriasis. People with PsA are advised to keep affected nails short, especially when typing or playing piano. Wearing gloves while gardening or doing household chores is also recommended. Excessive nail grooming should be avoided.1
Treatment of nail psoriasis includes topical therapies, such as corticosteroids, calcipotriol, tazarotene and tacrolimus creams, which may be helpful in mild or early cases. Light therapy may be helpful when only a few nails are affected.1
In moderate to severe cases, systemic treatments are used. Traditional systemic medications that are used to treat psoriasis, such as methotrexate, Cyclosporine and acetritin, are more effective in treating plaques on the skin than they are in clearing nail psoriasis. Several biologic medications have proven effective in treating nail psoriasis, including etanercept (Enbrel), adalimumab (Humira), infliximab (Remicade), certolizumab pegol (Cimzia), secukinumab (Cosentyx), ixekizumab (Taltz), and ustekinumab (Stelara). 1 The FDA has also recently approved Inflectra (infliximab-dyyb), a biosimilar to infliximab, for the treatment of PsA.5