Psoriatic Nails

Overview

Psoriatic nails are nail changes that occur as part of psoriasis, a chronic immune-related condition that speeds up the life cycle of skin cells. Psoriasis commonly affects the skin, but it can also affect the fingernails and toenails, sometimes even when there is little or no skin involvement. Nail changes are common in people with psoriasis and are especially frequent in those who also have psoriatic arthritis.

The nail changes range from subtle pitting to marked thickening, discoloration, and separation of the nail from its bed. While psoriatic nails are not dangerous, they can be uncomfortable, affect the appearance and use of the hands, and are sometimes a clue that a person may develop or already has psoriatic arthritis. A variety of treatments can improve the nails, though they often take time to work.

Symptoms

Psoriatic nail changes can affect one or many nails and include:

• Pitting: Small dents or depressions in the nail surface.
• Discoloration: Yellow-brown patches, sometimes called oil drop or salmon spots, under the nail.
• Onycholysis: Lifting or separation of the nail from the nail bed.
• Thickening and crumbling: The nail becomes thick, rough, or breaks apart.
• Ridges and grooves: Lines across or along the nail.
• Debris under the nail: A buildup that can resemble a fungal infection.

Because the changes can look like a fungal nail infection, an accurate diagnosis is important to guide treatment.

Causes

Psoriatic nails are caused by psoriasis affecting the nail unit, the area where the nail is formed and attaches to the finger or toe:

• Immune-driven inflammation: The same overactive immune response that causes skin psoriasis affects the nail-forming tissue.
• Nail matrix involvement: Inflammation in the part of the nail where it grows leads to pitting and ridges.
• Nail bed involvement: Inflammation under the nail causes discoloration, lifting, and debris buildup.

Psoriasis itself is influenced by genetics and immune factors, and certain triggers, such as injury to the nail, can sometimes worsen the changes.

Risk Factors

• Having psoriasis, especially long-standing or severe skin disease
• Having or being at risk of psoriatic arthritis
• A family history of psoriasis
• Injury or trauma to the nails

Diagnosis

Diagnosis is usually based on the appearance of the nails, especially in someone known to have psoriasis. Because nail psoriasis can mimic other conditions:

• Clinical examination: A dermatologist looks for characteristic features such as pitting, oil-drop discoloration, and lifting, and checks the skin and joints.
• Fungal tests: A nail sample may be examined or cultured to rule out a fungal infection, which can look similar or occur alongside psoriasis.
• Biopsy: Rarely needed when the diagnosis is unclear.

Treatment

Treating psoriatic nails can be challenging and usually requires patience, since nails grow slowly. Options include:

• Topical treatments: Prescription creams, ointments, or solutions, such as corticosteroids and vitamin D-based products, applied to the nail and surrounding skin.
• Injections: Corticosteroid injections into the area around the nail for stubborn cases.
• Systemic and biologic therapy: Oral or injectable medicines used for moderate to severe psoriasis or psoriatic arthritis, which often improve the nails as well.
• Nail care: Keeping nails trimmed, protecting them from injury, and moisturizing.

Improvement can take several months. Treating any associated skin disease or arthritis often helps the nails too.

Prevention

• Protect nails from injury, which can trigger or worsen changes
• Keep nails trimmed short and avoid aggressive manicures
• Moisturize the nails and surrounding skin
• Wear gloves for wet work and to protect the hands
• Manage overall psoriasis with your healthcare provider

When to See a Doctor

See a doctor or dermatologist if you have nail changes that bother you, are spreading, or you are unsure whether they are due to psoriasis or a fungal infection, since treatment differs. It is also worth seeking care if you have psoriasis and develop joint pain, stiffness, or swelling, because nail changes can be associated with psoriatic arthritis, which benefits from early diagnosis and treatment.

Related Topics

Frequently Asked Questions

References

1. National Psoriasis Foundation. Nail psoriasis.
2. American Academy of Dermatology Association. Nail psoriasis.
3. MedlinePlus, U.S. National Library of Medicine. Psoriasis.
4. Mayo Clinic. Psoriasis — Symptoms and causes.