Beyond the "Oil Drop Sign" in Nail Psoriasis

Nov 30, 2015

New research clarifies the presentation and treatment of nail psoriasis for rheumatologists, dermatologists and general practitioners.

Understanding the presentation and treatment of nail psoriasis is key for rheumatologists, dermatologists and general practitioners who might encounter patients with nail psoriasis. A new article in the journal Clinical and Experimental Rheumatology aims to clarify the latest research.Â

Nail psoriasis can affect any portion of the nail, including the nail bed, nail matrix, nail fold and hyponychium, wrote researchers Racheal Manhart and Phoebe Rich, M.D., of the Oregon Dermatology Research Center. Patients usually present in clinic with changes in the nail bed and matrix. These include white spots (leukonychia), red macula in the lunula, and pitting and crumbling of the nail plate. When psoriasis affects the nail bed, it can cause yellowish-orange spots called salmon patch dyschromia, also known as the "oil drop" sign. Nail psoriasis can also cause the nail plate to pull away from the nail bed. (Â©Deviant/Shutterstock.com)

There are multiple scales used to assess nail psoriasis, but the one used in most clinical trials is NAPSI, the Nail Psoriasis Severity Index. This scale uses a quadrant system to record the location and extent of psoriasis of the nail. (Â©JacekDudzinskiShutterstock.com)

The first line of treatment for nail psoriasis is education, Manhart and Rich wrote. Patients should avoid repetitive actions that stress the nail and keep fingernails clipped short so that activities like typing do not put pressure on the nail. Physicians should also urge patients to wear gloves while doing chores or gardening. Nail polish is safe, but acrylic nails should be avoided. Patients also need to be aware that treatment of nail psoriasis takes time. For fingernails, it may take six months or more for damaged areas to grow out. For toenails, it could take up to a year. (Â©TaniaZbrodko/Shutterstock.com)

Treating nail psoriasis is similar to treating skin psoriasis, the authors wrote. Mild cases can be treated with corticosteroids, calcipotriol, tazarotene, tacrolimus creams or the new botanical Indigo Naturalis. Steroid injections into the lesions and phototherapy may be helpful if only a few nails are affected. (Â©P.Kanchana/Shutterstock.com)

If local treatment fails, systemic medications are the next step. But there are differences between effective systemic treatments for skin and nail psoriasis, Manhart and Rich warned. Medications such as cyclosporine A and methotrexate appear to have a limited effect on nail psoriasis. Biologics, on the other hand, have shown much more potential. Studies find that ustekinumab is an effective treatment, and phase 2 and 3 trials of ixekizumab and secukinumab are promising as well. (Â©wavebreakmedia/Shutterstock.com)