Nail psoriasis is a chronic nail disorder that requires personalized treatment. General prophylactic measures are suggested for all patients. Topical treatment is considered when treating a few-nail disease, with involvement of 3 or fewer nails, without joint involvement and without (or with mild) skin psoriasis. The ideal formulation should be ointment, solution, or foam. When moderate to severe skin psoriasis or psoriatic arthritis coexists, systemic treatment is suggested. This also should be considered when more than 3 nails are affected or significant impairment of quality of life is present. Conventional systemic agents, biologics, and small molecules are highly efficacious.

Nail involvement in psoriasis is common, and the severity of it does not always parallel the intensity of cutaneous disease. We created a consensus group, of which the aim was to provide practical recommendations for the treatment of nail psoriasis in patients without skin psoriasis or with mild skin lesions with no indication for a systemic treatment. This collaborative process was conducted by an international panel of dermatologists with special expertise in nail disorders, using formal consensus methods. During this process, the panel strived to establish an agreement regarding the definition of nail psoriasis, the severity of nail psoriasis, and treatment response. Treatment recommendations are provided regarding nail psoriasis severity and matrix or bed involvement. Few-nail disease was considered as nail psoriasis affecting ≤3 nails. In the case of matrix involvement only, intralesional steroid injections were considered the treatment of choice. Topical steroids alone or in combination with topical vitamin D analogues were suggested for nail psoriasis limited to the nail bed. For the systemic treatment of nail psoriasis acitretin, methotrexate, cyclosporine, small molecules, and biologics may be employed.

Nail involvement is an extremely common feature of psoriasis and affects approximately 10-78% of psoriasis patients with 5-10% of patients having isolated nail psoriasis. However, it is often an overlooked feature in the management of nail psoriasis, despite the significant burden it places on the patients as a result of functional impairment of manual dexterity, pain, and psychological stress. Affected nail plates often thicken and crumble, and because they are very visible, patients tend to avoid normal day-to-day activities and social interactions. Importantly, 70-80% of patients with psoriatic arthritis have nail psoriasis. In this overview, we review the clinical manifestations of psoriasis affecting the nails, the common differential diagnosis of nail psoriasis, Nail Psoriasis Severity Index and the various diagnostic aids for diagnosing nail psoriasis especially, the cases with isolated nail involvement. We have also discussed the available treatment options, including the topical, physical, systemic, and biological modalities, in great detail in order to equip the present day dermatologist in dealing with a big clinical challenge, that is, management of nail psoriasis.