Simple Onycholysis and the Disappearing Nail Bed

Abstract

Onycholysis refers to separation, most commonly distal, of the nail plate from the underlying nail structures. If it is distal, there is separation from the nail bed. It is less commonly proximal. The term onychomadesis refers to proximal separation of the nail plate from the nail matrix area. Simple onycholysis of the fingernails most commonly presents to the practitioner. Of topical antifungal medications, solutions are best, then lotions are next best. Most patients are troubled by the appearance of the nails, and usually the condition has been present for weeks to months before patients will seek medical advice. For onycholysis to occur, there must be a disruption of the adherence of the various components of the nail unit to each other. To establish the diagnosis of simple onycholysis, other primary dermatoses affecting the nail unit, such as nail unit psoriasis or nail unit lichen planus must be excluded. The role of Candida in onycholysis is controversial, and Candida can commonly be found on culturing nails with onycholysis. Treatment consists of a multifaceted approach. The most important aspect is an irritant avoidance regimen. The nails should be clipped back to the point of attachment at the nail bed to avoid additional trauma. Avoidance of nail cosmetics is important to help improve the onycholysis. Use of nail cosmetics may be resumed 1 month after the affected nails have returned to normal. Aside from the behavioral changes described above, topical antifungal medications can be helpful in hastening the resolution of onycholysis. Oral fluconazole may be of benefit in recalcitrant cases, especially when Candida has been cultured and/or pseudohyphae are found. For cases not responding to therapy, biopsy should be employed. The biopsy may show signs of a primary inflammatory dermatosis of the nail unit, or in the case of recalcitrant onycholysis of a single nail, may identify a tumor of the nail bed as the ultimate cause of the onycholysis. Long standing onycholysis may result in the disappearing nail bed.