Nail changes due to common skin diseases
| CONDITION | CHARACTERISTIC NAIL CHANGES |
|---|---|
| Psoriasis | Irregular large and deep nail pits Salmon patches (oil-drop sign) of the nail bed (yellow–orange discoloration) Onycholysis Might also have subungual hyperkeratosis, nail plate thickening, and splinter hemorrhages |
| Lichen planus | Nail thinning, ridging, and fissuring Dorsal pterygium (adhesion of the proximal nail fold to the nail bed) |
| Alopecia areata | Geometric small, superficial, and regularly distributed nail pits Erythema of the lunula |
| Darier disease | Longitudinal erythronychia Distal V-shaped nail plate nicking |
| Trachyonychia | Twenty-nail dystrophy Nail roughness and excessive longitudinal ridging Idiopathic but might be a manifestation of alopecia areata, psoriasis, or lichen planus |