<prompt> Lichen planus is associated with:KoilonychiaTinea versicolorPsoriasisPterygium of nail  <response>: Ans: d Pterygium of nailRef: Fitzpatrick Color Atlas 7th ed. 1008-09 Lichen planus LP is a disease of the skin andor mucous membranes that resembles lichen. It is an anautoimmune disorder. Lichen planus may be categorized as affecting mucosal or cutaneous surfaces. Cutaneous forms are those affecting the skin, scalp, and Nails Pterygium of nail is characteristically seen in lichen planus. Koilonychia is found in Iron deficiency anemia not megaloblastic anemia.Patterns of Nail involvement in different conditions Iron deficiency anemiaKoilonychia Arsenic poisoningMees Line Lichen planusPterygium, Onychia, Onychorrhexis, Pitting PsoriasisPitting of nail thimble nail Oil drop nailsOnycholysis: Detachment of nail plate 