A child came with similar lesions over elbows, shaft of penis and forearm. Shows Pinhead discrete but grouped papules over right elbow. Diagnosis is

Lichen nitidus is a chronic inflammatory disease of unknown cause characterized by large number of 1-2 mm, discrete and uniform, shiny, flat-topped, pale flesh-coloured or reddish-brown papules that may appear as hypopigmented against dark skin. Occasionally, minimal scaling is present or can be induced by rubbing the surface of the papules. Lesions are typically distributed on the penis, geniral area, abdomen and extremities. The disease usually affects children and young adults and is painless and usually nonpruritic, although protracted itching may occur in some cases. It is sometimes referred to by dermatologists as "mini lichen planus". Ref Harrison 20th edition pg 1234