A child was brought to OPD with red follicular hyperkeratotic papules over knee.These are areas of normal skin in between.The child also has thickening of palms & soles.The most likely diagnosis is
Red follicular hyperkeratotic lesions with "islands of sparing" and keratoderma(thickened palms & soles) points out to the diagnosis of Pityriasis rubra pilaris.
Pityriasis rosea
Lichen nitidus
Pityriasis rubra pilaris
Lichen planus.