<prompt> A child presents with a solitary white well-defined patch on his right thigh. Diagnosis isPiebaldismAlbinismNevus achromicusAcral vitiligo  <response>: Information is this question are :-Lesion is on thighUnilateral lesion Isolated lesion on Right thighBoth these suggest Nevus achromicus, i.e. Nevus acromicus involves :-Trunk and proximal extremity thigh in this questionLesion is unilateralAlso keep in mind that, though Nevus achromicus presents since birth, it may be missed at birth and the patient may present in childhood 