Linear lesions in dermatology.

Linear lesions in dermatology are commonly encountered. They vary in cause; being congenital or acquired; vary in morphology and can present as macules, papules, patches, plaques, vesicles or nodules; they can be inflammatory or non inflammatory; it can be a single lesion which is linear or multiple lesions which are arranged in a linear pattern. The causes for occurrence in a linear pattern include lesions following Blaschko’s lines, blood vessels, lymphatics and dermatomes; due to Koebner’s phenomenon and auto inoculation; external factors; infestations like cutaneous larva migrans and burrows of scabies. We review each of these causes one by one.