Segmental Collagenoma in Tuberous Sclerosis - Think Beyond the Skin: A Rare Case Report.

Collagenomas are connective tissue nevi characterized by an imbalance in the distribution and amount of collagen in the extracellular matrix. Shagreen patch, a collagenoma of tuberous sclerosis, is a classical finding in this genodermatosis (Tuberous Sclerosis). Though the prototypical lesion is a shagreen patch, some individuals manifest only small collagenomas, and these can hinder a diagnosis of tuberous sclerosis and thus mask underlying systemic involvement as was seen in this case we have reported, wherein a 22-year-old male presented with segmental collagenomas over the face and calcified subependymal nodules of the brain on further investigation.