Adult colloid milium. An underdiagnosed and difficult to treat entity

Millium colloid is a rare cutaneous deposition disorder of unknown aetiology on light-exposed skin. It presents as flesh-coloured or yellow papules. A skin biopsy and light microscopy study is required for diagnosis, with findings of fissured eosinophilic colloid masses in the papillary dermis, with solar elastosis that is separated from the epidermis by a Grenz zone containing normal collagen. There is no single effective treatment. We present a case report of a 42-year-old man with papular lesions on the dorsum of both hands and a history of prolonged sun exposure