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Acta Derm Venereol 2021; 101: adv00492 This is an open access article under the CC BY-NC license. www.medicaljournals.se/acta doi: 10.2340/00015555-3851 Society for Publication of Acta Dermato-Venereologica An otherwise healthy 23-year-old man presented with multiple hyperkeratotic papules and comedo-like plugs with a linear distribution on his hands, feet and left knee since birth. The lesions had gradually increased in number and size, with occasional pruritus and pain. There was no family history of similar lesions. Physical examination revealed hyperkeratotic papules and pits with brown keratotic plugs on both hands (Fig. 1A, B), involving the wrists, palmar surfaces and most of the ventral digits, with extension onto the dorsal surface of the digits on both feet (Fig. 1C) including the plantar surfaces, several dorsal toes and medial and lateral borders, and the extensor side of the left knee. Most of the lesions presented with a linear distribution. No extracutaneous involvement was observed. Dermatoscopic examination showed several central whitish and brown cores surrounded by yellow crater-like rings (Fig. 1D).