TY - CHAP M1 - Book, Section TI - Porokeratosis A1 - O’Connor, Cathal A1 - O’Regan, Grainne M. A1 - Irvine, Alan D. A2 - Kang, Sewon A2 - Amagai, Masayuki A2 - Bruckner, Anna L. A2 - Enk, Alexander H. A2 - Margolis, David J. A2 - McMichael, Amy J. A2 - Orringer, Jeffrey S. Y1 - 2019 N1 - T2 - Fitzpatrick's Dermatology, 9e AB - AT-A-GLANCEPorokeratosis is a chronic progressive disorders of keratinization characterized clinically by hyperkeratotic papules or plaques surrounded by a threadlike, elevated border that expands centrifugally.Porokeratosis is genetically heterogeneous; the majority are inherited as autosomal dominant traits.At least six clinical variants of porokeratosis have been described.The classic form, porokeratosis of Mibelli, presents in infancy or childhood as asymptomatic, small, brown to skin-colored, annular papules with a characteristic raised border.The most common type, disseminated superficial actinic porokeratosis, presents with multiple papules distributed symmetrically on sun-exposed areas.Linear porokeratosis presents at birth or in childhood with lesions distributed along Blaschko lines.Punctate porokeratosis appears during or after adolescence as 1- to 2-mm papules on the palms or soles.In all variants, a thin column of parakeratotic cells (cornoid lamella) corresponds to the hyperkeratotic border and extends throughout the stratum corneum in histologic sections.Malignant epithelial neoplasms are reported in all subtypes except the punctate variety. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - dermatology.mhmedical.com/content.aspx?aid=1162815557 ER -