Pruritic papules on the nose in a 25-year-old female

Porokeratoses—A Comprehensive Review on the Genetics and Metabolomics, Imaging Methods and Management of Common Clinical Variants

“…Infundibulocentric parakeratotic columns with consumption of the underlying granular layer are recognised as histological hallmarks of the disease. Apoptotic basal keratinocytes (dyskeratosis) and focal interface lichenoid dermatitis can be observed [241,525,526,[529][530][531]533,535,536,539]. In one case, a mild increase in dermal mucin deposition was noted [526].…”

“…There was no sex predominance noted in the reported cases and the peak morbidity was noted in middle-aged individuals (range from 5 to 85 years) [525,529,530,537]. Speculatively, UV radiation might be involved in pathogenesis, as some cases displayed worsening with sun exposure or developed over sunexposed sites [524,525,529,533,534]. In a patient with Sturge-Weber syndrome, FP caused secondary alopecia due to follicular hyperkeratosis and perifolliculitis [528].…”

“…Small (usually <1 cm in diameter), static, either itchy or asymptomatic, well-defined, erythematous, violet, pinkish, skin-coloured, brownish or dusky folliculocentric papules and/or nodules with a raised keratin rim may localise on sun-exposed and sun-unexposed sites (excluding the palms and soles) [241,[525][526][527][529][530][531][532], and occasionally may be accompanied by follicular spicules [523,528]. Rare, limited FP cases with exclusive nasal skin [531,[533][534][535][536] or scalp involvement [537] were also reported. The former seems to be more common in young adults and is speculated to be a distinct subvariant [531].…”

“…Various modalities were utilised in FP, yet all of them provided little to no effect. These included cryotherapy [529], topical steroids [526,533], topical pimecrolimus cream (twice per day; 2 months) [539], topical 5-FU (twice per day; 4 months) [530], imiquimod 5% cream (1 case treated once per day for 2 weeks) [532,533], cholesterol/lovastatin ointment (unknown concentration and regimen) [530], tretinoin cream [528] and ketoconazole shampoo [528]. No effect was achieved with systemic treatment with oral hydroxychloroquine (200 mg twice per day) [526] and acitretin (unknown regimen) [528].…”