“Hiker's feet” in a patient with anti‐PM‐Scl autoantibodies‐associated idiopathic inflammatory myopathy

Abstract

Dear Editors, the term "hiker's feet" was first used in 2017 to refer to hyperkeratosis of the toes and plantar surface of the feet, similar to "mechanic's hands", in the context of idiopathic inflammatory myopathies. Few cases of idiopathic inflammatory myopathies presenting with "hiker's feet"have been described, most of them associated with anti-Jo-1 antibodies, one with anti-MDA-5 antibody and the rest without any autoantibodies. There is no histopathologic description of this cutaneous finding. We report what is to our knowledge the first case of "hiker's feet" with its histopathologic findings in a patient with anti-PM-Scl-associated idiopathic inflammatory myopathy.A 74-year-old woman was referred to the Dermatology Department for the evaluation of corticosteroid-refractory skin lesions on her feet of 4 months duration. She presented with non-pruritic hyperkeratosis and erythema affecting the toes and the soles. She had a history of hypertension, dyslipidemia, chronic atrophic gastritis, and hypothyroidism on treatment with enalapril/hydrochlorothiazide, atorvastatin, cyanocobalamin, levothyroxine. Allergic contact eczema was excluded, and one year later psoriasis was diagnosed and she was started on acitretin. After 4 months, skin lesions had barely improved and the patient reported myalgias, dyspnea and constitutional syndrome so she was admitted to the hospital. Clinical examination revealed severe diffuse hyperkeratosis and erythema affecting the soles and lateral aspect of the feet and