Irritant contact dermatitis secondary to fiberglass: an unusual presentation

37‐year‐old white man presented with a 4‐day history of an intensely pruritic eruption on both forearms. The symptoms began immediately after crawling over fiberglass insulation in his attic. The patient had been wearing long pants and a short‐sleeved shirt, exposing his forearms to the insulation. By the third day, pustules had begun to form on both arms. Physical examination revealed multiple erythematous pustules on both forearms Scrapings from a pustule dissolved in 10% potassium hydroxide revealed numerous rectangular refractile crystals which were easily visualized under polarized light ( Fig. 2). A Gram stain of a pustule revealed numerous neutrophils and Gram‐positive cocci in clusters. The patient was diagnosed with fiberglass dermatitis with secondary infection and was treated with a 14‐day course of cephalexin, 250 mg per os four times a day. 2Refractile crystal under polarized light