A Rare Case Report of Dermatomyositis Accompanied by Blisters

We report a patient with dermatomyositis who developed blisters. The patient was a female, 51 years old. She came to our hospital because of edematous purplish erythema on the face, neck, trunk, and extremities that itched for 1 month. Histopathology of the lesions showed: squamous epithelial tissue, hyperkeratosis of the epidermis, mild thickening of the stratum spinosum, liquefaction and degeneration of the basal cells, perivascular lymphocytes in the dermis, plasma cell infiltration; myofibers of varying thicknesses, disappearance of transverse striations, and lymphocytic infiltration of interstitial muscles. Diagnosis: dermatomyositis. Water blisters appeared on the skin lesions of the patient with dermatomyositis. Given that the probability of dermatomyositis being accompanied by a tumor is approximately 10% - 20%, this is considered a serious condition by modern medicine. Therefore, we conducted a series of examinations, including immunohistochemistry, to determine the source of the blisters.