Malassezia (Pityrosporon) Folliculitis Occurring During Pregnancy

A 23‐year‐old black woman presented in the 37th week of her first pregnancy complaining of a pruritic rash of 4 months' duration. The lesions appeared acutely on her neck, trunk, and proximal extremities and did not respond to therapy with a topical benzoyi peroxide gel. The patient had been treated for mild facial acne vulgaris since the age of 18 years. Her acne reportedly responded to therapy with topical benzoyi peroxide gel, tretinoin cream, and oral courses of tetracycline. The tetracycline was discontinued when the patient learned that she was pregnant. Otherwise, the patient was in excellent health, without a history of diabetes mellitus or Cushing's syndrome. She was taking no systemic medications during the pregnancy. Physical examination was remarkable for the presence of monomorphous follicular erythematous papules and pustules on the patient's neck, chest, upper back, and proximal extremities (Fig. 1). Comedones and cysts were not apparent. Histopathologic examination of a typical lesion revealed a dilated, plugged hair follicle containing keratinaceous material, acute and chronic inflammatory cells, and spherical to oval budding yeast‐like organisms without hyphal forms (Fig. 2). The organisms were readily apparent on PAS‐stained sections, staining PAS‐positive and diastase resistant (Fig. 3).