This is the first American report, to our knowledge, of a case of acne aestivalis, which occurred in a woman with a recurrent acneform eruption in summertime. The histopathologic sequence was very similar to that found in cases of steroid acne; namely, a focal necrosis of the follicular epithelium was followed by the formation of a comedo. No cause was found. Treatment with tretinoin brought about regression of the lesions.
Mills OH, Kligman AM. Acne Aestivalis. Arch Dermatol. 1975;111(7):891-892. doi:10.1001/archderm.1975.01630190081008