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Histology of acne lesions

John L. Bezzant,M.D.

This is an artist reproduction of what is seen histologically in various acne lesions: The closed comedo (top center) can rupture and form a pustule (mid-left), or a red papule (mid-right), or a large red nodule (bottom center). It appears that the degree of inflammatory response to the ruptured comedo is genetically modulated, i.e., bad acne in parents or grandparents often leads to bad acne in their progeny.