Abnormal follicular keratinization: follicular wall cells fail to desquamate to the surface in the normal manner. • Sebum over production secondary to androgen • Propionibacterium acnes infection; they grow in the sebum-cell mixture. comedone extraction, intralesional cortisone injection (for papulonodules, cysts), oral contraceptives (esp. antiandrogenic such as cyproterone acetate), pho…