Balanitis xerotica obliterans (BXO) is a dermatological (skin) condition affecting the male genitalia. It was first described by Stuhmer in 1928, though earlier reports describe what may have been the same condition. BXO commonly occurs on the foreskin and glans penis. Atrophic white patches appear on the affected area, and commonly, a whitish ring of indurated (hardened) tissue usually forms near the tip that may prevent retraction.