An insidious preauricular sinus presenting as an infected postauricular cyst.

Preauricular sinuses are common congenital malformations that usually occur at the anterior margin of the ascending limb of the helix. We present three paediatric patients with postauricular infected cysts and coincidentally discovered auricular pits. Single-stage operations were performed to remove the cysts, pits and involved cartilage. Histopathology revealed a preauricular sinus with inflammation. Although uncommon, a postauricular infected cyst may indicate the presence of a preauricular sinus. Detailed physical examination of preauricular pits should be performed, and the operating microscope may aid during surgery to remove remnants and prevent recurrence. An infected preauricular sinus can be effectively treated with single-stage excision.