Perichondritis of external ear

**Definition:** Perichondritis is an infection of the tissue surrounding the cartilage of the outer ear, the perichondrium. It usually results from injury to the ear from ear surgery, ear piercing (especially piercing of the cartilage), or trauma from contact sports. The most common bacterium causing perichondritis is Pseudomonas aeruginosa. Presenting features include pain, redness and swelling of the auricle, and fever.