A swollen outer ear, accompanied by redness and pain, can be due to inflammation of the ear cartilage, a condition called auricular chondritis, states BootsWebMD. This inflammation can be caused by injury or pressure to the ear resulting from ear piercings, lacerations or surgery complications. In some cases, the cause of a swollen outer ear is polychondritis, a rare, idiopathic condition that causes inflammation of cartilaginous tissue in various parts of the body, particularly the ears, nose and lung airways.
Piercings that perforate the upper third of the ear, an area that is made of cartilaginous tissue, are more likely to become infected than piercings in the ear lobe, explains BootsWebMD. Inflammation is also possible when the ear suffers a blow and blood accumulates between the cartilage and the soft tissue that surrounds the ear, known as perichondrium. An untreated infection of the ear cartilage to can lead to complications such a cauliflower ear.
Perichondritis, in which just the perichondrium is inflamed and infected, is a milder condition but can quickly lead to chondritis if left untreated, warns MedlinePlus. Although at first a red, swollen ear may look like a simple skin infection, it can quickly get worse and spread to the cartilage. Sufferers may also experience fever or drainage of pus from the wound in more severe cases. Early treatment with antibiotics is usually sufficient for recovery, but surgery may be necessary if cartilage becomes infected.