Anatomy of an Ear Infection Slideshow Pictures Medical Illustration of the Ear Image Collection Tinnitus (Ringing of the Ears) Slideshow Pictures

Medical Author:

Siamak T. Nabili, MD, MPH

Siamak T. Nabili, MD, MPH

Dr. Nabili received his undergraduate degree from the University of California, San Diego (UCSD), majoring in chemistry and biochemistry. He then completed his graduate degree at the University of California, Los Angeles (UCLA). His graduate training included a specialized fellowship in public health where his research focused on environmental health and health-care delivery and management.

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Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Swimmer's Ear Causes

The skin lining the ear canal and outer ear serves as a barrier against infection from bacteria and fungi. The ear is protected against infection because the lining is slightly acidic. The lining is also a physical barrier that protects against excessive moisture.

Any break in the skin lining can lead to infection, allowing bacteria or fungi to invade the outer ear.

The barrier can become broken and lead to an infection in the following ways:

• When you attempt to clean your ears with cotton-tipped swabs or other objects inserted in the ear, the skin lining of the ear canal may break. This can also remove the protective ear was from the ear canal.

• Excessive moisture in the ear canal from showering or swimming also alters the acidic environment of the ear canal, and allows for the invasion of bacteria or fungi. This is the reason this condition happens mainly in the summer months, and hence, is called swimmer's ear.
  
  
• Ear plugs, hearing aids, headphones, and other devices that may be inserted into the ear canal may increase the risk of swimmer's ear.

• Chemicals such as hair dyes, bleaches, and shampoos may irritate the ear canal and alter its protective properties. An infection can result.

Generally, any inflammation of the outer ear canal, such as infections, allergies, or skin conditions, can lead to swimmer's ear.

The most common bacteria responsible for outer ear infection are Staphylococcus aureus and Pseudomonas aeruginosa. Other bacteria are less common. In minority of cases (less than 10%), a fungus is the cause of swimmer's ear.