Family doctor

What is Otitis Externa?

Otitis externa means inflammation of the ear canal. This is usually due to some water entering the ear canal of a susceptible person. Water softens the skin lining the ear canal and this softened skin may become infected by bacteria or fungi. These bacteria and fungi reside on the surface of healthy skin throughout the body. Only when one of these bugs invades damaged skin does infection set in. Another common cause of otitis externa is trauma to the ear canal. Frequently this trauma is minor, for example, from using a cotton bud to "clean" the ear canal, itching the ear canal with a match stick or the car keys or even a finger.

Sometimes skin conditions such as psoriasis and dermatitis may also affect the skin of the ear canal. An uncommon cause of otitis externa is a reaction to certain ear drops or ointments used in the ear canal, for example, neomycin or BIPP.

Occasionally, especially in the case of fungal otitis externa, the fungus may live on the surface of a hearing aid mould and result in a relapse of the condition following apparent successful treatment. Rarely certain viruses, for example, the shingles virus varicella zoster virus, may infect the ear canal.

How do I know I have Otitis Externa?

The simple answer is "you don't know for sure." However certain symptoms commonly occur:

• Itchy ears
• Ear ache-especially if the ear ache is worsened by pulling the ear.
• Ear discharge - if this occurs it is never profuse
• Hearing loss - may occur if the ear canal swells closed.

If you suspect you have otitis externa see your doctor. He or she will be able to confirm the diagnosis and treat you. If the condition is severe or if you fail to get better your doctor may refer you to an Otolaryngologist-Head and Neck Surgeon (Ear Nose Throat Surgeon).

What else can happen?

• The infection can spread
• The ear may become red, sore and swollen.
• The area in front of or behind the ear may become red, sore and swollen.
• You may develop a sore lump (gland) usually high in the neck.
• You may feel unwell with a fever, nauseated, tired and lethargic.

How is Otitis Externa treated?

Doctors treat this condition in the following ways:

1. A swab is often taken from the ear canal in order to determine which bug is involved.

2. The ear canal is cleaned. There are three main ways of doing this:

• Syringing with warm water
• Cleaning the ear canal with a little probe
• Suctioning the ear canal under a microscope

Usually the ear canal needs to be cleaned on several occasions. Sometimes syringing the ear canal can result in worsening the condition as the water may encourage the bugs to grow if the ear canal is not dried thoroughly afterwards.

3. Antibiotic and Steroid ear drops (Usually combined in one product) should usually be used three times per day and at least six drops each time. Sometimes the doctor may need to change the ear drops to a better one depending on which bug grows on the swab. Most mild cases are simply treated in this way which is usually very effective.

4. Keep the ear dry. You must keep all water out of the ear canal until after the infection has settled. This is the most common cause of failed treatment. This includes shower water. It is best not to wash your hair too often. Try washing your hair carefully over the hand basin. You may like to try holding a paper or polystyrene cup around your ear and wash your hair away from the cup. Some people use cotton wool dipped in Vaseline and placed in the ear near the opening of the ear canal, or ear plugs. Both of these methods require extra care as they usually result in leakage.

5. Pain relief medication such as paracetamol, codeine or anti-inflammatories may be required as swelling within the ear canal is restricted by the walls of the ear canal and pain can become severe.

6. Oral antibiotics are required only if the infection has spread beyond the ear canal. In severe cases admission to hospital for intravenous antibiotics may be required.

What can I do to prevent it coming back?

As even minor trauma may cause otitis externa, it is imperative that you stop using cotton buds and stop scratching your ear. If swimming is the cause of your otitis externa you will need to stop swimming at least for a while - usually a minimum of four to six weeks to allow the ear wax to return. The wax in the ear canal is formed from special glands and performs a vital role in the protection of the ear canal from infection. Sometimes alcohol ear drops used after swimming can help prevent further attacks. Ear plugs may also be used to help keep water out of the ear canal. Most ear plugs however leak a little. Also swimming under the water is dangerous with ear plugs as the pressure changes may force the ear plugs into the ear causing damage to the ear drum and or the middle ear.

Swimmer's ear

Swimmer's ear is a colloquial term that may be used to refer to two separate conditions:

1. Otitis externa occurring as a result of water entering the ear canal while swimming.

2. External ear canal exostoses.

Cold water entering the ear canal may result in stimulation of the bony part of the ear canal to grow resulting in "exostoses". These are bony lumps projecting into the lumen of the ear canal. They may be small or large. Exostoses may result in itching, ear ache or even hearing loss if they block the ear canal.

Treatment of exostoses require referral to an Otolaryngologist-Head and Neck Surgeon. He will usually clean the ear canals with a small suction device under a microscope. He may prescribe you antibiotic and steroid ear drops. He may recommend surgery.

Surgery is done under general anaesthetic and involves enlarging the ear canal. Following surgery it usually takes several months for the ear canal to heal completely. During this time you will be advised not to swim. The surgery is usually very successful however there are risks (complications). The complications are uncommon but include damage to the facial nerve resulting in a weak or paralysed face, damage to the ear drum and loss of hearing. Sometimes exostoses may recur especially if swimming in cold water continues.

The ear canal

The ear canal is about one inch (2.5 cm) long and connects the outside world with the ear drum. The ear drum separates the ear canal from the middle ear. The ear canal is lined with skin. The outer part of the ear canal contains special wax glands. The wax helps protect the ear canal from infection. The ear canal is surrounded by bone around the inner part and cartilage around its outer part.

Ear wax

As already mentioned, ear wax is made by special wax glands in the outer part of the ear canal. Wax is normal and healthy in the outer ear canal and helps prevent ear canal infections (otitis externa). The skin of the ear canal grows from the ear drum outwards carrying the ear wax with it. This is the only place in the body where skin grows this way.

Cleaning the ears

First of all, most ears do not need to be cleaned. I can almost hear some of you cry out in horror. But it is true. The ear is a very clever organ. It is actually self cleaning. Please do not clean your ears - especially not with cotton buds. You will get a little wax out on the end of the cotton bud, but because cotton buds are about the same diameter as the ear canal most of the wax just gets pushed deeper into the ear canal where it can cause problems. Remember the wax is made only in the outer part of the ear canal. Furthermore, no matter how gentle you are, you are very likely to cause minor damage to the skin of the ear canal and this frequently leads to an ear canal infection. Using cotton buds does interfere with the usual self cleaning mechanism of the ear causing problems with the ears own natural cleaning properties.

Too much wax

Too much wax may block the ear canal. This can be very painful especially if the wax is hard. If the ear canal blocks completely, it is difficult for sound to get through and your hearing may decrease. If you have too much wax try some wax dissolving ear drops (for example Waxsol or 5% sodium bicarbonate ear drops). If the wax still does not shift after a few days, see your general practitioner. He may try syringing your ears or use a small wax hook to remove the wax. If all else fails he may refer you to an Otolaryngologist-Head and Neck Surgeon for suction removal of the wax under a microscope.

Too little wax

Too little wax may result in repeated ear canal infections. The treatment for too little wax is to stop removing the wax from the ears. Sometimes oily ear drops including olive oil ear drops help.

Getting help

For more information, contact your local family doctor or ask about referral to an Otolaryngologist-Head and Neck Surgeon.