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Actinomycosis is a long-term infection that causes sores. Read about its causes and treatment options..

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Actinomycosis is a long-term infection that causes sores, or abscesses, in the body’s soft tissues. Actinomycosis is usually found in the:

  • mouth
  • nose
  • throat
  • lungs
  • stomach
  • intestines

Actinomycosis rarely appears elsewhere in the body. However, it can spread from the initial infected area to other parts of the body if illness or injury damages your tissue. Actinomycosis isn’t contagious. It’s primarily found in the tropical areas of the world.

What Are the Symptoms of Actinomycosis?

If your mouth tissue is infected, it can cause what’s commonly known as “lumpy jaw.” A hard lump can be felt in the jaw. The lump itself isn’t typically painful. However, it can result in a painful skin abscess that first appears as a reddish bruise at the site. Actinomycosis can also cause muscle spasms in the jaw or a “locked jaw.” If this happens, the mouth cannot open in a normal way.

The other symptoms of actinomycosis are:

  • a fever
  • weight loss
  • lumps on the neck or face
  • draining sores on the skin
  • excess sinus drainage
  • coughing
  • chest pain

What Causes Actinomycosis?

Actinomycosis is a rare infection, especially in the United States. Since the infection spreads so slowly, actinomycosis was first thought to be a fungal infection. But a family of bacteria known as Actinomycetaceae causes it. The bacteria in this family include:

  • Actinomyces israelii
  • Actinomyces naeslundii
  • Actinomyces viscosus
  • Actinomyces odontolyticus

These bacteria naturally live in your body cavities like your nose and throat but don’t usually cause infection unless they can break through the protective lining of your body cavities.

What Are the Risk Factors for Actinomycosis?

You have an increased risk of developing actinomycosis if you:

  • have a damaged immune system from medications or another illness
  • are malnourished
  • neglect dental care after dental surgery or trauma to the mouth or jaw

One of the most common causes of actinomycosis is an oral or a dental abscess. If you’ve recently had an oral abscess, you should see your doctor right away. Women who’ve used an intrauterine device (IUD) for birth control are also considered at higher risk.

How Is Actinomycosis Diagnosed?

Actinomycosis is usually diagnosed through a fluid or tissue sample from the affected area. Your doctor uses a microscope to check the sample for Actinomyces bacteria. Any such bacteria appear as yellowish granules.

How Is Actinomycosis Treated?

Antibiotics are the primary treatment for actinomycosis. High doses of penicillin are usually necessary to cure the infection. If you’re allergic to penicillin, your doctor can give you other antibiotics, such as:

  • tetracycline
  • clindamycin
  • erythromycin

It can take up to a year for the antibiotics to completely cure the infection.

Any skin eruptions, or abscesses, from the infection may need to be drained or removed. If you developed actinomycosis due to the use of an IUD, the device should be removed to prevent further infection.

Notify your doctor immediately if you have the symptoms of actinomycosis. Early, aggressive treatment decreases your likelihood of developing long-term complications and requiring surgery.

Potential Long-Term Complications

Actinomycosis starts in the soft tissues of the body, but it can infect any surrounding bone if it’s left untreated. Surgery may be necessary to remove any infected bone. If the infection resides in the nasal sinuses, surgery may be required to remove damaged bone and tissue.

In rare cases, actinomycosis in the nasal sinuses can reach the brain. This may lead to another serious type of infection called meningitis.

Preventing Actinomycosis

One of the best ways to prevent actinomycosis is to practice good oral hygiene. Schedule regular visits with your dentist so that they can spot potential problems. If you get proper treatment for actinomycosis, it’s highly curable and you’ll likely make a full recovery.

Written by: Carmella Wint and Matthew Solan
Edited by:
Medically Reviewed by:
Published: Jul 25, 2012
Published By: Healthline Networks, Inc.
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