Nontuberculous Mycobacteria Infections

What are nontuberculous mycobacteria (NTM) infections?

Nontuberculous mycobacteria (NTM) infections are any illnesses caused by one of the bacteria in the genus (group) Mycobacterium. NTM don’t include Mycobacterium species that cause tuberculosis (M. tuberculosis complex) or leprosy/Hansen’s disease (M. leprae).

NTM are naturally found in dust, soil and water. NTM most commonly infect your lungs (NTM lung disease). But they can also infect your:

• Blood.
• Bones.
• Lymph nodes.
• Skin and soft tissues.

NTM infections can be localized (limited to one part of your body) or disseminated (spread to many parts of your body). But infections outside of your lungs are very rare in people who don’t have a compromised immune system.

What are the symptoms of nontuberculous mycobacteria infections?

Symptoms common to many types of nontuberculous mycobacteria infection include:

• Fever.
• Fatigue (extreme tiredness).
• Weight loss.
• Swollen lymph nodes.

Additional symptoms by location

You might have additional symptoms depending on where you’re infected. These include:

• NTM skin infection: Pain, redness, swelling, sores, ulcers or rash.
• NTM musculoskeletal infection: Joint pain and stiffness.
• NTM lung infection: Cough (sometimes with blood) and shortness of breath.

What causes nontuberculous mycobacteria infections?

M. avium complex (MAC) is the most common cause of nontuberculous mycobacteria infections. Other examples of mycobacteria include:

• M. kansasii.
• M. abscessus complex.
• M. xenopi.

How do you get an NTM infection?

Mycobacteria are found in the environment — like soil and water. You can get an NTM infection from:

• Drinking, bathing or showering in water containing NTM.
• Inhaling mycobacteria from the environment (especially if you have existing lung disease).
• A medical device (like a central venous line) or surgical tools.
• Needles, like those used for injecting medical or nonmedical drugs, or for tattooing.

Because it can take a long time to experience symptoms after exposure to NTM, you might not know where or how you got the infection.

Are nontuberculous mycobacteria infections contagious?

NTM infections are rarely contagious (they don’t spread from person to person).

What are the risk factors for nontuberculous mycobacteria infection?

Most people come in contact with NTM and don’t get sick. But you might be at higher risk for a nontuberculous mycobacterial infection if you:

• Have HIV, cancer or another condition that can weaken your immune system.
• Take immunosuppressive medications.
• Have underlying lung conditions. These include cystic fibrosis, bronchiectasis, asthma and emphysema.
• Have a central venous line, breathing tube, feeding tube or another device that goes into your body.

Women with a low BMI and certain health conditions, like GERD (chronic acid reflux), scoliosis, pectus excavatum or mitral valve prolapse are at an increased risk for pulmonary NTM infections (Lady Windermere syndrome).

What are the complications of nontuberculous mycobacteria infections?

Complications of mycobacteria infections include:

• Lung cavities and abscesses.
• Lung scarring (fibrosis).
• Skin scars.
• Respiratory failure.

How are nontuberculous mycobacteria infections diagnosed?

Healthcare providers diagnose NTM infections based on:

• Your symptoms.
• Your health history.
• Ruling out more common conditions and infections.
• Cultures that look for mycobacteria in your blood, tissue or sputum (mucus coughed up from your lungs or collected during a bronchoscopy).

Tests used to diagnose nontuberculous mycobacteria infections

Depending on where in your body you have symptoms, you might need the following tests or procedures:

• Chest X-rays.
• CT scans (computed tomography scans).
• Bronchoscopy.
• Biopsy.
• Acid-fast bacilli test. Your provider uses a sample of sputum, blood or tissue to look for or grow (culture) mycobacteria.

How do you know if you have nontuberculous mycobacteria?

NTM infections share symptoms with many other illnesses. The only way to know if you have a nontuberculous mycobacteria infection is to see a healthcare provider and undergo testing looking specifically for NTM.

How are nontuberculous mycobacteria infections treated?

Healthcare providers often prescribe a combination of two to three types of antibiotics to treat mycobacteria infections. You may need to take these medications for up to 12 months to make sure the infection is completely gone. You might also need surgery to remove damaged tissue. Treatment for NTM lung infections includes breathing treatments and performing breathing exercises that help cough up bacteria and phlegm (sputum).

Antibiotics used to treat NTM infections

The specific antibiotics your provider prescribes depend on where your infection is and the species (type) of mycobacteria. You might be treated with a combination of:

• Clarithromycin.
• Ethambutol.
• Amikacin liposome suspension for inhalation (ALIS).

Complications and side effects of treatment for NTM infections

Antibiotics can have a number of risks and side effects, especially with long-term use. Tell your provider if you experience side effects or notice any concerning symptoms. Depending on the treatment, you could experience:

• Hearing loss.
• Vision changes.
• Long QT syndrome.
• Liver or kidney damage.

Can nontuberculous mycobacteria infections be prevented?

If you have lung disease or a weakened immune system, you can reduce your risk of NTM infections by avoiding places where the bacteria might live. You might avoid:

• Using hot tubs, particularly in enclosed areas.
• Using sprayers that produce a fine mist you can inhale.
• Working with soil (especially potting soil).
• Getting a tattoo.

What can I expect if I have a nontuberculous mycobacteria infection?

The earlier an NTM infection is found, the easier it is to treat. If you have a mild NTM infection, you may not need treatment. But severe infections sometimes need ongoing treatment for years. Some NTM infections cause chronic (long-term) health problems such as persistent cough and breathing problems. Sometimes, even after successful treatment, the infection could come back (recur).

The outlook for NTM infections depends on the type of NTM causing it, where the infection is and any underlying health conditions. For instance, the five-year mortality (death) rate for NTM lung infections is between 13% and 45%.

When should I see my healthcare provider?

If you have an implanted medical device, lung disease or a weakened immune system, or if you’ve had surgery, ask your healthcare provider what signs of infection you should look out for. Follow up with your provider if you have any concerning symptoms.

When should I go to the ER?

Go to the emergency room if you have any signs of severe illness, including:

• Fever over 103 degrees Fahrenheit or 40 degrees Celsius.
• Difficulty breathing.
• Chest pain.
• Confusion or disorientation.
• A wound or surgical site that’s hot, red, swollen, painful or not healing.

What questions should I ask my doctor?

If you have an NTM infection, you may want to ask your healthcare provider:

• How do I take these medications?
• What are the side effects of these medications and how do I monitor them?
• What new or worsening symptoms should I look out for?
• What else can I do to take care of myself?