Nontuberculous Mycobacteria (NTM)

Last Updated 04/22/2021

Authors:Timothy Aksamit, MD; Megan Carreon, MHA, RRT; Charles L. Daley, MD; David E. Griffith, MD; Amy Levinger, MSN, FNP-C; Rosa M. Estrada-Y-Martin, MD, MSc, FCCP

About Nontuberculous Mycobacteria (NTM) lung infections

Key facts about NTM infections
  • People at any age can get an NTM infection.
  • It occurs more frequently in older adults and people with other lung diseases, like bronchiectasis and chronic obstructive pulmonary disease (COPD).
  • If not treated, many NTM infections may cause damage to lung tissue.
  • An NTM infection is not contagious. It cannot be passed from human to human.
  • Treatment for NTM infections generally requires long-term use of antibiotics, often for 1 to 2 years.

Nontuberculous mycobacteria, shortened to NTM, are a type of bacteria found in water and soil. There are more than 180 strains of NTM bacteria. Most do not cause disease except in people with a weakened immune system. You get an NTM infection when you breathe in the bacteria from misty water (for example, in a shower or hot tub) or from soil. If not treated, many people may get a worsening lung infection.

How serious are NTM infections?

About 50,000 to 90,000 people with NTM infections in the United States have NTM lung disease. NTM lung disease is more common in older adults but can affect any age group.

NTM lung infections can become chronic and require ongoing treatment. Severe NTM lung disease can affect a person’s quality of life. Death directly related to NTM lung disease is uncommon.

NTM can get into the lungs from the environment. In most people, NTM are cleared from the lungs naturally and do not cause infection.

In some people, however, NTM infects the airways and lung tissue and causes an infection. Without treatment, many people will develop a progressive lung infection. Cough, shortness of breath, fatigue, and often weight loss are symptoms.

NTM (Nontuberculous mycobacteria) & MAC (Mycobacterium avium complex)

Nontuberculous mycobacteria (NTM) is a group of organisms that includes almost 200 species. Most NTM species do not cause infections in humans, but few a NTM species do, including: 

  • Mycobacterium avium complex (MAC) 
    • M. avium
    • M. intracellulare
  • Mycobacterium abscessus 
  • Mycobacterium kansasii
  • Mycobacterium xenopi

MAC is the most common species of NTM that causes infections in humans, and the lungs are the most common site for infection. 

MAC Lung Disease patient infographic

MAC Infographic

CHEST MAC Lung Disease Patient Mythbuster

MAC Myths Busted

MAC Lung Disease patient checklist

MAC Checklist

Since not all NTM lung infections are treated the same, it’s important to know if MAC or another NTM organism is causing the lung infection so that the appropriate treatment is started.

This educational campaign is produced in partnership with the American College of Chest Physicians and is sponsored by Insmed Incorporated.

Living Well with Nontuberculous Mycobacteria

Living Well with NTM

NTM Infographic

NTM Infographic

NTM Mysth Busted

NTM Myths Busted

The Living well with NTM patient guide will introduce you to Nontubercelous Mycobacteria – its causes, symptoms and risk factors; how it is diagnosed; how it is treated; and how to manage the condition to minimize its impact.

This patient education is supported by an educational grant from Insmed Incorporated. Materials for this patient education guide were contributed by NTM Info & Research.

Symptoms of NTM lung infection

Not everyone with an NTM lung infection has symptoms. However, most people have a combination of lung and other symptoms. The more severe the infection, the more likely you will have symptoms.

People with NTM generally have some or all of these symptoms:

  • Cough
  • Fatigue
  • Night sweats
  • Fever
  • Weight loss and loss of appetite
  • Shortness of breath
  • Coughing up blood
  • Excessive mucus production
  • Wheezing
  • Chest pain
  • Recurring respiratory infections

What causes NTM lung infection?

NTM lung infections are caused by mycobacteria that are found in soil and water. Health care providers do not know why only some people develop NTM lung infections. Most people do not become sick. The people who do get sick from NTM usually have lung disease or a weakened immune system

What are risk factors for NTM lung infection?

NTM infections happen at a higher rate among people with certain risk factors, including:

  • Age. It’s more common in older people.
  • Lung disease. Many people have another underlying lung problem, such as:
  • Genetic diseases. Genetic diseases, including cystic fibrosis, alpha-1 antitrypsin deficiency, and primary ciliary dyskinesia, increase the risk of NTM.
  • Weakened immune system. Illnesses that affect the immune system, such as Sjogren disease and rheumatoid arthritis, may increase the risk of an NTM infection. Certain drugs can weaken the immune system, such as prednisone and other steroids.
  • Medications. Some drugs used to treat rheumatoid arthritis or Crohn disease can increase the risk of getting an NTM infection.
  • Esophageal disorders. Gastroesophageal reflux disease (GERD) and other disorders of the esophagus can increase the risk because of stomach contents leaking into the lungs.
  • Older women. Some women may have an increased risk for NTM. These women share certain physical features that include:
    • White
    • Tall and slender
    • A curved spine
    • Breastbone abnormalities
    • Mitral valve prolapse
  • Environment. The bacteria is often found in places that are warm and wet, like showers, indoor hot tubs and pools, and soil.

Diagnosing NTM lung infection

Diagnosis of NTM infections is often delayed. Symptoms are similar to other lung diseases, such as:

When an NTM infection is suspected, diagnosis is not difficult. A lab test can easily identify an NTM infection. It can also identify which strain of bacteria is causing the disease. The strain will affect the type of treatment.

If you are diagnosed with NTM lung disease, you may never have symptoms. It may take many years to see symptoms. Once symptoms appear, treatment may not completely get rid of all of them. Early diagnosis and treatment are essential for a good outcome.

How is an NTM infection diagnosed?

An evaluation by your provider will likely include:

  • Detailed medical history. If your provider knows your medical history, it may help uncover other lung conditions.
  • Physical examination. Your provider will listen to your lungs to check for wheezing or congestion.
  • Sputum culture. A sample of your sputum, also known as mucus or phlegm, is sent to a lab to test for NTM and identify the strain. This information helps with a targeted treatment. You can cough up the mucus. When you can’t produce mucus, a bronchoscopy may be performed to get a sample to send for testing.
  • Chest X-ray and CT scan. A chest X-ray may provide the first hint that an NTM infection is present. A CT scan shows more detail and can help confirm NTM. The CT scan can show the presence of small nodules. These are sometimes referred to as tree-in-buds because they look like branches.
When should you see your health care provider?

Contact your provider right away if you have a cough that won’t go away along with fatigue, night sweats, shortness of breath, or weight loss. If your cough doesn’t improve with treatment, you may need to see a lung specialist.

Treating NTM lung infections

NTM infections are relatively resistant to antibiotics. They can become more resistant if only one antibiotic is used. Effective treatment usually requires two to three medications. The exact combination of medications depends on the:

  • NTM strain
  • The severity of the infection
  • The results of drug sensitivity tests

Different NTM strains require different treatments:

  • M. avium complex (MAC) and M. kansasii, the most common causes of NTM lung infections, require three medications given either 3 days a week or daily. The timing depends on how severe the infection is.
  • M. abscessus treatment is more complicated and has worse outcomes than MAC and M. kansasii. Many people with M. abscessus infections need several months of treatment with one or two intravenous (IV) medications, oral medications, and sometimes inhaled antibiotics.

Remember, treatment should continue until your sputum culture results have been negative for at least 12 months.

Side effects of medications are common, but most people can finish the prescribed treatment.

For severe infections, you may need surgery to remove the most damaged areas of the lung. If you have a severe NTM lung infection, meet with experts in NTM and discuss your need for surgery. In most cases, surgery can be performed using video-assisted thoracic surgery (VATS).

Download a list a list of terms and medications.

Living with NTM lung infection

Treating an NTM infection can take a long time. There are many things that can affect how you feel. Living with NTM can be hard. You may have chronic coughing, feel tired, or have other side effects from treatment. Many people also feel isolated, anxious, or depressed. A complete cure can be expected with some NTM strains but not with others. Reinfection is common. To avoid becoming infected again, you may need to make some lifestyle changes.

Managing the NTM lung infection

  • Focus on other lung conditions you may have. Many people with an NTM infection have another lung disease, such as bronchiectasis, COPD, or prior tuberculosis. Treatment of these diseases may help improve some of the symptoms of NTM infections, such as cough and shortness of breath.
  • Prevent fatigue. Feeling tired is a common symptom. It is important to stay active. It may also help for you to lose or maintain your weight by eating balanced meals. Use nutritional supplements, if necessary, to get all your daily vitamins and minerals. Staying active and eating healthy foods may help improve your fatigue level.
  • Keep your airways clear. Your doctor or respiratory therapist can teach you ways to reduce mucus in your lungs and keep your airways clear. This is very important for people with bronchiectasis.
  • Prevent infections. Get a flu shot each year. Get pneumonia shots when recommended. Wash your hands often to avoid germs that can lead to other lung infections.
  • Improve air and water quality at home. Keep bathrooms, showers, and steam rooms ventilated. Clean your showerheads regularly. Don’t use humidifiers.
  • Avoid contact with soil. Wear a dust mask to prevent breathing in dirt when gardening. Avoid direct contact with soil

Get the facts about NTM: Myths BUSTED

Leading text


NTM lung disease is easy to diagnose.


The symptoms of NTM often look like symptoms for other illnesses, such as pneumonia. Many doctors are unfamiliar with the disease and aren’t clear about how to diagnose and treat it. The best doctor to evaluate your symptoms is a pulmonologist or infectious disease specialist experienced at treating NTM disease.


NTM lung disease can be treated in a better of weeks or months.


NTM lung disease can be treated in a better of weeks or months.


NTM infections only occur in people with weak immune systems.


Anyone can get NTM at any age. While weakened immune systems from some disease may increase your risk factor, there are other conditions which may contribute to getting NTM lung infection, such as COPD, bronchiectasis or Cystic Fibrosis.


NTM lung infections are treated by taking a single antibiotic.


NTM tends to be resistant to antibiotics and requires a multi-drug regimen of at least three antibiotics to successfully treat the disease. Other simple, at-home treatments may also be recommended to help keep your airways clear (such as nebulizers) and your health strong (including nutrition and exercise).


People with NTM lung disease look unwell.


Many patients with NTM disease look perfectly normal but the infection has taken a toll on their bodies and causes symptoms like fatigue, shortness of breath or coughing. Early detection can help minimize the symptoms, which is why it is important to find a physician who has experience diagnosing and treating NTM lung infection.


NTM infection is contagious.


FACT: NTM infection cannot be spread from human to human.

NTM Myths Busted


NTM infections are serious illnesses that can have a significant impact on your life and that of your families and friends. Depression and anxiety are common for people managing long-term illnesses like these. It is important that you discuss these feelings with your provider and family. Communicating your needs and feelings is important.

The Lung Association recommends patients and caregivers join our Living With Lung Disease Support Community to connect with others facing this disease. You can call the Lung Association’s Lung Helpline at 1-800-LUNGUSA to talk to a trained lung professional who can help answer your questions and connect you with support.

You can also visit the NTM Info & Research website, the not-for-profit foundation for patients with NTM disease. For patients who do not live near a support group, NTMir provides an online forum for patients.

Questions to ask your health care provider

It may be helpful to make notes before your appointment. Consider taking a family member or friend along to the appointment. They can help take notes or ask questions. Questions you may want to ask your provider include:

  • Which strain of NTM do I have?
  • Where in my lungs is the infection?
  • What will happen if I don’t get treated?
  • What medication will I take? How much? For how long?
  • Will I need IV medications?
  • Are there side effects of the treatment? What can I do about them?
  • Should some side effects be reported to you right away?
  • Are there other treatments I can take besides the antibiotics?
  • How will you watch or follow up with me? Will there be tests?
  • When do I need to see you?
  • Can I still take my other prescriptions? (Bring a list of all medications you are taking.)
  • Can I take over-the-counter drugs or supplements?
  • Do I need to make lifestyle changes? What can I do to improve my general health and nutrition?
  • Should I change how I exercise?
  • Should I have surgery to remove the infected part of my lung?
  • What is my chance of healing completely from my infection?

Resources for clinicians

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MAC Mythbuster