Nontuberculous Mycobacteria (NTM)

What is nontuberculous mycobacteria (NTM)?

Nontuberculous mycobacteria (NTM), also known as environmental mycobacteria, atypical mycobacteria, and mycobacteria other than tuberculosis, are organisms that are found naturally in water and soil. They are a non-contagious group of over 100 bacteria that are related to mycobacterium tuberculosis. These organisms prefer warmer conditions because they are better for growth. Evidence suggests that they are only transmitted via the environment and not between people. 
Lung infection from nontuberculous mycobacteria happens when one inhales the organism within the environment. About 10 out of the 100 bacteria included in the nontuberculous mycobacteria cause human respiratory infection. Most people do not get sick after inhaling the organism, but more susceptible individuals are at greater risk for developing a progressive illness/infection. Susceptible individuals may include people with pre-existing respiratory conditions such as chronic obstructive pulmonary disease (COPD), cystic fibrosis (CF), bronchiectasis, alpha-1-antitrypsin, and primary ciliary dyskinesia. The mycobacteria are called “nontuberculous” so that they can be differentiated from the types of mycobacteria that cause tuberculosis.
Symptoms and severity of nontuberculous mycobacterium infections vary from person to person. In rare cases, NTM infections may cause skin, soft tissue, or lymph node inflammation and infection. Since NTM prefer warmer environments, they can grow in hot tubs and even shower heads. The vapors from these waters, when inhaled, can cause infection. These infections can end up being chronic, requiring long term treatment. 
Risk factors
  • Being immunocompromised 
  • Having a pre-existing respiratory condition
  • Being a lung or other organ transplant patient
  • Exposure to NTM in the environment: Most people are exposed in their lifetime and not infected, however. Hot tubs and pools pose even great risk. 
  • Being a smoker
  • Having a pre-existing structural lung disease
  • Age: in North America instances of NTM infection is especially rising in the older adult population
  • Race/ethnicity: NTM infection is more common in Caucasians and Asians. 
  • Having an esophageal disorder such as acid reflux (GERD) because of spilling of gastric contents into the lungs
Diagnosis of NTM infection can be difficult because symptoms may be similar to other respiratory diseases. Confirming a diagnosis of NTM infection is not difficult, however. Diagnosis will typically start with a complete medical history and physical exam by your doctor - with close attention paid to any symptoms you may be having. 
Some other methods that may be used to diagnose NTM infection include:
  • Respiratory specimen culture (most often a culture of one’s coughed up mucus aka sputum) taken to be studied in a lab can provide a definitive diagnosis of NTM infection. A sputum culture can also provide information on the specific bacteria species that is causing the infection which is important when deciding treatment. When a sputum culture is unable to be obtained, an endoscopic examination of one’s respiratory system (bronchoscopy) can be done to obtain a specimen to culture.
  • Imaging tests: A chest X-ray can be the first clue that one has an NTM infection. A computed tomography (CT) scan is done to show more detail than an X-ray. A CT can show nodules and holes in the lung which can indicate a more severe infection.
In more mild cases, treatment may not be required. In more severe cases, the infection is chronic and needs long-term treatment. Specific treatments may vary depending on the species of bacteria one is infected with and the severity of their infection. Treatment usually involves a combination of 2-4 different drugs and needs to be continued for at least 12 months after cultures come back negative. 
Possible treatment methods for NTM infection include:
  • Combinations of antibiotics 
  • Surgical removal of affected lung tissue
  • There are approximately 86,000 cases of NTM infection in the U.S. currently
  • Prevalence of NTM infection in the U.S. grows by approximately 8% each year
  • NTM infection is more common in the U.S. than tuberculosis (TB)
  • There are over 150 different species of NTM, but NTM lung infections are most commonly caused by Mycobacterium avium complex (MAC), Mycobacterium kansasii, and Mycobacterium abscessus. 
about nontuberculous mycobacteria (NTM)

  • "Diagnosing and Treating NTM Pulmonary Disease.” American Lung Association. Lung Health & Diseases, n.d. Web. 30 Aug. 2017.
  • “NTM (Nontuberculous Mycobacteria) Lung Infections.” Insmed Incorporated. Insmed, n.d. Web. 30 Aug. 2017. 
  • “Nontuberculous mycobacteria.” Wikipedia. Wikipedia The Free Encyclopedia, 20 Aug. 2017. Web. 30 Aug. 2017.
  • “Nontuberculous mycobacterial pulmonary infections.” National Center for Biotechnology Information U.S. National Library of Medicine. Journal of Thoracic Disease, 06 Mar. 2014. Web. 30 Aug. 2017. 
  • “Nontuberculous Mycobacterial Lung Disease.” National Organization for Rare Disorders. NORD, 2015. Web. 30 Aug. 2017. 
  • “Non-tuberculous mycobacterial (NTM) Infection.” Kamelhar Pulmonary Medicine. Kamelhar-Teller Pulmonology, n.d. Web. 30 Aug. 2017. 
  • “Treatments & Side Effects.” NTM Info & Research, Inc. NTM Nontuberculous Mycobacteria, n.d. Web. 30 Aug. 2017. 
  • “A Growing Problem.” Insmed. NTM Facts, n.d. Web. 30 Aug. 2017. 
  • "NTM Symptoms, Causes, & Risk Factors.” American Lung Association. Lung Health & Diseases, n.d. Web. 30 Aug. 2017.


NTM are a type of bacteria that occur naturally in the environment (water and soil) which do not cause tuberculosis or leprosy. NTM do cause pulmonary infections that resemble tuberculosis, however. Human disease from NTM is believed to be caused by environmental exposure. There is no evidence that NTM-related infections can be contracted by animal-to-human or human-to-human contact. Check out this infographic to learn more about notuberculous mycobacteria, who is at risk for infection, symptoms, and treatment:
nontuberculous mycobacteria (NTM) pulmonary infections


NOTE: The information on this page and any information found on healtheo360 is not a substitution for professional medical advice, diagnosis or treatment. If you think you may have a medical emergency, CALL 911 immediately. See additional information about our Terms & Conditions.