Nontuberculous mycobacteria (NTM) are mycobacteria other than M. tuberculosis (the cause of tuberculosis) and M. leprae (the cause of leprosy). NTM are also referred to as atypical mycobacteria, mycobacteria other than tuberculosis (MOTT), or environmental mycobacteria.

Although anyone can get an NTM infection, NTM are opportunistic pathogens placing some groups at increased risk, including those with underlying lung disease or depressed immune systems. These pathogens are typically not transmitted person-to-person. However, person-to-person transmission of M. abscessus has been reported in patients with cystic fibrosis.

NTM are environmental organisms that can be found in soil, dust, and water including natural water sources (such as lakes, rivers, and streams) and municipal water sources (such as water that people drink or shower in). NTM can form difficult-to-eliminate biofilms, which are collections of microorganisms that stick to each other, and adhere to surfaces in moist environments, such as the insides of plumbing in buildings.

Symptoms

• NTMs can cause infections in a wide variety of body sites, most commonly the lungs and in the following areas:
  • Skin and soft tissue (typically following surgery, trauma, injection of medications or other substances)
  • Device associated infections (e.g., central line associated bloodstream infection, exit site infections, pacemaker pocket site infections, etc.)
  • Lymph nodes (most commonly in children)
  • Blood or other usually sterile locations in the body (disseminated) (most commonly in immunocompromised patients, such as those with HIV or AIDS, but may also be due to invasive medical devices or procedures)
• Symptoms can be vague and nonspecific, such as:
  • Fever
  • Weight loss
  • Night sweats
  • Decreased appetite
  • Loss of energy
• Other symptoms depend on the site of infection and can include cough, shortness of breath, blood in the sputum, and rashes.

Overview

Delays in recognizing outbreaks of extrapulmonary NTM can occur because of:

• the long period of time between exposure and symptom onset
• the nonspecific symptomatology
• the act that patients often present to different healthcare facilities

This can results in delays in public health actions and further infections. Health departments should therefore consider adding extrapulmonary NTM infections to the list of reportable conditions in their jurisdiction.

Reporting of extrapulmonary NTM infections can lead to timely outbreak detection and implementation of public health interventions to decrease the risk of new infections. Jurisdictions that have added extrapulmonary NTM infections to the list of conditions which are required to be reported to the health department have been able to analyze surveillance data to identify and promptly respond to NTM outbreaks.

Outbreaks of extrapulmonary NTM infections have occurred in a number of settings, and are usually due to a water source.

Settings with increased risk of NTM infections include:

• Tattoo parlors
• Nail salons
• Hot tubs or spas
• Healthcare settings

NTM outbreaks have been reported in healthcare settings due to the ability of NTM to form biofilms in hospital plumbing and on medical devices. Healthcare-associated outbreaks often result from breaches in infection control practices that allow patients to be exposed to contaminated water during invasive procedures such as injections, infusions, or surgeries. Healthcare-associated NTM outbreaks can also result from contaminated medical equipment, such as bronchoscopes or heater-cooler devices used in cardiac surgery. NTM outbreaks can occur in many different clinical settings and result from a wide range of medical procedures and practices including:

• Surgery
  • Breast surgery
  • Heart surgery, including infections related to heater-cooler devices
  • Eye surgery with exposure to consumer-grade humidifiers
• Dental procedures
• Medical tourism
• Cosmetic surgery
• Medicine compounding and mixing
• Medication preparation
• Injection preparation and administration
• Central line placement and maintenance
• Manufacturing of medical products