You are leaving Medscape Education
Cancel Continue
Log in to save activities Your saved activities will show here so that you can easily access them whenever you're ready. Log in here CME & Education Log in to keep track of your credits.

Table 4.  

Clinical Significance of Nontuberculous Mycobacteria Isolates from Nonpulmonary Sites, Queensland, Australia, 2005*

Table 3.  

Clinical Significance of Nontuberculous Mycobacteria Isolates from Pulmonary Sites, Queensland, Australia, 2005*

Table 2.  

Significance of Nontuberculous Mycobacteria Isolates as Botified, Queensland, Australia, 1999 and 2005*

Table 1.  

Comparison of Numbers of Nontuberculous Mycobacteria Isolates in 1999 and 2005, Queensland, Australia*


Changing Epidemiology of Pulmonary Nontuberculous Mycobacteria Infections

  • Authors: Rachel M. Thomson, MD
  • CME Released: 9/21/2010
  • Valid for credit through: 9/21/2011, 11:59 PM EST
Start Activity

Target Audience and Goal Statement

This activity is intended for primary care clinicians, infectious disease specialists, pulmonologists, and other specialists who care for patients at risk for NTM infection.

The goal of this activity is to review recent patterns of NTM infection since the 1980s, and changes in epidemiology of pulmonary disease due to NTM.

Upon completion of this activity, participants will be able to:

  1. Identify the prevalence and epidemiology of nontuberculous mycobacteria (NTM) infection and traditional risk factors and presentation of pulmonary NTM infection
  2. Construct an appropriate diagnostic strategy for patients with suspected NTM


As an organization accredited by the ACCME, Medscape, LLC, requires everyone who is in a position to control the content of an education activity to disclose all relevant financial relationships with any commercial interest. The ACCME defines "relevant financial relationships" as financial relationships in any amount, occurring within the past 12 months, including financial relationships of a spouse or life partner, that could create a conflict of interest.

Medscape, LLC, encourages Authors to identify investigational products or off-label uses of products regulated by the US Food and Drug Administration, at first mention and where appropriate in the content.


  • Rachel M. Thomson, MD

    on behalf of the NTM working group at the QLD TB Control Centre and QLD Mycobacterial Reference Laboratory, QLD Tuberculosis Control Centre, Brisbane, Australia


    Disclosure: Rachel M. Thomson, MD, has disclosed no relevant financial relationships.


  • Beverly D. Merritt

    Technical Writer/Editor, Emerging Infectious Diseases


    Disclosure: Beverly D. Merritt has disclosed no relevant financial relationships.

CME Author(s)

  • Désirée Lie, MD, MSEd

    Clinical Professor; Director, Research and Faculty Development, University of California, Irvine


    Disclosure: Désirée Lie, MD, MSEd, has disclosed the following relevant financial relationship:
    Served as a nonproduct speaker for: "Topics in Health" for Merck Speaker Services

CME Reviewer(s)

  • Sarah Fleischman

    CME Program Manager, Medscape, LLC


    Disclosure: Sarah Fleischman has disclosed no relevant financial relationships.

  • Laurie E. Scudder, DNP, NP

    CME Accreditation Coordinator, Medscape, LLC


    Disclosure: Laurie E. Scudder, DNP, NP, has disclosed no relevant financial relationships.

Accreditation Statements

    For Physicians

  • This activity has been planned and implemented in accordance with the Essential Areas and policies of the Accreditation Council for Continuing Medical Education through the joint sponsorship of Medscape, LLC and Emerging Infectious Diseases. Medscape, LLC is accredited by the ACCME to provide continuing medical education for physicians.

    Medscape, LLC designates this educational activity for a maximum of 0.50 AMA PRA Category 1 Credit(s)™ . Physicians should only claim credit commensurate with the extent of their participation in the activity.

    Medscape, LLC staff have disclosed that they have no relevant financial relationships.

    Contact This Provider

For questions regarding the content of this activity, contact the accredited provider for this CME/CE activity noted above. For technical assistance, contact [email protected]

Instructions for Participation and Credit

There are no fees for participating in or receiving credit for this online educational activity. For information on applicability and acceptance of continuing education credit for this activity, please consult your professional licensing board.

This activity is designed to be completed within the time designated on the title page; physicians should claim only those credits that reflect the time actually spent in the activity. To successfully earn credit, participants must complete the activity online during the valid credit period that is noted on the title page.

Follow these steps to earn CME/CE credit*:

  1. Read the target audience, learning objectives, and author disclosures.
  2. Study the educational content online or printed out.
  3. Online, choose the best answer to each test question. To receive a certificate, you must receive a passing score as designated at the top of the test. MedscapeCME encourages you to complete the Activity Evaluation to provide feedback for future programming.

You may now view or print the certificate from your CME/CE Tracker. You may print the certificate but you cannot alter it. Credits will be tallied in your CME/CE Tracker and archived for 6 years; at any point within this time period you can print out the tally as well as the certificates by accessing "Edit Your Profile" at the top of your Medscape homepage.

*The credit that you receive is based on your user profile.


Changing Epidemiology of Pulmonary Nontuberculous Mycobacteria Infections

Authors: Rachel M. Thomson, MDFaculty and Disclosures

CME Released: 9/21/2010

Valid for credit through: 9/21/2011, 11:59 PM EST


Abstract and Introduction


Nontuberculous mycobacteria (NTM) disease is a notifiable condition in Queensland, Australia. Mycobacterial isolates that require species identification are forwarded to the Queensland Mycobacterial Reference Laboratory, providing a central opportunity to capture statewide data on the epidemiology of NTM disease. We compared isolates obtained in 1999 and 2005 and used data from the Queensland notification scheme to report the clinical relevance of these isolates. The incidence of notified cases of clinically significant pulmonary disease rose from 2.2 (1999) to 3.2 (2005) per 100,000 population. The pattern of disease has changed from predominantly cavitary disease in middle-aged men who smoke to fibronodular disease in elderly women. Mycobacterium intracellulare is the main pathogen associated with the increase in isolates speciated in Queensland.


Worldwide, pulmonary disease caused by nontuberculous mycobacteria (NTM) appears to be increasing,[1–4] yet accurate data to support this assumption are difficult to produce. Patients traditionally described are middle-aged men with underlying chronic lung disease, such as chronic obstructive pulmonary disease, who have upper lobe cavity formation and nodules of various sizes. An increasing number of patients have nodules, bronchiolitis, and bronchiectasis involving the middle lobe and lingula. These patients are more commonly female nonsmokers and have no preexisting lung disease.[5,6]

NTM disease is not a reportable condition in most countries because no evidence of human-to-human transmission exists; therefore, it is not considered a public health concern. However, the organisms are ubiquitous in the environment, and substantial evidence shows that the environmental niche for Mycobacterium intracellulare (the most common pulmonary pathogen) is in biofilms lining suburban water pipes. Many NTM pathogens have been isolated from drinking water.[7] Some clinicians believe the condition should be classified as an environmental health concern, similar to that caused by Legionella spp.

Globally, geographic variability in environmental exposure and prevalence of NTM disease is significant.[8] Without detailed clinical information, differentiating between contamination of specimens, colonization/infection, and disease is difficult; laboratory reports of isolates do not always reflect the true incidence of disease. To determine if disease is present, sputum specimens and often a bronchoscopic sample of a patient’s lower respiratory tract must be collected. In addition, computed tomography scanning and clinical appointments with primary care providers and specialists are needed. Because this investigative process is costly to the healthcare system and the patient, accurate epidemiologic data on this condition should be of interest to public health experts.

Studies of avian versus human Mantoux testing in schoolchildren have shown that exposure to NTM organisms is common in Queensland.[9–11] Therefore, since the introduction of TB control services, disease caused by NTM in Queensland has been notifiable. This practice has been continued primarily to avoid confounding of smear-positive cases with TB. The notification process provides a unique opportunity to study the clinical significance of isolates positive for NTM and the features such as age and sex, symptoms, underlying conditions, and radiology results of  patients with disease, avoiding the inherent bias that occurs in case series that are reported by tertiary and quaternary referral centers. The incidence of clinically reported cases of pulmonary disease caused by M. avium complex (MAC) in Queensland has been increasing (1985, 0.63/100,000 population; 1994, 1.21/100,000; and 1999, 2.2/100,000). In 2005, the Queensland Tuberculosis Control Centre (QTBCC) revised the notification process to ensure collection of meaningful clinical data and follow-up of clinically significant NTM cases.

Table of Contents

  1. Abstract and Introduction
  2. Methods
  3. Results
  4. Discussion