NTMs are closely related to tuberculosis bacteria and can (but do not need to) cause infectious diseases in humans. They are called "nontuberculous mycobacteria" (NTMs) to distinguish them from tuberculosis bacteria. There are approximately 200 different species and subspecies of these bacteria. Patients with bronchiectasis (dilation of the airways) are particularly affected. It is not uncommon for a chronic infection to develop. The most common pathogens are Mycobacterium avium complex, Mycobacterium kansasii, Mycobacterium xenopi and Mycobacterium abscessus. Unlike tuberculosis, there is practically no known risk of infection with nontuberculous mycobacteria.
"In some countries, more cases are now caused by NTMs than by tuberculosis bacteria," said Christoph Lange, clinical director of the Research Center Borstel. "It is not always clear when, how and for how long people need treatment." International recommendations for the treatment of lung diseases caused by NTMs, based on expert opinions rather than scientific evidence, have not been published since 2007. "It was high time for new guidelines," according to Christoph Lange.
A panel of experts from the leading international societies involved in infectious diseases and pulmonary medicine (ATS, ERS, ESCMID, IDSA) has created a new, evidence-based guideline for the treatment of patients suffering from the most common NTM pathogens. They used the principles of evidence-based medicine with 'PICO' questions (Population, Intervention, Comparison, Outcome). The new recommendations are based on an extensive and systematic literature search, and are graded according to current scientific evidence. A total of thirty-one recommendations has been made for the treatment of NTM lung disease. The new guideline is intended for medical specialists who treat patients with NTM lung disease, including experts in infectious and pulmonary diseases.