Nontuberculous mycobacterial pulmonary disease (NTM-PD) is a challenging infection which is becoming increasingly prevalent, causing significant morbidity and mortality in both immune competent and immune compromised populations. NTM- PD infection caused by ubiquitous organisms in the environment, frequently slow and progressive disease affecting predominantly vulnerable patient populations. Low virulence organisms together with generally their slow growth rate and onset of disease symptoms is often insidious with variable incubation periods making diagnosis difficult. Mycobacterium avium complex, Mycobacterium kansasii, and Mycobacterium xenopi among the slowly growing NTM and Mycobacterium abscessus, the rapidly growing NTM are among the most common organism causing NTM-PD worldwide. Patients with both genetic or acquired structural lung diseases such as cystic fibrosis, chronic obstructive pulmonary disease, non-CF bronchiectasis, previous pulmonary tuberculosis, and lung cancer. Patients with immune suppression due to primary immune deficiency syndromes, immunodeficiency syndromes including AIDS and haematological malignancies are also susceptible to NTM infection.
Diagnosis of NTM-PD requires confirmation by isolation of NTM along with clinical and radiological criteria and appropriate exclusion of other diagnosis. Susceptibility testing is complex and not available for many of the drugs. NTM-PD treatment requires complex and prolonged multi-drug therapy. Recurrence is common with rates of 30–50% being recorded in MAC infection, majority are due to reinfection. Many patients develop persistent chronic infection despite treatment while others succumb to the disease Adjuvant therapies have been tested with little success.
Recently, International societies namely ATS, ERS, ESCMID, IDSA have jointly developed and published guideline on treatment recommendation for NTM-PD in adult.
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