Mycobacterium avium is a slow-growing, rod-shaped bacterium that belongs to the genus Mycobacterium. Together with Mycobacterium intracellulare, this Gram-positive pathogen belongs to the Mycobacterium avium complex (MAC) and to the group of non-tuberculous mycobacteria (NTM).
An Infection with Mycobacterium avium can cause symptoms similar to those of tuberculosis:
Pneumonia with persistent cough, feeling of weakness, and weight loss
Lymphadenopathy (abnormal swelling of lymph nodes)
An increased risk of disease or complications exists for individuals with pre-existing conditions whose immune system is already weakened, such as patients with cystic fibrosis.
Mycobacterium avium occurs ubiquitously, especially in water and soil. The bacteria belong to the biofilm formers.
Relevance of pathogen in transmission in endoscopy
Gastroenterology: Not relevant
Pulmonology: Very high
Ear, nose, and throat: High
Urology: Not relevant
Relevance for endoscope surveillance
High concern organism
The pathogen is transmitted in the air, through contaminated food and water, and in biofilm.
Non‐tuberculous mycobacteria (NTM), such as Mycobacterium avium, can also be spread and transmitted in healthcare facilities through water. The water used for final rinsing of the endoscope must therefore be microbiologically controlled to prevent a recontamination of the endoscope.
Resistance to antibiotics
Mycobacterium avium exhibits high resistance to most antibiotics. In the case of monotherapies, rapid development of resistance can occur.
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To K. et al. General Overview of Nontuberculous Mycobacteria Opportunistic Pathogens: Mycobacterium avium and Mycobacterium abscessus, J. Clin. Med. 2020, 9(8), 2541.