Mycobacterium abscessus

Mycobacterium abscessus is a species of Mycobacterium known to cause non-tuberculous mycobacterial infection. It is a rapidly growing mycobacterium (RGM) and is found in water, soil, and dust. It is often referred to as a 'chronic pneumonia' pathogen, as it primarily causes lung disease in people with structural lung disease, such as cystic fibrosis, although it can also cause skin and soft tissue infections and healthcare-associated infections.

Classification

Mycobacterium abscessus is a member of the Mycobacterium abscessus complex, a group of Mycobacterium species that are closely related. The complex also includes Mycobacterium massiliense and Mycobacterium bolletii. These species are differentiated by their genetic makeup and their varying responses to different antibiotics.

Pathogenesis

Mycobacterium abscessus is an opportunistic pathogen, meaning it primarily causes disease in individuals with a compromised immune system or structural lung disease. It is resistant to many antibiotics, making infections difficult to treat. The bacterium can form biofilms, which are communities of bacteria that are protected from the immune system and antibiotics.

Clinical Manifestations

The most common disease caused by Mycobacterium abscessus is pulmonary disease, which can present as a chronic pneumonia. Symptoms may include a persistent cough, fatigue, shortness of breath, and weight loss. The bacterium can also cause skin and soft tissue infections, often following surgery or injury. In healthcare settings, it can cause infections associated with medical procedures, such as catheter infections.

Treatment

Treatment of Mycobacterium abscessus infections is challenging due to the bacterium's inherent resistance to many antibiotics. A combination of antibiotics is typically used, often including macrolides, aminoglycosides, and tetracyclines. Treatment duration can be lengthy, often requiring several months of therapy.

See Also

• Mycobacterium
• Non-tuberculous mycobacterial infection
• Cystic fibrosis
• Biofilm