Mycobacterium xenopi

Mycobacterium xenopi is a species of bacteria in the genus Mycobacterium. It is a slow-growing, thermophilic bacterium that is capable of surviving in a wide range of environments, including water and soil. M. xenopi is a member of the group of nontuberculous mycobacteria (NTM), also known as environmental mycobacteria or atypical mycobacteria.

History

Mycobacterium xenopi was first isolated in 1959 from skin lesions in a Xenopus laevis, a species of African clawed frog. The bacterium was named after the frog from which it was first isolated.

Characteristics

M. xenopi is a rod-shaped bacterium that is acid-fast, meaning it retains certain stains even after being washed with an acid solution. This characteristic is common among members of the genus Mycobacterium. The bacterium is also thermophilic, meaning it thrives in high temperatures, typically around 45 degrees Celsius.

Pathogenicity

M. xenopi is an opportunistic pathogen, meaning it can cause disease in individuals with weakened immune systems. In humans, it can cause a form of lung disease similar to tuberculosis, known as M. xenopi pulmonary disease. Symptoms can include chronic cough, weight loss, and fatigue. The bacterium can also cause disseminated disease, where it spreads to multiple organs in the body.

Diagnosis and Treatment

Diagnosis of M. xenopi infection typically involves culturing the bacterium from a patient's sputum or tissue sample. Treatment usually involves a combination of antibiotics, including rifampin, ethambutol, and isoniazid. However, M. xenopi is often resistant to many common antibiotics, making treatment challenging.

Epidemiology

M. xenopi is found worldwide, but is most common in Europe and North America. It is often found in water, including tap water, and can survive in hot water systems. The bacterium is not believed to be transmitted from person to person, but rather from the environment to humans.

See Also

• Nontuberculous mycobacteria
• Mycobacterium avium complex
• Mycobacterium kansasii