Mycobacterium Infections (Tuberculosis)

Mycobacterium infections are caused by bacteria from the Mycobacterium genus. These organisms are acid-fast bacilli that grow slowly and can persist in the environment.
The most clinically important species include:

• Mycobacterium tuberculosis (M. tuberculosis) → Causes tuberculosis (TB), usually affecting the lungs but can spread systemically.

• Mycobacterium leprae → Causes leprosy (Hansen’s disease), affecting skin, peripheral nerves, and mucous membranes.

• Nontuberculous Mycobacteria (NTM) → Includes species like M. avium complex (MAC), M. kansasii, M. abscessus, and others. These are opportunistic pathogens, found in soil, water, and dust, and often infect immunocompromised individuals.

Risk factors include:

• Weakened immune system (HIV/AIDS, organ transplant, long-term steroid use)

• Chronic lung diseases (COPD, cystic fibrosis, bronchiectasis)

• Exposure to endemic environments (crowded living conditions for TB, contaminated water for NTM)

Tuberculosis (M. tuberculosis)

• Persistent cough (>2–3 weeks)

• Hemoptysis (coughing up blood)

• Chest pain

• Fever, night sweats

• Weight loss, fatigue

Nontuberculous Mycobacteria (NTM)

• Chronic cough and sputum production

• Shortness of breath

• Fatigue and weight loss

• May mimic TB or other chronic lung diseases

Leprosy (M. leprae)

• Skin lesions (hypopigmented or reddish patches, numbness)

• Peripheral nerve thickening and damage → numbness, weakness

• Eye involvement in advanced disease

Symptoms typically differ with each patient which is why it’s important to consult a physician who will work with you to meet your individual needs. To discuss your health with Dr. Mike Czarnecki, “The Lung Doc”, please call us at (423) 710-3864 or schedule your appointment online.

• History & Physical Exam: Exposure history, immune status, endemic travel.

• Laboratory Tests:

  • Acid-fast bacillus (AFB) smear and culture (gold standard, but cultures can take weeks).

  • Nucleic acid amplification tests (NAATs) for rapid TB diagnosis.

  • Interferon-Gamma Release Assays (IGRAs) or tuberculin skin test (TST) for latent TB infection.

• Imaging:

  • Chest X-ray / CT scan to identify pulmonary infiltrates, cavitations, or nodules.

• Histopathology: Biopsy may show granulomatous inflammation.

• Special tests for leprosy: Skin smears or biopsy showing acid-fast bacilli.

Tuberculosis (M. tuberculosis)

• First-line regimen:

  • RIPE therapy: Rifampin, Isoniazid, Pyrazinamide, Ethambutol (usually 6 months or more).

• Drug-resistant TB: Requires second-line drugs (fluoroquinolones, bedaquiline, linezolid, cycloserine, etc.).

• Latent TB: Treated with isoniazid or rifampin monotherapy to prevent progression.

Nontuberculous Mycobacteria (NTM)

• Depends on species, but often involves macrolides (azithromycin/clarithromycin) + rifampin + ethambutol.

• May require prolonged therapy (12 months or longer after culture conversion).

• Severe or refractory cases may need surgical intervention (e.g., lung resection).

Leprosy (M. leprae)

• Multidrug therapy (MDT) recommended by WHO:

  • Rifampin + Dapsone + Clofazimine.

  • Duration: 6–12 months for paucibacillary cases, up to 2 years for multibacillary disease.

• Corticosteroids or thalidomide may be used for inflammatory complications (e.g., erythema nodosum leprosum).