Tuberculosis (TB)

Tuberculosis Summary
Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis bacteria. Symptoms include weakness, fever, weight loss, night sweats and in worse cases, chest pain, shortness of breath, and coughing up blood. A person with an active infection (a positive TB skin test, abnormal chest x-ray and TB bacteria in their sputum) requires treatment with izoniazid, rifampin, ethambutol and pyrazinaide.
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Tuberculosis facts

  • Tuberculosis (TB) is an infection, primarily in the lungs (a pneumonia), caused by bacteria called Mycobacterium tuberculosis. It is spread usually from person to person by breathing infected air during close contact.
  • TB can remain in an inactive (dormant) state for years without causing symptoms or spreading to other people.
  • When the immune system of a patient with dormant TB is weakened, the TB can become active (reactivate) and cause infection in the lungs or other parts of the body.
  • The risk factors for acquiring TB include close-contact situations, alcohol and IV drug abuse, and certain diseases (for example, diabetes, cancer, and HIV) and occupations (for example, health-care workers).
  • The most common symptoms and signs of TB are fatigue, fever, weight loss, coughing, hemoptysis, and night sweats.
  • The diagnosis of TB involves skin tests, chest X-rays, sputum analysis (smear and culture), and PCR tests to detect the genetic material of the causative bacteria.
  • Inactive tuberculosis may be treated with an antibiotic, isoniazid (INH), to prevent the TB infection from becoming active.
  • Active TB is treated, usually successfully, with INH in combination with one or more of several drugs, including rifampin (Rifadin), ethambutol (Myambutol), pyrazinamide, and streptomycin.
  • Drug-resistant TB is a serious, as yet unsolved, public-health problem, especially in Southeast Asia, the countries of the former Soviet Union, Africa, and in prison populations. Poor patient compliance, lack of detection of resistant strains, and unavailable therapy are key reasons for the development of drug-resistant TB.
  • The occurrence of HIV has been responsible for an increased frequency of tuberculosis. Control of HIV in the future, however, should substantially decrease the frequency of TB.
Medically Reviewed by a Doctor on 1/15/2014

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Tuberculosis - Diagnosis Question: How was the diagnosis of your tuberculosis established?
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