Multidrug-resistant TB (MDR-TB) is caused by a TB germ that is resistant to at least isoniazid and rifampin, the two most potent TB drugs. These drugs are used to treat all persons with TB disease.
Extensively drug-resistant TB (XDR-TB) is a rare type of MDR-TB that is resistant to isoniazid and rifampin, plus any fluoroquinolone and at least one of three injectable second-line drugs (i.e. amikacin, kanamycin, or capreomycin). Because XDR-TB is resistant to the most potent TB drugs, patients are left with treatment options that are much less effective. XDR-TB is of special concern for persons with HIV infection or other conditions that can weaken the immune system. These persons are more likely to develop TB disease once they are infected, and also have a higher risk of death once they develop TB.
Both MDR and XDR-TB can only be diagnosed in a well-equipped laboratory. Symptoms of XDR-TB are no different from ordinary TB: a cough with thick, cloudy mucus (or sputum), sometimes with blood, for more than 2 weeks; fever, chills, and night sweats; fatigue and muscle weakness; weight loss; and in some cases shortness of breath and chest pain. If you have these symptoms, it does not mean you have MDR/XDR-TB. But it does mean you must go and see a doctor for a check-up. If you are already on treatment for TB, and at least some of these symptoms are not improving after a few weeks of medication, you should inform your clinician or nurse.
The most important thing a person can do to prevent the spread of MDR-TB is to take all their medications exactly as prescribed by their health-care provider. No doses should be missed and treatment should never be stopped early. Patients should tell their health-care provider if they are having trouble taking the medications. If patients plan to travel, they should talk to their health-care providers and make sure they have enough medicine to last while away. Health-care providers can help prevent MDR-TB by quickly diagnosing cases, following recommended treatment guidelines, monitoring patients’ response to treatment, and making sure therapy is completed. Another way to prevent getting MDR-TB is to avoid exposure to known MDR-TB patients in closed or crowded places such as hospitals, prisons, or homeless shelters. If you work in hospitals or healthcare settings where TB patients are likely to be seen, you should consult infection control or occupational health experts. Ask about administrative and environmental procedures for preventing exposure to TB. Once those procedures are implemented, additional measures could include using personal respiratory protective equipment.
If you are pregnant and have active TB, you should start treatment as soon as TB is suspected. Although the TB drugs used during treatment cross the placenta, they do not appear to have any harmful effects on the fetus. TB medications such as isoniazid, rifampin, and ethambutol are often used for treatment during pregnancy. While dealing with TB during pregnancy is not easy, proper treatment is crucial for the health of the mother and the baby. Untreated TB disease represents a greater hazard to a pregnant woman and her fetus than does its treatment. Treatment of pregnant women should be initiated whenever the probability of TB is moderate to high. Infants born to women with untreated TB may be of lower birth weight than those born to women without TB and, in rare circumstances the infant may be born with TB. The drug Streptomycin should not be used because it has been shown to have harmful effects on the fetus. In most cases, pyrazinamide is also not recommended because its effect on the fetus is unknown. Frequently Asked Questions about Tuberculosis. (2013). [ebook] New Delhi-110002, India: Regional Office for South-East Asia, World Health Organization. Available at: http://www.searo.who.int/about/administration_structure/cds/ en/index.html [Accessed 1 Jan. 2018].