Tuberculosis is a bacterial disease usually affecting the lungs (pulmonary TB). Other parts of the body can also be affected, for example, Iymph nodes, kidneys, bones, joints, etc. (extrapulmonary TB).
Tuberculosis can affect anyone of any age. Immunocompromised individuals such as those with AIDS (or those infected with the human immunodeficiency virus ‹ HIV) are at increased risk.
Tuberculosis is spread through the air. When a person with tuberculosis, who is not taking tuberculosis medication, coughs or sneezes, the germs get into the air. Prolonged exposure to the tuberculosis organisms is normally necessary for infection to occur.
Tuberculosis infection may result after close contact with a person who has tuberculosis disease. Tuberculosis infection is determined by a significant reaction to the mantoux skin test with no symptoms of tuberculosis, and no TB organisms found in the sputum. Tuberculosis disease is characterized by the appearance of symptoms, a significant reaction to a mantoux skin test and organisms found in the sputum. In order to spread the TB germs, a person must have TB disease. Having TB infection is not enough to spread the germ. Tuberculosis may last for a lifetime as an infection, never developing into disease.
The symptoms of TB include a low-grade fever, night sweats, fatigue, weight loss and a persistent cough. Some people may not have obvious symptoms.
Most people infected with the germ that causes TB never develop active TB. If active TB does develop, it can occur two to three months after infection or years later. The risk of active disease lessens as time passes.
A person with TB disease may remain contagious until he/she has been on appropriate treatment for several weeks. However, a person with TB infection, but not disease, cannot spread the infection to others, since there are no TB germs in the sputum.
Preventive: People infected with TB should be evaluated for a course of preventive therapy, which usually includes taking an antituberculosis medication for six to 12 months. The exact preventive therapy plan must be determined by a physician. Curative: People with active TB disease must complete a course of curative therapy. Initial treatment includes at least four anti-TB drugs for a minimum of six months. Medications may be altered based on laboratory test results. The exact medication plan must be determined by a physician.
HIV infection, when it occurs in tandem with TB infection, is the strongest factor in the development of TB disease. People with medical risk factors which increase the chance of developing TB disease, once TB infection has occurred, should be skin tested for TB. Their skin test results should be clearly noted in their medical record. These medical risk factors include: diabetes mellitus, prolonged corticosteroid therapy, immunosuppressive therapy, cancer, silicosis and being 10 percent or more below ideal body weight.
In addition to spreading the disease to others, an untreated person may become severely ill or die.
The most important way to stop the spread of tuberculosis is to cover the mouth and nose when coughing, and to take all the TB medicine exactly as prescribed by the physician.
This refers to the ability of some strains of TB to grow and multiply even in the presence of certain drugs which would normally kill them.
People who have been exposed to a case of MDR-TB, especially if they are immunocompromised, are at the risk for developing MDR-TB. Other people who may develop drug resistant tuberculosis include TB patients who have failed to take antituberculosis medications as prescribed, TB patients who have been prescribed an ineffective treatment plan and people who have been treated previously for TB.
For patients with disease due to drug resistant organisms, expert consultation from a specialist in treating drug resistant TB should be obtained. Patients with drug resistant disease should be treated with a minimum of two or three drugs to which their organisms are susceptible. It is presently unknown whether preventive therapy can effectively prevent the development of active TB disease in people who are infected with MDR-TB strains. Immunocompromised people who are infected with MDR-TB are currently being treated with two to three drugs to which the strain is likely to be susceptible. Recommendations concerning preventive therapy for people who have been infected with MDR-TB are being developed by the U.S. Centers for Disease Control (CDC).
The most important ways to stop the spread of MDR-TB include educating the TB patient to cover the mouth and nose when coughing, providing adequate treatment for people with MDR-TB and providing directly observed administration of antituberculosis medications for people who are unwilling or unable to comply with prescribed drug plans.
Source: NY State Department of Health