TB - Glossary of Terms
Glossary of TB Terms
Acid-fast bacilli (AFB) - a class of bacterium of which TB is a member; they are recognized by their unusual staining properties. Seeing these bacterium in a slide of lung sputum is often called "smear positive".
Adverse Reaction - negative side effect resulting from the use of a drug (for example, hepatitis, nausea, headache). Also called a side effect.
Antibiotics - drugs that kill bacteria infecting the body. Not completing the recommended course of antibiotics can create bacteria that is resistant to these drugs.
BCG - bacille Calmette-Guerín; a vaccine to protect against TB, only proven to protect children from the worst forms of TB and it effectiveness decreases in time; may produce small (1-5 mm) skin reactions.
Biopsy - a small amount of body tissue or fluid is removed and then tested for signs of infection.
Cavity - a hole in the lung where TB bacteria have eaten away the surrounding tissue. If a cavity shows up on your chest x-ray, you are more likely to cough up bacteria and be infectious.
Chest x-ray - a picture of the inside of your chest. A chest x-ray is made by exposing a film to x-rays that pass through your chest. A doctor can look at this film to see whether TB bacteria have damaged your lungs.
Contact - a person who has spent time with a person with infectious TB.
Culture - a test to see whether there are TB bacteria in your phlegm or other body fluids. The bacteria from the sputum is put into a media to allow it to reproduce and test for vulnerability to certain antibiotics. This test can take 2 to 4 weeks in most laboratories.
Clinical Evaluation - an evaluation done to find out whether a patient has symptoms of TB disease or is responding to treatment; also done to check for adverse reactions to TB medications.
Continuation Phase - the period after the first 8 weeks of treatment, during which tubercle bacilli that remain after the initial phase are killed.
Daily Regimen - a treatment schedule in which the patient takes a dose of each prescribed medication every day.
DOT-Directly Observed Therapy - health care workers or another designated person watches the TB patient swallow each dose of the prescribed drug. The standard of care for treating active TB disease includes DOT.
Ethambutol - a drug used to treat TB disease. May cause vision problems. Ethambutol should not be given to children who are too young to be monitored for changes in vision.
Extrapulmonary TB - TB disease in any part of the body other than the lungs (for example, the kidney or lymph nodes).
Hepatitis - liver inflammation that can be caused by several drugs used to treat TB infection or disease.
HIV infection - infection with the human immunodeficiency virus, the virus that causes AIDS (acquired immunodeficiency syndrome). A person with both TB infection and HIV infection is at very high risk for TB disease.
Infectious TB - TB disease of the lungs or throat, which can be spread to other people.
Infectious person - a person who can spread TB to others because he or she is coughing TB bacteria into the air.
Initial Phase - the first 8 weeks of treatment, during which most of the tubercle bacilli are killed.
Intermittent Regimen - a treatment schedule in which the patient takes each prescribed medication two or three times weekly at the appropriate dosage.
Isoniazid - the drug most often used for preventive therapy and also used to treat TB disease. Sometimes referred to as INH.
Miliary TB - TB disease that has spread to the whole body through the bloodstream. Also called disseminated TB.
Multi Drug-Resistant TB (MDR TB) - TB that is resistant to isoniazid and rifampin and is more difficult to treat than drug-susceptible TB.
Mycobacterium tuberculosis - the species of bacteria that causes TB infection and TB disease.
PPD - purified protein derivative; see TB skin test.
Pulmonary TB - TB disease that occurs in the lungs, usually producing a cough that lasts longer than 2 weeks. Most TB disease is pulmonary.
Pyrazinamide - drug used to treat TB disease, usually during the initial phase of treatment; should not be given to pregnant women.
Rifampin - drug used to treat TB disease; also used for preventive therapy in people with a positive skin test reaction who have been exposed to isoniazid resistant TB. Rifampin has several possible side effects (for example, hepatitis, turning body fluids orange, drug interactions).
Streptomycin - an injectable drug used to treat TB disease; may cause hearing problems; should not be given to pregnant women.
TB skin test - a test that is often used to detect TB infection. A liquid called tuberculin (PPD) is injected under the skin on the lower part of your arm. It is inspected 2 - 3 days later for any reaction and, if so, carefully measured. If you have a positive reaction to this test, you probably have TB infection. Also called a Mantoux test or PPD.
Smear - a test to see whether there are TB bacteria in your phlegm. To do this test, lab workers smear the phlegm on a glass slide, stain the slide with a special stain, and look for any TB bacteria on the slide. This test usually takes 1 day.
Sputum - phlegm (mucus) coughed up from deep inside the lungs. Sputum is examined for TB bacteria using a smear; part of the sputum can also be used to do a culture.
TB infection - a condition in which TB bacteria are alive but inactive in the body. People with TB infection have no symptoms, don't feel sick, can't spread TB to others, and usually have a positive skin test reaction. But they may develop TB disease later in life if they do not receive preventive therapy.
TB disease - an illness in which TB bacteria are multiplying and attacking different parts of the body. The symptoms of TB disease include weakness, weight loss, fever, no appetite, chills, and sweating at night. Other symptoms of TB disease depend on where in the body the bacteria are growing. If TB disease is in the lungs (pulmonary TB), the symptoms may include a bad cough, pain in the chest, and coughing up blood.
Tuberculin - a liquid (PPD) that is injected under the skin on the lower part of your arm during a TB skin test. If you have TB infection, you will probably have a positive reaction to the tuberculin. See TB skin test.
