TUBERCULOSIS

Tuberculosis

Tuberculosis

Introduction

Tuberculosis (TB) is an infectious disease caused by a germ (bacterium) called Mycobacterium tuberculosis. This germ primarily affects the lungs and may infect anyone at any age.In the United States, the number of TB cases steadily decreased until 1986 when an increase was noted; TB has continued to rise since. Today, ten million individuals are infected in the U.S., as evidenced by positive skin tests, with approximately 26,000 new cases of active disease each year. The increase in TB cases is related to HIV/AIDS, homelessness, drug abuse and immigration of persons with active infections(Dormandy 2000).

The disease

TB is a contagious or infectious disease that is spread from person-to- person. A person is usually infected by inhaling the germs which have been sprayed into the air by someone with the active disease who coughs. However, inhaling the germ does not usually mean you will develop active disease. A person's natural body defenses are usually able to control the infection so that it does not cause disease. In this case, the person would be infected, but not have active disease. Only about 10% of those infected will actually develop TB in their lifetimes. Active disease can occur in an infected person when the body's resistance is low or if there is a large or prolonged exposure to the germs that overcome the body's natural defenses. The body's response to active TB infection produces inflammation which can eventually damage the lungs. The amount of damage may be quite extensive, yet the symptoms may be minimal. The usual symptoms of disease due to TB are(Ryan 1993):

Fever

Night sweats

Cough

Loss of appetite

Weight Loss

Blood in the sputum (phlegm)

Loss of energy

Treatment of TB

Individuals with a positive tuberculin skin test may or may not receive preventive drug therapy depending on the exposure history, the timing of the skin test conversion (when the test changes from negative to positive) and other factors in the individual's medical history. When it is known that a person has recently been in close contact with an individual with active tuberculosis and has developed a positive tuberculin skin test, preventive treatment is advisable due to a relatively high risk of developing active disease. Isoniazid (INH) may be prescribed for six to nine months as preventive treatment and for twelve months in persons who are HIV positive(Blumberg Leonard Jasmer 2005).

Since the advent of anti-tuberculosis drugs in the 1940s, the treatment of drug susceptible ...