L3- Pharmacological of Antituberculosis

Tuberculosis

-Tuberculosis (TB) remains the leading cause of death worldwide from a single infectious disease agent. Indeed up to 1/2 of the world’s population is infected with TB.

-The registered number of new cases of TB worldwide roughly correlates with economic conditions: the highest incidences are seen in those countries of Africa, Asia, and Latin America with the lowest gross national products.

-WHO estimates that eight million people get TB every year, of whom 95% live in developing countries. An estimated 2 million people die from TB every year

-It is estimated that between 2000 and 2020, nearly one billion people will be newly infected, 200 million people will get sick, and 35 million will die from TB – if control is not further strengthened.

-The mechanisms, pathogenesis, and prophylaxis knowledge is minimal.

-After a century of decline TB is increasing and there are strains emerging which are resistant to antibiotics.

-This excess of cases is attributable to

the changes in the social structure in cities,
the human immunodeficiency virus epidemic ,
the failure of most cities to improve public health programs,
the economic cost of treating

-TB is an ancient infectious disease caused by Mycobacterium tuberculosis. It has been known since 1000 B.C., so it not a new disease. Since TB is a disease of respiratory transmission, optimal conditions for transmission include:

overcrowding
poor personal hygiene
poor public hygiene

-With the increased incidence of AIDS, TB has become more a problem in the U.S., and the world.

-It is currently estimated that 1/2 of the world’s population (3.1 billion) is infected with Mycobacterium tuberculosis. Mycobacterium avium complex is associated with AIDS related TB.

Transmission

-Pulmonary tuberculosis is a disease of respiratory transmission, Patients with the active disease (bacilli) expel them into the air by:

coughing,
sneezing,
shouting,
or any other way that will expel bacilli into the air

-Once inhaled by a tuberculin free person, the bacilli multiply 4 -6 weeks and spreads throughout the body.

-The bacilli implant in areas of high partial pressure of oxygen:

lung
renal cortex
reticuloendothelial system

-This is known as the primary infection.

-The patient will heal and a scar will appear in the infected loci.

-There will also be a few viable bacilli/spores may remain in these areas (particularly in the lung).

-The bacteria at this time goes into a dormant state, as long as the person’s immune system remains active and functions normally, this person isn’t bothered by the dormant bacillus.

-When a person’s immune system is depressed., a secondary reactivation occurs.

-85-90% of the cases seen which are of secondary reactivation type occurs in the lungs.