TuberculosisPresented byVivian Pham and Vivian Nguyen

What is tuberculosis?• Definition: an infectious disease that mainly affects the

lungs but can also involve other organs such as the kidney, spine, and brain. If not treated properly, tuberculosis disease can be fatal.

• Often called TB and was called consumption in the past.

• Was once ranked among the one of the most common causes of death in the world, and was once the leading cause of death in the United States.

• Today, improved methods of prevention, detection, diagnosis, and treatment have greatly reduced both the number of people who get the disease and the number of people who die from it.

• However, tuberculosis remains a major concern in developing countries where these improved methods are not widely available.

Demographics

• Tuberculosis can strike people of all ages and races, but those who have a greater risk are:o homeless or undernourished peopleo those with immune systems weakened by diseases such as cancer

or AIDS, or by HIV, the virus that causes AIDS.

• More specifically, populations with a greater risk are:o the African-American Communityo Children under age 15, especially younger childreno International Travelerso Pregnant Womeno Those in correctional facilities (jail)

• The disease can also afflict animals, especially such livestock as cattle, hogs, and poultry.

Causes & Spread of TB

• A patient with untreated, active TB can infect an estimated 15 people in a year.

• TB is spread through the air o Infected person coughs, sneezes, speaks, or

sings and releases bacteria into air• TB is NOT spread by

o shaking handso sharing food or drinko touching toilet seatso sharing toothbrusheso kissing

Causes & Spread of TB

• Mycobacterium tuberculosis (M. tb) enters respiratory tract and attacks macrophages in lung cellso Body reacts with immune response and

can sterilize M. tb into latent phase by surrounding it with scar tissue

o Compromises to immune system can turn latent phase into disease

• Disease can lead to pneumonia in the lungs, inflammation of lymph nodes, and infection in other parts of the body

Signs & Symptoms

• People with latent TB do not show any signs of illness and cannot spread the disease to others.

• Symptoms of TB Disease:o Bad cough lasting more than 3 weekso Chest paino Coughing up blood or sputumo Weakness/fatigue, weight loss, loss of

appetiteo Fever, chills, night sweats

Risk Factors for Disease

• TB will generally remain latent unless immune system is compromised

• Risks include:o Infected by HIV or other conditions that

weaken the immune systemo Live/work/spent extended time in place

where TB is commono Drug and alcohol abuseo Infected with tuberculosis previously,

especially if not treated correctly

Tests & Treatment• TB Skin Test

o Determines if person has been infected by M. tb

o Positive: skin reacts to the tuberculin fluid injected

o Does not distinguish if infection is latent or disease

• Blood test for reactions to bacterium can also be used

• Additional tests after infection is determined to distinguish latent infection or diseaseo Disease diagnosed by medical history,

physical examination, chest x-ray, and other laboratory tests

Tests & Treatment• Treatment of Latent Tuberculosis Infection (TLTBI)

o medication that is given to people who have latent TB to prevent them from developing TB disease

o taken for at least 9 months• Initial drug regimen for treating disease includes:

o isoniazid, rifampin, pyrazinamide, and ethambutol

o Multiple drugs to prevent drug resistanceo Directly Observed Therapy used to ensure

patients adhere to treatment fully• Drug resistance is the worst outcome

o Only can be solved with more antibiotics but these create adverse effects that do not help patient

o low survival rate once drug-resistant TB develops

Prevention

• bacillus Calmette–Guérin (BCG) o usually only administered to high-risk populations

because it becomes ineffective after 10 years and can produce false positives on the skin test.

• The drug isoniazid prevents most detected tuberculosis infections from developing into the disease.o often prescribed to those with a positive skin test.

• An ultraviolet overhead light is often used to help prevent the disease from spreading o used in hospitals and other places where patients

come into contact with uninfected people

Citations

• The CDC. "Tuberculosis (TB)." Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 12 Apr. 2013. Web. 14 May 2013. <http://www.cdc.gov/tb>.

• Levitzky, Michael G. "Tuberculosis." World Book Student. World Book, 2013. Web. 15 May 2013.

• Stephan Schwander and Keertan Dheda "Human Lung Immunity against Mycobacterium tuberculosis", American Journal of Respiratory and Critical Care Medicine, Vol. 183, No. 6 (2011), pp. 696-707.