Classification and prophylactics of tuberculosis

Presentation by,

Al auf Jalaludeen

TUBERCULOSIS

Tuberculosis,TB  also called phthisis, phthisis

pulmonalis, or consumption, is a widespread,

and in many cases fatal, infectious disease

 caused by various strains of mycobacteria,

usually Mycobacterium tuberculosis.

Tuberculosis typically attacks the lungs, but

can also affect other parts of the body.

Mode of infection

 It is spread through the air when people who have

an active TB infection cough, sneeze, or otherwise

transmit respiratory fluids through the air. Most

infections do not have symptoms, known as latent

tuberculosis. About one in ten latent infections

eventually progresses to active disease which, if

left untreated, kills more than 50% of those so

infected.

When people with active pulmonary TB cough,

sneeze, speak, sing, or spit, they expel

infectious aerosol droplets 0.5 to 5.0 µm in

diameter. A single sneeze can release up to

40,000 droplets. Each one of these droplets

may transmit the disease, since the infectious

dose of tuberculosis is very small (the

inhalation of fewer than 10 bacteria may

cause an infection)

Types of TBTuberculosis is divided into two categories: pulmonary and extrapulmonary.

Pulmonary Tuberculosis Types:

Primary Tuberculosis Pneumonia Tuberculosis Pleurisy Cavitary Tuberculosis Miliary TB Laryngeal Tuberculosis

Primary Tuberculosis Pneumonia

This uncommon type of TB presents as pneumonia

and is very infectious. Patients have a high fever

and productive cough. It occurs most often in

extremely young children and the elderly. It is also

seen in patients with immunosuppression, such as

people with HIV/AIDS, and in patients on long term

corticosteroid therapy.

Tuberculosis Pleurisy

This usually develops soon after initial infection. A granuloma

located at the edge of the lung ruptures into the pleural space,

the space between the lungs and the chest wall. Usually, a couple

of tablespoons of fluid can be found in the pleural space.

Once the bacteria invade the space, the amount of fluid increases

dramatically and compresses the lung, causing shortness of

breath (dyspnea) and sharp chest pain that worsens with a deep

breath (pleurisy). A chest x-ray shows significant amounts of fluid.

Mild- or low-grade fever commonly is present. Tuberculosis

pleurisy generally resolves without treatment; however, two-

thirds of patients with tuberculosis pleurisy develop active

pulmonary TB within 5 years.

Cavitary TB

Cavitary TB involves the upper lobes of the lung. The bacteria

cause progressive lung destruction by forming cavities, or

enlarged air spaces. This type of TB occurs in reactivation disease.

The upper lobes of the lung are affected because they are highly

oxygenated (an environment in which M. tuberculosis thrives).

Cavitary TB can, rarely, occur soon after primary infection.

Symptoms include productive cough, night sweats, fever, weight

loss, and weakness. There may be hemoptysis (coughing up

blood). Patients with cavitary TB are highly contagious.

Occasionally, disease spreads into the pleural space and causes TB

empyema (pus in the pleural fluid).

Miliary TB

Miliary TB is disseminated TB. "Miliary" describes the appearance

on chest x-ray of very small nodules throughout the lungs that

look like millet seeds. Miliary TB can occur shortly after primary

infection. The patient becomes acutely ill with high fever and is in

danger of dying. The disease also may lead to chronic illness and

slow decline.

Symptoms may include fever, night sweats, and weight loss. It can

be difficult to diagnose because the initial chest x-ray may be

normal. Patients who are immunosuppressed and children who

have been exposed to the bacteria are at high risk for developing

miliary TB.

Laryngeal TB

TB can infect the larynx, or the vocal chord area. It is extremely infectious.

Extrapulmonary Tuberculosis This type of tuberculosis occurs primarily in immunocompromised patients. Lymph Node Disease Tuberculosis Peritonitis Tuberculosis Pericarditis Osteal Tuberculosis Renal Tuberculosis Adrenal Tuberculosis Tuberculosis Meningitis

Lymph Node Disease

Lymph nodes contain macrophages that capture the

bacteria. Any lymph node can harbor uncontrolled

replication of bacteria, causing the lymph node to become

enlarged. The infection can develop a fistula (passageway)

from the lymph node to the skin.

Tuberculosis Peritonitis

M. tuberculosis can involve the outer linings of the

intestines and the linings inside the abdominal wall,

producing increased fluid, as in tuberculosis pleuritis.

Increased fluid leads to abdominal distention and pain.

Patients are moderately ill and have fever.

Tuberculosis Pericarditis The membrane surrounding the heart (the pericardium) is affected

in this condition. This causes the space between the pericardium

and the heart to fill with fluid, impeding the heart's ability to fill

with blood and beat efficiently.

Osteal Tuberculosis Infection of any bone can occur, but one of the most common sites

is the spine. Spinal infection can lead to compression fractures and

deformity of the back.

Renal Tuberculosis This can cause asymptomatic pyuria (white blood cells in the urine)

and can spread to the reproductive organs and affect reproduction.

In men, epididymitis (inflammation of the epididymis) may occur.

Adrenal Tuberculosis TB of the adrenal glands can lead to adrenal

insufficiency. Adrenal insufficiency is the inability to increase steroid production in times of stress, causing weakness and collapse.

TB Meningitis M. tuberculosis can infect the meninges (the

mainmembrane surrounding the brain and spinal cord). This can be devastating, leading to permanent impairment and death. TB can be difficult to discern from a brain tumor because it may present as a focal mass in the brain with focal neurological signs.

Headache, sleepiness, and coma are typical symptoms. The patient may appear to have had a stroke.

Signs and symptoms

Tuberculosis may infect any part of the body, but

most commonly occurs in the lungs (known as

pulmonary tuberculosis). Extrapulmonary TB occurs

when tuberculosis develops outside of the lungs,

although extrapulmonary TB may coexist with

pulmonary TB, as well.

General signs and symptoms include fever, chills, 

night sweats, loss of appetite, weight loss, and 

fatigue. Significant nail clubbing may also occur.

Causes The main cause of TB is Mycobacterium tuberculosis, a

small, aerobic, nonmotile bacillus.[10] The high lipid

 content of this pathogen accounts for many of its

unique clinical characteristics.[19] It divides every 16 to

20 hours, which is an extremely slow rate compared

with other bacteria, which usually divide in less than an

hour.[20] Mycobacteria have an outer membrane lipid

bilayer.

 MTB can withstand weak disinfectants and survive in

a dry state for weeks. In nature, the bacterium can

grow only within the cells of a host organism, but M.

tuberculosis can be cultured in the laboratory

Methods of prophylaxis Stopping the Spread of Tuberculosis

Anyone who comes into contact with an individual infected with tuberculosis

bacteria is at risk of developing the disease, so one obvious solution is

to steer clear of people who are sick, sneezing, and coughing. Follow these

additional steps to help prevent the spread of tuberculosis infection:

People with tuberculosis infection should always cover their mouths

when they cough or noses when they sneeze.

People with latent tuberculosis infection — when there are no symptoms

 or active disease — should take medication to prevent it from becoming

active tuberculosis disease.

People with TB should take all medications as required.

People at risk for or who have been in contact with people with

tuberculosis infection should be tested.

The TB Vaccine

The vaccine, developed nearly 100 years ago, is called BCG (bacille

Calmette-Guérin). It is made from weakened tuberculosis bacteria

that infect cows, similar to the human form of tuberculosis.

The vaccine works against a severe type of TB that affects young

children, but it is not effective against the type of bacteria found in

adults. That severe type of tuberculosis, called military TB , is rare

in the United States, so the vaccine isn’t used on young children

here.

Children who live with someone infected with TB may be eligible to

receive the vaccine if they would not be able to tolerate the

antibiotic treatment or if the type of TB is antibiotic-resistant.

TB Testing

Anyone who has been or may have been exposed to tuberculosis

should be tested for it right away. The sooner TB is diagnosed,

the sooner treatment can begin — and the easier it is to prevent

both its spread and serious complications.

A simple skin test, known as the PPD (purified protein

derivative) TB skin test or tuberculin skin test, is given to check

for the presence of the bacteria that cause tuberculosis. A

chemical is injected just beneath the skin surface, and within 48

to 72 hours the skin is examined for any reaction. Swelling may

indicate a positive test result.

Tuberculosis Medication

Medications are available to treat active tuberculosis,

as well as to prevent latent tuberculosis infection from

developing into the actual disease. Isoniazid (INH), for

instance, is a drug prescribed for those with latent

tuberculosis infection.

Medications must be started right away to control the

disease and keep it from infecting other people. They

are typically taken several times a day for at least six

months, and sometimes up to a year.

Protect your family and friends

If you have active TB, keep your germs to yourself. It generally takes a few

weeks of treatment with TB medications before you're not contagious anymore.

Follow these tips to help keep your friends and family from getting sick:

Stay home. Don't go to work or school or sleep in a room with other people

during the first few weeks of treatment for active tuberculosis.

Ventilate the room. Tuberculosis germs spread more easily in small closed

spaces where air doesn't move. If it's not too cold outdoors, open the

windows and use a fan to blow indoor air outside.

Cover your mouth. Use a tissue to cover your mouth anytime you laugh,

sneeze or cough. Put the dirty tissue in a bag, seal it and throw it away.

Wear a mask. Wearing a surgical mask when you're around other people

during the first three weeks of treatment may help lessen the risk of

transmission.