Classification and prophylactics of tuberculosis

Classification and prophylactics of tuberculosis

1. Presentation by, Al auf Jalaludeen TUBERCULOSIS

2. 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.

3. 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.

4. 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)

5. Types of TB Tuberculosis is divided into two categories :  pulmonary  and  extrapulmonary . Pulmonary Tuberculosis Types: Primary Tuberculosis Pneumonia Tuberculosis Pleurisy Cavitary Tuberculosis Miliary TB Laryngeal Tuberculosis

6. 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.

7. 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.

8. 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).

9. 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.

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

11. 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

12. 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.

13. 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.

14. 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.

15. 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.

16. 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

17. 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.

18. 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.

19. 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.

20. 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.

21. 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.