Outline Transmission Mycobacteria Pathogenesis LTBI LTBI vs TB Disease Symptoms of TB Disease Factors which increase the Risk of Developing TB Disease.

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Outline Transmission Mycobacteria Pathogenesis LTBI LTBI vs TB Disease Symptoms of TB Disease Factors which increase the Risk of Developing TB Disease Sites of TB Disease Treatment of TB Disease Medications Drug Resistant TB Slide 2 2 A.Brief History of TB Afflicted mankind since ancient times. Evidence of TB found in Egyptian and Peruvian mummies. In the 19 th century, the disease was often referred to as consumption. Other names wasting disease, White Plague. Slide 3 3 Tuberculosis remains a Global Concern Among infectious diseases, TB remains the second leading killer of adults in the world, with more than two (2) million TB related deaths per year. It is estimated that 1 in 3 people on earth are infected with the TB bacillus. Developing countries have the highest rates of TB. The incidence rate of tuberculosis in Canada is considered low (5.1 per 100,000), especially in the global context. The highest incidence rates of TB in Canada are reported among Canadian-born Aboriginal peoples. There are wide fluctuations even among this group. In Ontario, rates are much lower among First Nations reserves than in Manitoba, Saskatchewan and the far north. Slide 4 4 The history of TB in First Nations is a very painful and sad one. For many people a diagnosis of TB was a death sentence. Deaths resulting from TB in the early 20 th century were at an estimated 42.6 per 1000 in the Indian population in western Canada. Some First Nations people with TB were sent to sanatoria far from their communities. Many did not return for years and some felt like strangers in their community and family. Some patients died in the sanatorium and families never saw them again. It is understandable that First Nations people who remember this have very negative feelings about TB. Fort William Sanatorium History of TB in First Nations Slide 5 Elders andTB Stories Slide 6 Elders tell their stories Slide 7 TB is spread from person to person through the air. The dots in the air represent droplet nuclei containing tubercle bacilli. Slide 8 8 What is Tuberculosis? TB is a disease caused by an organism called Mycobacterium tuberculosis, a member of the bacteria family. Slide 9 Pathogenesis ( the mechanism that causes the disease) of Tuberculosis Slide 10 10 How does TB enter the body? Droplet nuclei containing tubercle bacilli are inhaled, enter the lungs, and travel to the alveoli. Slide 11 11 Infection begins when droplet nuclei reach the alveoli. Slide 12 12 A small number of tubercle bacilli enter the bloodstream and spread throughout the body. The tubercle bacilli may reach any part of the body, including areas where TB disease is more likely to develop (such as the lungs, kidney, brain, or bone). Slide 13 13 Within 2 to 8 weeks the immune system produces immune cells called macrophanges that surround the tubercle bacilli. The cells form a barrier shell that keeps the bacilli contained and under control. This is known as Latent TB Infection (LTBI). Slide 14 Latent TB Infection ( LTBI) Latent TB infection (LTBI) means that tubercle bacilli are in the body, but the bodys immune system is keeping the bacilli under control and inactive. The immune system does this by producing special immune cells that surround the tubercle bacilli. The cells form a shell that acts as a fence and keep the bacilli contained and inactive. Slide 15 15 If the immune system cannot keep the tubercle bacilli under control, the bacilli begin to multiply. This is TB disease. This process can occur in different places in the body such as the lungs, kidneys, brain, or bone. Slide 16 LTBI TB Disease Latent TB Infection ( LTBI) Tuberculin skin test results usually positive Chest xray usually normal Sputum smears and cultures negative No symptoms Not infectious Not a case of TB TB disease in the lungs Active tubercle bacilli in the body Tuberculin skin text results usually positive Chest x-ray usually abnormal Sputum smears and cultures may be positive Symptoms such as cough, fever, weight loss Often infectious before treatment A case of TB Slide 17 Symptoms of TB disease Cough for more than 3 weeks. Extreme tiredness Fever No appetite Weight loss Sweating at night Slide 18 TB is not easy to catch! You generally have to spend a lot of time with a person coughing or sneezing germs at home, work, or school in order for you to catch TB germs. The disease spreads most easily in closed dwellings with little sunlight and poor air circulation. Slide 19 These four factors influence the probability that TB will be transmitted. Slide 20 Conditions that increase the risk of developing TB disease. Infection with HIV Chest x-ray findings suggestive of previous TB Substance abuse ( especially illegal injection drug use) Recent TB infection ( within the past 2 years) Prolonged therapy with corticosteroids and other immunosuppressive therapy such as prednisone Organ transplant Silicosis Diabetes Mellitus Severe kidney disease Certain types of cancer Certain intestinal conditions Low body weight ( 10% or more below ideal) Slide 21 Risk of Developing TB Disease Slide 22 Sites of TB Disease Pulmonary TB TB that occurs in the lungs. Most cases of TB are pulmonary. Patients usually have a cough and an abnormal chest x-ray Extrapulmonary TB- occurs in places other than the lungs such as the larynx, the lymph nodes, the pleura ( the membrance surrounding each lung), the brain, the kidneys, or the bones and joints. Miliary TB- occurs when tubercle bacilli enter the bloodstream and are carried to all parts of the body where they grow and cause disease in multiple sites. Chest xray has the appearance of millet seeds scattered throughout the lung Slide 23 Remember: Only pulmonary/laryngeal TB is contagious and can be spread to others. Slide 24 QUIZ 1) A person with TB infection can spread TB germs to others. T F 2) People with TB disease lose weight. T F 3) TB Infection is when the TB germs are sleeping in your body and not making you sick. T F 4) Once a person catches TB germs, they will have them all their lives. T F 5)You will feel weak and tired all the time if you have TB Disease. T F 6) TB is only found in the lungs. T F 7)TB can be cured. T F 8)TB disease is when the TB germs start growing and making the person sick. T F 9) TB germs can be spread through the air from one person to another. T F Slide 25 25 The good news now is there is a cure for TB!! Slide 26 Treatment of TB Disease TB disease must be treated for at least 6 months Most of the tubercle bacilli are killed during the first 8 weeks of treatment ( the initial phase) Treatment with at least two drugs must be continued for several more months to kill the remaining bacilli (the continuation phase) Slide 27 Medications The initial regimen for treating active TB disease should include the following four drugs: Isoniazid Rifampin Pyrazinamide Ethambutol TB disease must be treated with at least two drugs to which the bacilli are susceptible Slide 28 Drug- resistant TB Slide 29 Can be caused in two different ways: Primary caused by person-to-person transmission of drug-resistant organisms Secondary develops during TB treatment, either because the patient was not treated with the appropriate treatment regimen or because the patient did not follow the treatment regimen as prescribed Slide 30 How does drug resistant TB develop? Patient does not take their medicine regularly. Patient does not take all of their medicine, as told by their health care provider Patient develops active TB disease again, after having taken TB medicine in the past Patient comes from area of the world where drug- resistant TB is common Slide 31 DOT- Directly Observed Therapy Directly observed therapy means that a health care provider administers the medication to the client Assists the client to consistently take their medication until completion. Slide 32 32 E.Treatment of TB Disease Untreated TB carries a high mortality rate More than one drug is required for cure Usual regimen for uncomplicated TB: 4 drugs x 2 months 2 drugs x 4 months In consultation with a TB specialist, drug therapy may continue for 9, 12, or more months. Poor compliance leads to relapse and drug resistance. Directly Observed Therapy (DOT) is the gold standard world-wide. Even with perfect compliance a small % will relapse. Slide 33 Review Questions What organism causes TB? How is TB spread? The probability that TB will be transmitted depends on what four factors? What is drug-resistant TB? What is the difference between primary and secondary drug-resistant TB? Slide 34 REMEMBER: If you need more information about TB, contact the Tuberculosis (TB) Control Program (807) 737-4797 Toll Free: 1-855-885-8824