6.Tb final presentation Year 4 Internal Medicine Notes

6.Tb final presentation Year 4 · Internal Medicine Collection: 4TH YEAR ALL NOTES / IMED / IMED 4.1 / NGUGI -- Slide 1 PULMONARY TUBERCULOSIS Presented by: 1.DENNIS MURIRA 2.LINAH AMBIA 3.YVONNE MURIITHI 4.WESLEY ONYIEGO 5.ELIUD KARANJA Slide 2 AETIOLOGY Tuberculosis is caused by the bacterium Mycobacterium tuberculosis (M. tuberculosis). M. tuberculosis and seven very closely related mycobacterial species (M. bovis, M. africanum, M. microti, M. caprae, M. pinnipedii, M. canetti and M. mungi) together comprise what is known as the M. tuberculosis complex. Slide 3 The agent: Mycobacteria sp. Actinobacteria (Phylum), family Mycobacteriaceae Genus Mycobacteria Species are described in several major groups for purpose of diagnosis and treatment: M. tuberculosis, M. bovis, M. africanum, and M. microti; – M. leprae which causes Hansen’s disease or leprosy; – Nontuberculous mycobacteria (NTM) are all the other mycobacteria which can cause pulmonary disease resembling tuberculosis, lymphadenitis, skin disease, or disseminated disease. Slide 4 Global burden 22 countries have 80% of TB cases today Slide 5 Kenya is among high TB burden countries Slide 6 Transmission M. tuberculosis is transmitted through airborne infectious droplet nuclei which are generated when persons who have pulmonary or laryngeal TB disease cough, sneeze, shout, or sing.\nThese tiny particles (1– 5 microns in diameter) can remain suspended in the air for several hours.\nTransmission occurs when a person inhales droplet nuclei containing M. tuberculosis, and the droplet nuclei traverse the mouth or nasal passages, upper respiratory tract, and bronchi to reach the alveoli of the lungs. Slide 7 FACTORS INCREASING THE RISK OF TB Patient related 1.Age-Children are more susceptible to infection than young adults.Elderly people are more susceptible to infection than children and young adults. 2.Overcrowding-in places such as schools, prisons,market places,hostels 3.Close contact with patients with smear positive pulmonary TB 4.Chest X-ray evidence of self healed TB 5.Smoking-cigarettes 6.Primary TB infection in less than a year. Slide 8 Associated disease 1.Immunosuppresion-Infections such as HIV,antitumor necrosis factor 2. Chronic Kidney disease 3.Deficiency of vitaminD and A 4.Recent measles infection in children 5.Silicosis. 6.Diabetes mellitus. 7.Malignancy-Especially lymphomas and leukaemia. 8.Gastrointestinal disease associated with malnutrition such as cancer of the pancreas, gastrectomy,malabsorption. Slide 9 Pathogenesis M.tuberculosis is spread by inhalation of aerolised droplet nuclei from other infected patients The bacilli lodge in the alveoli and recruit macrophages and lymphocytes. macrophages transform into epitheliod and langerhan cells which aggregate with lymphocytes to form a classical tuberculous granuloma Numerous granuloma aggregate to form primary lesion "Ghon focus" which is characteristically situated at the periphery of lung Spread of organisms to hilar lymph nodes forming primary lesion of ranke Slide 10 reparative process encase the primary complex in a primary capsule limiting the spread of bacilli "latent TB" If no further compilation happens the lesion calcifies and can be seen in a chest radiograph Lymphatic or hematogenous spread may occur before immunity is established seeding secondary foci in other organs including lymph nodes serous membranes meninges bones liver kidney lungs which may lie dormant for years If reparative process fails primary progressive disease ensues Slide 12 HIV infection Age especially those under the age of two years\nRecent infection with M. tuberculosis (within the last two years) History of previously poorly treated TB Immunosuppressive therapy Other immune suppressive conditions e.g. diabetes, silicosis, malignancies Risk factors for progression of latent Tb to active TB Slide 13 Classification based on anatomical sites\nPulmonary TB (PTB-This is TB disease involving the lung parenchyma (segmental or lobar consolidation, TB bronchopneumonia).\nMilliary TB is disseminated disease but classified as PTB because there are lesions in the lungs.\nExtra pulmonary TB (EPTB)-This is TB disease present outside the lung parenchyma. Intra-thoracic (Inside the chest, but outside the lung tissue): pleural effusion, intra-thoracic lymphadenopathy, (mediastinal, paratracheal or hilar lymphadenopathy) Extra-thoracic (Outside the chest): Peripheral Lymph nodes, abdomen, genitourinary tract, skin, joints and bones, meninges.\nA patient with both pulmonary and extra pulmonary TB should be classified as a case of PTB. CLASSIFICATION OF TUBERCULOSIS Slide 14 Classification based on history of previous TB treatment (patient registration group)\nNew patients-Patient who has never been treated for TB or has taken anti-TB drugs for less than one month.\nPreviously treated patients-Patient who has received 1 month or more of anti-TB drugs in the past. They are further classified by the outcome of their most recent