TB Year 4 Internal Medicine Notes OmpathStudy

TB Year 4 · Internal Medicine Collection: 4TH YEAR ALL NOTES / IMED / I MED BEAUTIFUL NOTES / HEMAT -- TUBERCULOSIS\n435 medicine teamwork 435 medicine teamwork [ Important Notes Extra Editing file ]\n\n lecture objectives:\n⇨ Overview of tuberculosis (TB) epidemiology\n⇨ Transmission and TB pathogenesis\n⇨ Clinical presentation\n⇨ Testing for TB infecting diseases\n⇨ Diagnosis of TB disease\n⇨ Treatment of latent TB\n⇨ Treatment of TB Diseases\n⇨ TB infection control\n\n Done By: Ola AlNuhayer\nEdited by:Rahaf Binabbad\nRevised By: Rahaf Binabbad & Luluh Alzeghayer\nReferences: Doctors’ Slides + Davidson \n\n Epidemiology + Transmission General characteristics of TB:\nWhat is it:Tuberculosis is a bacterial infection caused by Mycobacterium tuberculosis (also called\ntubercle bacillus). It damages a person’s lungs or other parts of the body. It is fatal if not treated properly. \nTB epidemiology:\n● It is a worldwide disease\n● 90% of cases and 95% of death occurred in developing countries.\n● Number of cases in developed countries has declined because of: case finding & treatment &\nImproved Nutrition.\nTuberculous infection & tuberculous disease:\n\n Notes\n- In saudi Arabia there is 25 - 49 new cases per\n100,000\n- there are a lot of areas (red / dark red) with high\nincidence of TB (india, pakistan, south east asia,\nsouth africa...). Anyone from these countries can\ncome to us for hajj or just for work!!\n- In history-taking, it is important to ask about\nnationality, residency, and travel history \n● 10% of infected people →develop active disease\n● 50% of active disease → are contagious (not all TB cases are contagious. Open pulmonary TB is the\nmost contagious type and laryngeal TB is the second most contagious type)\n\n What increases the spread of the disease?\n1. Crowding of living -prisons, schools..etc-. it is important to ask about the work, and whether the\npatient lives alone or with roommates in social history\n2. Migration of people from endemic area.\nWhat increases the risk of developing disease after TB infection?\n1. Infecting dose\n2. Host factors\n○ Age: under 5 years, elderly\n○ Debilitating illness and poor nutrition\n○ Alcoholism\n○ Long-term use of steroid\n○ Gastrectomy (it can cause poor nutritional status and an associated reduction in immunity /\nAcid-protective property is lost. Don’t forget to ask about it in past surgical history!!)\n○ Diabetes mellitus Mode of spread and transmission:\n● Mycobacterium tuberculosis spread via airborne particles called droplet nuclei (aerosoles)\n“Airborne spread happens when a germ floats through the air after a person talks, coughs, or\nsneezes” what type of isolation should be carried to a patient with ACTIVE TB? AIRBORNE isolation\nwith NEGATIVE pressure room. (NOT droplet isolation!) \n\n ● Theses droplet nuclei are expelled when person with infectious TB (active TB): Coughs, Speaks,\nLaughs, Sneezes, or Sings\n● Transmission occurs when droplet nuclei inhaled and reach the alveoli of the lungs, via nasal\npassages, respiratory tract, and bronchi \nPathogenesis\n● Droplet nuclei → terminal air space → Multiplication → initial focus\n○ the initial focus is usually Subpleural & in 75% it is single\n● Migration through blood and lymph node → another focus\n● Ingestion of the bacteria by the macrophage → slow multiplication (that’s why we treat for 6 months) Pathogenesis: \n1 2 3 4 5\n\nExposure to the Tubercle bacilli TB bacilli infect the alveoli If the immune system cannot A small number of tubercle source (coughing multiply in the and the body immune system keep the tubercle bacilli bacilli may enter the person infected alveoli. begins to fight them. under control, the bloodstream and spread with TB) bacilli begin to multiply throughout the body. The inhalation of The majority of Within 2 to 8 weeks, special rapidly (TB disease). tubercle bacilli may reach droplet nuclei infected individuals immune cells called macrophages any part of the body, (aerosols) their immune system ingest and surround the tubercle As more lung tissue is including areas where TB\ncontrols the infection\nbacilli. The cells form a barrier destroyed and granulomas disease is more likely to\nand this is the end of\nshell, called a granuloma, where expand, cavities develop in develop (such as the brain,\nthe story! the infection At this stage 50% remains latent the rest bacilli not killed BUT not the lungs, which causes more larynx, lymph node, lung, will not get the of their lives without multiplying. (LTBI). coughing and shortness of spine, bone, or kidney). infection, the causing any symptoms! 🌟 “Granuloma is NOT diagnostic breath. Granulomas can also other < 50% will of TB since many other diseases eat away blood vessels which acquire the the unlucky 10%-5% manifest granulomas” (sometimes causes bleeding in the lungs, infection as will go on developing TB spreads through direct and bloody sputum. bacteria reaches TB disease. (mostly extension: vertebral TB\ns