Tb

364 views
239 views

Published on

Published in: Education
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
364
On SlideShare
0
From Embeds
0
Number of Embeds
5
Actions
Shares
0
Downloads
8
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide
  • * AIDS is the first cause of death due to infectious diseases
  • *TB is more commonly spread by repeated close contact* with infected person.
    Within 6 inches of the person's mouth
  • 2. Small paces with limited ventilation would mean higher concentration. ( small room Vs big hall).
  • The epiphysis is the rounded end of a long bone, at its joint with adjacent bone(s).
  • Certain individuals are at a higher risk of active disease (immuno-suppressed, or DM), there Is a good chance that they will develop into active TB, hint: why treatment in such conditions is prescribed
    Reactivation of the LTBI can occur if the host’s defense mechanism become impaired such as decreased resistance found in older adult.
  • a yellow-greenish (mucopurulent)
    a white, milky, or opaque (mucoid)
    HIV infected people: atypical physical exam and CXR; fever, cough, weight loss attributed to pneummocystis jiroveci pneumonia (PCP), or due to any other opportunistic diseases. Also cancer patients and any Immunocompromised patients, may suffer from opportunistic diseases , and any respiratory manifestations should be investigated immediately for those group of patients.
    An opportunistic infection is an infection caused by particularly opportunistic pathogens—those that take advantage of certain situations. usually do not cause disease in a healthy host, one with a healthy immune system. A compromised immune system, however, presents an "opportunity" for the pathogen to infect.
  • Purified protein derivative
    **this x ray can be seen in other disease as well, so an Xray alone is not enough to confirm TB diagnosis
    3-consecutive specimen can be collected on different days, sent for smear and culture( it can take up to 8 weeks for confirmative results of growth).
  • *triggering an inflammatory reaction, producing exudates (Protein rich fluid).
    Empyema can occur form larger number of tubercular organisms in pleura.
    3- resulting form TB discharged from granulomas into lungs and lymph nodes
  • * We do one as baseline when we start the treatment, and continue to do it once every month for monitoring purposes
  • Mycobacterium bovis is a slow-growing (16 to 20 hour generation time), aerobic bacterium and the causative agent of tuberculosis in cattle (Cow) .
  • Tb

    1. 1. Tuberculosis review study by master degree student Bashar M. Khazaal
    2. 2. Objectives: • What are Tuberculosis??. • What are the risk factors, etiology, pathophysiology and clinical manifestations of TB ??. • What are the diagnostic methods for TB ??. • What are the complications and management of TB ??. • What are Multi drug resistance TB ??.
    3. 3. Tuberculosis • It is an infectious disease caused by mycobacterium tuberculosis. • Usually involves the lungs, but can involve other body parts. • Very common cause of death from infectious diseases in the world.
    4. 4. Tuberculosis Risk factors :      Immuno-suppressed patients (e.g., HIV, Long term Corticosteroids use) Older adult in long term facilities ( e.g. jails, elderly homes) IV injecting drug users Persons at poverty level, with poor access to health care services, homeless. Health care workers in increased exposure to TB.
    5. 5. TB: Pathophysiology • M. tuberculosis is a gram-positive, acid-fast bacillus. • It spreads from person to person via airborne droplets produced while talking or coughing. • Brief exposure to tubercle bacilli rarely causes infection. • TB is not usually highly infectious, transmission requires frequent, close, or prolonged exposure
    6. 6. Tuberculosis: Pathophysiology • • The very small droplets (1-5 µm) contain M. tuberculosis, remains airborne indoors from minutes to hours. When inhaled; they are lodged into the bronchioles and alveolus. • Factors that influence the likelihood of transmission 1. 2. 3. 4. Number of organisms expelled into air Concentration of organisms. Length of time of exposure Immune system of the exposed person
    7. 7. Tuberculosis: Pathophysiology • • - M. tuberculosis replicates slowly over time. It travels through lymphatic system to find a suitable environment for growth primarily in the: Upper lobes of the lungs Kidneys Epiphyses of the bones Cerebral cortex Adrenal glands
    8. 8. Tuberculosis: classifications Latent TB: the bacteria is inhaled , but there is an active immune system, the bacteria will be capsulated for life, and become inactive, preventing the disease to progress, so they are not sick or showing any symptoms, and they cannot spread the germs. Active TB: if the initial response of the immune system was not adequate, the body can not maintain control of the organism, and it develops into infection, so active bacteria are multiplying and causing clinical active disease.
    9. 9. Tuberculosis: clinical manifestation • Latent TB: usually asymptomatic, but have a positive TST. • Active TB: fatigue, malaise, anorexia, unexplained weight loss, low-grade fevers, and night sweats. • Frequent cough, produce mucoid or mucopurulent sputum • Hemoptysis is usually seen with more advanced cases. • Dyspnea is unusual • Acute exacerbations: high fever, chills, general flu-like symptoms pleurisy pain and productive cough.
    10. 10. Tuberculosis: Diagnostic studies 1. Tuberculin skin test (TST): Mantoux test: PPD 0.1 ml is injected ID on the dorsal aspect of the forearm, and then read by inspection palpation after 48-72 hour, for presence or absence of indurations 2. Chest X-ray: presence of upper lob infiltrates, & lymph nodes involvements ( but can not be confirmative alone for TB) 3. Bacteriologic and other studies : microscopic examination of stained sputum smear of acid-fast bacillus( AFB testing). - Other samples of suspected infected sites can be taken as well. e.g.: gastric wash, CSF sample, fluids from an effusion. Löwenstein‒Jensen medium culturing.
    11. 11. Table 1. Components of Löwenstein‒Jensen medium Components measures 2.4 g Monopotassium dihydrophosphate (KH2PO4), anhydrous Magnesium sulfate (MgSO4 ·7H2O) Magnesium citrate L-Asparagine Distilled water up to Glycerol (ml) or pyruvatea (g) Egg homogenate Malachite green (2%) pH (about) 0.24 g 0.6 g 3.6 g 600 ml 12 ml or 7.2 g 1000 ml 20 ml 6.8
    12. 12. Drug susceptibility testing Drug susceptibility testing means testing to find out which drugs the TB bacteria in a person are sensitive to, and therefore whether the person has got drug resistant TB. It is essential that if a person might possibly have drug resistant TB, that this is discovered as soon as possible, in order that the patient can be provided with effective TB treatment. Historically drug susceptibility testing has needed specific laboratory facilities and trained personnel, and in addition has been a very lengthy process.
    13. 13. Different types of drug susceptibility tests • Phenotypic drug susceptibility tests Conventionally TB drug susceptibility testing has been phenotypic, involving the culturing of M. tuberculosis in the presence of anti TB drugs in order to detect growth (indicating drug resistance) or inhibition of drug (indicating drug susceptibility).
    14. 14. • Molecular methods of drug susceptibility testing Since resistance arises from genetic mutations, another approach is to detect the mutations themselves. Many mutations associated with resistance have been identified and molecular tests to detect them have been developed. The advantages of molecular methods of drug susceptibility testing include rapid turnaround times, but the disadvantages include a low sensitivity for some compounds, and a major issue is cost.
    15. 15. 4. QuantiFERON-TB •Originally developed in Australia to test cattle for M. bovis infection •Measures IFN-γ in stimulated whole blood. •1st generation used purified protein derivative (PPD) •2nd generation (QFT-Gold) uses ESAT-6 and CFP-10 •3rd generation (QFT-Gold in tube) uses ESAT-6, CFP-10 and TB 7.7
    16. 16. • How does QuantiFERON-TB Gold In-Tube work? The QFT-G is an indirect test for M. tuberculosis infection that is based on measurement of a cell-mediated immune response. A cocktail of 3 mycobacterial proteins (ESAT-6, CFP-10, and TB 7.7) stimulate the patient's T-cells in vitro to release interferon-gamma, which is then measured using ELISA technology.
    17. 17. BCG strains and the majority of other non-tuberculosis mycobacteria do not harbor ESAT-6, CFP-10, and TB 7.7 proteins; thus, patients either vaccinated with BCG or infected with most environmental mycobacteria should test negative.
    18. 18. 5. T – spot TB test measure a person’s immune reactivity to M. tuberculosis. White blood cells from most persons that have been infected with M. tuberculosis will release interferon-gamma (IFN-g) when mixed with antigens (substances that can produce an immune response) derived from M. tuberculosis. To conduct the tests, fresh blood samples are mixed with antigens and controls. The antigens, testing methods, and interpretation criteria for QuantiFERON-TB differ (see Table 2).
    19. 19. Table2: Differences in Currently Available QuantiFERON-TB QuantiFERON-TB Initial Process T-Spot Process whole blood Process peripheral blood within 16 hours mononuclear cells (PBMCs) within 8 hours. M. tuberculosis Antigen Single mixture of Separate mixtures of synthetic synthetic peptides peptides representing ESAT-6 & CFPrepresenting ESAT-6, 10 CFP-10 & TB7.7. Measurement IFN-g concentration Number of IFN-g producing cells (spots) Possible Results Positive, negative, indeterminate Positive, negative, indeterminate, borderline
    20. 20. 6. PCR Other mycobacteria are also acid-fast. If the smear is positive, PCR or gene probe tests can distinguish M. tuberculosis from other mycobacteria.
    21. 21. Tuberculosis: complications 1. Miliary TB: M.O can invade blood stream, & involve many organs. it can be due to a primary disease, or activation of LTB. patient either acutely ill with fever, dyspnea and cyanosis, or chronically ill with weight loss, fever, GI manifestations; hepatomegally , spleenomegally. 2. Pleural effusion & Empyema: effusion is caused by bacteria in the pleural space. Empyema is less common. 3. Tuberculosis pneumonia: acute pneumonia 4. Other organ involvement: CNS; with inflammation of the meninges, joints, bone, kidneys adrenal glands, LN, and
    22. 22. Tuberculosis: management • Most patients can be treated on outpatient basis • Hospitalization maybe needed for the severely ill patients • Mainstay (basis) is drug therapy • Monitoring for complications is a key for successful treatment
    23. 23. Tuberculosis: drug therapy • Initial phase treatment: 4 drugs for 6 months ( isoniazid, rifampin, pyrazinamide, and ethambutol). • Nursing consideration: pregnancy, liver damage, and alcoholism should be kept under monitoring. • DOT( directly observed therapy): is a new approach to observe patients taking their medications, especially useful for patients who might be having compliance problems.
    24. 24. Tuberculosis: drug therapy • In LTBI: drug therapy can be initiated to prevent it from becoming active TB. • Usually treatment is less expensive and of less duration if started as preventive measure. • In general it is isoniazid, and can be administered once daily from 6-9 months .
    25. 25. WHAT ARE MDR-TB, XDR-TB AND RR-TB ? TB organisms resistant to the antibiotics used in its treatment are widespread and occur in all countries surveyed. Drug resistance emerges as a result of inadequate treatment and once TB organisms acquire resistance they can spread from person to person in the same way as drug-sensitive TB. • Multidrug-resistant TB (MDR-TB) is caused by organisms that are resistant to at least the two most effective anti-TB drugs, isoniazid and rifampicin. • Extensively drug-resistant TB (XDR-TB) is a form of TB caused by organisms that are resistant to isoniazid and rifampicin (i.e. MDR-TB) as well as any fluoroquinolone and any of the second–line anti-TB injectable drugs (amikacin, kanamycin or capreomycin). • Rifampicin-resistant TB (RR-TB) is caused by organisms that are resistant to rifampicin, with or without resistance to other drugs. Both MDR-TB and XDR-TB are forms of RR-TB. • These forms of TB do not respond to the standard six month treatment with first-line anti-TB drugs and can take two years or more to treat with drugs that are less effective, more toxic and more expensive.
    26. 26. Tuberculosis: vaccine • Bacille Calmette-Guerin (BCG): is a live attenuated strain of mycobacterium bovis. It is given in parts of the world where prevalence is high, or high risk of exposure like health care workers. • Other tuberculosis vaccines in development like MVA85A, rBCG30, 72F fusion protein, ESAT6-Ag85b fusion protein
    27. 27. Thanks I hope you enjoyed with this study.

    ×