TUBERCULOSIS

1. TUBERCULOSIS Dr. Mohammed Farouq

2. ETIOLOGY Mycobacterium tuberculosis Mycobacterium avium Mycobacterium bovis [rare]

3. CHARACTERISTICS curved rods obligate aerobes acid-fastness

5. Mycobacteria can also be stained with auramine and viewed with fluorescence microscopy, in which acid fast bacilli now appear as glowing yellow rods. This method is easier to use to screen for mycobacteria and is the method routinely used in sputum specimens sent to the laboratory. Mycobacteria can also be stained with auramine and viewed with fluorescence microscopy, in which acid fast bacilli now appear as glowing yellow rods. This method is easier to use to screen for mycobacteria and is the method routinely used in sputum specimens sent to the laboratory.

7. EPIDEMIOLOGY High Risk Factors: Infants overcrowding and bad hygiene Immunosuppresive states lymphoma viral illness: measles, HIV drugs eg. steroids

8. TRANSMISSION Person to person Inhalation of contaminated droplets from an infected adult

9. INFECTIVITY (source of infection) Adolescents and adults Young children (rare) Tubercle bacilli are sparse in the endobronchial secretions cough is weak or absent

10. INCUBATION PERIOD 2 - 8 weeks

11. CLINICAL MANIFESTATIONS

12. INFECTION (Latent TB Infection) Preclinical stage of infection No clinical features Normal CXR PPD-positive only

13. DISEASE (Active TB) Clinical manifestations are present (Symptoms and signs or chest x-ray findings)

14. Pulmonary Disease

15. Primary Pulmonary Disease 1. Asymptomatic with Hilar adenopathy 2. Symptomatic : Pneumonia: 70% subpleural infiltrate hilar adenopathy Nonproductive cough and mild dyspnea Some infants have failure-to-thrive

16. Right upper lobe consolidation hilar fullnessRight upper lobe consolidation hilar fullness

17. Chest x-ray reveals right upper lobe consolidation with scattered air bronchograms. There is hilar fullness bilaterally and in the right paratracheal region. No pleural effusion is identified. Chest x-ray reveals right upper lobe consolidation with scattered air bronchograms. There is hilar fullness bilaterally and in the right paratracheal region. No pleural effusion is identified.

18. Complicated Primary Pulmonary Disease Parenchyma 1. Progressive Primary Pulmonary Disease High fever severe cough with sputum production weight loss, and night sweats ( common) diminished breath sounds, crepitations

19. Complicated Primary Pulmonary Disease Regional lymph nodes 2. Tracheobronchial lymph node disease focal hyperinflation ? wheezing atelectasis 3. Endobronchial disease collapse-consolidation or segmental tuberculosis

20. Complicated Primary Pulmonary Disease 4. Pleural Effusion 6-12 months after the infection usually > 6 years Asymptomatic local pleural effusion with primary disease Larger effusions occur later radiographic resolution often takes months. The tuberculin skin test is positive in 70�80% of cases The prognosis is excellent

21. A PA view is shown here. His chest radiograph demonstrates a complete opacification of the right hemithorax with a shift of the mediastinal structures to the left. This patient presents with primary tuberculosis (TB) and a pleural effusion. A PA view is shown here. His chest radiograph demonstrates a complete opacification of the right hemithorax with a shift of the mediastinal structures to the left. This patient presents with primary tuberculosis (TB) and a pleural effusion.

22. Secondary or Reactivation Tuberculosis Mostly adolescents of adults Rare in children, localized to the lungs (upper lobes) Fever, malaise, weight loss, night sweats, productive cough, chest pain Physical examination findings usually are minor or absent, Highly contagious

23. Systemic Disease

24. Miliary tuberculosis 2�6 mo after the primary infection common in infants and young children onset is insidious or acute anorexia, weight loss low-grade fever later high lymphadenopathy &hepatosplenomegaly(50%) progressive pulmonary disease (respiratory distress, pneumothorax, pneumomediastinum)

25. Miliary tuberculosis meningitis (20�40%) Choroid tubercles occur in 13�87% The tuberculin skin test is nonreactive in up to 40% Early sputum or gastric aspirate cultures have a low sensitivity. Biopsy of the liver or bone marrow offer better yield

26. Hilar lymph nodesHilar lymph nodes

27. Adenopathy

28. TB adenitis within 6�9 months tonsillar, anterior cervical, submandibular, and supraclavicular nodes epitrochlear, axillary, inguinal early: firm, discrete, nontender later: matting, feel fixed to underlying or overlying tissue The tuberculin skin test is usually reactive. The chest radiograph is normal in 70% of cases. Culture of lymph node tissue yields the organisms in about 50%

29. TB adenitis Differential diagnosis pyogenic infection nontuberculous mycobacteria (NTM) cat-scratch disease Toxoplasmosis Tumor branchial cleft cyst cystic hygroma

30. CNS Disease

31. Meningitis Common in children between 6 mo and 4 yr of age. Gradual onset. Lethargy, headache, vomiting, seizures. Cranial nerve palsies, focal neurologic signs. decerebrate posturing, death.

32. Meningitis The tuberculin skin test is nonreactive in up to 50% 20�50% of children have a normal chest radiograph CSF analysis Leukocyte count 10 to 500 cells/mm3 (lymphocytes) Glucose less than 40 mg/dl Protein level is elevated

34. Tuberculomas The tuberculin skin test is usually reactive Chest radiograph is usually normal Surgical excision Corticosteroids CT scan or MRI of the brain Angiographic studies (avascular)

35. Other Systems Abdominal T.B Peritonitis Mesenteric adenitis malabsorption, fistula formation, Bone and Joint Disease spine ? Pott�s disease Hip, knee Cutanenous Ocular

36. DIAGNOSIS History Physical examination Tuberculin Skin Tests ( Mantoux tuberculin skin test) Demonstration of Acid Fast Bacilli (Ziehl-Neelsen stain) Culture sputum/gastric washings Pleural fluid, CSF, urine Biopsy material

37. DIAGNOSIS Radiological Examination CXR, CT, MRI, IVP Histological diagnosis QuantiFERON (LTBI) POLYMERASE CHAIN REACTION (PCR) Increased ESR, anemia, lymphocytosis

38. Tuberculin Skin Test (PPD) intradermal injection of 0.1 ml. Containing 5 tuberculin units (TU) of purified protein derivative (PPD) stabilized with Tween 80. The amount of induration in response to the test should be measured by a trained person 48�72 hr.

39. False negative reactions Very young age. Malnutrition. immunosuppression. Overwhelming tuberculosis. Corticosteroid therapy. 10%-50% of those with meningitis or disseminated disease. Poor technique or misreading the results.

40. Interpretation Of The PPD Skin Test >5 mm Induration ? POSITIVE For adults and children at the highest risk of infection recent contact with infectious persons clinical illnesses consistent with tuberculosis HIV infection or other immunosuppression

41. Interpretation Of The PPD Skin Test >10 mm Induration ? Positive All other children in endemic ares

42. TREATMENT USE MULTIPLE DRUGS Bactericidal Drugs Isoniazid, rifampin, Streptomycin Pyrazinamide Bacteriostatic Drugs ethambutol at low doses ethionamide cycloserine

43. ISONIAZID (INH). daily dose of 10 mg/kg metabolized by acetylation in the liver Peripheral neuritis Hepatotoxicity increase phenytoin levels interacts with theophylline hemolytic anemia in patients with glucose-6-phosphate dehydrogenase deficiency lupus-like reaction with skin rash and arthritis.

44. RIFAMPIN (RIF) orange discoloration of urine and tears gastrointestinal disturbances hepatotoxicity thrombocytopenia influenza-like syndrome render oral conceptives ineffective interacts with several drugs, including quinidine, sodium warfarin, and corticosteroids

45. PYRAZINAMIDE (PZA) 30 mg/kg/24 hr Arthralgias arthritis, or gout hepatotoxicity

46. STREPTOMYCIN (STM). given intramuscularly when initial INH resistance is suspected when the child has a life-threatening form of tuberculosis Toxicity to the vestibular and auditory portions of the 8th cranial nerve. Renal toxicity contraindicated in pregnant women

47. ETHAMBUTOL (EMB) 25 mg/kg/24 hr EMB has some bactericidal activity treatment of drug-resistant disease optic neuritis

48. OTHER DRUGS Aminoglycosides (kanamycin and amikacin) Capreomycin Cycloserine Ciprofloxacin and ofloxacin are fluoroquinolones

49. Pulmonary tuberculosis 6 mo of INH and RIF supplemented during the first 2 mo by PZA administration be directly observed If community rate of INH resistance > 5�10% add a 4th drug� STM, EMB, or ETH

50. Extrapulmonary tuberculosis same as for pulmonary tuberculosis 9�12 mo bone and joint tuberculosis Tuberculous meningitis

51. Corticosteroids tuberculous meningitis endobronchial tuberculosis pericardial effusion pleural effusion severe miliary tuberculosis prednisone 1�2 mg/kg/24 hr in 1�2 divided doses for 4�6 wk with gradual tapering.

52. Supportive Care Adequate nutrition Bed rest REGULAR FOLLOWUP

53. TREATMENT OF LTBI 9 mo of daily INH therapy

54. PREVENTION Bacille Calmette-Gu�rin Vaccination intradermal injection Local ulceration regional suppurative adenitis occur in 0.1�1% Osteitis is a rare disseminated BCG infection BCG is 50%�80% effective in disseminated and meningeal tuberculosis