Mycobacterium Sample Questions.pdf

Mycobacterium 1. What is the morphology of Mycobacterium in the light microscope? Answer: Slender/Slightly curved/ Straight rod shaped 2. What is the oxygen requirement for Mycobacterium to grow? Answer: Obligate aerobe 3. How long does Mycobacterium usually grow on a complex...

Mycobacterium 1. What is the morphology of Mycobacterium in the light microscope? Answer: Slender/Slightly curved/ Straight rod shaped 2. What is the oxygen requirement for Mycobacterium to grow? Answer: Obligate aerobe 3. How long does Mycobacterium usually grow on a complex media? Answer: 2-6 weeks 4. What type of Mycobacterium doesn't grow in vitro? Answer: M. Leprae 5. How long does rapid Mycobacterium grow on simple media? What temperature? Answer: 2-3 days @ 20-40C 6. What is the Mycobacterium Tuberculosis Complex consists of? Answer: M. tuberculosis, M. bovis, M. microti, M. africanum, M. canettii, M. pinnipedii, M. mungi, and M. orygis TB (MACPaMO) 7. What organism is associated with TB in tropical Africa? Answer: M. africanum 8. What organism is linked with TB among immunocompetent and immunocompromised? Answer: M. microti 9. What organism is found primarily in cattle but can infect other animals and humans? Answer: M. bovis 10. What organism causes infections in children and px with HIV in Africa? Answer: M. canettii 11. Who discovered M. tuberculosis? Answer: Robert Koch 12. T/F Is TB one of the oldest communicable diseases? Answer: True 13. Where does TB usually infect? Answer: Respiratory Tract 14. How does TB infect or mode of transmission? Answer: By inhaling tubercle bacilli droplets 15. How does M. Tuberculosis evades phagocytosis? Answer: Its thick lipid cell wall helps resist acidic environment and enzymatic conditions that kills most bacteria 16. In a person with adequate cellular immunity, what does macrophages secrete to enhance the inflammatory response? Answer: IL-12 and TNF 17. What secretes macrophages in the infection site to destroy the intracellular bacteria? Answer: IFN- gamma 18. What type of hypersensitivity does Mycobacterium activate? Answer: Type IV hypersensitivity 19. T/F Does PPD Skin Test imply recent infection of M. tuberculosis? Answer: False, It implies past infection 20. T/F Can Tuberculosis be reactivated to an active TB? Answer: True 21. In a chronic disease of TB, what diagnostic tests confirm tuberculosis? Answer: Stained smear and culture of sputum 22. What do you call tuberculosis that seeds to other organs? Answer: Miliary TB 23. What is the order of occurrence when TB infects/invades other organs? Answer: Spleen to Liver to Bone Marrow to Kidney to Adrenal Gland 24. How does AFB/Mycobacteria spread to these organs? Answer: Hematogenously 25. Who is mostly infected with Miliary TB? Answer: Children and px with HIV 26. What type of Miliary TB infects kidney and genital organs? Answer: Genitourinary TB 27. What type of Miliary TB manifest as typical UTI and sterile pyuria? Answer: Renal TB 28. What is the other term for Skeletal TB? Answer: Pott's Disease 29. How does tuberculosis infect the meninges? Answer: through the rupture of tubercle into the subarachnoid space 30. What are the primary drugs for Pulmonary Tuberculosis Answer: Rifampin, Isoniazid, Pyrazinamide, Ethambutol 31. Bacille Calmette-Guerin (BCG) is what type of vaccine? Answer: Live attenuated vaccine from 32. What other specimens can Mycobacteria be detected? Answer: Urine, feces, blood, CSF, tissue biopsy material and aspirates of any tissue 33. T/F: Delay in processing specimens for Mycobacteria advisable? Answer: False, since it can lead to false-negative results and increased bacterial contamination 34. What is the recommended specimen for sputum and other respiratory secretions? Answer: Early-morning specimen 35. What interval should be used in detecting Mycobacteria? Answer: 3 days consecutively 36. T/F: 2 of 3 positive sputum smears sufficient in confirmation of diagnosis Answer: True, however if only one of the smear comes positive,additional specimen is needed 37. What specimen is recommended for children and px who cannot form sputum? Answer: Gastric Aspirates and Washings 38. T/F Processing of 12-24 hours of pooled specimen is recommended for testing Mycobacteria? Answer: False, 12-24 is not recommended since it is contaminated and may contain few viable tubercle bacilli 39. T/F Stool specimen should be frozen if not process within few hours of collection Answer: True (MAHON) 40. What is the amount of specimens recommended for culture in CSF? Answer: 2 mL 41. What medium is used for heavily contaminated specimens for Mycobacterium tuberculosis testing? Answer: Petragani Medium 42. The solid medium most widely employed for routine culture Answer: Lowenstein–Jensen (L–J) medium 43. What type of medium does Mycobacteria spp. grow rapidly? Answer: Liquid Media 44. What dyes are used for fluorescence microscopy of smears? Answer: Auramine phenol or auramine rhodamine fluorescent dyes 45. In LJ medium, what common characteristic is used to describe Mycobacterium tuberculosis colonies? Answer: Cauliflower colonies