This document discusses Mycobacterium species, including M. tuberculosis, M. leprae, and M. avium-intracellulaire complex (MAC). It covers the characteristics, diseases caused, and clinical presentations of infections by these mycobacteria. Key points include: M. tuberculosis is the primary cause of tuberculosis and a leading global infectious killer; M. leprae causes leprosy; and MAC can cause disseminated disease in AIDS patients with low CD4 counts. The review section summarizes the pathogenic mycobacteria, diseases they cause, clinical manifestations, histopathology, and effects of immunity.

1. Mycobacterium
Dr. J Sheehama
UNAM School of Medicine

2. Tuberculosis is a
leading cause of death
worldwide (~1.4
million)*
Namibia
Population: 2.1 million
In 2009: TB case
notification rate of 634
per 100 000**
In 2010: TB case
notification rate of 589
*WHO
** MoHSS
Introduction and background

3. • Pulmonary TB is caused by Mycobacterium tuberculosis
– Lung is the prime target for infections
• TB is one of the opportunistic infections in HIV-AIDS
patients
Introduction and background information

4. Introduction and background
• Transmission of TB

5. Mycobacterium tuberculosis
Mycobacterium leprae (uncommon)
Mycobacterium avium-intracellulaire Complex
(MAC) or (M. avium)
Important Human Pathogens

6. Lipid-Rich Cell Wall of Mycobacterium
Mycolic acids
CMN Group:
Unusual cell wall
lipids (mycolic
acids,etc.)
(Purified Protein Derivative)

7. Acid-Fast (Kinyoun) Stain of
Mycobacterium
NOTE: cord growth (serpentine
arrangement) of virulent strains

8. Photochromogenic Mycobacterium
kansasii on Middlebrook Agar
NOTE: Mycobacteria pathogenic
for humans can be differentiated
(Runyon Groups) by:
 speed of growth (all are
slower than most other
pathogens) and by
 production of chromogenic
pigments (in light, in dark,
or none)

9. Improved Mycobacterial Isolation Medium

10. Eight Week Growth of
Mycobacterium tuberculosis on
Lowenstein-Jensen Agar

11. Pathogenic Mycobacterium spp.
BCG
AIDS
patients

12. Mycobacterial Clinical Syndromes

13. Diagram
of a
Granuloma
NOTE: ultimately a
fibrin layer develops
around granuloma
(fibrosis), further
“walling off” the
lesion.
Typical progression
in pulmonary TB
involves caseation,
calcification and
cavity formation.

14. Laboratory Diagnosis of
Mycobacterial Disease
Nucleic acid probes
Nucleic acid sequencing

15. Differential Characteristics of
Commonly Isolated
Mycobacterium spp.

17. Mycobacterium
tuberculosis

18. Mycobacterium
tuberculosis
Infections

19. Incidence of Tuberculosis in USA

20. Mycobacterium
tuberculosis
Infections (cont.)
BCG (bacille Calmette-Guerin)
= attenuated M. bovis
Positive PPD + Chest X-Ray +
MDR-TB a serious
global health threat

21.  Pneumonia
 Granuloma formation with fibrosis
 Caseous necrosis
• Tissue becomes dry & amorphous (resembling cheese)
• Mixture of protein & fat (assimilated very slowly)
 Calcification
• Ca++ salts deposited
 Cavity formation
• Center liquefies & empties into bronchi
Typical Progression of
Pulmonary Tuberculosis

22. PPD Tuberculosis Skin Test Criteria
PPD = Purified Protein Derivative from M. tuberculosis

23. Chest X-Ray of Patient with Active
Pulmonary Tuberculosis

24. Mycobacterium Tuberculosis
Stained with Fluorescent Dye

26. Mycobacterium leprae

27. Mycobacterium leprae Infections

28. Mycobacterium leprae Infections (cont.)

29. Tuberculoid vs. Lepromatous Leprosy
Clinical Manifestations and Immunogenicity

30. Lepromatous vs. Tuberculoid Leprosy

31. Lepromatous Leprosy (Early/Late Stages)

32. Lepromatous Leprosy Pre-
and Post-Treatment

33. Clinical Progression of Leprosy

34. Effect of Cell-Mediated Immunity on
Leprosy Clinical Outcome

36. Mycobacterium avium-
intracellulaire Complex
(MAC)

37. Mycobacterium avium-intracellulaire Infections

38. Mycobacterium avium-intracellulaire Infections

39. M. avium-
intracellulaire
Complex (MAC)
Progression vs.
CD4 Count in
AIDS Patients

40. Mycobacterium avium-intracellulaire in
Tissue Specimens
Low Magnification High Magnification

42. REVIEW
of
Mycobacterium

43. Mycobacterium tuberculosis
Mycobacterium leprae (uncommon)
Mycobacterium avium-intracellulaire Complex
(MAC) or (M. avium)
Important Human Pathogens
REVIEW

44. Lipid-Rich Cell Wall of Mycobacterium
Mycolic acids
CMN Group:
Unusual cell wall
lipids (mycolic
acids,etc.)
(Purified Protein Derivative)
REVIEW

45. Pathogenic Mycobacterium spp.
BCG
AIDS
patients
REVIEW

46. Mycobacterial Clinical Syndromes
REVIEW

47. Diagram
of a
Granuloma
NOTE: ultimately a
fibrin layer develops
around granuloma
(fibrosis), further
“walling off” the
lesion.
Typical progression
in pulmonary TB
involves caseation,
calcification and
cavity formation.REVIEW

48. Review of
Mycobacterium
tuberculosis

49. Mycobacterium
tuberculosis
Infections
REVIEW

50. Mycobacterium
tuberculosis
Infections (cont.)
BCG (bacille Calmette-Guerin)
= attenuated M. bovis
Positive PPD + Chest X-Ray +
MDR-TB a serious
global health threat
REVIEW

51.  Pneumonia
 Granuloma formation with fibrosis
 Caseous necrosis
• Tissue becomes dry & amorphous (resembling cheese)
• Mixture of protein & fat (assimilated very slowly)
 Calcification
• Ca++ salts deposited
 Cavity formation
• Center liquefies & empties into bronchi
Typical Progression of
Pulmonary Tuberculosis
REVIEW

52. Review of
Mycobacterium leprae

53. Mycobacterium leprae Infections
REVIEW

54. Mycobacterium leprae Infections (cont.)
REVIEW

55. Lepromatous vs. Tuberculoid Leprosy
REVIEW

56. Lepromatous Leprosy (Early/Late Stages)
REVIEW

57. Clinical Progression of Leprosy
REVIEW

58. Effect of Cell-Mediated Immunity on
Leprosy Clinical Outcome
REVIEW

59. Review of
Mycobacterium avium-
intracellulaire Complex
(M. avium)

60. Mycobacterium avium-intracellulaire Infections
REVIEW

61. Mycobacterium avium-intracellulaire Infections
REVIEW

62. M. avium-
intracellulaire
Complex (MAC)
Progression vs.
CD4 Count in
AIDS Patients
REVIEW

63. Home work – Due
25/02/2015
– describe the risk factors
of TB infection in your
Region