Mycobacterium tuberculosis, Mycobacterium leprae, and Mycobacterium avium-intracellulaire complex are important human pathogens. These mycobacteria have unusual lipid-rich cell walls containing mycolic acids. M. tuberculosis causes tuberculosis, which can progress to pneumonia, granuloma formation, caseous necrosis, calcification, and cavity formation in the lungs. M. leprae causes leprosy, which presents as tuberculoid or lepromatous forms depending on immune response. M. avium-intracellulaire complex causes opportunistic infections in AIDS patients associated with CD4 counts.

2. Mycobacterium

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

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

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

6. 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)

7. Improved Mycobacterial Isolation Medium

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

9. Pathogenic Mycobacterium spp.
BCG
AIDS
patients

10. Mycobacterial Clinical Syndromes

11. 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.

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

13. Differential Characteristics of
Commonly Isolated
Mycobacterium spp.

15. Mycobacterium
tuberculosis

16. Mycobacterium
tuberculosis
Infections

17. Incidence of Tuberculosis in USA

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

19.  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

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

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

22. Mycobacterium Tuberculosis
Stained with Fluorescent Dye

24. Mycobacterium leprae

25. Mycobacterium leprae Infections

26. Mycobacterium leprae Infections (cont.)

27. Tuberculoid vs. Lepromatous Leprosy
Clinical Manifestations and Immunogenicity

28. Lepromatous vs. Tuberculoid Leprosy

29. Lepromatous Leprosy (Early/Late Stages)

30. Lepromatous Leprosy Pre-
and Post-Treatment

31. Clinical Progression of Leprosy

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

34. Mycobacterium avium-
intracellulaire Complex
(MAC)

35. Mycobacterium avium-intracellulaire Infections

36. Mycobacterium avium-intracellulaire Infections

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

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

40. REVIEW
of
Mycobacterium

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

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

43. Pathogenic Mycobacterium spp.
BCG
AIDS
patients
REVIEW

44. Mycobacterial Clinical Syndromes
REVIEW

45. 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

46. Review of
Mycobacterium
tuberculosis

47. Mycobacterium
tuberculosis
Infections
REVIEW

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

49.  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

50. Review of
Mycobacterium leprae

51. Mycobacterium leprae Infections
REVIEW

52. Mycobacterium leprae Infections (cont.)
REVIEW

53. Lepromatous vs. Tuberculoid Leprosy
REVIEW

54. Lepromatous Leprosy (Early/Late Stages)
REVIEW

55. Clinical Progression of Leprosy
REVIEW

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

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

58. Mycobacterium avium-intracellulaire Infections
REVIEW

59. Mycobacterium avium-intracellulaire Infections
REVIEW

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