11- Chronic inflammations -Tuberculosis.ppt

chronic inflammation- tuberculosis

5. CHRONIC PNEUMONIAS

6. Chronic Pneumonias
Often SYNONYMOUS with the 4 classic fungal or granulomatous
pulmonary infections .
If you see pulmonary granulomas, think of a CHRONIC process, often
years.

7. Include :
Tuberculosis
Histoplasmosis
Blastomycosis
Coccidioidomycosis : (kok-sid-e-oy-doh-my-KOH-sis)

8. 1-Histoplasmosis, Coccidioidomycosis, Blastomycosis
Usually normal host, but can be immunocompromised
Presentation & pathology very similar to T.B.
◦Acute primary pulmonary infection
◦Chronic cavitary pulmonary infection
◦Disseminated miliary infection
Lesion is granuloma with necrosis & giant cells
Important to Identify the organisms

9. Spores in bird
Histoplasma CAPSULATUM
Tiny organisms live in macrophages
Fill phagocytes in a lymph node of a patient with
disseminated histoplasmosis (silver stain)-Image
MANY other organs can be affected
HISTOPLASMOSIS

10. Spores in soil
Blastomyces DERMATIDIS
Large distinct SPHERULES
MANY other organs can be affected, especially SKIN
BLASTOMYCOSIS

11. Spores in soil
Coccidioides IMMITIS
Tiny organisms live in macrophages
intact spherules within multinucleated
giant cells.
MANY other organs can be affected
COCCIDIOMYCOSIS

12. Pathology of
tuberculosis of
lung

13. The World Health Organization (WHO) considers
tuberculosis (TB) to be the
most common cause of death
resulting from an endemic infectious agent
TB flourishes in the settings of poverty, crowding,
and chronic debilitating illness

14. Infection vs Disease
Infection implies seeding of a focus with organisms,
which may or may not cause clinically significant
tissue damage (i.e., disease)

16. Tuberculosis

17. Types of tuberculosis
Primary tuberculosis:
is a form of disease that develops in a previously unexposed and
therefore unsensitized person.
Secondary tuberculosis:
is the pattern of disease that arises in previously sensitized or infected
host.

20. TB CORD FACTOR is a
surface glycolipid

21. Helper T cells are activated and release
cytokines that recruit more macrophages to
that area

22. These macrophages, dead tissue, and bacteria
form the center of the granuloma, while helper
T-cells and multinucleated giant cells, which are
formed by the fusion of several macrophages, are
found on the periphery.

24. Epitheloid cells in Granuloma

26. Morphology of Granuloma
1.Rounded tight collection of chronic
inflammatory cells.
2.Central Caseous necrosis.
3.Actived macrophages -epithelioid cells.
4.Outer layer of lymphocytes & fibroblasts.
5.Langhans giant cells –joined epithelioid
cells.

27. Tuberculous Granuloma

30. Ghon Complex

31. A calcified ghon complex is called a
“Ranke complex”.

33. Secondary tuberculosis
Definition: the infection of an individual who has been previously
infected or sensitized
The infection may be acquired from
◦Endogenous source: reactivation of dormant primary complex
◦Exogenous source

34. Secondary tuberculosis
The initial lesion is a small focus of consolidation of <2cm
in diameter within 1 to 2cm of apical pleura
Gross: sharply circumscribed, firm, gray white to yellow
with variable amount of central caseation necrosis
Micro: coalescent tuberculous granulomas with central
caseation necrosis.

35. Tuberculous Granulomas

36. Caseation Necrosis

37. Fate of secondary tuberculosis
The lesion may heal with fibrous scarring and calcification
Fibro caseous tuberculosis (progressive pulmonary TB )
Tuberculous caseous pneumonia (Bronchopneumonia)
Miliary tuberculosis

38. Lung TB -Cavitation

39. Cavitary Secondary TB

40. Gross :
◦Tuberculous cavity is spherical with thick fibrous wall,
lined by yellowish, caseous, necrotic material.
◦The overlying pleura may also be thickened
Microscopy:
◦The wall of the cavity shows
◦Eosinophilic granular caseous material
◦Widespread tuberculous granulomas composed of central
caseous necrosis, epithelioid cells, Langhans giant cells and
peripheral zone of lymphocytes
◦The outer wall of the cavity shows fibrosis

41. Lung TB -Cavitation

42. Typical cavitating granuloma

43. Complications of cavitatory secondary TB
Extension to pleura producing bronchopleural
fistula
Tuberculous empyema
Thickened pleura
Pleural effusions
Obliterative fibrous pleuritis

44. Miliary pulmonary tuberculosis
Occurs when organisms drain through lymphatics
intolymphatic ductsvenous return on the right
side of heartpulmonary arteries
Individual lesions are either microscopic or small,
visible (2mm) foci of yellow-white consolidation
scattered through the lung parenchyma (resembling
millet seeds)
Micro: the lesion shows structure of granuloma with
minute areas of caseous necrosis.

45. Miliary TB

53. Pathogenesis

55. Diagnosis of TB
Clinical features are not confirmatory.
Zeil Nielson Stain
Adenosine deaminase test
Culture most sensitive and specific test.
◦Conventional Lowenstein Jensen media 3-6 wks.
◦Automated techniques within 9-16 days
PCR is available, but should only be performed by
experienced laboratories
Mantoux test

56. AFB -Ziehl-Nielson stain

58. Colony Morphology –LJ Slant

59. Mantoux test
Infection with mycobacterium tuberculosis leads delayed
hypersensitivity reaction which can be detected by Mantoux test
About 2 to 4 weeks after infection, intracutaneous injection of
purified protein derivative (PPD) of M.tuberculosis induces a visible
and palpable induration that peaks in 48 to 72 hours

60. PPD Tuberculin Testing
Sub cutaneous
Weal formation
Itching –no scratch.
Read after 72 hours.
Induration size.
5-10-15mm

61. (i) Induration less than 5 mm –no exposure to
tubercular bacilli.
(ii) Induration between 5-9 mm –this can be due to
atypical mycobacteria or BCG vaccination. It may
suggest infection in immunocompromised children
such as HIV infection or other immunosupression;
(iii) Induation 10 mm or more –an induration of 10
mm or more at 48-72 hours in a child with
symptoms of tuberculosis should be interpreted as
tubercular disease

62. PPD result after –72 hours.

63. Granuloma or giant cell is notpathagnomonic of
TB…!
Foreign body granuloma.
Fat necrosis.
Fungal infections.
Sarcoidosis.
Crohns disease.

64. Conclusions:
Chronic, Mycobacterial, infection -Weight loss, fever, night sweats, lung
damage.
Commonest fatal infection in the world.
CXR -apical lesions.
AIDS, Diabetes, malnutrition & crowding.
Two forms Primary, Secondary
Pulmonary, extrapulmonary, miliary.
Multi drug treatment to prevent resistance