This document summarizes various pathologies of the lung including atelectasis, acute lung injury, ARDS, emphysema, chronic bronchitis, asthma, bronchiectasis, pneumonia, lung abscess, Good Pasture's syndrome, lung tumors, and a therapeutic classification of lung cancers. It describes the causes, symptoms, and pathology of each condition in detail over multiple paragraphs.

1. Pathology of lung

4. Atelectasis
 Loss of lung volume due to inadequate
expansion of air spaces
1. Resorption
2. Compression/passive/relaxation/flaccid
3. Contraction /Cicatriztion
4. Non obstructive/micro

5. Acute lung injury
Spectrum of endothelial and epithelial
pulmonary lesions
Acute onset of dyspnea
B/l pulmonary edema
Hypoxemia
No LHF
Pathology of vasculature- alveolar
capillary membrane damage
Non cardiogenic pulmonary edema

6.  Acute injury can be
1. Direct injury- Pneumonia,aspiration of
gastric contents
2. Indirect injury- sepsis,severe trauma with
shock
3. A/c injury----------- ARDS

7. ARDS
 Diffuse alveolar capillary and epitrhelial
damage
1. Respiratory insufficiency
2. Cyanosis
3. Severe arterial hypoxemia-not
responding to oxygen therapy
4. Progress to mutisystem organ failure
 Neutrophils hav a imp role in ARDS

9. Destructive forces are counter acted by
anti proeases, oxidents ,etc
Degree of tissue injury depends on
balance of two

11. Emphysema
1. Centri acinar/centri lobar- in smokers-
2. Pan acinar/pan lobar- ass. With alpha 1
anti trypsin deffi.
3. Distal acinar/para septal- adj. to scarring,
fibrosis,atelectasis
4. irregular- associated with scarring-
assymptomatic

15. C/C Bronchitis
 Persistent productive cough for 3 consecutive
months for 2 consecutive years
 Three types
1. Simple c/c bronchitis-productive cough—
mucoid sputum—air flow not obstructed
2. C/C asthmatic bronchitis-hyper responsive
airways—intermittent bronchospasm and
wheezing
3. C/C obstructive bronchitis-associated with
emphysema

17. Asthma
 Air way remodeling
 ADAM33
1. Thickening of basement membrane of
bronchial epithelium
2. Edema & inflammatory infiltrate in the
bronchial walls,with a prominnce of eosinophils
and mast cells
3. An increase in size of submucosal glands
4. Hypertrophy of bronchial smooth muscles

19. Bronchiectasis

20. Pneumonia

21.  Two types
1. Broncho
2. Lobar
 Mostly occurs by aspiration of
pharyngeal flora
 Lower lobes/ right middle lobes are
mostly affected

22. 1. Community- acquired Acute pneumonia-
pyogenic org.
2. Community acquired atypical pneumonia-
virus, mycoplasma, candida
3. Nosocomial- pseudomanas,gram neg.
4. Aspiration – anerobic
5. Chronic – Mtb
6. Necrotizing pneumonia and lung abcess-
Anerobic + pyogenic
7. Pneumonia in the immunocompramised host
– chlamydia, aspergillosis, CMV

24. Complications of pneumonia
 Lung abscess
 Empyema- suppurative materials may
accumulate in the pleural cavity
 Bacterial dissemination leading to
meningitis,arthritis, infective endocarditis
 Complications are much more with
serotype 3 pneumococci

25. Atypical pneumonias
Acute febrile respiratory d/s characterized
by patchy consolidation of lungs, largely
confined to alveolar septa and pulmonary
interstitium
Atypical-moderate amounts of sputum,
absence of physical finings of
consolidation,only moderate inc in WBC
coun,lack of alveolar exudate
Mostly by Mycoplasma pneumoniae

27. Lung Abscess
Suppurative destruction of lung
parenchyma with central area of cavitation

29. Good Pasture’s syndrome
RPGN
Haemorrhagic interstitial pneumonitis

30. Lung tumours
1. Squamous cell carcinoma/epidermoid
carcinoma
2. Adinocarcinoma-bronchial derived,
acinar,papillary,broncioloalveolar,solid
3. Small cell carcinoma-oat cell, intermediate
4. Large cell carcinoma,undiff,giant cell, clear cell
5. Others- combined small cell
carcinoma,Adenosquamous carcinoma

31. Adenocarcinoma has replaced SCC as
the most common primary lung tumour
Most common in women,non
smokers,persons younger than 45yrs

32. Therapeutic classification
1. Small cell lung cancer (SCLC)
2. Non small cell lung cancer (NSCLC)