pathology of lung
TRANSCRIPT
Pathology of lung
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
Acute lung injury
Spectrum of endothelial and epithelial pulmonary lesions
Acute onset of dyspneaB/l pulmonary edemaHypoxemiaNo LHFPathology of vasculature- alveolar
capillary membrane damage Non cardiogenic pulmonary edema
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
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
Destructive forces are counter acted by anti proeases, oxidents ,etc
Degree of tissue injury depends on balance of two
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
C/C Bronchitis
Persistent productive cough for 3 consecutive months for 2 consecutive years
Three types1. Simple c/c bronchitis-productive cough—
mucoid sputum—air flow not obstructed2. C/C asthmatic bronchitis-hyper responsive
airways—intermittent bronchospasm and wheezing
3. C/C obstructive bronchitis-associated with emphysema
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
Bronchiectasis
Pneumonia
Two types
1. Broncho
2. Lobar Mostly occurs by aspiration of
pharyngeal flora Lower lobes/ right middle lobes are
mostly affected
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
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
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
Lung Abscess
Suppurative destruction of lung parenchyma with central area of cavitation
Good Pasture’s syndrome
RPGNHaemorrhagic interstitial pneumonitis
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
Adenocarcinoma has replaced SCC as the most common primary lung tumour
Most common in women,non smokers,persons younger than 45yrs
Therapeutic classification
1. Small cell lung cancer (SCLC)
2. Non small cell lung cancer (NSCLC)