Histopathology - Respiratory pathology Flashcards
main cause of pulmonary oedema?
left heart failure
How does diffuse alveolar damage appear on CXR?
Firm and expanded lungs
What are 3 acute features of the airway in asthma?
Acute bronchospasm
Acute mucosal oedema
Inflammation
What are 3 chronic features of the airway in asthma?
Muscular hypertrophy
Airway narrowing
Mucus plugging
What are the features of COPD?
Chronic bronchitis and emphysema
Describe the features of chronic bronchitis
Chronic cough productive of sputum
Most days for at least 3 months over at least 2 consecutive years
How does chronic hypoxia affect the heart?
Pulmonary hypertension —> right heart failure
What is emphysema?
Permanent loss of the alveolar parenchyma distal to the terminal bronchiole
What is the genetic association of emphysema?
Alpha 1 anti-trypsin
Recall the pathophysiology of emphysema
Smoking causes inflammation
Neutrophil and macrophage involvement
Proteases recruited
Breakdown of epithelium
What does lung bullous rupture cause?
Pneumothorax
What is bronchiectasis?
Permanent abnormal dilatation of bronchi with inflammation and fibrosis into adjacent parenchyma
signet ring sign on CT
tram track opacity on CXR
Recall the complications of bronchiectasis
Haemoptysis
Pulmonary HTN
RHF
Amyloidosis secondary to chronic inflammation
Which condition has the strongest association with bronchiectasis?
Cystic fibrosis (CFTR mutation on Chromsome 7)
What is bronchopneumonia?
Inflammation centred around airway
Where does bronchopneumonia often affect?
Lower lobes
Which type of pneumonia has become much rarer since ABx have been in use?
Lobar pneumonia
What is empyema?
a collection of pus in the pleural space
Which type of pneumonia is most likely to cause interstitial inflammation?
Atypical pneumonias
What are the most common lung tumours?
small cell lung cancer (SCLC)
non small cell lung cancer (NSCLC) - most common
What are the 4 subtypes of malignant lung tumours?
Squamous cell carcinoma
Adenocarcinoma
Large cell carcinoma (20%)
Small Cell Lung Carcinoma aka oat cell (20%)
Which 2 types of lung cancer are most associated with smoking?
2S’s
Squamous cell
Small cell
Where is squamous cell carcinoma most likely to develop in the lung?
Centrally
Where do adenocarcinomas typically develop?
Peripherally
Which mutations are smokers most likely to develop in adenocarcinomas?
K ras
p53
Which mutations are non-smokers most likely to develop in adenocarcinomas?
EGFR
(epidermal growth factor receptor)
Which type of lung cancer is assoiated with the most paraneoplastic syndromes?
Small cell (SIADH)
What sign is the name of a palpable lymph node in the left supraclavicular fossa?
Troisier sign
Troisier’s sign is the finding of a palpable left supraclavicular lymph node; this is called Virchow’s node. It may indicate gastrointestinal malignancy, commonly of the stomach, or less commonly, lung cancer.
give 3 histological findings of asthma
Curschmann spirals - spiral-shaped mucus plugs from subepithelial mucous gland
Charcot- Leyden crystals
Eosinophils
interstitial lung disease shows what on spirometry
RESTRICTIVE lung disease
● Decreased CO diffusion capacity
● Decreased lung volume
● Decreased compliance
triad presentation of ILD
Chronic shortness of breath
End-inspiratory crackles
Cyanosis, pulmonary HTN and cor pulmonale
CT finding of ILD
honeycomb appearance
what cancer are women & non smokers likely to develop
adenocarcinoma
outline large cells carcinoma
poorly differentiated malignant epithelial tumour – large cells, large nuclei, prominent nucleoli.
outline mesothelioma
malignant tumour of the pleura - very poor prognosis
linked to asbestos exposure (long time lag)
more common in men
outline the 6 paraneoplastic syndromes
ADH - SIADH, causing hyponatraemia
ACTH - Cushings
PTH/PTHrp - primary hyperparathyroidism, hypercalcaemia and bone pain
calcitonin - bone pain
serotonin - carcinoid syndrome (flushing, diarrhoea, bronchoconstriction)
bradykinin - cough
which lung cancer is most likely to produce PTHrP
Squamous cell carcinoma is the most frequent type of PTHrP-producing lung cancer
does squamous or adenocarcinoma metastasise early or late
early mets - adenocarcinoma
late mets - squamous cell
define pulmonary hypertension
Mean pulmonary arterial pressure of >25mmHg at rest
2 consequences of pulmonary hypertension
RHF – venous congestion of organs (nutmeg liver), peripheral oedema.
2 histological findings of pulmonary oedema
intra-alveolar fluid,
iron laden macrophages (“heart failure cells”).
where do the majority of PE’s arise from
95% originate from DVT
occlusion of the pulmonary trunk with an embolus causes?
saddle embolus
-a large blood clot gets stuck in the main pulmonary artery, where bifurcation happens
presentation of Extrinsic Allergic alveolitis (3)
progressive persistent productive cough and SOB, finger clubbing and severe weight loss
identify early so can remove antigen
outline 5 types of EAA/hypersensitivity pneumonitis and the causative pathogens
- Farmers lung (mouldy hay/grain/silage – Saccharopolyspora rectivirgula), tend to get better over weekend
- Pigeon fancier’s lung (proteins in excreta/feathers),
- Humidifier’s lung (heated water reservoirs – thermactinomyces spp.),
- Malt-workers lung (germinating barley – Aspergillus clavatus/fumigatus),
- Cheese washer’s lung (mouldy cheese – Aspergillus clavatus/penicillium casei).
what is EAA/HP
immune-mediated lung disorders caused by intense/prolonged exposure to inhaled ORGANIC antigens → widespread ALVEOLAR inflammation
clinical presentation of idiopathic pulmonary fibrosis
increasing exertional dyspnoea and NON-productive cough. 40-70y at presentation, with hypoxaemia, cyanosis and pulmonary HTN +/- cor pulmonale, and clubbing.
investigation & 3 drug options for IPF
HR-CT ± biopsy diagnosis
steroids
cyclophosphamide
azathioprine
outline pneumoconiosis. most common in whom? what part of lung affected?
Occupational lung disease caused by inhlation of mineral dusts or inorganic particles.
Classically seen in coal miners.
The disease has a predilection for the upper lobes.
note asbestosis - prefers lower lobes
compare spirometry results in obstructive vs restrictive diseases
obstructive
Reduced FEV1 (<80% of the predicted normal)
Reduced FVC (but to a lesser extent than FEV1)
FEV1/FVC ratio reduced (<0.7)
restrictive
Reduced FEV1 (<80% of the predicted normal)
Reduced FVC (<80% of the predicted normal)
FEV1/FVC ratio normal (>0.7)
what lung cancer accounts for most cases of sueperior vena cava syndrome. what signs
small cell
shortnes of breath, swelling in face, venuous distension
also large B NHL
most pancoast tumurs are what type of lung cancer? what signs do they cause
most are NON small cell
cause horners - miosis (a constricted pupil), partial ptosis (a weak, droopy eyelid), apparent anhidrosis (decreased sweating)
