Respiratory Pathology Flashcards
What type of epithelium lines the conducting airways?
Pseudostratified ciliated columnar mucus secreting epithelium
What cells line the alveoli?
Type 1 pneumocytes (gas exchange)
Type 2 pneumocytes (surfactant production)
When does respiratory failure occur?
When the PaO2 is less than 8Kpa
What is Type 1 respiratory failure?
When there is a Hypoxic drive and the paCO2 is less than 6.3kPa
What is Type 2 respiratory failure ?
Hypercapnic respiratory drive and the paCO2 is greater than 6.3kPa
What are some of the signs and symptoms of respiratory conditions?
1) Sputum (mucoid, purulent, haemoptysis)
2) Cough
3) Stridor (proximal airway obstruction)
4) Wheeze (distal airway obstruction)
5) Pleuritic pain
6) Dyspnoea (SoB due to impaired alveolar gas exchange??)
7) Cyanosis (decreased oxygenation of haemoglobin)
8) Clubbing
9) Weight loss (tumour)
What can be heard on auscultation?
1) Crackles (resisted opening of small airways)
2) Wheeze (narrowed small airways)
3) Bronchial breathing (sound conduction through solid lung)
4) Pleural rub (movement of inflamed visceral and parietal pleura)
Why would we hear a dull or hyperesonant sound upon percussion?
Dull is due to lung consolidation or pleural effusion.
Hyperesonant is due to pneumothorax or emphysema.
what is an adenochondroma?
It is a rare, benign primary lung tumour involving glandular and cartilagous tissue,
What are the risk factors of lung carcinoma?
- cigarettes
- asbestos
- lung fibrosis
- radon
- chromates, nickel, tar, hematite, arsenic, mustard gas
High levels of exposure to this substance leads to pulmonary instertitial fibrosis?
Asbestos
What type of cancer is cytokeratin and thyroid transcription factor positive?
Lung non mucinous adenocarcinoma and small cell
What type of cancer is cytokeratin 7 negative and cytokeratin 20 positive?
Colorectal and Upper GI tract
What is the site of squamous lung carcinoma?
More central than peripheral
What is the normal bronchus lined by?
Pseudostratified columnar epithelium with ciliated and mucus secreting cells
What happens in squamous metaplasia?
The epithelium undergoes metaplastic changes from psuedostratifies columnar to stratified squamous epithelium.
What is the process by which one cell undergoes irreversible genetic chances to produce the first neoplastic (cancerous) cell.
Dysplasia
Is bronchioloalveolar carcinoma invasive or non invasive?
non invasive
What neuroendocrine proteins are used as a marker for cancer and can be identified by immunocytochemistry?
1) Neural cell adhesion molecule (CD56)
2) Neurosecretory granule proteins (Chromogranin / Synaptophysin)
what are Kulchitsky cells?
Kulchitsky cells are neuroendocrine cells that are found in normal mucosa
EGFRs are transmembrane receptors present on cell membranes. They controll normal cell growth, apoptosis ect.
How do Tyrosine Kinase Inhibitors work as a cancer treatment in mutated EGFRs?
Mutations of EGFRs can activate receptors which lead to unregulated cell division.
Tyrosine Kinase inhibitors bind to the tyrosine kinase domain on the EGFR and stop it working.
Pneumothorax
air in the pleural cavity
Hydrothorax
transudate or exudate in the pleural cavity
Haemothorax
blood in pleural caviy
Chylothorax
lymph in pleural cavity
pyothorax
pus in pleural cavity
What causes lobar pneumonia in the elderly, diabetic and alcoholic?
Klebsiella pneumoniae
what is a ghon complex?
Ghon’s complex is a lesion seen in the lung that is caused by tuberculosis. The lesions consist of a calcified focus of infection and an associated lymph node.
where in the lung does tuberculosis usually reactivate?
apically
permanent dilation of bronchi and bronchioles caused by destruction of the muscles and elastic tissue
Bronchiectasis
give an example of an obstructive disease?
asthma
COPD
what 2 diseases make COPD
chronic bronchitis
emphysema
chronic inflammation of small airways of the lung causes wall weakness and destruction
chronic bronchitis
Abnormal permanent dilation of airspaces distal to the terminal bronchioles, with destruction of airspace wall, without obvious fibrosis
Emphysema
Is interstitial lung disease restrictive or obstructive?
restrictive
*increased tissue in the alveolar capillary walls along with inflammation and fibrosis decreases the lung compliance.
What are the features of acute interstitial disease?
- diffuse alveolar damage.
1) exudate and death of type 1 pneumocytes form hyaline membranes lineing alveoli.
2) type 2 pneumoncyte hyperplasia
What are the features of chronic interstitial lung disease?
- dyspnoea
- clubbing
- dry cough
- honeycomb lung
Non caseating perilyphatic pulmonary granulomas then fibrosis
Sarcoidosis
What are pneumoconioses also known as?
dust diseases
what is silicoses?
Sand/stone dust causes fibrosis
what is hypersensitivity pnumonitis?
extrinsix allergic alveolitis.
Type 3 hypersensitivity reaction to dust
What disease is caused by a mutation in the 7q31.2 gene?
cystic fibrosis
7q31.2 encodes a chloride channel protein/
