Lung Pathology Flashcards
How do you differentiated between lower and upper respiratory tract?
Upper= above larynx Lower= below larynx
What is the epithelium associate with respiratory tract?
Ciliated columnar epithelium
What happens to the alveolar in pneumonia?
Fill with oedema fluid, fibrin and inflammatory cells which forms CONSOLIDATION
What is opportunistic pneumonia and who is most at risk?
Pneumonia caused by atypical organism
People with weakened/under-developed immune system: Young Elderly Infirm Immunosuppressed
What are the 2 types of pneumonia?
Lobar pneumonia and bronchopneumonia
What is the cause of lobar pneumonia and what are the characteristic features?
What are the disease stages if left untreated?
Organism causes wide spread inflammation in whole lobe via spread through inter-alveolar pore (Kohn)
Features:
- well demarcated airless lobe compaction
- acute inflammation filling up alveoli
Stages:
Day 1= congestion
Day 2-4= Red hepatisation i.e. lungs resemble liver tissue
Grey hepatisation i.e. fibrin and WBC infiltrates
1-2 weeks= resolution
What are the complications associated with pneumonia?
- Death
- Hypoxaemia
- Septicaemia
- Metastatic infection via blood borne infection i.e. endocarditis/cerebral abscess
- Fibrosis
- Bronchiectasis
- Cavitation
- Abscess
- Fistula i.e. Broncho-pleural or broncho-vascular
- Empyema
- Pericarditis= infection spreads to local anatomical region
- Effusion
What causes bronchopneumonia?
Impaired host resistance due to:
- debility i.e. hypostasis due to being bedbound or elderly or aspiration
- lung disease i.e. chronic bronchitis/lung carcinoma/lung fibrosis
- systemic disease i.e. immunosuppression/organ failure/ neurological disease
Bronchopneumonia of the right lung is most likely caused by what?
Aspiration= easier route of access due to right bronchus being wider and shorter
What parts of the lungs are affected in bronchopneumonia?
Small bronchi with extension into adjacent tissue
Basal parts of lungs preferentially affected
What are 2 features seen in primary TB?
Ghon focus- small peripheral lung lesion
Ghon complex- hilar lymph node involvement
What can secondary TB result in?
Larger apical lesions
Pleural effusion with empyema
TB pneumonia
Miliary TB
Intestinal TB
How can you differentiate between primary and secondary TB?
Primary:
Lower-lobe (atypical)
Pleural effusion
Secondary:
upper lobe
Cavitation
What is the cause of pulmonary infarction? What contributes to an increased risk?
DVT i.e. termed a venous thrombo-embolism
Virchow’s triad for risk of clotting (vessel wall/blood flow/coagulability)
What normally prevents pulmonary infarct from occurring? Why then is it normally associated with patients who also have heart failure?
Lungs have dual blood supply from pulmonary artery and bronchial arteries meaning bronchial arteries can compensate when embolus in pulmonary artery to prevent infarct
HF= bronchial artery BF compromised -> infarct
When does a pulmonary infarction present?
24 hrs after survival of PE i.e. dependent on whether dual blood supply intact to maintain sufficient blood supply
What causes bronchial obstruction?
Inhaled foreign body
Tumour (carcinoid/carcinoma/lymphadenopathy)
What are the consequences of bronchial obstruction?
Mucostasis
-bronchial secretions collect distal to obstruction
Pneumonia
-infection due to retain secretions
Bronchiectasis
-weakening + dilation of bronchial walls
What are the 4 main causes of obstructive airways disease?
Asthma
Inflammation affecting bronchial mucous or hyper reactivity of SM
Chronic bronchitis
Emphysema
COPD/COAD (long standing air way restriction)
What is the definition of chronic bronchitis and what factors can lead to it’s development?
Productive cough lasting at least 3 months in 2 consecutive years
Cigarette smoking
Air pollution
Fumes
What pathological changes occur in chronic bronchitis?
Weakened bronchial walls
Hyperplasia of mucous glands
SM hyperplasia
Mucous plugs in lumina
What signs might someone with chronic bronchitis present with?
Reduced peak flow Raised residual volume Reduced maximum residual volume Recurrent low grade bronchial infections Hypoxaemia Cyanosis
What is emphysema and what are the consequence for the air ways?
Dilation of alveoli +/- respiratory bronchioles
Small airways collapse during exhalation due to loss of lung tissue causing the tension keeping the airways open to be lost
What is the difference between centrilobular and panacinar emphysema?
Centrilobular
- respiratory bronchioles affected
- cause= airborne irritants (cigarette smoke and occupational dusts)
Panacinar
- respiratory bronchioles and alveolar
- cause unknown but associated with alpha-1-antitrypsin deficiency
- prone to damage from proteolytic enzymes release from inflammatory cells by cigarette smoke
What is the role of cigarette smoke in centrilobular and panacinar emphysema?
C= acts as irritant P= stimulates proteolytic enzyme release from inflammatory cells which causes damage
What are the 2 major types of lung carcinoma? How is the treatment different for these cancers?
Small cell neuroendocrine carcinoma (SCUNC i.e. oat cell)
Chemo
Non-small cell carcinoma (NSCLC i.e. large cell)
Surgery/radiotherapy
What route does lung cancer spread and where does it metastasis to?
Lymphocytes-vascular spread
Mediastinal LN Liver BM Brain Pleural metastases Ipsilateral or contralateral lung
What are the paraneoplastic effects of lung carcinoma?
Epilepsy- due to cerebral metastasis
Bone pain and fractures
Finger clubbing- due to hypoxia
Ectopic hormone secretion = Increased ACTH and ADH= due to SCUNC secreting hormones
Weight loss + Cachexia (substantial loss of skeletal muscle due to cancer altering metabolism)
What are the local affects of lung carcinoma?
Destruction of bronchial wall and lung tissue
BV erosion
Bronchial obstruction
Pleural invasion= leads to malignant effusion
Pneumonia
What is the definition of pneumonia? What are the main causes?
Inflammation of lung parenchyma
Bacterial (most often)
Viruses
Fungi
Parasites
