Pulmonary Pathology Flashcards
1
Q
Define acinus
A
Functional unit
Terminal Respiratory unit
Distal to terminal bronchioles
2
Q
LRT Parts
A
Trachea Bronchi Bronchioles Alveolar Ducts Alveolar Sacs
3
Q
Trachea anatomy
A
C shaped cartilage rings, mucous glands
4
Q
Bronchi anatomy
A
Discontinuous cartilage plates
Mucous glands
5
Q
Bronchioles anatomy
A
No cartilage or mucous glands
6
Q
Terminal bronchioles vs. respiratory bronchioles
A
Terminal = <2mm diametes Respiratory = for gas exchange
7
Q
Alveolar ducts anatomy
A
Flat epithelium, no glands or cilia
8
Q
Alveolar sacs anatomy
A
No glands or cilia
9
Q
Pulmonary oedema
A
Haemodynamic Cardiogenic Heavy wet lungs Alveolar pink granular fluid Brown induration if long standing
10
Q
Diffuse Alveolar Damage (ARDS; shock lung)
A
- oedema as alveolar capillary endothelium injury
- rapidly developing
- life threatening respiratory insufficiency
- oedema fluid and fibrous membranes lining alveoli
- proceeds to severe scarring
- does not resolve
11
Q
Causes of diffuse alveolar damage
A
shock trauma sepsis viral infections noxious gases radiation
12
Q
Emboli and infarction Types
A
- pulmonary artery occlusion due to circulating clots from lower limb veins in bedridden patients
- large saddle emboli = immediately fatal, lodge at pulmonary trunk bifurcation
- smaller emboli lodge peripherally = wedge shaped infarcts
13
Q
Pulmonary Hypertension
A
- pulmonary circulation low resistance
- increased pressure secondary to COPD, left valvular disease or recurrent thromboemboli
- = R. ventricular hypertrophy, chronic cor pulmonale
14
Q
Obstructive Pulmonary Disease Features
A
- increased resistance to airflow at any level
- no decreased in lung capacity
- reduced FEV1
- airway narrowing or loss of recoil
15
Q
Restrictive Pulmonary Disease Features
A
- reduced expansion of lung parenchyma
- decreased total lung capacity
- reduced TLC with proportionate FEV1 reduction
- chest wall disorders or interstitial/infiltrative diseases
16
Q
COPD examples
A
Chronic bronchitis
Emphysema
Bronchial Asthma
Bronchiectasis
17
Q
Chronic bronchitis and emphysema
A
- almost always co-existent
- almost always entirely due to smoking
18
Q
Define chronic bronchitis
A
Productive cough >3 months in 2 consecutive years
19
Q
Features of chronic bronchitis
A
- mucous gland hypertrophy
- mucous hypersecretion
- progressive
- hypoxia, hypercapnia
- cyanosis prone
- blue bloater
20
Q
Define emphysema
A
Permanent dilatation of airways distal to terminal bronchiole
21
Q
Features of emphysema
A
Centriacinar/panacinar/irregular
- elastin destruction = loss of elastic recoil
- hyperventilate
- normal blood gases
- pink puffers
22
Q
Types of Emphysema
A
- centriacinar = central/proximal bronchiole parts, smokers
- panacinar = uniform dilatation of acini form resp bronchiole to alveoli, A1AT deficiency
- paraseptal = peripheral, adjacent to scarring/collapse/fibrosis, predispose to spontaneous pneumothorax
- irregular = irreg. involvement of acini, scarring
23
Q
What does smoking do to cause emphysema?
A
Inhibits Alpha 1 anti-trypsin
Activated elastase
24
Q
Bronchial Asthma
A
- increased irritability of bronchial tree
- paroxysms of reversible bronchospasm
- most common is atopic = type 1 hypersensitivity
- others = aspirin induced, occupational, infection
25
Bronchiectasis
- permanent dilatation of bronchi and bronchioles with wall necrosis
- follows obstruction or childhood viral pneumonia
- airways = saclike, filled with foul smelling pus
- chronic paroxysmal cough brought on by posture change
- foul smelling sputum and lots
26
Complications of bronchiectasis
```
Abscess
Fibrosis
Amyloid
Clubbing
Cor pulmonale
```
27
Features of restrictive lung diseases
- diffuse and chronic damage to pulmonary interstitium, basement membranes, collagen fibres, elastic tissue, fibroblasts, few leucocytes
28
Physiological changes in restrictive lung disease
- reduced oxygen diffusing capacity, lung volume and lung compliance
29
CXR of restrictive lung disease
- diffuse infiltration by small nodules
- irregular lines
- ground glass shadows
30
Causes of restrictive lung diseases (common to least)
- most common = environmental/occupational (25%)
- sarcoidosis (20%)
- idiopathic pulmonary fibrosis (15%)
- collagen vascular diseases (10%)
31
Define Occupational lung Diseases
- caused by inhalation of dust particles, mineral or organic substances over many years due to occupational exposure
32
Features of occupational lung disease
- diffuse
- interstitial
- restrictive
33
2 mechanisms of injury to lung in occupational lung disease
1) scarring from chronic irritation = pneumoconiosis, coal
| 2) hypersensitivity = organic dusts
34
Examples of occupational lung diseases
- coal workers = pneumoconiosis, anthracosis, macules, progressive massive fibrosis
- siliconosis, caplan's syndrome
- asbestos = caplan synd, asbestosis, pleural plaques, cancers
- farmers lung, baggassosis
35
Sarcoidosis define
systemic disease of unknown cause
36
Characteristics of sarcoidosis
- non caseating granulomatous reaction in many tissues
- lung involved 90%
- varying severity
- incidental finding or respiratory/constitutional symptoms on presentation
- steroid therapy unpredictable
37
Lung cancer
- bronchogenic
- commonest site for secondary cancers
- commonest malignancy of western world
38
RF of lung cancer
- cigarette smoking
- asbestos
- mineral dusts
- radiation
- pollution
- scarring
39
Which cancers are caused by smoking?
- lip
- tongue
- floor of mouth
- larynx
- oesophagus
- urinary bladder
- pancreas
- kidney
40
How does smoking affect the respiratory epithelium?
- ciliated, mucus secreting, pseudostratified columnar
| - progresses to stratified squamous -> squamous dyplasia -> carcinoma
41
Histological classifications of lung cancer
- squamous cell carcinoma
- adenocarcinoma
- small cell (oat cell) carcinoma
- large cell carcinoma
42
Features of small cell carcinoma
- not treatable surgically
- widely disseminated
- chemo
43
Features of non small cell carcinoma
- surgical treatment
| - targeted therapy
44
How does targeted therapy work?
- blocking GF receptor signalling using an antibody or inhibiting the pathway
- stop vessel growth by the tumour
- encourage immune response to fight tumour cells
45
Non small cell cancer targeted therapy
- EGFR
- VEGF
- ALK-EML4 translocation
- ROS
- MET
- BRAF
46
Local clinical features of lung cancer
- cough
- haemoptysis
- pain
47
General clinical features of lung cancer
- weight loss
- clubbing
- hypertrophic pulmonary osteoarthropathy
48
Paraneoplastic syndromes
Feature of lung cancer
Due to ectopic hormone production by tumour cells
- e.g = hypercalcaemia, SIDAH
49
Prognosis of lung cancer
- overall 5 year survival = 10%
| - staging most important determinant of outcome
