Pathology of Restrictive lung disease Flashcards

(60 cards)

1
Q

Where does restrictive lung diseases affect the lungs

A

In the Interstitium lying within the alveoli of the lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the interstinum of the lung

A

potential space between alveolar epithelium and alveolar capillary endothelium, which sit on basement membranes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the outcome of restrictive lung disease

A

reduces the lungs compliance - creates a stiff lung
reduced total lung capacity
reduced gas transfer
ventilation/perfusion imbalance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the result of restrictive lung disease on the FEV1 FVC and their ratio

A

FEV1 AND FVC are reduced,

but the FEV1/FVC ratio remains the same

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What causes the reduction of the total lung capacity in restrictive lung disease

A

altering of lung parenchyma - portion of the lung involved in gas transfer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

In normal alveolar wall what is the relationship between e alveolar epithelial and intersitial capillary endothelial cell basement membranes, what does this allow

A

direct contact allowing efficient gas exchange

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the pathological process of restrictive lung disease and what does it result in

A

interstitial inflammation
alveolar wall thickening due to interstital filtrate
potentially resulting in scaring and fibrosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the clinical presentations of restrictive lung disease

A

Dyspnoea:
shortness of breath during exercise followed by at rest
Respiratory failure type 1 (reduced oxygen in the blood)
Heart failure
Abnormal Chest X-ray

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the overall aetiology of restrictive lung disease

A

Something damages the lung tissue parenchymal and the lung injury leads to an inflammatory process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the two responses to Parenchymal (Interstitial) Lung Injury

A

either chronic or acute

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the the further responses of the chronic response to parenchymal lung injury

A

interstitial pneumonitis response
granulomatous response
or other patterns

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the acute response to Parenchymal (Interstitial) Lung Injury

A

Diffuse alveolar damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the potential causes of Diffuse alveolar damage

A
Major trauma
Chemical injury / toxic inhalation
Circulatory shock
Drugs 
Infection
Auto(immune) disease
Radiation
idiopathic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the two stages in the pathology of Diffuse alveolar damage

A

Exudative stage

proliferation stage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What steps occur in the exudative stage of diffuse alveolar damage

A
  1. Damage and destruction to the endothelia cells results in the capillary cells becoming very leak
  2. The leads to a massive pulmonary oedema - much more than acute inflammatory response
  3. alveolar spaces fill with protein rich fluid
  4. The massive outpour of macromolecule and proteins form a layer on the degraded basement membrane
  5. Form hyaline membrane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does the body want to achieve in proliferation stage of diffuse alveolar damage

A

The body wants to repair the damage to the alveoli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the outcome of the proliferation stage of diffuse alveolar damage

A

alveolar proliferation leads to a mixture of fibril and inflammatory cells, these then attempt to repair the damage by laying down rapid fibrosis tissue, thus creating a solid mass in the lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the outcome of most patients with Diffuse alveolar damage

A

Its a fatal disease as may patients die from respiratory distress ARDS, shocked lung etc, as lung loses all compliance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the histological features of DAD

A
Protein rich oedema
Fibrin
Hyaline membranes - Epithelial proliferation
Fibroblast proliferation
Scarring - interstitium and airspaces
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the two Granulomatous responses in Parenchymal (Interstitial) Lung Injury

A

sarcoidosis

Hypersensitivity pneumonitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is sarcoidosis

A

is a mulit granulomatous disorder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Do sarcoidosis granulomas cause necrosis

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How can you differentiate between sarcoidosis and TB

A

caseations are very unusual in sarcoidosis, but necrosis occur in TB, causing these caseation cheese like appearance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the most key feature of sarcoidosis

A

The alveoli around the granulomas are normal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
How does scarring occur in sarcoidosis
fibrosis of the granuloma
26
sarcoidosis is a multi system disorder but what is the most common sites of infection
Skin, Lungs and lymph nodes | eyes - sometimes
27
What is the symptoms of sarcoidosis
Tender reddish bumps or patches on the skin (Erythema nodosum) Red and teary eyes or blurred vision. Swollen and painful joints (acute arthralgia) Bilateral hilar lymphadenopathy - enlarged lymph shortness of breath cough abnormal CXR
28
What specific cell types are present in Lymph node | Sarcoidosis
Non-caseating Epithelioid Granulomas
29
What are the investigation need for the diagnosis of Sarcoidosis
``` Clinical findings Imaging findings - CXR Serum calcium levels angiotensin converting enzyme levels (high levels present in Sarcoidosis) Biopsy Pulmonary function test Spirometry ```
30
What is Hypersensitivity Pneumonitis
an inflammation of the alveoli within the lung caused by hypersensitivity to inhaled organic microorganism
31
What is examples of organisms that trigger Hypersensitivity Pneumonitis
Thermophilic actinomycetes - bacterium Bird / Animal proteins - faeces, bloom Fungi - Aspergillus spp Chemicals
32
Examples of Thermophilic actinomycetes are: - Micropolyspora faeni - Thermoactinomyces vulgaris What type of hypersensitivity pneumonitis does this cause
Farmers lung
33
Where would you find - Micropolyspora faeni - Thermoactinomyces vulgaris
Mouldy hay
34
What is the pathology of hypersensitivity pneumonitis that leads to disruption of diffusion and then respiratory failure
Inhalation of particle, which then deposits in the interstitium, disrupting the diffusion by creating an inflammatory reaction and lowering gas transfer
35
What is the signs and symptoms for acute hypersensitivity pneumonitis
Fever, dry cough, myalgia, Chills 4-9 hours after Ag exposure Crackles, tachyopnoea, wheeze Precipitating antibody
36
What is the main aetiology of hypersensitivity pneumonitis
causative antigens
37
What is the signs and symptoms of chronic hypersensitivity pneumonitis
Malaise, SOB, cough | Crackles and some wheeze
38
hypersensitivity pneumonitis is immune complex mediated by what hypersensitivity reactions
Type III and Type IV Hypersensitivity reaction
39
What cells are present in hypersensitivity pneumonitis
``` epithelioid granulomas Foamy histiocytes (macrophages laden with lipid) ```
40
Where is hypersensitivity pneumonitis located in the lungs
Upper zones - centriacinar
41
what can chronic hypersensitivity pneumonitis lead on to cause
Bronchiolitis obliterans - fixed airway obstruction
42
Why is hypersensitivity pneumonitis more likely to be an upper zone disease
as corresponds to inhalation of antigens as thats where the are more likely to deposit
43
interstitial pneumonitis UIP is a lung diseases characterised by
progressive scarring of both lungs (no granulomas)
44
What is the potential causes of interstitial pneumonitis UIP
Connective tissue diseases ; esp scleroderma and rheumatoid disease Drug reaction Post infection Industrial exposure - asbestos
45
What is the morphology of interstitial pneumonitis UIP
Patchy interstitial chronic inflammation proliferating fibroblastic foci Type 2 pneumocyte enlarge
46
What gives you the evidence if its an old or a recent injury
whether interstitial pneumonitis UIP is temporal or spatial
47
What is the general demographic of interstitial pneumonitis
Ages 50 above | More likely to be male >female
48
What is the clinical signs of interstitial pneumonitis
Dyspnoea, Cough, Basal Crackles, Cyanosis, Clubbing Progressive disease
49
What is used to investigate interstitial pneumonitis
Chest X ray Pulmonary function test - reduced gas transfer spirometry
50
What is the outcome of end stage interstitial pneumonitis
The lung tries to repair itself with cystic fibrosis but fails creating the appearance of a honeycomb lung
51
When is V/Q imbalance the lowest
In hypoxemia conditions | due to local alveolar hypoventilation due to some focal disease
52
What increases the V/Q ratio imbalance
increase even the slightest amount of oxygen breathed in (FIO2)
53
Restrictive disease affects diffusion in what two ways
Increase thickness and surface areas of membrane, increasing gas transfer time increase equilibration time above 0.25 seconds
54
What is the normal equilibration time?
0.25 seconds
55
What is the normal capillary transit time
0.75seconds
56
If restrictive lung diseases increases equilibration time, how does this create hypoxia
as equilibration time increases to the same time or more as capillary transit time, meaning there is not enough time to fully saturate RBC,
57
When can an increased equilibrium time cause problems
Its fine at rest, | when excise results in a decrease in PaO2
58
When Pa o2 falls it causes hypoxemia, what corrects hypoxemia and restores diffusion
corrected by increasing FIO2, which increase PA O2 again thus increasing the rate of diffusion
59
Why does a large shunt respond badly to increase in FI O2
Blood leaving normal lung is already 98% saturated
60
Why does CO2 levels increase in alveolar hypoventilation
lack of air moving in and out of the lungs leading to an imbalance in the alveolar CO2 levels – leads to retention of CO2 in arterial blood