Restrictive lung disease

Question 1

Explain a little about the interstitium of the lung (restrictive lung disease)

Answer 1

the connective tissue space around the airways and vessels and space between the basement membranes of the alveolar walls

In the normal alveolar wall, most of the alveolar epithelium (pneumocyte) and interstitial capillary endothelial cell basement membranes are in direct contact.

Question 2

what sort of process is largely (but not exclusively) involved in restrictive lung diseases?

Answer 2

inflammatory process

Question 3

Where is the principal location of restrictive lung diseases?

Answer 3

the interstitium of the lung

Question 4

what does restrictive lung disease mean with compliance?

Answer 4

reduced compliance - stiff lungs

Question 5

what does restrictive lung disease mean with Fev1/fev

Answer 5

low fev1 and low fvc but the fev1/fev ratio is normal

Question 6

what does restrictive lung disease mean with ventilation/perfusion

Answer 6

reduces gas transfer (Tco or Kco)- diffusion abnormality

ventilation/perfusion imbalance

when small airways affected by pathology

due to fibrous and inflammation tissue

Question 7

fev1/fvc figures in spirometry for restrictive lung disease

Answer 7

fev1 = 1.8Litres

fvc = 2.1 Litres

fev1/fvc 0.85

(normal woulf be fev1 = 4L fvc - 4.9L fev1/fvc = 0.91)

Question 8

Restrictive lung disease presentation

Answer 8

discover on an abnormal chest xray or ct scan

dyspnoea (short of breath on exertion, short of breath at rest as disease progresses)

respiratory failure type 1

heart failure

Question 9

in restrictive lung disease - explain the inflammatory process

Answer 9

diffuse interstitial lung disease > parenchymal (interstitial lung injury)

causes acute (which can become chronic) or chronic response.

chronic response:

unusual interstitial pneumonitis (ui); granulomatous response; other pattern

all end fibrosis - end-stage honeycomb lung.

Question 10

an acute inflammatory process for restrictive lung disease

Answer 10

diffuse alveolar damage (DAD)

diagnosis = acute interstitial pneumonia

Question 11

what is diffuse interstitial damage (dad) or acute interstitial pneumonia associated with

Answer 11

• major trauma - chemical injury (toxic inhalation) - circulatory shock - drugs - infection including viruses (influenza SARScov1 SARScov2) - auto(immune) disease - radiation - can be idiopathic

Question 12

Histology of diffuse acute damage syndrome DADS

Answer 12

protein-rich oedema fibrin hyalin membranes denuded basement membranes epithelial proliferation fibroblast proliferation scarring - interstitium and airspaces

Question 13

sarcoidosis

Answer 13

multisystem granulomatous disorder (unknown aetiology)

involving abnormal collections of inflammatory cells that form lumps (granulomata). The disease usually begins in the lungs, skin, or lymph nodes. Less commonly affected are the eyes, liver, heart, and brain. Any organ, however, can be affected.

Question 14

Histopathology of sarcoidosis

Answer 14

Epitheloid and giant cell granulomas

NOT necrosis/caseation very unusual

little lymphoid infiltrate

variable associated fibrosis

type 4 hypersensitivity reaction

RARELY PROGRESSES TO SIGNIFICANT FIBROSIS AS not type 3 reaction or chronic inflammatory reaction

Question 15

Sarcoidosis - incidence

Answer 15

multisystem disorder unknown origin

commonly affects young adults (females more than males)

3-4/1000 in Uk

20/100000 in African Americans in USA

low equatorial regions

a disease of temperature climates

Question 16

Sarcoidosis - what organs does it commonly involve

Answer 16

lymph nodes almost 100% cases lungs >90%

spleen 75% liver 70% skin, eyes, skeletal muscle 50% bone marrow 20%

saliva glands up to 50%

Question 17

presentation of sarcoidosis

Answer 17

1 yound adults: acute arthralgia (joint pain) erythema nodosum (tender red nodules on the anterior shins) bilateral hilar lymphadenopathy

2 indidental abnormal chest x-ray or ct scan with no symptoms

3 shortness of breath, cough and abnormal chest x-ray

Question 18

chest x-ray presentation of sarcoidosis

Answer 18

massive enlargement of hilar lymph nodes

Question 19

presentation ct for sarcoidosis

Answer 19

diffuse interstitial involvement in the lungs with granular lead to fibrosis = respiratory failure

Question 20

sarcoidosis - will it go away without treatment?

Answer 20

usually is a time-limiting disease

on the rare occasion it may need corticosteroids/

Question 21

getting a sarcoidosis diagnosis

Answer 21

often can be given a clinical diagnosis - does not need therapeutic intervention or pathological sample.

• imaging
• serum, calcium +++ and ACE
• biopsy

Question 22

hypersensitivity pneumonitis

Answer 22

thermophilic actinomycetes (farmers lung)(high-temperature aerobic bacteria which belong to the group actinomycetes) mycropolyspora faeni, thermoactinomycytes vulgaris

bird/animal proteins - faeces, bloom

fungi aspergillus spp

chemicals

others.

Question 23

A 48-year-old woman of African ethnicity presents to her family doctor complaining of a lump in her neck. She reports that the lump has been there for the past week and has not increased in size significantly. She denies any pain or swallowing difficulty. Her previous medical history is unremarkable, and she has never been admitted to the hospital before, except for a visit to the ophthalmologist last year for red-eye, which necessitated treatment with topical steroid drops. Upon examination, the doctor notices some red tender nodules on the patient’s shin but the patient says that these come and go and do not bother her much. A chest x-ray reveals bilateral hilar lymphadenopathy with no other significant findings. Which one of the following is usually associated with this patient’s condition?

Elevated angiotensin-converting enzyme levels

Hypocalcemia

Poor sleep

Exposure to silica

Pain in the small joints of the hand

Answer 23

This patient presented with the signs and symptoms suggestive of sarcoidosis. The diagnosis is supported by the symptoms of a neck lump, which is most likely to be an enlarged lymph node, as well as examination findings of tender nodules on the shin, which are called erythema nodosum. In addition, there is a history of red-eye necessitating treatment with steroids and sarcoidosis patients often have eye involvement in the form of uveitis. The chest X-ray findings confirm the presence of bilateral lymphadenopathy which is one of the findings in sarcoidosis. Angiotensin-converting enzyme levels are usually elevated in sarcoidosis and would further support a diagnosis of sarcoidosis.

Question 24

hypersensitivity pneumonitis presentation

acute

Answer 24

Acute presentation - fever; dry cough; myalgia; chills (4-9 hours after allergen exposure) crackles, tachypnoea, wheeze, precipitating antibody

Question 25

hypersensitivity pneumonitis presentation Chronic

Answer 25

insidious, malaise, shortness of breath, cough, low-grade illness, crackles and some wheeze. \*Can lead to respiratory failure gas transfer low = history is important\*

Question 26

histology of hypersensitivity pneumonitis

Answer 26

immune complex-mediated combines type 3 and 4 hypersensitivity **soft** centriacinar **epitheloid grnulomata** **interstitial pneumonitis** **foamy histiocytes** **bronchiolitis oblitirans** **upper zone disease.**

Question 27

Respiratory alkalosis Common causes

Answer 27

anxiety leading to hyperventilation pulmonary embolism salicylate poisoning\* CNS disorders: stroke, subarachnoid haemorrhage, encephalitis altitude pregnancy \*salicylate overdose leads to a mixed respiratory alkalosis and metabolic acidosis. Early stimulation of the respiratory centre leads to a respiratory alkalosis whilst later the direct acid effects of salicylates (combined with acute renal failure) may lead to an acidosis

Question 28

A 60-year-old man presents to his GP with a 10-day history of a productive cough and shortness of breath. His GP prescribes antibiotics. 1 week later his symptoms are not improving and he now has a persistent fever and pain on inspiration. The GP sends him for a chest x-ray which is suggestive of an empyema. What is the most likely causative organism? Mycobacterium tuberculosis Pneumocystis jirovecii Streptococcus pneumoniae Haemophilus influenzae Listeria monocytogenes

Answer 28

An empyema is a collection of pus in the pleural space. It is a potential complication of pneumonia and, in this case, is the cause of the gentleman's pleurisy. The commonest cause of empyema is Streptococcus pneumoniae, which is also the commonest cause of pneumonia.

Question 29

where does hypersensitivity pneumonitis usually begin?

Answer 29

centriacinar region this condition is associated with inhaled antigens - precipitated centriacinar region - laminar airflows converts to gas diffusion tiny particulate or macromolecular particles biopsy here.

Question 30

histology difference sarcoidoma and hyprsensitivity pneumonitis

Answer 30

granulomar in hypersensitivity pneumonitis tend to be softer and more diffuse in character granulomas - a chronic inflammatory process not seen in sarcoidosis alveolar walls around respiratory bronchioles subject to chronic inflammatory process

Question 31

which zone of the lung does hyperinflammatory pneumonitis tend to affect

Answer 31

upper zone due to inhaled antigens - clearance mechanisms in the upper parts of the lung. not as efficient in lower parts.

Question 32

idiopathic pulmonary fibrosis

Answer 32

connective tissue, drugs, asbestos, viruses pathological process present in lungs has PIF

Question 33

what is the fibrosis or end-stage of honeycomb lung circumstance

Answer 33

increased mortality or DADS can die within disease when acute

Question 34

what are conditions of usual interstitial pneumonitis (UIP)

Answer 34

idiopathic pulmonary fibrosis it is almost routine patients end up with end-stage honeycomb lung and die of that disease.

Question 35

pathology process of usual interstitial pneumonitis

Answer 35

maybe seen in **connective tissue diseases** - esp scleroderma and rheumatoid disease **drug reaction post-infection industrial exposure**asbestos others **most are idiopathic -** hence idiopathic pulmonary fibrosis (IPF) cryptogenic fibrosis alveolitis (CFA)

Question 36

Histopathology of usual interstitial pneumonitis

Answer 36

Patchy interstitial chronic inflammation - type 2 pneumocyte hyperplasia - smooth muscle and vascular proliferation - evidence of old and recent injury; temporal heterogeneity; spatial heterogeneity - proliferating fibroblastic foci

Question 37

idiopathic pulmonary fibrosis (usual interstitial pneumonitis) clinical indications

Answer 37

elderly \> 50-year-old. males more than females clinically shows as dyspnoea, cough, basal crackles, clubbing progressive disease: most die within 5 years Chest x-ray basal. posterior, diffuse infiltrates, cysts, ground glass Restrictive PFT (pulmonary function test) and reduced gas transfer poor prognosis: some fulminant some steroid responsive.

Question 38

usual interstitial pneumonitis

Answer 38

basal and posterior fibrosis with honeycombing this case is complicated by peripheral adenocarcinoma. can lead to cancer (adenocarcinoma)

Question 39

Normal pulmonary gas exchange processes

Answer 39

airflow in airways - bulk flow or air in large conducting airways +URT - flow = laminar or turbulent flow driven by the pressure difference (breathing muscles intercostal and diaphragm). beyond terminal bronchiole: diffusion the blood-air barrier HB affinity to 02 means blood leaving capillary bed is 98% saturated for FI02 of only 0.21 (21%)

Question 40

Abnormal pulmonary gas exchange Normal paO2 Normal paCO2

Answer 40

10. 5-13.5kPa 4. 8-6.0kPa

Question 41

parameters for Respiratory failure

Answer 41

Type 1 - Pao2 \<8kpa (paCO2 normal or low) type 2 (PaCO2 \>6.5 kPa (pao2 usually low)

Question 42

what %% of oxygen in air do we breathe in?

Answer 42

21%

Question 43

what is the saturation of haemoglobin we can measure in peripheral arterial blood?

Answer 43

98%

Question 44

what is fIo2

Answer 44

the fraction of inspired air that is oxygen e.g. 21% o2 so 0.21

Question 45

Four abnormal states associated with hypoxaemia are:

Answer 45

ventilation/perfusion imbalance (VQ) diffusion impairment alveolar hypoventilation shunt

Question 46

ventilation/perfusion imbalance (VQ mismatch):

Answer 46

normally breathing 5-litres per minute. cardiac is 4L/min so normal VQ is **4/5 or 0.8** low v/q is **commonest** cause of hypoxaemia encountered clinically. low v/q in some alveoli rises due to **local** alveolar hypoventilation due to **some focal** disease. **_hypoxaemia is due to low v/q responds well to even small increased in fio2_**

Question 47

WHAT IS SHUNT

Answer 47

blood that passes from the right side of the heart to left without contacting ventilated alveoli (gas exchange occurring) normally 2-4% shunt pathological shunt in AV malformation, congenital heart disease and PULMONARY DISEASE **large shunts _respond poorly_ to increase in Fio"** **blood leaving _normal_ lung is already 98% saturated**

Question 48

pneumonia: why hypoxaemia?

Answer 48

vq mismatch bronchitis/bronchopneumonia (some ventilation of abnormal alveoli) - not enough) overall measurement of o2 in blood falls shunt - severe bronchopneumonia - lobar pattern with large areas of consolidation

Question 49

explain ventilation in: bronchopneumonia shunt (e.g. lobar pneumonia)

Answer 49

**bronchopneumonia** = some ventilation, just not enough and you see 02 in the blood drop **shunt** = zero ventilation (lobar pneumonia) looks solid zero vent

Question 50

how is po02 by hypoventilation corrected by

Answer 50

raising fio2 arterial co2 will rise. the fall in o2 by hypoventilation corrected inspired air concentration of o2 fio2

Question 51

why may someone have alveolar hypoventilation

Answer 51

global phenomenon affecting all tissue upper airway or tracheal obstruction a mechanical problem with breathing (chest wall damage) functional problems with breathing mechanisms (muscle paralysis, diaphragm damage) neurological problems with breathing (peripheral nerve damage or loss of function) CNS malfunction - opiate poisoning,

Question 52

copd why hypoxaemia

Answer 52

v/q mismatch: airway obstruction +/- bronchopneumonia# diffusion impairment: loss of alveolar surface area in emphysema alveolar hypoventilation: reduces respiratory drive **shunt: only during acute exacerbatio**n if pneumonia is extensive enough.

Question 53

histology of normal alveolar wall and one thickened by interstitial infiltrate

Answer 53

the normal alveolar wall is virtually no alveolar membrane because made of a relative basement membrane of epithelial cell - gas can move through or between the cell and through the membrane. damaged alveolar tissue is much thicker making it harder for gas exchange (slower) inflammatory cells, fibrosis, fibroblasts

Question 54

in a normal human, what is the speed of 02 equilibrium and the average time a red blood cell spans the alveolar-capillary

Answer 54

0.25 for 02 to reach equilibrium and 0.75 seconds on average for reb blood cell spans alveolar capillary network

Question 55

in disease how long may it take for 02 to reach equilibration?

Answer 55

closer to the 0.75 seconds which is the entire time it takes for a red blood cell to transit the capillary network 0.75 IS CIRCULATION **AT REST** the red cell time falls in exercise = hypoxaemia during exercise.

Question 56

restrictive disease what is the physiological definition

Answer 56

forced vital capacity \< 80%

Question 57

what are the causes of restrictive disease

Answer 57

**lung -** interstitial lung disease (idiopathic pulmonary fibrosis) (sarcoidosis)(hypersensitivity pneumonitis) **pleura -** (pleural effusion)(pneumothorax) (pleural thickening) **nerve or mucle -** (amuotrophic lateral sclerosis) **bone -** kyphoscoliosis (alkylosis spondylitis) (thoracoplasty)(rib fractures) **subdiaphragmatic causes** obesity, pregnancy

Question 58

key causes/conditions of restrictive lung disease

Answer 58

Pulmonary fibrosis Asbestosis Sarcoidosis Acute respiratory distress syndrome Infant respiratory distress syndrome Kyphoscoliosis e.g. ankylosing spondylitis Neuromuscular disorders Severe obesity

Question 59

restrictive lung disease spirometry features

Answer 59

FEV1 - reduced FVC - significantly reduced FEV1% (FEV1/FVC) - normal or increased

Question 60

spirometry features of obstructive disease

Answer 60

FEV1 - significantly reduced FVC - reduced or normal FEV1% (FEV1/FVC) - reduced

Question 61

obstructive lung diseases

Answer 61

## Footnote Asthma COPD Bronchiectasis Bronchiolitis obliterans

Question 62

where is the interstitium?

Answer 62

the space between the epithelium side of the alveolus and the endothelium of the capilarry in picture you see normal alveolus and thin membrane - the right is very thickened breathless patient

Question 63

what are interstitial lung diseases and what can this result in?

Answer 63

over 200 diseases causing thickening of interstitium can result in **_pulmonary fibrosis_**

Question 64

Sarcoidosis what is a histological hallmark?

Answer 64

multi granulomatous disease unknown cause - **_non-ceasating granuloma_** (looks like ceasating cheese)

Question 65

who often gets sarcoidosis

Answer 65

\<40 adults women more than men you can catch it world-wide

Question 66

how to investigate for dsarcoidosis

Answer 66

take history chest x-ray (chest x-ray swelling of glands hilum)

Question 67

how to investigate for sarcoidosis

Answer 67

pulmonary function test bloods/urinalysis/ ecg/ tb skin test/ eye exam further assess bronchoscopy transbronchial biopsy

Question 68

other ways to get a biopsy for sarcoidosis

Answer 68

less commonly done now, usually diagnosed through glands may need mediastinoscopy video-assisted thoracoscopic lung biopsy (VATS).

Question 69

do chest extrays affect prognosis for those with sarcoidosis?

Answer 69

can stage 1 to 4

Question 70

how to treat mild sarcoidosis

Answer 70

mild - no vital organ involvement, normal lung function, few symptoms no treatment needed

Question 71

in sarcoidosis if you present with sore joints and lumpy red legs treatment

Answer 71

with erythema nodosum/arthralgia - treat with NSAIDs

Question 72

in sarcoidosis if you have skin leisions, anterior uveitis or cough treatment

Answer 72

topical steroids

Question 73

in sarcoidosis, if you present with cardiac, neurological, eye disease not responding to topical treatment or hypercalcaemia treatment

Answer 73

systemic steroids

Question 74

idiopathic pulmonary fibrosis histological difference

Answer 74

fibroblastic focus (small area)

Question 75

typical presentation idiopathic pulmonary fibrosis

Answer 75

chronic breathlessness and cough typically in 60-70-year-olds more common in men failed treatment for left ventricular failure or infection clubbed fingers and crackles

Question 76

xray presentation in idiopathic pulmonary fibrosis

Answer 76

non-specific shadowing at the base. a hint of sternotomy wired could indicate cardiac surgery so past of? LVF indicator for IPF developing

Question 77

treatment options for idiopathic pulmonary fibrosis

Answer 77

median survival 3 years refer to IDL clinic medical option OAF (oral antifibrotic) pirfenidone, nintedanib, palliative care. surgical option - transplant

Question 78

hypersensitive pneumonitis - what can cause

Answer 78

exposure to antigen hypersensitivity 4 farmer lung, whisky buildings yeast, birds

Question 79

in sleep apnea where is the obstruction mainly?

Answer 79

between base tongue soft palet and posterior pharyngeal wall

Question 80

sleep apnea is associates with what other comorbidities?

Answer 80

hypertension, increased risk of stroke and likely increase risk of heart disease

Question 81

prevelance

Answer 81

affects more men than women

Question 82

diagnosing sleep apnea

Answer 82

history questionnaire overnight sleep study pulse oximetry limit sleep study and full polysonogrophy

Question 83

sleep apnea OSA severity

Answer 83

desaturation rate (AHI) 0-5 normal 5-15 mild 15-30 moderate \>30 severe

Question 84

treatment for sleep apnoea

Answer 84

weight reduction avoid alcohol diagnose and treat endocrine disorders (hypothyroidism, acromegaly) - continuous positive airway pressure (CPAP) mandibular repositioning splint

Question 85

treatment for narcolepsy

Answer 85

modafinil dexamphetamine venlafaxine (for cataplexy) sodium oxybate (xyrem)

Question 86

Chronic ventilarotu failure is defined by ABG -

Answer 86

elevated pco2 (\>6.0kPa\_ pos \<8kPa normal blood Ph elevated bicarbonate

Question 87

aesthenia gravis is associated with thyroid tumours. Select one: True False

Answer 87

False – myasthenia gravis is associated with thymus tumours. Anybody with a new diagnosis of MG will undergo investigation for thymus tumour, and many of these people will end up having surgery.

Question 88

Patients with cystic fibrosis can undergo single or double-lung transplant. Select one: True False

Answer 88

False – if patients with CF receive a lung transplant, it must be a double lung transplant. This is because it is a condition that carries a high risk of recurrent infection, to which the transplanted lung would also be susceptible if a native lung were left in situ.

Question 89

Steroids are given to mothers going into preterm labour to speed up foetal lung development. Select one: True False

Answer 89

True – steroids stimulate surfactant production, so mothers who go into labour prematurely are given steroids to reduce the risk of the baby having respiratory distress syndrome.

Question 90

Hypersensitivity pneumonitis predominantly affects the apices. Select one: True False

Answer 90

True – most (but not all) lung diseases caused by inhaled antigens will predominantly affect the upper regions of the lungs.

Question 91

The embryonic lung buds are derived from the foregut. Select one: True False

Answer 91

True – the lungs begin as an outpouching of the foregut, hence the close proximity of the trachea to the oesophagus.