ICL 2.11: Restrictive Lung Diseases

Question 1

what is restrictive lung disease?

Answer 1

anything that can decrease lung volume! specifically decreased TLC, FVC and FEV1

since everything decreases, FEV1/FVC will be normal, over 0.80

Question 2

what are the 2 major causes of restrictive lung disease?

Answer 2

1. extra-pulmonary causes
   - lots of fat around the lungs like obesity

• kyphoscoliosis
• pleural effusion = fluid in the pleura
  2. interstitial lung disease = restrictive lung disease secondary to lung disease

Question 3

what are the effects of extra-pulmonary restrictive lung disease on A-a gradient, residual volume, and DLCO?

Answer 3

normal A-a gradient

normal residual volume

normal DLCO

these are all normal because the restrictive lung disease is being caused by something extra pulmonary, there’s nothing actually wrong with the lung itself

Question 4

what are the effects of interstitial restrictive lung disease on A-a gradient, residual volume, and DLCO?

Answer 4

increased A-a gradient

decreased residual volume

decreased DLCO

Question 5

what conditions can cause extrapulmonary restrictive lung disease?

Answer 5

1. poliomyelitis
2. myasthenia gravis
3. obesity
4. scoliosis

Question 6

what conditions can cause interstitial restrictive lung disease?

Answer 6

1. collagen vascular disease
2. sarcoidosis
3. pneumoconiosis (asbestosis, coal miner, silicosis)
4. hypersensitivity pneumonitis
5. drug toxicity
6. idiopathic

Question 7

what is interstitium?

Answer 7

the connective tissue framework of the lung!

the secondary pulmonary lobule is the most important part of the interstitium because it has lymphatics which clean stuff up which is why when you have interstitial restrictive pulmonary disease you’re in big trouble if you get an infection and the pneumonia will last longer and be more severe without the lymphatics around to clean stuff up

Question 8

what is the secondary pulmonary lobule?

Answer 8

part of the interstitum: a unit of the lung supplied by 3-5 terminal bronchioles

it has airways, pulmonary arteries, veins and lymphatics

lymphatics clean debris and pus like when there’s pneumonia

when there’s interstitial lung disease, this part of the lung is damaged which is bad because it’s what cleans up infections and without it you’re screwed and very susceptible to infections

Question 9

what are interstitial lung diseases?

Answer 9

disease of the connective tissue framework of the lung

it will effect the interlobular septae

Question 10

what are airspace diseases?

Answer 10

diseases that affect the terminal airspaces = alveoli!

the alveoli can be filled with pus, blood, edema, cells –> the gas in the alveoli is replaced by another substance!

this will cause white infiltrates on CXR

Question 11

how do we physiologically measure the abnormalities in interstitial lung disease?

Answer 11

check the diffusing capacity for carbon monoxide (DLCO)

the expectation is that it’ll be at least 80% of what’s predicted for that specific patient

you ask the patient to breath in CO and then ask them to hold their breath for 10 seconds to allow for diffusion and then you measure the amount of diffusion

this tells you the ability of the lungs to transfer gas across the alveolar-capillary membrane to RBCs –> you need to know your Hb levels because they can skew the results

Question 12

how does DLCO differentiate extrapulmonary vs pulmonary restrictive lung disease?

Answer 12

if you have extrapulmonary restrictive lung disease you’ll have a normal DLCO because there’s nothing wrong with the lung itself

but if you have interstitial lung disease you’ll have decreased DLCO!

Question 13

what is ground glass opacity?

Answer 13

hazey looking lungs but you can still see through it so it doesn’t obscure underlying vessels

the lungs just look a little cloudy white

this tells us there’s alveolitis or early fluid buildup that’s not totally filling the alveoli yet

you see this with interstitial diseases

Question 14

what is honey combing on CT?

Answer 14

late stage lung fibrosis

honey comb fibrosis is very extensive and can cause traction bronchiectasis = they’re pulled open by the fibrosis causing the honey comb appearance!

Question 15

what is tree in the bud appearance on a CT?

Answer 15

when the bronchioles are obstructed with pus! the CT literally looks like tree branches with buds

so it’s associated with bronchiolar infection like infectious brochiolitis

ex. mycobacterium, staph, etc.

Question 16

what testing do you do if you suspect interstitial lung disease?

Answer 16

if someone comes in with SOB and you do a CXR that isn’t that sensitive but you hear crackles so next you should:

1. high resolution CT
2. physiologic testing (DLCO and PFT; RV will be decreased)
3. bronchoalveolar lavage (BAL)
4. surgical biopsy

Question 17

what is the investigation of choice for detection and characterization of interstitial lung disease?

Answer 17

high resolution CT scan is the most sensitive and specific

MRI is only used for abnormalities in the apex of the lungs where we want to see the involvement of the brachial plexus like with a Pancost tumor

CXR aren’t very sensitive

ventilations perfusion scans are for chronic thromboembolic disease

Question 18

what is the physiologic response of the lungs to interstitial lung disease?

Answer 18

1. restrictive pattern (decreased FVC)

2. impaired gas exchange (decreased DLCO)

Question 19

pulmonary funciton abnormalities in interstitial lung diseases include all of the following except?

A. reduced vital capacity

B. reduced FEV1/FVC

C. reduced diffusion capacity

D. reduced total lung capacity

Answer 19

B. reduced FEV1/FVC

because all the values are proportionally reduced so this ratio won’t change and it’ll still be over 0.8

Question 20

which conditions are collagen vascular disease ILD?

Answer 20

1. scleroderma
2. polymyositis-dermatomyositis
3. SLE
4. RA
5. mixed connective tissue disease
6. ankylosing spondylitis

Question 21

what is rheumatoid arthritis?

Answer 21

disease of the joints that effects women more than men but when it comes to the lungs it effects male lungs more

can cause collagen vascular disease ILD!

high titers of RF and rheumatoid nodules will be present

Question 22

what is scleroderma?

Answer 22

disease that can cause collagen vascular disease ILD

associated with honeycombing with traction bronchiectasis

scleroderma can also cause esophagus dilation which causes aspiration!!

Question 23

what is sarcoidosis?

Answer 23

asystemicdiseasecharacterize bythepresenceofnoncaseatinggranulomasthat is systemic so it can literally effect any organ but most commonly the skin, liver and lungs

sarcoidosistypicallyaffectsyoungadults,butitcanaffectanyindividualatanyage.

theexactetiologyisunknown….

itmostcommonlyaffectsthepulmonarysystem,initialpulmonarysymptomssuchascough

afterpulmonaryinvolvement,theeyesandskinarethenextmostcommonlyinvolvedsystems

Question 24

what is the pathologenesis of sarcoidosis?

Answer 24

the hallmarkofsarcoidosisisthepresenceofnoncaseatinggranulomasinaffectedorgans

thesegranulomasformbecauseofwidespreadactivationofCD4+/CD8+Tcellsandthereleaseofpro‐inflammatorycytokinesbyTh1CD4+Tcells

thereleaseofinterferon(IFN)‐γfromCD4+Tcells activatesmacrophages which thenproducetumornecrosisfactor(TNF)‐αthatmaintainsthegranulomas

the activated macrophages withinthesegranulomasproduceangiotensinconvertingenzyme(ACE),someasuring serumACElevelsisapartofthework‐upforsarcoidosis however, it’s NOT specific

Question 25

what is the clinical presentation of pulmonary sarcoidosis?

Answer 25

1. young adults
2. cough
3. SOB
4. chest pain
5. decreased total lung capacity
6. normal FEV1/FVC
7. CXR: bilateral hilar adenopathy and reticular opacities

patients are often found to have interstitial lung disease

Question 26

what is Lofgren syndrome?

Answer 26

a specific acute clinical presentation of sarcoidosis, consisting of a classic triad:

fever + bilateral symmetrical hilar lymphadenopathy + erythema nodosum

Question 27

what is the clinical presentation of the various organs that can be effected by sarcoidosis?

Answer 27

1. skin lupus like rash
2. messed up pupil
3. nerves = Bells palsy
4. lung nodules

lung, skin, liver and eyes are most effected

Question 28

what is the prognosis for pulmonary sarcoidosis? how do you treat it?

Answer 28

steroids!

they act as immunosuppressants and are the DOC for sarcoidosis

70% of patients will have total remission, 20% will have some permanent loss of lung function

10% will die due to cardiac dysfunction due to AV block, CNS disease, or pulmonary fibrosis leading to cor pulmonale

Question 29

A 24-year-old African American male applies for work in a steel mill. He has a negative health history and a normal review of systems. A routine CXR is performed and shows bilateral adenopathy

A. order a contrasted CT of the chest, abdomen, and pelvis

B. clear to start work on Monday

C. collect 3 sputum samples for acid-fast smears and cultures, and send one sample for Mycobacterium tuberculosis nucleic acid amplification

D. order high-resolution CT scan of the chest without contrast

E. start prednisone 60 mg daily

Answer 29

no crackles and totally normal CXR except for hilarity adenopathy so he can go back to work! he has no physiological disease

not all cases of sarcoidosis need to be treated unless there’s organ involvement or symptoms; then you’d give steroids

Question 30

what is pneumoconiosis?

Answer 30

aninterstitiallungdisease
resultingfroman inflammatoryresponsethat
occurswhencertaintypesofdust particlesareinhaled

it’s an occupational and environmental lung disease caused by exposure

common ones are coalminers disease, silicosis and asbestos related diseases

Question 31

inhalationofwhatsizedparticlesismostlikelytoleadtothe developmentofpneumoconiosis?

Answer 31

inhalationofparticlesthatare1‐5µmindiameterismostlikelyto leadtothedevelopmentofpneumoconiosis

the smaller the particle the deeper down into the lung the particles can get

Question 32

what is the pathogenesis of pneumoconiosis?

Answer 32

chronic exposure to small particles 1‐5µm that get deep down into the lungs and the immunological response causes inflammation which damages the lungs over time

Question 33

what is the most helpful tool in the diagnostic workup of someone with suspected pneumoconiosis?

Answer 33

employment details and exposure history!!

1. job
2. type of industry
3. years employed
4. materials used by workers
5. hygiene of workplace
6. ventilation/exhaust system
7. use of protection

Question 34

what is coal miner’s lung?

Answer 34

a type of pneumoconiosis

coal is an inert dust BUT extended exposure over the course of many years causes pneumoconiosis to develop

prolongedexposuretocoalleadstopulmonarymacrophagesbecomingfilledwithcarbon,knownascarbon‐ladenmacrophages

CXR ofapatientwithcoalworkers’pneumoconiosiswillshowthatbothoftheupperlobes havebeenaffected because upper lobes have the highest ventilation

Question 35

whatisthehistologichallmarkinapatientwithcoalworkers’ pneumoconiosis?

Answer 35

carbon‐ladenmacrophagesisthe
histologic hallmarkofcoalworkers’
pneumoconiosis

Question 36

what is silicosis?

Answer 36

a pneumoconiosis that results from the inhalation of silica dust

patients usually have h/o working in foundries as sand blasters or in mines

Question 37

what are patients with silicosis at risk for?

Answer 37

tuberculosis!

today it’s HIV is the highest risk for tuberculosis but in south africa, it’s silicosis!

silicosis also increases your list for lung cancer

Question 38

what is the imagining hallmark of silicosis?

Answer 38

“eggshell”calcificationsareseeninthehilarlymphnodesofthechest

silicosisisknown toaffecttheupperlobesofthelungs

Question 39

what are the risk factors for silicosis?

Answer 39

1. mining
2. stone cutting
3. road and building construction

4 .glass manufacturing

5. sand blasting
6. sculpting or glass blowing

Question 40

what is Caplan syndrome?

Answer 40

RA + pneumoconiosis of any type

cough, SOB, features of RA like painful joints and morning stiffness

Question 41

what is asbestos?

Answer 41

asbestos refers to six naturally occurring fibrous minerals that have the ability to resist heat, fire and electricity

SO much industrial stuff used to use asbestos because it’s heat proof!

Question 42

what is asbestosis?

Answer 42

a chronic, progressive form of parenchymal interstitial fibrosis caused by long term asbestos exposure that usually effects the lower lobes

lungs will have pleural plaques

increased risk for malignant mesothelioma

increased risk for lung cancer

patients will often have h/o working in shipbuilding, roofing, or plumbing industries

Question 43

what is a common CXR finding of a patient with asbestosis?

Answer 43

1. pleural effusions

2. subdiaphragmatic pleural plaques

Question 44

what is the treatment for pneumoconiosis?

Answer 44

it can’t be cured…

progression can be slowed though with treatment

most importantly, avoid exposure to the offending agent and take preventative measures like quit smoking and wear PPE

Question 45

what is mesothelioma?

Answer 45

this aggressive cancer forms in the thin membrane (mesothelium) that protects vital organs in the chest and abdomen

exposure to asbestos is the only medically-verified cause of the disease

Question 46

what is hypersensitivity pneumonitis?

Answer 46

an inflammatory lung disease caused by an immunologic response to inhaled environmental exposures

it’s a type III and IV hypersensitivity reaction

can be caused by fungi, bacteria, animal products, bird poop, and chemicals –> the most common is thermophilic actinomycetes which is associated with cool mist humidifiers

it will cause noncaseating granulomas that will result in interstitial lung disease

Question 47

what are the acute clinical findings seen with hypersensitivity pneumonitis?

Answer 47

1. abrupt onset = 4-6 hours following exposure
2. fevers, chills, malaise, nausea, cough, chest tightness, dyspnea without wheezing

can be confused with oral or bacterial infection so patients are frequently treated with antibiotics initially

Question 48

what are the chronic clinical findings seen with hypersensitivity pneumonitis?

Answer 48

continued exposure to triggers

you might not always have a history of acute episodes to lead you in the right direction

but patients will often report insidious onset of cough, dyspnea, fatigue and weight loss

maybe try to ask about their history of where they work, if they have birds, etc.

Question 49

how do you treat hypersensitivity pneumonitis?

Answer 49

avoid the antigen!!

systemic steroids can be given to help with short-term recovery from symptoms

Question 50

what is idiopathic pulmonary fibrosis?

Answer 50

chronic, progressive disorder leading to fibrosis/scarring of the lower respiratory tract

you’ll see irregular reticular opacities and traction bronchiectasis that will appear as honeycombing on CT

2-5 year survival

it’s a restrictive disease so FEV1/FVC will be above 0.8

Question 51

how do you treat idiopathic pulmonary fibrosis?

Answer 51

1. supportive care like oxygen
2. vaccination against pneumococcal and influenza
3. lung transplant is the only definitive treatment

no medication can cure IPF but there’s 2 medications that slow progression: nintedanib and pirfenidone

Question 52

which drugs are toxic to the lungs?

Answer 52

1. nitrofurantoin (antibiotic)
2. amiodarone (anti arrhythmic)
3. gold (anti-inflammatory)
4. bleomycin (chemo)
5. radiation