DPLD, Resp Physiology, Transplant Flashcards
CHEST Videos, SEEK questions
Respiratory pressure associated with
(a) Inspiratory pressure associated with hypercapnia
(b) Weak cough/difficulty clearing secretions
(a) Max inspiratory pressure under (1/3) predicted normal associated with hypercapnia
(b) Weak cough expected with max expiratory pressure under 60
Most sensitive lung volume for obesity
ERV = expiratory reserve volume (amount you can exhale more after tidal volume exhalation)
Which lung volume decreases with age?
(a) Why does TLC remain the same?
(b) FEV1 reduction
Lung volumes with age- vital capacity reduces (inspiratory reserve volume + tidal volume + expiratory reserve volume) but residual volume increases
(a) TLC RTS because even though VC reduces, RV increases
(b) FEV1 reduces by 30 ml per year after age 30
What correlates with good DLCO maneuver?
(a) Inspired volume
(b) Duration of breath hold
Good DLCO maneuver
(a) Inspired volume at least 90% of vital capacity (TV + ERV + IRV)
(b) At least 10 second breath hold
Which drugs to hold before methacholine challenge?
Hold LAMA for at least a week
What is considered a positive methacholine challenge?
20% reduction in FEV1 from escalating doses of methacholine (up to 400 ug)
Who to consider for hypoxia altitude simulation testing?
PO2 lower at higher altitude- consider testing in pts with SpO2 under 92% correlating to PaO2 under 70
Minimal clinical importance difference for 6MWT
30m = minimal important difference for 6MWT
Which system is the limiting step for exercise in most healthy ppl?
Cardiovascular system (HR and stroke volume)
Not limited by vital capacity, in fact should have respiratory reserve (normal flow-volume loop, not at max MV) and normal gas exchange (no desat)
Desat of more than 5% from baseline is abnormal
What is the clinical diagnosis that fits the lung injury pattern of
(a) UIP
(b) DAD
Histologic pattern of
(a) UIP
If has a cause: CTD, asbestos, chronic HP, genetic disorders (ex: Hermansky-Pudlak syndrome)
If idiopathic = IPF
(b) Diffuse alveolar damage is the histologic finding of ARDS
If has a cause: infection, drugs, radiation
If doesn’t have a cause = AIP (acute interstitial PNA)
BAL findings characteristic of
(a) NSIP
(b) OP
(c) PLCH
BAL cells
Normal: 85% macrophages, 10-15% lymphocytes (slow immune cells, adaptive immune response), under 3% neutrophils (acute inflammation, innate immune response), under 1% eos
(a) NSIP = nonspecific interstitial PNA
over 20% lymphocytes, ‘BAL lymphocytosis’
(b) OP = mixed but high lymphocytes (20-40%) and neutrophils 10%, can have eos 5%
(c) PLCH pathognomonic- positive CD1a stain
Describe radiographic features of typical UIP
Radiographic features of UIP
-subpleural and basilar predominance
-reticular changes, bronchiectasis
-basilar honeycombing
-absence of other findings like ground glass or nodules (more c/w NSIP)
Describe histologic features of UIP
Histologic features that makes UIP
-fibroblast foci
-heterogeneity: normal lung next to fibrotic (homogenous more NSIP)- ‘patchy’ involvement
-basilar and peripheral predominant (as correlated on imaging)
-architectural distortion, honeycombing
-no features suggesting alternate diagnosis (granulomas)
NSIP
(a) Radiographic findings
(b) BAL findings
(c) Prognosis compared to IPF
NSIP
(a) Radiographically- ground glass, absence of honeycombing, possibly subpleural sparing
(b) BAL lymphocytosis (over 20%, when under 10% is nromal)
(c) Better prognosis than IPF in general, more likely to respond to steroids
How we subtype NSIP
NSIP now subtyped as
-cellular
-fibrotic
Normal BAL cell pattern
Normal BAL cell pattern
85% macrophages
10-15% lymphocytes (slower immune response, adaptive immune response)
Under 3% neutrophils (fast immune response, innate immune response)
Under 1% eos
Expect lymphocytic or neutrophilic BAL cell pattern in:
(a) IPF
(b) sarcoidosis
(c) NSIP
(d) ARDS
BAL cell pattern
(a) IPF- neutrophilic
(b) Sarcoidosis- lymphocytic (then CD4/8 elevated)
(c) NSIP- lymphocytosis (over 20%, normal under 10%)
(d) ARDS- neutrophilic (more acute inflammatory cells)
Differentiate histology of IPF from NSIP
Histologically
IPF- fibroblast foci, temporal heterogeneity (normal lung dispersed with fibrosis). subpleural/basilar predominance
NSIP- homogeneous, can have more cellular (inflammatory, lymphocytic) or fibrotic subtype
Expect lymphocytic or neutrophilic BAL cell pattern in:
(a) OP
(b) Fibrotic HP
(c) Infection
BAL pattern
(a) Organizing PNA- lymphocytic (slower inflammatory cells, adaptive immune response)
(b) Fibrotic HP- lymphocytic
(c) Infection: neutrophils (acute inflammatory cells, innate immune response)
Definition of IPF acute exacerbation
(a) Tx
Worsening symptoms/hypoxia with worsening infiltrates for up to 1 month without another cause (really exclude cardiac-induced pulmonary edema)
(a) No tx just supporitve
-anti-fibrotics to try to reduce incidence
Proven role of antifibrotics
Antifibrotics- both nintedanib and pirfenidone most strongly shown to reduce decline in lung function (specifically FVC)
-probably reduces exacerbations
Mechanism of nintedanib vs. pirfenidone
Nintedanib- TKI- blocks receptors of tyrosine kinases used in fibroblastic growth
Pirfenidone- anti-TGFbeta
Side effect profile nintedanib vs. pirfenidone
(a) Labs to monitor
Nintedanib- diarrhea
Pirfenidone- rash, nausea
(a) For both- baseline LFTs and LFTs q1-3 months
Hereditary syndrome with subtypes causing IPF with albinism and bleeding
Hermansky-Pudlak syndrome = autosomal recessive defect in lysosomes (intracellular protein trafficking)
Albinism (hair, skin)
Increased bleeding risk
Progressive pulmonary fibrosis, typically IPF pattern, in certain subtypes
Aside from antifibrotics- other helpful mgmt tips in IPF patients
IPF management
-consider transplant
-GERD management: very high overlap even if asymptomatic
Differentiate OP and COP
Organizing pneumonia- histologic pattern (granulation tissue plugs, patchy) can be seen in multiple clinical entities: CTD, vasculitis, infection
If idiopathic OP pattern = COP clinically
Histology buzzwords
(a) fibroblastic foci
(b) granulation tissue plugs
(c) hyaline membranes
(d) pigmented macrophages
(e) congo red stain
(a) Fibroblastic foci = UIP
(b) granulation tissue plugs = organizing pneumonia
(c) hyaline membranes = DAD
(d) pigmented (smoker’s macrophages) in RB-ILD and DIP
(e) Congo red stain = amyloid deposits
Most common cause of histologic pattern of DAD
(a) When is it called AIP
Histologic pattern of DAD (hyaline membranes, granulation, fibroproliferative) correlates with the clinical syndrome ARDS, most common overall due to infection, next from drugs
(a) If idiopathic then = AIP (acute interstitial pneumonitis)
What is LIP?
(a) Common secondary causes
(b) Treatment
LIP = lymphocytic interstitial PNA- type of interstitial PNA with lymphocytic infiltrate
(a) HIV, Sjogrens most common, CVID or hypogammaglobulinemia
(b) ART (if HIV), steroids, immunosuppression
If histologic diagnosis of LIP made on lung biopsy- what lab tests to check?
LIP on surgical biopsy, should trigger checking
-HIV status (secondary LIP)
-Anti-Ro/La (SSA/SSB)- Sjogrens can cause secondary LIP
-RF and ANA (other CTDs)
HRCT findings of LIP
HRCT findings of lymphocytic interstitial pneumonia (can be idiopathic or due to HIV, Sjogrens):
-ground glass can be similar to NSIP
-thin-walled cysts (differs from NSIP)
-septal thickening
Key to differentiate LIP from pulmonary lymphoma
Key in LIP (lymphocytic interstitial PNA) is that the lymphocytes are polyclonal/benign
Clinical significance of CD4/8 ratio
-reduced ratio (under 1) correlates with organizing PNA
-higher, specifically over 4 rather specific for sarcoidosis
Interstitial pneumonia associated with immunodeficiencies (CVID, hypogammaglobulinemia)
LIP (lymphocytic interstitial PNA)- patchy GGOs, nodules and cysts on imaging, lymphoid infiltrates on histology
Differentiate AFOP from DAD histologically
AFOP- another rare idiopathic pneumonia (like LIP and PPFE)
Fibrinous balls associated with organizing PNA (OP with granulation tissue plugs) but no hyaline membranes (charateristic of DAD).
Also AFOP more distal- terminal bronchioles and alveoli while DAD involves all aspects of parenchyma)
What is pleuroparenchymal pulmonary fibrosis?
PPFE and LIP- two rare forms of idiopathic interstitial pneumonias
PPFE- fibrosis of upper-lobe pleura and subpleural parenchyma
pleural thickening
upper lobe volume loss
very prone to PTX
Organizing pneumonia
(a) Typical HRCT findings
(b) Treatment
OP
(a) patchy, fleeting ground glass or consolidative infiltrates
(b) Long-term steroids (6-12 months) with risk of recurrence if taper too quickly
Hamman-Rich syndrome
(a) Clinically
(b) What differentiates from ARDS
(c) Biopsy findings
Hamman-Rich syndrome = acute interstitial pneumonia (AIP)
(a) Clinically- acute hypoxic RF, rapid progression to respiratory failure (less than 7 days)
(b) Idiopathic, if isn’t idiopathic can call it ARDS
(c) Diffuse alveolar pattern on histo (same as ARDS)- diffuse hyaline membranes and alveolar architectural distortion
Histologic defining feature of respiratory bronchiolitis
(a) When becomes RB-ILD
Respiratory bronchiolitis = tan-pigmented (‘smokers’) macrophages in respiratory bronchioles (smallest airways partially surrounded by alveoli, differentiated from alveolar ducts which are fully surrounded by alveoli)
(a) Becomes RB-ILD when there’s clinical evidence of ILD in a smoker with no other pathologic finding
Differentiate RB-ILD from
(a) PLCH
(b) NSIP
(c) IPF
(d) DIP
(e) HP
RB-ILD
(a) PLCH- both associated w/ cigarette smoking with nodules but PLCH has upper lung zone cysts with honeycomb changes. Key is CD1a+ Langerhand cells in BAL for PLCH
(b) NSIP- basilar reticular and ground glass changes (vs. upper centrilobular changes of RB-ILD)
(c) IPF- honeycombing, no honeycombing in RB-ILD
(d) DIP- spectrum of same process but DIP more diffuse (vs. centrilobular in RB-ILD) with lower lobe predilection (vs. upper lobe for RB-ILD). Path is the differentiator
(e) HP- poorly formed noncaseating granulomas or mononuclear infiltrates
RB-ILD
(a) Typical imaging findings
(b) Typical PFT findings
RB-ILD
(a) Imaging- vague nodules, patchy GGOs due to smokers macrophages in and around respiratory bronchioles
(b) Mixed restrictive and obstructive
How to differentiate LIP from follicular bronchiolitis
Hard b/c both are on the spectrum of lymphoproliferative pulmonary diseases, associated with Sjogrens and immunodeficiences (CVID, HIV) but do have different path and imaging
LIP = Lymphoid interstitial PNA- cysts on imaging
LIP path- mix of cells (lymphocytes, plasma cells, histiocytes
FB- hyperplastic lymphoid follicles with germinal centers (but no plasma cells)
CTD-related ILDS
(a) Most common pattern overall
(b) Most common pattern in RA
CTD-related ILDs
(a) Overall most common: NSIP
(b) In RA specifically UIP is most common
Antibody in the following associated with higher risk of ILD
(a) Anti-synthetase syndrome
(b) Systemic sclerosis
(a) Anti-JO = anti-tRNA synthetase
Anti-synthetase = subset of polymyositis/dermatomyositis spectrum
(b) Anti-SCl70 (topoisomerase-1 Ab) associated with higher risk of ILD
CTD related to increase risk of primary pulmonary lymphoma
Sjogrens- think of association with lymphocytic spectrum of diseases (follicular bronchiolitis, lymphoid interstitial PNA) and primary pulmonary lymphoma = MALToma
For which CTD-ILD would steroids not be first line treatment?
(a) And what is first line treatment
Systemic sclerosis specifically MMF (mycophenolate mofetil = cellcept) has good data
Then if fibrosis persists after MMF initiation can consider adding nintedanib
BAL findings consistent with sarcoidosis
Sarcoidosis BAL: lymphocytic (over 15%)
CD4/CD8 high, specifically over 4 (vs. low c/w organizing PNA and HP)
Stages of sarcoidosis based on chest imaging
(a) Why stage like this?
Stages of sarcoidosis
0- no lung involvement (8% at time of diagnosis)
I- bilateral hilar adenopathy withOUT parenchymal involvement (40%)
II- bilateral hilar LN with parenchymal involvement (35%)
III- parenchymal involvement w/o hilar lymphadenopathy (10%)
IV- progressive fibrosis with/without cavitation (5%)
(a) Radiographic stage correlates with rate of spontaneous remission
Which drug is typically first-line steroid sparing agent for sarcoidosis?
Methotrexate
Clinical features of Lofgren’s syndrome
Lofgren’s syndrome = triad of arthritis (most commonly bilateral ankes), erythema nodosum, and bilateral hilar lymphadenopathy
-Diagnostic for sarcoid with high rate of spontaneous remission (so doesn’t require treatment)
vs. Loffler’s syndrome = transient pulmonary eosinophilia from parasitic infection
What is lupus pernio?
Lupus pernio- hyperpigmentation on central face, typically on nose, characteristic of sarcoidosis
Describe probable UIP pattern on HRCT
Probable UIP = peripheral and basilar predominant fibrosis but no honeycombing
-sometimes seen as early UIP (so honeycombing just not there yet)
What is Loffler syndrome?
Transient, self-limiting pulmonary eosinophilia with fleeting/migratory infiltrates and peripheral eosinophilia
Acute onset cough, dyspnea, wheeze, occasionally fever
Mechanism thought to be an allergic response to helminth (ascaris, strongy, and hookworms)
Typical antibody panel for drug-induced lupus
Positive ANA
Anti-histone Ab
(anti-dsDNA more in idiopathic SLE)
Drugs most likely to cause drug-induced lupus
Hydralazine, procainamide, INH
How long after getting drug is immune-checkpoint inhibitor induced pneumonitis most likely?
1-3 months, median 3 months
(basically not right after infusion)
Hepatopulmonary syndrome
(a) Aa gradient cutoff
(b) Describe the two mechanisms of anatomic shunt
(c) When supplemental O2 works less
HPS
(a) Aa gradient over 15
(b) Dilated capillary beds (so not all blood gets oxygenated) and new capillaries that bypass alveoli completely
(c) As the shunt fraction worsens, supplemental O2 correcs less
What group of PH does portopulmonary HTN fall into?
Group I
Which cirrhotic would you transplant- portopulmonary hypertension or hepatopulmonary syndrome?
HPS is an indication for transplant- PaO2 under 60 counts as a MELD exception
While portopulmonary HTN Is a contraindication to transplant, and may not improve with transplant
Name autoantibodies expected in each CTDs
(a) MCTD
(b) Sjogrens
(c) SLE
(d) RA
(e) Systemic sclerosis
(f) Anti-synthetase syndrome
CTD autoantibodies
(a) MCTD: anti-RNP
(b) Sjogrens: anti-SSA/SSB (Ro/La)
(c) SLE: anti-dsDNA
(d) RA: Anti-CCP and RF
(e) Systemic sclerosis/scleroderma: anti-SCl-70 (DNA topoisomerase)
(f) Anti-Jo1
For which CTD is annual PH screening recommended?
Annual screening with TTE for systemic sclerosis/scleroderma (anti-SCl-70 at highest risk) patients
PAH develops in over 15% of SS patients due to elevated endothin-1 => vasconstriction, vascular endothelial cell proliferation, smooth muscle hypertrophy
LAM
(a) Brief pathophysiology
(b) Immunohistochemical stain
(c) Imaging findings
(d) Effusions
LAM
(a) proliferation of muscles in bronchovascular bundle forming thin-walled homogenous cysts
(b) HMB-45 (muscle marker)
(c) Imaging: homogeneous thin-walled cysts
(d) Recurrent chylous effusions (from lymph accumulation)
LAM treatment
LAM treatment
-avoid estrogen containing compounds
-sirolimus = mTOR inhibitor to reduce smooth muscle proliferation
-pleurodesis given high risk (50-80%) of recurrent PTX
How can a male have LAM?
Tuberous sclerosis related, secondary LAM
Otherwise primary is all pre-menopausal F thought to be estrogen mediated
Name 4 ILDs most commonly associated with smoking
- RB-ILD
- DIP
- PLCH
- Acute eosinophilic PNA
Which cells/stains are pathognomonic for
(a) PLCH on BAL?
(b) LAM
(c) Amyloidosis
(a) Langerhan cells that stain +CD1a and S-100
(b) Muscle markers (actin, desmin); HMB-45
(c) Apple-green birefrigence with congo red staining on polarized microscopy
Found in acute or chronic eosinophilic PNA
(a) Pleural effusions
(b) Elevated serum IgE and eos
(c) Radiographic negative of pulmonary edema
(d) Interstitial fibrosis on TBBx
Eosinophilic PNA
(a) effusions in acute, not chronic
(b) Elevated serum IgE and peripheral eosinophilia more common in chronic
(c) Chronic- peripheral predominance = negative of pulmonary edema
(d) Fibrotic changes = chronic
What exposure to screen for that can identically mimic sarcoidosis
Berylliosis- from aerospace exposure, circuit boards/electronics, cuaseing cell mediated immune response in the lungs causing noncaseating granulomas
Lofgrens syndrome triad
Lofgrens- clinical triad of sarcoidosis with high rate of remission
-erythema nodosum
-bilateral hilar lymphadenopathy
-arthralgia (most commonly bilateral large joints like ankles)
BAL findings consistent with sarcoidosis
Sarcoidosis
-lymphocytic predominant BAL (over 20%)
-CD4/CD8 elevated (normal 1.5-2.0, sarcoid over 3.5)
Classic sarcoidosis imaging findings
Nodules along bronchovascular bundle/peri-bronchovascular (and fissure)
Typical first line treatment algorithm for sarcoidosis
Sarcoidosis treatment- start with steroids
Typically high-dose steroids 4-6 week burst followed by 6 month maintenance
Start MTX as steroid-sparing agent
Differentiate congenital and acquired pulmonary alveolar proteinosis
PAP
Congenital- due to congenital mutation in surfactant or GM-CSF receptor
Acquired (more common) due to autoantibody against GM-CSF
PAP
(a) Serum lab tests
(b) Expected PFT findings
(c) 2 classic chest imaging findings
PAP
(a) Elevated serum LDH and surfactant (not necessary but supportive)
(b) As with any alveolar filling process expect restriction and reduced diffusion
(c) Imaging findings
-bat wing appearance on CXR b/c of perihilar predominance of consolidations
-crazy paving due to alveolar filling and septal thickening with preserved architecture
PAP pathology
(a) BAL appearance
(b) Electron microscopy
(c) Stain
PAP pathology
(a) BAL- milky effluent, proteinaceous, acellular
(b) Electron microscopy with diagnostic lamellar bodies = laminated phospholipid structure
(c) PAS stain +
Treatment for PAP
PAP treatment
First line- whole lung lavage, typically require mor ethan one, average duration of repsonse about 15 months
Then inhaled or subQ GM-CSF proven to improve lung function in acquired PAP
Key opportunistic infections seen in PAP
PAP- increased risk for opportunistic infection, mnemonic ‘MAN’
Non-tuberculosis mycobacteria
Aspergillus
Nocardia
Pulmonary amyloidosis
(a) Mechanism of injury
(b) Possible supporting serum lab test
Pulmonary amyloid
(a) Deposition of insoluble proteins (beta-pleated sheet formation) in airways and parenchyma
(b) SPEP or UPEP with monclonal spike consistent with gammaopathy
Pulmonary amyloidosis
(a) Most characteristic imaging findings
(b) Role of laser therapy
Pulmonary amyloidosis
(a) Can be very variable but most classic are diffuse nodules that can cavitate and calcify
(b) Laser therapy for airway involvement (ex: tracheobronchial stenosis)
Birt-Hogg-Dube
(a) Mechanism/gene
(b) Clinical triad
Birt-Hogg-Dube
(a) Autosomal dominant mutation in folliculin gene
(b) Clinically:
-lung disease: cysts and high rate PTX
-fibrofolliculomas = dome shaped papules on face, upper extremities, trunk
-malignant renal tumors = renal cell carcinoma, clear cell, high lifetime risk so screening recommended
Mgmt of Birt-Hogg-Dube
-usual care for PTX
-routine screening for renal malignancy given high lifetime risk
Give ddx for noninfectious cystic lung disease
Birt-Hogg-Dube
LAM
PLCH (langerhan cell histiocytosis)
LIP (lymphocytic interstitial PNA)
Amyloidosis