Transcript Document
Refractory and Difficult to Control Asthma
Abubakr A Bajwa MD FCCP
Objectives
• To define difficult to control asthma and refractory asthma
• Understand factors related to refractory asthma
• Understand different options for management
Idiopathic Interstitial Pneumonias(IIPs)
Diffuse Parenchymal Lung Diseases
(DPLDs)
Abubakr A Bajwa MD
Pulmonary , Critical Care and Sleep
Medicine
CASE
Mild DOE - slowly progressing over past year
Nonproductive cough
Chest x-ray…
Restrictive PFTs
Dry crackles on chest exam
The DPLDs
BIP
GIP
BOOP
COP
NSIP
RB-ILD
Pulmonary
Fibrosis
UIP
LIP
ILD
AIP
DIP
DAD
HX,EG,PLCH
IPF
BO OB
Asbestosis
HP
EP
CVD
Radiation
Metals
Silicosis
etc.
Diagnoses of ILD
Others = sarcoid,
malignancies, LAM,
HX, EP
AIP/DAD
BOOP
LIP
CVD
NSIP “CFA”/IPF/UIP
Extrinsic = radiation,
drugs, hard metals,
occupational
CHP
Others
RBILD/DIP
Extrinsic
Diagnoses of ILD
– The Goal
AIP/DAD
BOOP
LIP
CVD
NSIP
“CFA”/IPF/UIP
CHP
Extrinsic
Others
RBILD/DIP
Bjoraker et al. (AJRCCM 1998)
Diagnoses (102)
0.14
0.08
0.04
0.04
0.17
0.62
0.02
0.01
0.01
0.02
0.03
UIP
NSIP
DIP
Bronchiolitis
BOOP
RB-ILD
CEP
HP
AIP
Other
ATS/ERS International Multidisciplinary Consensus Classification of the IIP
Diffuse Parenchymal Lung Disease
Idiopathic Interstitial
Pneumonias
Idiopathic Pulmonary
Fibrosis
Known cause
or associations
Granulomatous
Others: LAM, HX, EP
Others than IPF
DIP
RB-ILD
AIP
COP
NSIP
LIP
AJRCCM 2002
Major idiopathic interstitial pneumonias
Idiopathic pulmonary fibrosis
Idiopathic nonspecific interstitial pneumonia
Respiratory bronchiolitis–interstitial lung disease
Desquamative interstitial pneumonia
Cryptogenic organizing pneumonia
Acute interstitial pneumonia
Rare idiopathic interstitial pneumonias
Idiopathic lymphoid interstitial pneumonia
Idiopathic pleuroparenchymal fibroelastosis
Unclassifiable idiopathic interstitial pneumonias*
Potential Causes of ILD
Inhaled Agents
Inorganic: Silica, Asbestos, Beryllium
Organic: (HP), Animals, Birds, Farm antigens
Antibiotics, Antiarrhythmics, Anti-inflammatories,
Chemotherapeutics, Antidepressants, Radiation,
Oxygen
Sarcoidosis, PCLH/EG/HX, BOOP, LAM, UIP, NSIP,
DIP, RB-ILD, AIP, CEP
Malignant
Scleroderma, PM/DM, SLE, RA, MCTD, Ankylosing
spondylitis, Sjögren's, Behçet's
Atypical pneumonias, PCP, TB, CVID
Idiopathic
Connective Tissue Disease
Infectious
Drug-Induced
Lymphangitic carcinomatosis, BAC
Others
MPA, IPH
Adapted from: Flaherty, PCCU Vol 18, Lesson 3
(Chestnet.org)
IPF
Definition of IPF
Major Criteria
Exclusion of other known causes of ILD, such as certain drug toxicities, environmental exposures, and
connective tissue diseases
Abnormal pulmonary function studies that include evidence of restriction (reduced VC often with an
increased FEV1/FVC ratio) and impaired gas exchange [increased AaPO2 with rest or exercise or
decreased DLCO]
Bibasilar reticular abnormalities with minimal ground glass opacities on HRCT scans
Transbronchial lung biopsy or bronchoalveolar lavage (BAL) showing no features to support an
alternative diagnosis
Minor Criteria
Age > 50 yr
Insidious onset of otherwise unexplained dyspnea on exertion
Duration of illness > 3 mo
Bibasilar, inspiratory crackles (dry or "Velcro" type in quality)
IPF Survival
Bjoraker et al. (AJRCCM 1998)
History and Physical
Exposures
Drugs
Birds, farmer, etc.
Radiation
Hx of malignancy
Rheumatologic symptoms
Constitutional features
GERD
Recurrent infections
Family history
Velcro crackles
Clubbing
Desaturation ?
RHF or PAH ?
Old films
“ATS International Multidisciplinary Consensus Classification of the IIP” (AJRCCM
2002)
Typical Clinical Features
Clubbing
(25-50%), Velcro crackles, insidious onset of dyspnea, dry cough,
progressive course
Atypical Clinical Features
Young
age (<50), absence of restriction, inconclusive exposure history,
absence of dyspnea, lymphocytosis on BAL, significant constitutional
symptoms
At risk Occupations for IPF
Multicenter, case-control study
farming:
OR 1.6
livestock:
OR 2.7
hairdressing:
OR 4.4
metal dust work: OR 2.0
raising birds:
OR 4.7
stone cutting/polishing:
[1.0, 2.5]
[1.3, 5.5]
[1.2, 16.3]
[1.0, 4.0]
[1.6, 14.1]
OR 3.9 [1.2, 12.7]
vegetable dust/animal dust exposure:
OR, 4.7 [2.1, 10.4]
Baumgartner (A J Epid 2000)
Diagnosis- PFT
Restrictive
Reduced
TLC, VC, FVC
Increased FEV1/FVC ratio
Reduced diffusing capacity
Desaturation with exertion
Prognosis…
UIP/IPF
CT Images
CT Images
Images from ATS Statement 2002
Attempted therapies
Interferon gamma - negative
Acetylcysteine – some positive effects
ERAs – Bosentan negative, ambrisentan on
going
Steroids - negative
Steroids plus Imuran - negative
Steroids plus Imuran plus Acetylcysteine –
on going
Zileuton – animal studies
Sildenafil – QOL improved but negative
Anticoagulation with warfarin
Pirfenidone – promising
Nintedanib - promising
NSIP
Can’t know NSIP without knowing UIP
NSIP
Histopathologically does not meet any of the other IIP’s
Mimic IPF
Ill-defined from clinical standpoint
Frequently NSIP-like areas seen in IPF
Prevalent ground glass attenuation
HRCT is neither sensitive or specific for NSIP
Better prognosis, better response to Tx
Consider
CVD/CTD, Drugs, Infection, immune-deficiency (HIV), Hypersensitivity Pneumonitis
Semantics…
By definition, there is a variable and no specific clinical profile of a patient
with NSIP.
Avoid giving patients diagnosis of NSIP as a clinical diagnosis, but consider
“IIP-NSIP pattern”.
Task One in NSIP : H&P
Look for related conditions to make a primary diagnosis
CTD/CVD (can present after ILD)
HP
Occupational exposures?, drugs?
Immunodeficiency / HIV
If none identified clinical diagnosis of idiopathic NSIP to account for the
NSIP “pattern”
Clinical features
Younger than patients with IPF
Gradual to subacute presentation
6 months – 3 years of symptoms to Dx
Dyspnea, cough, fatigue, weight loss
Onset around 40-50yo
Can occur in children
Clubbing less frequent than IPF (~10-35%)
Crackles, sometimes insp. Squeaks
Restrictive physiololgy
Desaturation with exercise
NSIP
NSIP
NSIP Images
Images from ATS Statement 2002
Treatment - NSIP
Favorable responsiveness to corticosteroids
Look for primary or alternative diagnoses that can have an NSIP
pattern
Hypersensitivity,
drugs, exposures, CVD
Prognosis
NSIP > UIP
5-year
survival of up to 70% for NSIP
Cellular NSIP > Fibrotic NSIP
10
year survival: 100% vs 35-90%
Prognosis
Bjoraker. AJRCCM 1998.
101 IIP:
22 Fibrotic vs 7 Cellular NSIP
Travis WD. AJSP 2000; 24(1):19-33.
COP
The great mimicker
COP
Formerly BOOP
“Organizing pneumonia” ≠ COP
Injury pattern seen in many conditions from drug reactions, infections, CVD, IBD, Inhalational injuries,
etc.
More acute to subacute presentation
More constitutional features
Restrictive PFTs
Patchy areas of consolidation & GGO, Subpleural, Lower zones, can present as nodule(s) or
masses
Histologic DDx:
DAD, NSIP, DIP, UIP
Responsive to steroids
COP
ATS Statement, AJRCCM 2002
AIP
Could be ALI/ARDS
AIP
Acute to fulminant presentation
Clinical
criteria for ARDS (idiopathic)
Patchy alveolar infiltrates and GGO diffuse consolidation
Histopath: Organizing DAD
No proven treatment
Including
corticosteroids
Mortality > 50%
Smoking related ILDs
RB --- RB-ILD --- DIP
RB --- RB-ILD --- DIP
RB is a histopathologic feature found in most smokers
RB-ILD
Intraluminal pigmented (golden brown) macrophages
Clinical features of ILD with RB findings
DIP
More advanced ILD with pigmented macrophages filling alveoli more diffusely in larger
segments of lung
RB-ILD
RB-ILD ---
Milder symptoms overlap with symptoms
attributable to emphysema
GGO, centrilobular nodules, thickened
bronchial/bronchiolar walls
Radiographic DDx: NSIP, DIP, HP
RB with bronchiolocentric distribution
More advanced features of ILD
Diffuse GGO
Lower zone, subpleural
More reticular lines and some honeycombing
Numerous macrophage accumulation more
diffusely
DIP
Lacks bronchiolocentric distribution of RB-ILD
With Tx, GGO resolves
DIP
LIP
LIP
Controversy as to whether it should be considered an IIP
Slow, insidious onset
Lymphoma (bronchial MALT) vs Reactive lymphoid hyperplasia
Some LIP were probably (now) cellular NSIP or lymphoma,...
Hypogammaglobulinemia; Polyclonal, or Monoclonal (75%) gammopathy
Consider autoimmune, CVD, infections:
SLE, RA, Sjogren’s, Chronic active hepatitis, Pernicious anemia, Hashimoto’s, immunodeficiency (HIV),
PBC, MG, AIHA, Castleman’s, PCP, HepB, EBV, drugs/inhalational
LIP
Mostly GGO >> perivascular cysts/HC, reticulation 50%, nodules/consolidation
Histopath:
Immunohistochemistry and gene-rearrangement studies
Tx with steroids typically
1/3 progresses to diffuse fibrosis
Dense interstitial lymphoid infiltrates with DDX of NSIP & HP; non-necrotrizing granulomas
Acute Fibrinous and Organizing Pneumonia
The dominant histologic pattern
is intraalveolar fibrin deposition
and associated organizing
pneumonia
Abubakr A Bajwa MD FCCP
Pulmonary Critical Care and Sleep Medicine
University of Florida College of Medicine/Jacksonville
CONDITIONS
PREVALENCE*
PAH
15 per million
IPAH
5.9 per million
FPAH†
28−100 U.S. families
APAH-scleroderma
Portopulmonary hypertension
HIV
Sickle cell disease
Schistosomiasis
8−26.7%
1−6%
0.5% estimate
32%
11.8−80%
* Prevalence varies substantially depending on the type, etiology, and underlying condition
† Reported estimates are based on personal communications
Note: Numbers may also reflect differences in diagnostic criteria (e.g., ECHO vs right heart catheterization) and
study design (e.g., retrospective vs prospective)
Cystic Fibrosis
Introduction
Autosomal recessive
Most fatal
1 in 2000 – 3000 live births
Genetics
Single large gene
mutation that
encodes CFTR
protein
Most common Δ
F508
Types of defects
Pathogenesis
Abnormal secretions
Defective Cl sceretion from epithelium
Increased Na absorption
Increased Cl secretion in sweat
Chronic infection
Chronic airway obstruction
Bacterial colonization
Nonmotile mucoid phenotype acquisistion
Altered rheology and bacterial killing
Psuedomonas infection
Radiological Appearence
Diagnosis
A sweat chloride value greater than 60 meq/L
Normal sweat chloride concentration may be observed in approximately 1 percent
of patients with CF
Diagnosis
Molecular diagnosis
Nasal potential difference measurements: Abnormalities in epithelial chloride secretion nasal
transepithelial potential difference in the basal state, after nasal perfusion with amiloride, and
after nasal perfusion with a chloride-free solution
Newborn screening — Most infants with CF have elevated blood levels of immunoreactive
trypsin (IRT),
Management
Usually in hospital:
IV antibiotics
Nutrition
Physiotherapy
Rest
Home management:
More cost effective
Tailored
Ensure all components of in hospital care can be provided
Alpha one anti-trypsin deficiency
History
1963 by Laurel and Eriksson
Missing band for 1 antotrypsin
Epidemiology
Common and under-recognized
3.1 million americans - emphysema
In COPD population 1.9% had deficiency
So about 59,000 - 66,000 have symptomatic COPD due to deficiency
3.4 million worldwide with zz, sz, ss phenotypet
Fewer than 10,000 are receiving specific therapy
Survey shows that there is a mean delay of about 7.2 yrs bw
symtoms and diagnosis
Genetics
Autosomal co-dominant
> 100 alleles
SERPINA1 gene ch 14
MM homozygous for normal M allele
ZZ homozygous for Z allele - severe deficiency
Normal concentration 80-220 mg/dl
Pathophysiology
Serine protease inhibitors (serpin)
Major role in inactivating neutrophil elastatses
Retention of polymerized aggregates in hepatocytes - liver disease
Loss of natural antiprotease screen - emphysema
Mechanism of Emphysema
Polymerisation and retention of polymers in liver cells
Decrease amount available in lung
Proteolytic activity by neutrophil elastase unchecked
Smoking - increases elastases
Z- phenotype functionally less active
Z-type antitrypsin polymers - chemoattractants for neutrophils
Anti-inflammatory Properties
Block human neutrophil peptides
Regulated pro-inflammatory cytokines such as TNF, IL8, IL1
Clinical Manifestations
Lung disease:
Emphysema
Early onset (4th-5th decade)
Mean FEV1 from NHLBI registry was 43% (mean age 46)
Panacinar
Disproportionate disease in lung bases(15% may have normal chest
xrays, 36% may have apical emphysema on CT chest)
Clinical Manifestations
Lung Disease:
Bronchiectasis:
Originally Larsson 1978 showed 11.3% of ZZ had bronchiectasis
From NHLBI only 2%
Recommendation: unknown bronchiectasis - check levels
As levels fall below 11mol/L or about 80mg/dl.
Role of CPET
Cardiopulmonary exercise testing
• Cardiopulmonary exercise testing (CPET), also known as cardiopulmonary exercise stress testing, is a
non-invasive tool that provides a comprehensive evaluation of exercise responses involving
the cardiovascular, pulmonary, hematopoietic, neuropsychological, and musculoskeletal systems.
Role of CPET
•
Cardiopulmonary exercise testing entails measurements of:
–
–
–
–
•
Oxygen uptake (VO2)
Carbon dioxide output (VCO2)
Minute ventilation (VE)
12-lead electrocardiography (ECG), blood pressure (BP) monitoring and pulse oximetry.
These data are gathered during a maximal symptom-limited incremental exercise test. In certain circumstances,
an additional measurement of arterial blood gases may be used to assess pulmonary gas exchange.
Indication
Recommendation
grade
Detection of exercise-induced bronchoconstriction
A
Detection of exercise-induced arterial oxygen desaturation
B
Functional evaluation of subjects with unexplained exertional dyspnea and/or exercise intolerance and
normal resting lung and heart function
D
To recognize specific disease exercise response patterns that may help in the differential diagnosis of
ventilatory versus circulatory causes of exercise limitation
C
Functional and prognostic evaluation of patients with COPD
B, C
Functional and prognostic evaluation of patients with ILD
B, B
Functional and prognostic evaluation of patients with CF
C, C
Functional and prognostic evaluation of patients with PPH
B, B
Functional and prognostic evaluation of patients with CHF
B, B
Evaluation of interventions (Maximal incremental test)
C
Evaluation of interventions (High-intensity constant work-rate ‘‘endurance’’ tests)
B
Prescription of exercise training
B