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  • Macrophages, fibroblasts, myofibroblasts, collagen-related molecules, noncollagenous proteins (fibronectin, laminin)
  • Over 100 distinct types of interstitial lung diseases With all of these, it is no wonder that classifying them has been difficult
  • First thing you want to do is determine which of 4 major categories the ILD falls into
  • Lumpers (clinicians) and splitters (pathologists) Most of the ILD’s result in fibrosis – in the past many ILD’s were called IPF Histologic PATTERN
  • HPS = an autosomal recessive disorder characterized by oculocutaneous albinism and platelet abnormalities, is a rare cause of UIP The finding of even rare poorly formed granulomas or giant cells in the interstitium should raise suspicion for chronic hypersensitivity pneumonia
  • 2 fibroblastic foci adjacent to dense fibrosis Arrows – dense subpleural fibrosis with collapse of alveoli Dense scarring by areas of normal lung – characteristic of IPF Note no necrosis or substantial inflammation
  • This was the definition in 2000. There is now diagnostic criteria without having to do a biopsy.
  • This is double previous estimates Prevalence = 80,000 Incidence = 30,000
  • Increasing prev/inc with increasing age More common in men than women Rarely seen before the age of 40
  • Tachypnea d/t increased WOB Schamroth's window test
  • Bilateral reticular infiltrates, subpleural and lower lobe predominance
  • A – normal B – loss of lung volume and bibasilar reticular opacities C – severe loss of lung volume D – honeycombing and PH
  • Decreased dlco may actually precede loss of lung volume (d/t less pulmonary capillary volume and VQ mismatch)
  • Resting hypoxemia is due to VQ mismatching With exercise, A-a gradient widens and the PaO2 falls
  • Diagnosis relies on grading lesions that vary in both age and location
  • Number of deaths related to IPF are 14 times more than asbestosis Some remain stable for long periods of time while others experience acute exacerbations and death
  • IPF study group
  • IPF study group
  • Suggests a genetic component – molecular studies are underway worldwide to find the genetic marker
  • Same type of process that takes place when skin is damaged
  • In a person with genetic predisposition repeated non-specific insults to the epithelium and parenchyma occur. Initiation of fibrotic response (fibrotic foci) may involve Th1 or Th2
  • TGF-B and CTGF are normally associated with wound healing and expressed at these sites
  • INSPIRE (international study of survival outcomes in IPF)

Idiopathic Pulmonary Fibrosis.ppt Idiopathic Pulmonary Fibrosis.ppt Presentation Transcript

  • Idiopathic Pulmonary Fibrosis Brian D. Southern Senior Talk August 2008
  • OBJECTIVES
    • Know the definitions of ILD, IIP, and IPF
    • Understand the pathogenesis of IPF
    • Appreciate the clinical features
    • Realize how the diagnosis of IPF is made
    • Know current therapies
    • Become aware of areas of current research and novel therapeutic approaches
    • Be able to summarize current thinking about IPF
  • Interstitial Lung Disease (ILD) or Diffuse Parenchymal Lung Disease (DPLD) Mason: Murray & Nadel's Textbook of Respiratory Medicine, 4th ed.
    • Any process that results in inflammatory-fibrotic infiltration of the alveolar septa resulting in effects on the capillary endothelium and alveolar epithelium.
    • “ Death occurred about three months and a half after the onset of the acute disease and the lung was two thirds of the normal size, grayish in color, and hard as cartilage. Microscopically these areas showed advanced fibrotic changes and great thickening of the alveolar walls.”
    • - Sir William Osler, 1892
    • Generic term used to describe many conditions that cause breathlessness and/or cough and are associated with radiographic bilateral lung abnormalities.
  • INTERSTIAL LUNG DISEASES Connective Tissue Diseases Scleroderma Polymyositis-Dermatomyositis Systemic Lupus Erythematosus Rheumatoid Arthritis Mixed Connective Tissue Disease Ankylosing Spondyitis Treatment-Related / Drug-Induced Antibiotics – nitrofurantoin, sulfasalazine Antiarrhythmics – amiodarone, propanolol Anti-inflammatories – gold, penacillamine Anti-convulsants – dilantin Chemotherapeutic agents – bleomycin, cyclophosphamide, methotrexate, azathioprine Therapeutic radiation Oxygen toxicity Narcotics Primary (Unclassified) Sarcoidosis Langerhans cell histiocytosis Amyloidosis Pulmonary vasculitis Lipoid pneumonia Lymphangitic carcinomatosis Bronchoalveolar carcinoma Pulmonary lymphoma Gaucher’s Disease Niemann-Pick Disease Hermansky-Pudlak syndrome Neurofibromatosis Lymphangioleiomyomatosis Tuberous Sclerosis ARDS AIDS Bone Marrow Transplantation Postinfectious Eosinophilic pneumonia Alveolar Proteinosis Diffuse Alveolar Hemorrhage Syndromes Alveolar microlithiasis Metastatic calcification Occupational and Environmental Diseases Inorganic Organic Silicosis Bird breeder’s lung Asbestosis Farmer’s lung Hard-metal pneumoconiosis Bacteria – e.g. NTB mycobacteria Coal worker’s pneumoconiosis Fungi – e.g. Aspergillus Berylliosis Animal protein – e.g. Avian Aluminum oxide fibrosis Chemical sensitizers - Talc pneumoconiosis e.g. isocyanates Siderosis (arc welder) Stannosis (tin) Idiopathic Fibrotic Disorders Acute interstitial pneumonitis (Hamman-Rich syndrome) Idiopathic Pulmonary Fibrosis Familial Idiopathic Pulmonary Fibrosis Desquamative intersitial pneumonitis Respiratory bronchiolitis Cryptogenic organizing pneumonia Nonspecific interstitial pneumonitis Lymphocytic interstitial pneumonia (Sjögrens Syndrome, AIDS, Hashimoto’s) Autoimmune pulmonary fibrosis (inflammatory bowel disease, PBC, ITP, AIHA)
  • ATS/ERS International Multidisciplinary Consensus Classification of the Idiopathic Interstitial Pneumonias, Am J Respir Crit Care Med . 2002
  • QUICK HISTORY OF IIP
    • In 1969, Liebow and Carrington described 5 types of chronic interstitial pneumonias based on histology:
    • Usual interstitial pneumonia (UIP)
    • Bronchiolitis obliterans interstitial pneumonia and diffuse alveolar damage (BIP)
    • Desquamative interstitial pneumonia (DIP)
    • Lymphocytic interstitial pneumonia (LIP)
    • Giant cell interstitial pneumonia (GIP)
    • In 2002, the ATS/ERS published their consensus classification of IIP based on Clinical-Radiologic-Pathologic categories:
    Clinical-Radiologic-Pathologic Diagnosis Histologic Pattern Idiopathic Pulmonary Fibrosis (Cryptogenic fibrosing alveolitis) Usual interstitial pneumonia Nonspecifiic interstitial pneumonia (provisional) Nonspecific interstitial pneumonia Cryptogenic organizing pneumonia Organizing pneumonia Acute interstitial pneumonia Diffuse alveolar damage Respiratory bronchiolitis ILD Respiratory bronchiolitis Desquamative interstitial pneumonia Desquamative interstitial pneumonia Lymphoid interstitial pneumonia Lymphoid interstitial pneumonia
  • ATS/ERS International Multidisciplinary Consensus Classification of the Idiopathic Interstitial Pneumonias, Am J Respir Crit Care Med .
  • USUAL INTERSTITIAL PNEUMONIA PATTERN
    • The UIP pattern can be seen in the following conditions:
      • IPF
      • Familial IPF
      • Collagen vascular diseases
      • Drug toxicity
      • Chronic hypersensitivity pneumonitis
      • Asbestosis
      • Hermansky-Pudlak syndrome
    The term UIP is usually reserved for patients in whom the lesion is idiopathic UIP ≈ IPF
  • Key histologic features:
    • Dense fibrosis with remodeling of lung architecture , frequent honeycomb fibrosis
    • Fibroblastic foci usually at the edge of scarring
    • Patchy lung involvement
    • Usually subpleural distribution
    Important negative findings:
    • No active lesions typical of other ILD’s
    • Lackof marked interstitial chronic inflammation
    • No (or rare) granulomas
    • No evidence of inorganic dust deposits (e.g. asbestos bodies)
    • Lack of marked eosinophilia
    USUAL INTERSTITIAL PNEUMONIA PATTERN
  • Mason: Murray & Nadel's Textbook of Respiratory Medicine, 4th ed. Idiopathic Pulmonary Fibrosis, Gross and Huninghake, NEJM, 2001. USUAL INTERSTITIAL PNEUMONIA PATTERN
  • HONEYCOMB PATTERN Pictures taken from http://mediswww.meds.cwru.edu/ecsample/yeartwo/pulmonary/interstitial.html
  • IDIOPATHIC PULMONARY FIBROSIS ATS definition: “IPF is a distinctive type of chronic fibrosing interstitial pneumonia of unknown cause limited to the lungs and associated with a surgical lung biopsy showing a histologic pattern of UIP.”
    • A distinct type of chronic fibrosing interstitial pneumonia
    • Unknown cause
    • Limited to the lungs
    • Associated with a histologic pattern of usual interstitial pneumonia (UIP)
  • EPIDEMIOLOGY Raghu et. al., Am J of Resp Crit Care Med 2006
    • Estimated to affect approx 5 million people worldwide
    • Most cases are sporadic, but rare cases of familial IPF have been described
    • The most common (and deadly) interstitial lung disease
  • EPIDEMIOLOGY Raghu et. al., Am J of Resp Crit Care Med 2006
  • CLINICAL PRESENTATION
    • Middle age 50-70s
    • New onset of progressive exertional dyspnea and non-productive cough
    • Most have symptoms for 12-18 months prior to definitive evaluation
    • Constitutional symptoms are uncommon
    • Weight loss, fever, fatigue, myalgias, or arthralgias occasionally present
    • Detailed occupational and exposure history
  • PHYSICAL EXAM
    • Bibasilar late inspiratory fine crackles (Velcro rales)
    • Clubbing – 40-75% - late in disease course
    • Cardiac exam usually normal until middle-late stages
    • - augmented P2, right-sided heave, S3 gallop
    • Cyanosis
    • Rash, arthritis, myositis should suggest an alternate diagnosis
    • Tachypnea
  • CXR Idiopathic Pulmonary Fibrosis, Gross and Hunninghake, NEJM, 2001. 16% of patients with ILD have normal chest x-rays Courtesy of W. Richard Webb, MD.
  • CXR
  • CXR Mason: Murray & Nadel's Textbook of Respiratory Medicine, 4th ed.
  • PFTs PFT’s Source: images.md Restrictive pattern Reduced TLC, VC, and/or RV ( decreased compliance ) Normal or increased FEV 1 /FVC Decreased D L CO =
  • ABG ABG = Hypoxemia, respiratory alkalosis Decreased PaO 2 with rest or exercise Increased A-a gradient Other lab tests that might be useful? Elevated ESR Hypergammaglobulinemia Low-titer positive ANA (21% patients with IPF) RF Circulating immune complexes Cryoimmunoglobulins
  • HIGH RES CT
    • Can now be used to differentiate IPF from other ILD
    • Can determine extent and severity of disease activity
    • Can be used to detect disease, especially in pts with no or minimal changes on CXR
    Idiopathic Pulmonary Fibrosis, Gross and Hunninghake, NEJM, 2001. Peripheral, subpleural fibrosis Alternating areas of normal tissue Honeycombing Traction bronchiectasis Later stages - more diffuse reticular pattern prominent in lower lung zones associated with thickened interlobular septa
  • BAL in IPF
    • Role and value of serial BAL in IPF previously unknown
    • Increased inflammatory cells in IPF, but no predominant type
    156 subjects with biopsy proven UIP/IPF enrolled between 1982-1996 BAL within 3 weeks of lung biopsy Linear relationship between increasing neutrophil percentage and the risk of mortality Each doubling in the neutrophil percentage was associated with a nearly 30% increased risk of death or transplantation in adjusted analysis ([HR] 1.28; 95% CI, 1.01 to 1.62; p = 0.04). There was no association with lymphocyte or eosinophil percentage. Suggests that BAL fluid neutrophil percentage at the time of diagnosis of IPF is an independent predictor of time to death.
    • Kinder et al, Chest , Jan 2008
  • LUNG BIOPSY
    • Gold Standard for diagnosis of IPF (and IIP’s)
    • Large piece of lung parenchyma is required, optimally from several sites
    • Transbronchial biopsy is only useful for ruling out other disorders
    • Can be performed by thoracotomy, thorascopy, or VATS
    OTHER STUDIES IN IPF
    • Gallium Scanning ( 67 Ga) used for staging “alveolitis” in ILD, e.g sarcoidosis
    • Not useful – difficult to interpret, very low specificity
    • VQ scan reveals patchy, non-segmental areas of decreased V
    • decreased perfusion in lower lung zones
    • increased perfusion of upper lung zones (due to PH)
  • ATS/ERS CRITERIA FOR DIAGNOSIS OF IPF IN ABSENCE OF SURGICAL LUNG BIOPSY Major Criteria : Exclusion of other known causes of ILD Abnormal PFTs that include evidence of restriction and impaired gas exchange Bibasilar reticular abnormalities with minimal ground glass opacities on HRCT Transbronchial lung biopsy or BAL showing no features to support alternative dx Minor Criteria : Age > 50 Insidious onset of otherwise unexplained dyspnea on exertion Duration of illness greater than 3 months Bibasilar inspiratory crackles (dry or “Velcro”-type in quality) ALL of the major criteria plus at least THREE minor criteria.
  •  
  • NATURAL HISTORY / PROGNOSIS
    • Worst prognosis of all the ILD’s
    • Disease course is variable
    • 5-year survival rate is 30-50%
    • 40% IPF patients die of respiratory failure
    • Others die of complicating illnesses, mainly CAD and infections
    • End-stage disease is characterized by severe PH with cor pulmonale that does not improve with oxygen
    • Incidence of bronchogenic carcinoma is increased in patients with IPF
    • Median survival after diagnosis is less than 3 years
    • Factors associated with shortened survival:
    • Increased neutrophil count
    • older age
    • poor pulmonary function at presentation
    • recent deterioration in results of PFT’s
    • advanced fibrosis
  • ACUTE EXACERBATIONS OF IPF
    • Several recent clinical trials have shown that multiple subclinical and
    • acute exacerbations lead to decline in pulmonary function
    • Traditional view: slow, steady decline in lung fuction  respiratory failure
    • Martinez et al, Ann Intern Medicine , 2005
    168 patients in the placebo group of a trial evaluating interferon-γ1b (mild-mod IPF) Measures of physiology and dyspnea assessed at 12-week intervals; hospitalizations; and the pace of deterioration and cause of death over a median period of 76 weeks. Minimal physiologic deterioration or worsening severity of dyspnea over time Frequent hospitalizations for respiratory disorders (23%, 21% died) IPF was the primary cause of death in 89% who died Acute clinical deterioration preceded death in 47%
    • Kim et al, Eur Resp J , 2006
    Analysis of 147 IPF patients demonstrated 2-year frequency of acute exacerbations was 9.6%
  • ACUTE EXACERBATIONS OF IPF Consensus group in 2007 defined acute exacerbation:
    • Diagnosis of IPF
    • Unexplained development of worsening of dyspnea within 30 days
    • HRCT with new ground-glass abnormalities
    • No evidence of pulmonary infection by ET aspirate or BAL
    • Exclusion of alternative causes, e.g. HF, PE
    Treatment:
    • Broad-spectrum antibiotics
    • High-dose steroids (prednisone 1 mg/kg)
  • GENETIC SUSCEPTIBILITY? Up to 3% of cases of IPF appear to cluster in families (Familial IPF) Armanios et al, NEJM 2007.
    • 73 probands from the Vanderbilt Familial Pulmonary Fibrosis Registry for mutations in hTERT and hTR (telomerase RT and telomerase RNA)
    • Demonstrated that mutation was inherited in autosomal dominant fashion with variable penetrance
    • Those with IPF had mutant telomerase and short telomeres
    • Telomeres shorten with each cell division and ultimately lead to apoptosis
    • Proposed that fibrosis occurs due to death of alveolar cells
  • ASSOCIATED RISK FACTORS
    • Up to 75% of index patients with IPF are current or former smokers
    • Latent viral infections have also been reported to have an association
    • Given the similarity between asbestosis and IPF, is there a causative environmental agent?
    • Chronic aspiration?
  • GERD AND IPF Raghu et al, Eur Resp J, Oct 2006.
    • 65 consecutive patients with IPF were subjected to 24-h pH monitoring and esophageal manometry
    • 133 patients with intractable asthma and GERD used for comparison
    • Prevalence of GERD in IPF patients was 87% but only 47% had symptoms
    • GERD was higher in IPF patients (76% versus 57%; p = 0.020)
    • Despite tx with standard dose PPI, 12/19 still had abnormal pH
    • Conclusion: GERD is highly prevalent and often clinically occult in patients with IPF, and often does not respond entirely to standard dose PPI
  • PATHOGENESIS Originally thought inflammation  fibrosis Animal models Early IPF is dominated by inflammatory cells Asymptomatic relatives of patients with familial IPF have evidence of alveolitis in the absence of disease PROBLEMS: 1) Little inflammation is seen histologically 2) Measurements of inflammation do not correlate 3) Anti-inflammatory therapies DO NOT WORK! Alveolar macrophage thought to play a major role Secretes proinflammatory and profibrotic cytokines Promote collagen deposition
  • PATHOGENESIS
    • Starting around 1998, studies began to demonstrate that inflammation is NOT a prominent finding in most cases of IPF/UIP.
    • These sites are typical in alveolar epithelial injury
    • Abnormal wound healing involving epithelial cells and fibroblasts
    • Activated epithelial cells release potent fibrogenic molecules and cytokines, such as TNF α and TGF β 1
  • PATHOGENESIS
  • PATHOGENESIS
  • TREATMENT ATS recommendation (2000): Prednisone + Azathioprine or Cyclophosphamide Consensus recommendation (2008): Prednisone + Azathioprine + N-acetylcysteine
  • STEROIDS Cochrane Systematic Review in 2003 Fifteen studies were selected as potentially eligible for meta-analysis. After further analysis of full text papers, no RCTs or CCTs were identified as suitable and therefore no data was available for inclusion in any meta-analysis. All studies were excluded due to inadequate methodologies.
    • Currently there is no evidence to support the routine use of corticosteroids alone in the management of IPF.
  • AZATHIOPRINE
    • Raghu et al, Am Rev Respir Dis 1991 .
      • 27 newly diagnosed patients with IPF
      • Prednisone + Azathioprine vs. Prednisone + Placebo, follow-up 9 years
      • After 1 year, P+A had better lung function, but was not significant
      • 43% (6/14) died vs. 77% (10/13)
    • Side effects: leukopenia,
    • GI-related
    Raghu G, et al. Am Rev Respir Dis. 1991;144:291-296. P = 0.02 (age adjusted) P = 0.16 Probability of Survival Years 1.0 0.8 0.6 0.4 0.2 0 0 1 2 3 4 5 6 7 8 9 Azathioprine + Prednisone (n = 14) Prednisone (n = 13)
  • CYCLOPHOSPHAMIDE
    • Collard et al, Chest, 2004
      • Retrospective study looking at 164 patients with IPF from 1984-2002
      • 82 patients on prednisone and oral cyclophosphamide vs. 82 patients on prednisone alone
      • No difference in survival from time of initial visit
    • Multiple other small studies have been unimpressive
    • Toxicity is major (pancytopenia, hemorrhagic cystitis, GI-related)
  • N-acetylcysteine (NAC)
    • Demedts et al, NEJM, 2005.
      • 182 patients with UIP
      • Prednisone + Azathioprine + High-dose NAC (600mg TID) vs. P/A
      • Significant difference in the deterioration of VC and D L CO at 12 months
        • Relative difference of 9% and 24% respectively
      • Oxidant-antioxidant imbalance?
    8/75 (11%) Pred+Aza+ Placebo 7/80 (9%) NAC+Pred+Aza Mortality, P = NS
  • LUNG TRANSPLANT
    • IPF is the most common ILD among referrals for transplant and the 2 nd most frequent disease for which lung transplantation is performed
    • Criteria: Evidence of UIP plus any of the following:
            • DLCO < 39% predicted
            • Decrement in FVC > 10% during 6 months
            • Decrease in pulse ox below 88% during 6-minute walk test
            • Honeycombing on HRCT
    • 5-year survival for lung transplant in IPF is 40-50%
    • SLT has been the standard treatment
    • Living donor lobar lung transplant (LDLLT) - Date et al, Chest 2005
    • 9 patients with IIP dependent on systemic steroids (up to 50mg/day)
    • Transplant of two lower lobes from two healthy relatives
    • After 10-48 months of follow-up 8/9 still alive (one died of acute rejection)
  • PERFENIDONE Mechanism of Action:
    • Included 267 patients in 73 different centers
    • Pirfenidone 1800 mg/day vs. 1200 mg/day vs. placebo
    • VC, SpO2 on exertion, number of acute exacerbations were primary endpoints
    • At week 52: Difference in VC between groups was 70mL and 80mL
          • No significant difference in lowest SaO2 on exertion
          • No significant difference in the number of acute exacerbations
          • Significant difference in progression-free survival
    Currently in Phase III trials in the U.S. (CAPACITY) Phase III trial in Japan ended last month:
    • inhibits TGF- β -stimulated collagen synthesis
    • decreases the extracellular matrix
    • blocks fibroblast proliferation in-vivo
    Adverse effects: rash, GI effects, fatigue
  • OTHER TREATMENT OPTIONS Limited data:
    • Methotrexate
    • Cyclosporine
    • Colchicine
    • Penicillamine
    Interferon gamma-1b:
    • important in “wound healing”
    • PCRT suggested a possible mortality benefit
    • Large multinational trial (INSPIRE) was stopped when the primary endpoint of mortality benefit was not achieved
    Drug Mechanism Status Bosentan (BUILD-1) Endothelin receptor agonist Phase III Etanercept TNF- α blocker Phase II Imatinib C-Abl and PDGF TK-inhibitor Phase II FG-3019 Anti-CTGF monoclonal Ab Phase II planned
  • SUMMARY
    • IPF is the most common ILD with the worst prognosis
    • The most important distinction is differentiate IPF from the other IIP’s
    • Biopsy is the gold standard for diagnosis, histology = UIP pattern with fibroblast foci (hallmark of IPF)
    • Most common presentation is 50-60 y.o. male with progressive dyspnea and non-productive cough
    • Most common physical exam findings are “Velcro” rales +/- clubbing
    • Most important diagnostic studies are CXR, PFT’s, ABG, and HRCT
    • Higher BAL neutrophil percentage at time of diagnosis = worse prognosis?
    • If certain clinical criteria are met, can diagnose IPF without biopsy
    • Acute exacerbations are now recognized to be an important target for therapy
  • SUMMARY
    • Possible genetic component involving mutant telomeres, resulting in apoptosis of alveolar cells
    • There is a high correlation with GERD in IPF
    • Newly accepted hypothesis that fibrosis is a result of aberrant “wound healing” resulting from repeated injury of unknown cause
    • There is still no effective therapy for IPF
    • Current recommendation is steroids + azathioprine + NAC
    • SLT improves 5-year survival, LDLLT shows promise in advanced disease
    • Perfenidone will likely be the next option in therapy for IPF
    • There are a number of novel therapies on the horizon
  • References Kinder BW et al. , Baseline BAL neutrophilia predicts early mortality in idiopathic pulmonary fibrosis. Chest . Vol 133(1): pp 226-32, Jan 2008. Martinez FJ et al. (IPF Study Group). The Clinical Course of Patients with Idiopathic Pulmonary Fibrosis. Ann Intern Med . Vol 142: pp 963-967, 2005. Kim DS et al . Acute exacerbation of idiopathic pulmonary fibrosis: frequency and clinical features. Eur Resp J . Vol 27: pp143-150, 2006. Selman et al. Idiopathic Pulmonary Fibrosis: Prevailing and Evolving Hypotheses about Its Pathogenesis and Implications for Therapy. Annals of Internal Medicine . Vol 134: 2, pp. 136-151, 2001. Raghu, G et al . Azathioprine combined with prednisone in the treatment of idiopathic pulmonary fibrosis: a prospective, double-blind randomized, placebo-controlled clinical trial. Am. Rev. Respir. Dis . 144: 291-296, 1991. Collard et al, Combined corticosteroid and cyclophosphamide therapy does not alter survival in idiopathic pulmonary fibrosis. Chest . 125(6):2169-74, 2004. Maurits Demedts et al , High-dose acetylcysteine in Idiopathic Pulmonary Fibrosis . NEJM , Vol 353: 2229-2242, 2005. Armanios MY et al. Telomerase mutations in families with idiopathic pulmonary fibrosis . NEJM 356: 1317-26, 2007. Mason: Murray & Nadel’s Textbook of Respiratory Medicine, 4 th ed. Chapter 53 – Approach to Diagnosis and Management of the Idiopathic Interstitial Pneumonias. King and Schwarz , 2005. American Thoracic Society/European Respiratory Society International Multidisciplinary Consensus Classification of the Idiopathic Interstitial Pneumonias . Am J Respir Crit Care Med . Vol 165, pp 277-304, 2002. Gross and Hunninghake , Idiopathic Pulmonary Fibrosis. NEJM . Vol 345, No 7: pp 517-525, 2001. Verma and Slutsky , Idiopathic Pulmonary Fibrosis – New Insights. NEJM . Vol 356, No 13: pp 1370-1372, 2007. Noth and Martinez. Recent Advances in Idiopathic Pulmonary Fibrosis . Chest 132: 637-50, 2007. Noble PW. Idiopathic Pulmonary Fibrosis: Natural History and Prognosis . Clin Chest Med 27, S11-16, 2006. American Thoracic Society, Idiopathic Pulmonary Fibrosis: Diagnosis and Treatment . Am. J. Respir. Crit. Care Med ., Volume 161, Number 2, 646- 664, 2000. Richeldi L, Davies HR, Ferrara G, Franco F . Corticosteroids for idiopathic pulmonary fibrosis . Cochrane Database of Systematic Reviews 2003, Iss 3. Raghu G et al . High prevalence of abnormal acid gastro-oesophageal reflux in idiopathic pulmonary fibrosis . Eur Respir J. Vol 28(4): 884-5, 2006. Orens et al . International Guidelines for the Selection of Lung Transplant Candidates: 2006 Update—A Consensus Report From the Pulmonary Scientific Council of the International Society for Heart and Lung Transplantation . The Journal of Heart and Lung Transplantation . Volume 25, Issue 7, Pages A1-A20, 745-868 (July 2006) Date et al . A New Treatment Strategy for Advanced Idiopathic Interstitial Pneumonia*: Living-Donor Lobar Lung Transplantation Chest , Sep 2005; 128: 1364 – 1370.