Diagnostic criteria for idiopathic pulmonary fibrosis – Authors’ reply

TY - JOUR

T1 - Diagnostic criteria for idiopathic pulmonary fibrosis – Authors’ reply

AU - Lynch, David A.

AU - Sverzellati, Nicola

AU - Travis, William D.

AU - Colby, Thomas V.

AU - Inoue, Yoshikazu

AU - Nicholson, Andrew G.

AU - Raoof, Suhail

AU - Richeldi, Luca

AU - Ryerson, Christopher J.

AU - Ryu, Jay H.

N1 - Funding Information: David A Lynch a lynchd@njhealth.org Nicola Sverzellati b William D Travis c Thomas V Colby d Yoshikazu Inoue f Andrew G Nicholson e Suhail Raoof g Luca Richeldi h Christopher J Ryerson i Jay H Ryu j a Department of Radiology, National Jewish Health, Denver, 80206 CO, USA Department of Radiology National Jewish Health Denver CO 80206 USA b Department of Medicine and Surgery, University of Parma, Parma, Italy Department of Medicine and Surgery University of Parma Parma Italy c Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, USA Department of Pathology Memorial Sloan Kettering Cancer Center New York NY USA d Department of Pathology, Mayo Clinic Scottsdale, Scottsdale, AZ, USA Department of Pathology Mayo Clinic Scottsdale Scottsdale AZ USA e Department of Histopathology, Royal Brompton and Hospital NHS Foundation Trust and National Heart and Lung Institute, Imperial College, London, UK Department of Histopathology Royal Brompton and Hospital NHS Foundation Trust and National Heart and Lung Institute Imperial College London UK f Clinical Research Center, National Hospital Organization Kinki-Chuo Chest Medical Center, Osaka, Japan Clinical Research Center National Hospital Organization Kinki-Chuo Chest Medical Center Osaka Japan g Division of Pulmonary Medicine, Lenox Hill Hospital, New York, NY, USA Division of Pulmonary Medicine Lenox Hill Hospital New York NY USA h Unità Operativa Complessa di Pneumologia, Agostino Gemelli University Hospital of the Catholic University of the Sacred Heart, Rome, Italy Unità Operativa Complessa di Pneumologia Agostino Gemelli University Hospital of the Catholic University of the Sacred Heart Rome Italy i Department of Medicine, University of British Columbia and St Paul's Hospital, Vancouver, BC, Canada Department of Medicine University of British Columbia St Paul's Hospital Vancouver BC Canada j Division of Pulmonary and Critical Care Medicine, Mayo Clinic Rochester, Rochester, MN, USA Division of Pulmonary and Critical Care Medicine Mayo Clinic Rochester Rochester MN USA We thank Marcel Koenigkam Santos and colleagues for their thoughtful comments on our Review. 1 We agree that interstitial lung disease (ILD) with airway-centered fibrosis represents a major diagnostic challenge, and that patients with this pattern often have hypersensitivity pneumonitis, 2 gastro-oesophageal reflux, aspiration, or connective tissue disease. 3 Given these multiple associations, the prevalence of idiopathic airway-centered fibrosis 4 remains unclear. The ATS/ERS classification paper in 2013 recognised bronchiolocentric patterns of interstitial pneumonia as a rare histological finding, but it was not clear whether this finding could be idiopathic. 5 Previous descriptions of the CT findings in this entity have been quite variable, including subpleural consolidation, 6 subpleural interstitial abnormality, 7 peribronchovascular ground glass abnormality, 3 and peribronchovascular interstitial thickening and traction bronchiectasis. 8 Because the CT findings are relatively non-specific, most of these cases would currently be included in the category of CT pattern indeterminate for UIP. The lack of a consistent, clear histological definition of airway-centered fibrosis has hampered understanding of this entity. Therefore, we agree with the authors’ suggestion that a systematic review of this topic is appropriate. With regard to the images presented in our online repository of high-resolution CT scans showing features of UIP , we hope to implement some of the suggestions of Santos and colleagues as we continue to update these cases. We also appreciate the comments of Lee Fidler and Shane Shapera. The reason for including the category of CT pattern indeterminate for UIP as a separate entity is because we believe that the probability of histological usual interstitial pneumonia (UIP) in this group is substantially higher than in patients with CT features most consistent with a non-IPF diagnosis. Although the paper 9 by Chung and colleagues did not support this contention, the population in this retrospective study might have been biased by the inclusion of patients enrolled in clinical IPF trials and the requirement for all patients to have had a surgical lung biopsy. Additional studies with broader populations are needed to confirm the prevalence of an IPF clinical diagnosis for patients in the indeterminate imaging category and the consistent with non-IPF diagnosis imaging category. We defined the category CT pattern indeterminate for UIP as having evidence of fibrosis with some inconspicuous features suggestive of non-UIP pattern. In most instances, these cases demonstrate some combination of ground glass opacity, lobular mosaic perfusion, and lobular air trapping, associated with evidence of fibrosis. We agree with Fidler and Shapera that use of this definition is challenging given the absence of clear and reproducible descriptions of what features qualify as inconspicuous. We hope that the publication of these guidelines and use of the online image repository will provide an impetus to study the specificity of CT features that suggest a non-IPF alternative diagnosis, thus providing a sharper delineation between the recommended diagnostic categories. Competing interests are the same as in the original Review.

PY - 2018/2

Y1 - 2018/2

UR - http://www.scopus.com/inward/record.url?scp=85041236290&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85041236290&partnerID=8YFLogxK

U2 - 10.1016/S2213-2600(18)30021-3

DO - 10.1016/S2213-2600(18)30021-3

M3 - Letter

C2 - 29413090

AN - SCOPUS:85041236290

SN - 2213-2600

VL - 6

SP - 138

EP - 153

JO - The Lancet Respiratory Medicine

JF - The Lancet Respiratory Medicine

IS - 2

ER -