An Official American Thoracic Society/European Respiratory Society Statement: Update of the International Multidisciplinary Classification of the Idiopathic Interstitial Pneumonias

Overview

Journal Am J Respir Crit Care Med

Specialty Critical Care

Date 2013 Sep 17

PMID 24032382

Citations 1587

Authors

William D Travis

Ulrich Costabel

David M Hansell

Talmadge E King Jr

David A Lynch

Andrew G Nicholson

Christopher J Ryerson

Jay H Ryu

Moises Selman

Athol U Wells

Jurgen Behr

Demosthenes Bouros

Kevin K Brown

Thomas V Colby

Harold R Collard

Carlos Robalo Cordeiro

Vincent Cottin

Bruno Crestani

Marjolein Drent

Rosalind F Dudden

Jim Egan

Kevin Flaherty

Cory Hogaboam

Yoshikazu Inoue

Takeshi Johkoh

Dong Soon Kim

Masanori Kitaichi

James Loyd

Fernando J Martinez

Jeffrey Myers

Shandra Protzko

Ganesh Raghu

Luca Richeldi

Nicola Sverzellati

Jeffrey Swigris

Dominique Valeyre

Affiliations

Soon will be listed here.

Abstract

Background: In 2002 the American Thoracic Society/European Respiratory Society (ATS/ERS) classification of idiopathic interstitial pneumonias (IIPs) defined seven specific entities, and provided standardized terminology and diagnostic criteria. In addition, the historical "gold standard" of histologic diagnosis was replaced by a multidisciplinary approach. Since 2002 many publications have provided new information about IIPs.

Purpose: The objective of this statement is to update the 2002 ATS/ERS classification of IIPs.

Methods: An international multidisciplinary panel was formed and developed key questions that were addressed through a review of the literature published between 2000 and 2011.

Results: Substantial progress has been made in IIPs since the previous classification. Nonspecific interstitial pneumonia is now better defined. Respiratory bronchiolitis-interstitial lung disease is now commonly diagnosed without surgical biopsy. The clinical course of idiopathic pulmonary fibrosis and nonspecific interstitial pneumonia is recognized to be heterogeneous. Acute exacerbation of IIPs is now well defined. A substantial percentage of patients with IIP are difficult to classify, often due to mixed patterns of lung injury. A classification based on observed disease behavior is proposed for patients who are difficult to classify or for entities with heterogeneity in clinical course. A group of rare entities, including pleuroparenchymal fibroelastosis and rare histologic patterns, is introduced. The rapidly evolving field of molecular markers is reviewed with the intent of promoting additional investigations that may help in determining diagnosis, and potentially prognosis and treatment.

Conclusions: This update is a supplement to the previous 2002 IIP classification document. It outlines advances in the past decade and potential areas for future investigation.

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