Ross Miller, Timothy Craig Allen, Roberto J. Barrios, Mary Beth Beasley, Louise Burke, Philip T. Cagle, Vera Luiza Capelozzi, Yimin Ge, Lida P. Hariri, Keith M. Kerr, Andras Khoor, Brandon T. Larsen, Eugene J. Mark, Osamu Matsubara, Mitra Mehrad, Mari Mino-Kenudson, Kirtee Raparia, Anja Christiane Roden, Prudence Russell, Frank Schneider, Lynette M. Sholl, and Maxwell Lawrence Smith (2017) Hypersensitivity Pneumonitis: A Perspective From Members of the Pulmonary Pathology Society. Archives of Pathology & Laboratory Medicine In-Press.

Early Online Release

Hypersensitivity Pneumonitis: A Perspective From Members of the Pulmonary Pathology Society

Ross Miller, MD; Timothy Craig Allen, MD, JD; Roberto J. Barrios, MD; Mary Beth Beasley, MD; Louise Burke, MD; Philip T. Cagle, MD; Vera Luiza Capelozzi, MD, PhD; Yimin Ge, MD; Lida P. Hariri, MD, PhD; Keith M. Kerr, BSc, MBChB, FRCPath, FRCPE; Andras Khoor, MD; Brandon T. Larsen, MD, PhD; Eugene J. Mark, MD; Osamu Matsubara, MD, PhD; Mitra Mehrad, MD; Mari Mino-Kenudson, MD; Kirtee Raparia, MD; Anja Christiane Roden, MD; Prudence Russell, MBBS (Hons), FRCPA; Frank Schneider, MD; Lynette M. Sholl, MD; Maxwell Lawrence Smith, MD

From the Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, Texas (Drs Miller, Barrios, Cagle, and Ge); the Department of Pathology, University of Texas Medical Branch, Galveston (Dr Allen); the Department of Pathology, Mount Sinai Medical Center, New York, New York (Dr Beasley); the Department of Histopathology, Cork University Hospital, Cork, Ireland (Dr Burke); the Department of Pathology, University of São Paulo, São Paulo, Brazil (Dr Capelozzi); the Department of Pathology, Massachusetts General Hospital, Boston (Drs Hariri, Mark, and Mino-Kenudson); the Department of Pathology, Aberdeen University School of Medicine, Aberdeen, United Kingdom (Dr Kerr); the Department of Laboratory Medicine and Pathology, Mayo Clinic, Jacksonville, Florida (Dr Khoor); the Department of Laboratory Medicine and Pathology, Mayo Clinic, Scottsdale, Arizona (Drs Larsen and Smith); the Department of Pathology, National Defense Medical College, Tokorozawa, Japan (Dr Matsubara); the Department of Pathology, Vanderbilt University Medical Center, Nashville, Tennessee (Dr Mehrad); the Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois (Dr Raparia); the Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota (Dr Roden); the Department of Pathology, St Vincent's Pathology, Fitzroy, Australia (Dr Russell); the Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania (Dr Schneider); and the Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts (Dr Sholl).

Reprints: Timothy Craig Allen, MD, JD, Department of Pathology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555 (email: tcallen@utmb.edu).

Context.— Hypersensitivity pneumonitis (HP) is a lung disease that develops in susceptible individuals after inhalational exposure to an organic antigen or chemical compound. Pathogenesis is attributed to a combination of type III (immune complex–mediated) and type IV (delayed) hypersensitivity reactions to the inciting agent.

Objective.— To provide an overview of the current status of the medical literature regarding hypersensitivity pneumonitis.

Data Sources.— A literature search was performed using PubMed and Google search engines. The terms “hypersensitivity pneumonitis” and “extrinsic allergic alveolitis” were used, with the search starting on January 9, 2017, and concluding March 8, 2017.

Conclusions.— As a pathologist, it is important to consider hypersensitivity pneumonitis when examining lung specimens because it is often clinically and pathologically overlooked. Recognizing the often subtle findings and correlating them with the patient's history or suggesting a thorough clinical investigation of potential exposures can be of help in identifying the underlying condition so that the patient can be appropriately managed.