Hypersensitivity pneumonitis: Current concepts in pathogenesis, diagnosis, and treatment

Hayley Barnes, Lauren Troy, Cathryn T. Lee, Anne Sperling, Mary Strek, Ian Glaspole

Research output: Contribution to journalReview ArticleOtherpeer-review

17 Citations (Scopus)


Hypersensitivity pneumonitis is an immune-mediated interstitial lung disease caused by an aberrant response to an inhaled exposure, which results in mostly T cell–mediated inflammation, granuloma formation, and fibrosis in some cases. HP is diagnosed by exposure identification, HRCT findings of ground-glass opacities, centrilobular nodules, and mosaic attenuation, with traction bronchiectasis and honeycombing in fibrotic cases. Additional testing including serum IgG testing for the presence of antigen exposure, bronchoalveolar lavage lymphocytosis, and lung biopsy demonstrating granulomas, inflammation, and fibrosis, increases the diagnostic confidence. Treatment for HP includes avoidance of the implicated exposure, immunosuppression, and anti-fibrotic therapy in select cases. This narrative review presents the recent literature in the understanding of the immunopathological mechanisms, diagnosis, and treatment of HP.

Original languageEnglish
Pages (from-to)442-453
Number of pages12
Issue number2
Publication statusPublished - Feb 2022

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