{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:03:12Z","timestamp":1760238192484,"version":"build-2065373602"},"reference-count":40,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,6,27]],"date-time":"2022-06-27T00:00:00Z","timestamp":1656288000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diseases"],"abstract":"<jats:p>Hypersensitivity pneumonitis (HP) is a consequence of immune-mediated reactions caused by recurrent exposure to environmental agents. Recently, clinical practice guidelines for the diagnosis of HP were published and increased interest in HP. On the other hand, novel therapies have recently emerged for various diseases, and the management of drug-related pneumonitis (DRP) has become increasingly important. Among DRP, the HP pattern (DRP-HP) shows small, poorly defined centrilobular nodules with or without widespread areas of ground-glass opacity or lobular areas of decreased attenuation and vascularity. A similar radiological pattern of non-fibrotic HP can be induced, irrespective of inhalation (non-fibrotic HP) or intravenous administration (DRP-HP). However, their difference has not been well described, although the distribution of lesions in the lungs was slightly different between these two conditions. In this review, we focus on serum biomarkers of lung epithelial cells in order to investigate the difference between DRP-HP and non-fibrotic HP (common-HP). Serum levels of Krebs von den Lungen 6 (KL-6) might be relatively lower (occasionally normal) in DRP-HP than in common-HP, implying a mechanistic difference. KL-6 could be useful in discriminating between DRP and non-fibrotic HP (common type).<\/jats:p>","DOI":"10.3390\/diseases10030036","type":"journal-article","created":{"date-parts":[[2022,6,27]],"date-time":"2022-06-27T22:31:14Z","timestamp":1656369074000},"page":"36","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Serum Biomarkers in a Radiological Pattern of Non-Fibrotic Hypersensitivity Pneumonitis: Implications for Mechanistic Difference and Differential Diagnosis"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0740-4836","authenticated-orcid":false,"given":"Takayuki","family":"Takimoto","sequence":"first","affiliation":[{"name":"Department of Internal Medicine, National Hospital Organization Kinki-Chuo Chest Medical Center, 1180 Nagasone-Cho, Kita-Ku, Sakai City 591-8555, Osaka, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1463-3832","authenticated-orcid":false,"given":"Yukihiro","family":"Nakamura","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, National Hospital Organization Kinki-Chuo Chest Medical Center, 1180 Nagasone-Cho, Kita-Ku, Sakai City 591-8555, Osaka, Japan"},{"name":"Department of Cardiology, Pulmonology, Hypertension, and Nephrology, Ehime University Graduate School of Medicine, Toon 791-0295, Ehime, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"680","DOI":"10.1164\/rccm.201611-2201PP","article-title":"Hypersensitivity Pneumonitis: Perspectives in Diagnosis and Management","volume":"196","author":"Vasakova","year":"2017","journal-title":"Am. J. Respir. Crit. Care Med."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e36","DOI":"10.1164\/rccm.202005-2032ST","article-title":"Diagnosis of Hypersensitivity Pneumonitis in Adults. An Official ATS\/JRS\/ALAT Clinical Practice Guideline","volume":"202","author":"Raghu","year":"2020","journal-title":"Am. J. Respir. Crit. Care Med."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"e97","DOI":"10.1016\/j.chest.2021.03.066","article-title":"Diagnosis and Evaluation of Hypersensitivity Pneumonitis: CHEST Guideline and Expert Panel Report","volume":"160","author":"Travis","year":"2021","journal-title":"Chest"},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Skeoch, S., Weatherley, N., Swift, A.J., Oldroyd, A., Johns, C., Hayton, C., Giollo, A., Wild, J.M., Waterton, J.C., and Buch, M. (2018). Drug-Induced Interstitial Lung Disease: A Systematic Review. J. Clin. Med., 7.","DOI":"10.1183\/13993003.congress-2018.PA2244"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"260","DOI":"10.1016\/j.resinv.2013.09.001","article-title":"Consensus statement for the diagnosis and treatment of drug-induced lung injuries","volume":"51","author":"Kubo","year":"2013","journal-title":"Respir. Investig."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"4805","DOI":"10.1158\/1078-0432.CCR-20-0454","article-title":"Radiological Patterns of Drug-induced Interstitial Lung Disease (DILD) in Early-phase Oncology Clinical Trials","volume":"26","author":"Terbuch","year":"2020","journal-title":"Clin. Cancer Res."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1107","DOI":"10.1016\/j.chest.2020.11.027","article-title":"Chest CT Diagnosis and Clinical Management of Drug-Related Pneumonitis in Patients Receiving Molecular Targeting Agents and Immune Checkpoint Inhibitors: A Position Paper From the Fleischner Society","volume":"159","author":"Johkoh","year":"2021","journal-title":"Chest"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"892","DOI":"10.1016\/j.rmed.2008.01.005","article-title":"High-resolution computed tomography patterns and immunopathogenetic findings in drug-induced pneumonitis","volume":"102","author":"Takatani","year":"2008","journal-title":"Respir. Med."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Fujimoto, D., Kato, R., Morimoto, T., Shimizu, R., Sato, Y., Kogo, M., Ito, J., Teraoka, S., Nagata, K., and Nakagawa, A. (2016). Characteristics and Prognostic Impact of Pneumonitis during Systemic Anti-Cancer Therapy in Patients with Advanced Non-Small-Cell Lung Cancer. PLoS ONE, 11.","DOI":"10.1371\/journal.pone.0168465"},{"key":"ref_10","first-page":"101498","article-title":"Drug-related pneumonitis with radiographic hypersensitivity pneumonitis pattern: Three case series","volume":"34","author":"Nakamura","year":"2021","journal-title":"Respir Med. Case Rep."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"154","DOI":"10.1183\/16000617.0012-2019","article-title":"Management of pulmonary toxicity associated with immune checkpoint inhibitors","volume":"28","author":"Delaunay","year":"2019","journal-title":"Eur. Respir. Rev."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"6051","DOI":"10.1158\/1078-0432.CCR-16-1320","article-title":"PD-1 Inhibitor-Related Pneumonitis in Advanced Cancer Patients: Radiographic Patterns and Clinical Course","volume":"22","author":"Nishino","year":"2016","journal-title":"Clin. Cancer Res."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1485","DOI":"10.1164\/rccm.202005-2104LE","article-title":"Micronodular Pattern of Organizing Pneumonia or Hypersensitivity Pneumonia Induced by an Immune Checkpoint Inhibitor?","volume":"202","author":"Takimoto","year":"2020","journal-title":"Am. J. Respir. Crit. Care Med."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"872","DOI":"10.1136\/thorax.58.10.872","article-title":"Circulating KL-6 levels in patients with drug induced pneumonitis","volume":"58","author":"Ohnishi","year":"2003","journal-title":"Thorax"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"852","DOI":"10.1148\/radiol.2243011236","article-title":"Drug-induced pneumonitis: Thin-section CT findings in 60 patients","volume":"224","author":"Akira","year":"2002","journal-title":"Radiology"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"63","DOI":"10.2174\/1874306401206010063","article-title":"Drug induced interstitial lung disease","volume":"6","author":"Schwaiblmair","year":"2012","journal-title":"Open Respir. Med. J."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"373","DOI":"10.1034\/j.1399-3003.2000.15b25.x","article-title":"Methotrexate pneumonitis: Review of the literature and histopathological findings in nine patients","volume":"15","author":"Imokawa","year":"2000","journal-title":"Eur. Respir. J."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"607","DOI":"10.1016\/j.humpath.2014.12.017","article-title":"Granulomas and giant cells in hypersensitivity pneumonitis","volume":"46","author":"Castonguay","year":"2015","journal-title":"Hum. Pathol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"68","DOI":"10.1378\/chest.96.1.68","article-title":"New serum indicator of interstitial pneumonitis activity. Sialylated carbohydrate antigen KL-6","volume":"96","author":"Kohno","year":"1989","journal-title":"Chest"},{"key":"ref_20","first-page":"L193","article-title":"Pulmonary surfactant protein A-mediated uptake of phosphatidylcholine by alveolar type II cells","volume":"265","author":"Tsuzuki","year":"1993","journal-title":"Am. J. Physiol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"258","DOI":"10.1164\/ajrccm.162.1.9903014","article-title":"Serum levels of surfactant proteins A and D are useful biomarkers for interstitial lung disease in patients with progressive systemic sclerosis","volume":"162","author":"Takahashi","year":"2000","journal-title":"Am. J. Respir. Crit. Care Med."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1860","DOI":"10.1164\/ajrccm.152.6.8520747","article-title":"Pulmonary surfactant protein D in sera and bronchoalveolar lavage fluids","volume":"152","author":"Honda","year":"1995","journal-title":"Am. J. Respir. Crit. Care Med."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"723","DOI":"10.1164\/ajrccm\/147.3.723","article-title":"Elevated levels of lung surfactant protein A in sera from patients with idiopathic pulmonary fibrosis and pulmonary alveolar proteinosis","volume":"147","author":"Kuroki","year":"1993","journal-title":"Am. Rev. Respir. Dis."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1557","DOI":"10.1378\/chest.08-2209","article-title":"Serum surfactant protein-A is a strong predictor of early mortality in idiopathic pulmonary fibrosis","volume":"135","author":"Kinder","year":"2009","journal-title":"Chest"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"378","DOI":"10.1164\/ajrccm.165.3.2107134","article-title":"Comparative study of KL-6, surfactant protein-A, surfactant protein-D, and monocyte chemoattractant protein-1 as serum markers for interstitial lung diseases","volume":"165","author":"Ohnishi","year":"2002","journal-title":"Am. J. Respir. Crit. Care Med."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1680","DOI":"10.1164\/ajrccm.158.5.9803115","article-title":"Circulating KL-6 predicts the outcome of rapidly progressive idiopathic pulmonary fibrosis","volume":"158","author":"Yokoyama","year":"1998","journal-title":"Am. J. Respir. Crit. Care Med."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"164","DOI":"10.1111\/j.1440-1843.2006.00834.x","article-title":"Prognostic value of circulating KL-6 in idiopathic pulmonary fibrosis","volume":"11","author":"Yokoyama","year":"2006","journal-title":"Respirology"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Ohnishi, H., Miyamoto, S., Kawase, S., Kubota, T., and Yokoyama, A. (2014). Seasonal variation of serum KL-6 concentrations is greater in patients with hypersensitivity pneumonitis. BMC Pulm. Med., 14.","DOI":"10.1186\/1471-2466-14-129"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"163","DOI":"10.1007\/s00795-007-0360-0","article-title":"Immunohistochemical distribution of SP-D, compared with that of SP-A and KL-6, in interstitial pneumonias","volume":"40","author":"Ohtsuki","year":"2007","journal-title":"Med. Mol. Morphol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1186\/s41479-021-00087-6","article-title":"Surfactant protein D: A useful marker for differentiation of drug-induced pneumonia and bacterial pneumonia","volume":"13","author":"Waseda","year":"2021","journal-title":"Pneumonia (Nathan)"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"120","DOI":"10.5858\/arpa.2017-0138-SA","article-title":"Hypersensitivity Pneumonitis A Perspective From Members of the Pulmonary Pathology Society","volume":"142","author":"Miller","year":"2018","journal-title":"Arch. Pathol. Lab. Med."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"637","DOI":"10.1164\/ajrccm\/148.3.637","article-title":"KL-6, a mucin-like glycoprotein, in bronchoalveolar lavage fluid from patients with interstitial lung disease","volume":"148","author":"Kohno","year":"1993","journal-title":"Am. Rev. Respir. Dis."},{"key":"ref_33","first-page":"763","article-title":"Evaluation of serum KL-6 levels in summer-type hypersensitivity pneumonitis","volume":"36","author":"Nakajima","year":"1998","journal-title":"Nihon Kokyuki Gakkai Zasshi"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1576","DOI":"10.1016\/j.rmed.2015.10.005","article-title":"The usefulness of KL-6 and SP-D for the diagnosis and management of chronic hypersensitivity pneumonitis","volume":"109","author":"Okamoto","year":"2015","journal-title":"Respir. Med."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1186\/1465-9921-14-133","article-title":"Serum heat shock protein 47 levels in patients with drug-induced lung disease","volume":"14","author":"Kakugawa","year":"2013","journal-title":"Respir. Res."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1602419","DOI":"10.1183\/13993003.02419-2016","article-title":"Prevalence and incidence of interstitial lung diseases in a multi-ethnic county of Greater Paris","volume":"50","author":"Duchemann","year":"2017","journal-title":"Eur. Respir. J."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"97","DOI":"10.1186\/1465-9921-12-97","article-title":"Change in serum KL-6 level from baseline is useful for predicting life-threatening EGFR-TKIs induced interstitial lung disease","volume":"12","author":"Kawase","year":"2011","journal-title":"Respir. Res."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"217","DOI":"10.1111\/j.1440-1843.2006.00835.x","article-title":"Gefitinib-induced interstitial lung disease showing improvement after cessation: Disassociation of serum markers","volume":"11","author":"Kitajima","year":"2006","journal-title":"Respirology"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"1294","DOI":"10.1164\/ajrccm.158.4.9712003","article-title":"Serum and bronchoalveolar fluid KL-6 levels in patients with pulmonary alveolar proteinosis","volume":"158","author":"Takahashi","year":"1998","journal-title":"Am. J. Respir. Crit. Care Med."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1164\/ajrccm.156.1.9612043","article-title":"Pulmonary epithelial cell injury and alveolar-capillary permeability in berylliosis","volume":"156","author":"Inoue","year":"1997","journal-title":"Am. J. Respir. Crit. Care Med."}],"container-title":["Diseases"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2079-9721\/10\/3\/36\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T23:38:55Z","timestamp":1760139535000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2079-9721\/10\/3\/36"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,6,27]]},"references-count":40,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2022,9]]}},"alternative-id":["diseases10030036"],"URL":"https:\/\/doi.org\/10.3390\/diseases10030036","relation":{},"ISSN":["2079-9721"],"issn-type":[{"type":"electronic","value":"2079-9721"}],"subject":[],"published":{"date-parts":[[2022,6,27]]}}}