{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,23]],"date-time":"2026-08-23T18:16:51Z","timestamp":1787509011417,"version":"build-2736575974"},"reference-count":26,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,3,7]],"date-time":"2026-03-07T00:00:00Z","timestamp":1772841600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T00:00:00Z","timestamp":1776297600000},"content-version":"vor","delay-in-days":40,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Sci Rep"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Kounis syndrome is an acute coronary syndrome (ACS) triggered by allergic reactions via mast cell activation, classically accompanied by anaphylaxis. However, ACS associated with mild or subclinical allergic reactions may be underrecognized. We investigated immune markers and autonomic nervous system activity in patients with ACS and characterized allergy-associated ACS without anaphylactic symptoms. Among 375 patients treated for ACS (April 2022 to March 2024), 49 were prospectively enrolled. Patients were classified into non-allergy-associated ACS (ACS-NA, n\u2009=\u200932) and allergy-associated ACS (ACS-AL, n\u2009=\u200917) groups. ACS-AL was subdivided into the non-anaphylactic (ACS-AL(nonA), n\u2009=\u200911) and anaphylactic (ACS-AL(withA), n\u2009=\u20096) groups. Allergic status was comprehensively assessed. Serum IgE and plasma histamine were measured at ACS onset. Heart rate variability (HRV) parameters were analyzed using 24-h ambulatory monitoring within 1\u00a0week after percutaneous coronary intervention. The ACS-AL(nonA) and ACS-AL(withA) groups showed significantly higher IgE and histamine levels than the ACS-NA group (P\u2009&lt;\u20090.05), with overlapping distributions. HRV analysis revealed elevated LF\/HF ratios and reduced daytime HF in both groups, indicating sympathetic predominance. ACS-AL, even without anaphylaxis, involves immune activation and autonomic imbalance. Combined assessment of IgE, histamine, and HRV may improve the identification of this phenotype.<\/jats:p>","DOI":"10.1038\/s41598-026-38633-1","type":"journal-article","created":{"date-parts":[[2026,3,7]],"date-time":"2026-03-07T07:17:33Z","timestamp":1772867853000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Allergy-associated acute coronary syndrome without anaphylaxis in a prospective observational study"],"prefix":"10.1038","volume":"16","author":[{"given":"Mari","family":"Amino","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shie","family":"Takizawa","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seiji","family":"Morita","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kanae","family":"Kitatani","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ayumi","family":"Sasaki","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Atsuhiko","family":"Yagishita","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoshihide","family":"Nakagawa","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuji","family":"Ikari","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Koichiro","family":"Yoshioka","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,3,7]]},"reference":[{"key":"38633_CR1","doi-asserted-by":"publisher","first-page":"21","DOI":"10.1186\/1939-4551-6-21","volume":"6","author":"SL Prescott","year":"2013","unstructured":"Prescott, S. L. et al. A global survey of changing patterns of food allergy burden in children. World Allergy Organ. J. 6, 21 (2013).","journal-title":"World Allergy Organ. J."},{"key":"38633_CR2","volume-title":"Immunobiology: The Immune System in Health and Disease","author":"CA Janeway Jr","year":"2001","unstructured":"Janeway, C. A. Jr. et al. Immunobiology: The Immune System in Health and Disease 5th edn. (Garland Science, 2001).","edition":"5"},{"key":"38633_CR3","doi-asserted-by":"publisher","first-page":"456","DOI":"10.3109\/07853890.2014.927714","volume":"46","author":"G Lippi","year":"2014","unstructured":"Lippi, G., Cervellin, G. & Sanchis-Gomar, F. Immunoglobulin E (IgE) and ischemic heart disease: which came first, the chicken or the egg?. Ann. Med. 46, 456\u2013463 (2014).","journal-title":"Ann. Med."},{"key":"38633_CR4","doi-asserted-by":"publisher","first-page":"471","DOI":"10.1016\/j.jaci.2023.09.038","volume":"153","author":"C Keet","year":"2024","unstructured":"Keet, C. et al. IgE to common food allergens is associated with cardiovascular mortality in the National Health and Nutrition Examination Survey and the Multi-Ethnic Study of Atherosclerosis. J. Allergy Clin. Immunol. 153, 471-478.e3 (2024).","journal-title":"J. Allergy Clin. Immunol."},{"key":"38633_CR5","doi-asserted-by":"publisher","first-page":"734","DOI":"10.3390\/ph16050734","volume":"16","author":"J Neumann","year":"2023","unstructured":"Neumann, J. et al. Function and role of histamine H1 receptor in the mammalian heart. Pharmaceuticals (Basel) 16, 734 (2023).","journal-title":"Pharmaceuticals (Basel)"},{"key":"38633_CR6","doi-asserted-by":"publisher","first-page":"37","DOI":"10.1007\/978-1-4614-7261-2_3","volume-title":"Drug Allergy","author":"BA Baldo","year":"2013","unstructured":"Baldo, B. A. & Pham, N. H. Mechanisms of hypersensitivity. In Drug Allergy 37\u201390 (Springer, 2013)."},{"key":"38633_CR7","doi-asserted-by":"publisher","first-page":"121","DOI":"10.1111\/j.1742-1241.1991.tb10251.x","volume":"45","author":"NG Kounis","year":"1991","unstructured":"Kounis, N. G. & Zavras, G. M. Histamine-induced coronary artery spasm: the concept of allergic angina. Br. J. Clin. Pract. 45, 121\u2013128 (1991).","journal-title":"Br. J. Clin. Pract."},{"key":"38633_CR8","doi-asserted-by":"publisher","first-page":"1545","DOI":"10.1515\/cclm-2016-0010","volume":"54","author":"NG Kounis","year":"2016","unstructured":"Kounis, N. G. Kounis syndrome: an update on epidemiology, pathogenesis, diagnosis and therapeutic management. Clin. Chem. Lab. Med. 54, 1545\u20131559 (2016).","journal-title":"Clin. Chem. Lab. Med."},{"key":"38633_CR9","doi-asserted-by":"publisher","first-page":"121","DOI":"10.1007\/978-1-4939-1568-2_8","volume":"1220","author":"JS Janicki","year":"2015","unstructured":"Janicki, J. S., Brower, G. L. & Levick, S. P. 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The authors take full responsibility for the content, interpretation, and conclusions presented, and no AI tools were used for data analysis or generation of scientific content.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"AI Use"}}],"article-number":"12491"}}