{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T23:08:08Z","timestamp":1774566488296,"version":"3.50.1"},"reference-count":17,"publisher":"BMJ","issue":"2","license":[{"start":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T00:00:00Z","timestamp":1772064000000},"content-version":"unspecified","delay-in-days":25,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2026,2,6]]},"published-print":{"date-parts":[[2026,2]]},"abstract":"<jats:p>Anaphylaxis, the most severe form of an allergic reaction, is a potentially life-threatening systemic reaction requiring prompt and effective management. A subset of cases shows a recurrence of symptoms despite adequate care and full clinical response. These biphasic or even multiphasic courses provide a unique challenge for clinicians, especially as reported incidence varies, risk factors are unclear and clear management strategies are lacking in current guidelines. This is especially true for multiphasic anaphylaxis presenting with multiple relapses into anaphylaxis despite adequate response to standard treatment with epinephrine. Due to the relatively rare occurrence of multiphasic anaphylaxis, case reports providing examples of clinical management can provide an important source of insight into this clinical problem.<\/jats:p>\n                  <jats:p>In this study, we present the case of a woman in her 60s presenting with multiphasic anaphylaxis to clarithromycin, with subsequent analysis showing a high likelihood of systemic mastocytosis, though she did not meet formal diagnostic criteria.<\/jats:p>","DOI":"10.1136\/bcr-2025-270996","type":"journal-article","created":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T14:00:16Z","timestamp":1772114416000},"page":"e270996","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":1,"title":["Multiphasic anaphylaxis in the emergency and intensive care setting"],"prefix":"10.1136","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-4610-1173","authenticated-orcid":false,"given":"Margret Ann","family":"Schneider","sequence":"first","affiliation":[{"name":"Intensive Care, Reinier de Graaf Gasthuis, Delft, Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hans","family":"de Groot","sequence":"additional","affiliation":[{"name":"Allergology, Reinier de Graaf Gasthuis, Delft, Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jan-Willem","family":"Geerts","sequence":"additional","affiliation":[{"name":"Intensive Care, Reinier de Graaf Gasthuis, Delft, Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"239","published-online":{"date-parts":[[2026,2,26]]},"reference":[{"key":"2026022606001345000_19.2.e270996.1","unstructured":"Borgdorff H , Bosch A , Bouma M , et al . NHG-behandelrichtlijn. geneesmiddelen en zuurstof in spoedeisende situaties. Nederlands Huisartsen Genootschap. 2025 Available: https:\/\/richtlijnen.nhg.org\/behandelrichtlijnen\/geneesmiddelen-en-zuurstof-spoedeisende-situaties"},{"key":"2026022606001345000_19.2.e270996.2","doi-asserted-by":"crossref","DOI":"10.1016\/j.waojou.2020.100472","article-title":"World allergy organization anaphylaxis guidance 2020","volume":"13","author":"Cardona","year":"2020","journal-title":"World Allergy Organ J"},{"key":"2026022606001345000_19.2.e270996.3","unstructured":"Working Group of Resuscitation Council UK . Emergency treatment of anaphylaxis guidelines for healthcare providers. Working Group of Resuscitation Council UK; 2021. Available: https:\/\/www.resus.org.uk\/sites\/default\/files\/2021-05\/Emergency%20Treatment%20of%20Anaphylaxis%20May%202021_0.pdf"},{"key":"2026022606001345000_19.2.e270996.4","doi-asserted-by":"crossref","first-page":"3388","DOI":"10.1016\/j.jaip.2020.07.036","article-title":"Risk Factors and Characteristics of Biphasic Anaphylaxis","volume":"8","author":"Kraft","year":"2020","journal-title":"J Allergy Clin Immunol Pract"},{"key":"2026022606001345000_19.2.e270996.5","doi-asserted-by":"crossref","DOI":"10.1002\/ams2.599","article-title":"Association between biphasic reactions and the systems of symptoms and treatment in patients with anaphylaxis hospitalized from the emergency department","volume":"7","author":"Nomura","year":"2020","journal-title":"Acute Med Surg"},{"key":"2026022606001345000_19.2.e270996.6","doi-asserted-by":"crossref","first-page":"1089","DOI":"10.1016\/j.jaci.2020.08.015","article-title":"Persistent, refractory, and biphasic anaphylaxis: A multidisciplinary Delphi study","volume":"146","author":"Dribin","year":"2020","journal-title":"J Allergy Clin Immunol"},{"key":"2026022606001345000_19.2.e270996.7","doi-asserted-by":"crossref","first-page":"1480","DOI":"10.1016\/j.ajem.2018.05.009","article-title":"Biphasic anaphylaxis: A review of the literature and implications for emergency management","volume":"36","author":"Pourmand","year":"2018","journal-title":"Am J Emerg Med"},{"key":"2026022606001345000_19.2.e270996.8","doi-asserted-by":"crossref","first-page":"270","DOI":"10.1016\/j.ajem.2025.10.020","article-title":"Retrospective comparison between 0.3 mg and 0.5 mg dosing of intramuscular epinephrine for anaphylaxis","volume":"99","author":"Jackson","year":"2026","journal-title":"Am J Emerg Med"},{"key":"2026022606001345000_19.2.e270996.9","doi-asserted-by":"crossref","first-page":"312","DOI":"10.1016\/j.anai.2015.07.015","article-title":"Biphasic reactions in patients with anaphylaxis treated with corticosteroids","volume":"115","author":"Ko","year":"2015","journal-title":"Annals of Allergy, Asthma & Immunology"},{"key":"2026022606001345000_19.2.e270996.10","doi-asserted-by":"crossref","first-page":"939","DOI":"10.1159\/000524612","article-title":"Glucocorticoids and Rates of Biphasic Reactions in Patients with Adrenaline-Treated Anaphylaxis: A Propensity Score Matching Analysis","volume":"183","author":"Nagata","year":"2022","journal-title":"Int Arch Allergy Immunol"},{"key":"2026022606001345000_19.2.e270996.11","doi-asserted-by":"crossref","first-page":"2239","DOI":"10.1016\/j.jaip.2019.07.005","article-title":"Anaphylaxis Management: Time to Re-Evaluate the Role of Corticosteroids","volume":"7","author":"Campbell","year":"2019","journal-title":"J Allergy Clin Immunol Pract"},{"key":"2026022606001345000_19.2.e270996.12","doi-asserted-by":"crossref","first-page":"196","DOI":"10.23822\/EurAnnACI.1764-1489.15","article-title":"Corticosteroids in management of anaphylaxis; a systematic review of evidence","volume":"49","author":"Liyanage","year":"2017","journal-title":"Eur Ann Allergy Clin Immunol"},{"key":"2026022606001345000_19.2.e270996.13","first-page":"1194","article-title":"Do Corticosteroids Prevent Biphasic Anaphylaxis?","volume":"5","author":"Alqurashi","year":"2017","journal-title":"The Journal of Allergy and Clinical Immunology: In Practice"},{"key":"2026022606001345000_19.2.e270996.14","doi-asserted-by":"crossref","first-page":"2232","DOI":"10.1016\/j.jaip.2019.04.018","article-title":"Evaluation of Prehospital Management in a Canadian Emergency Department Anaphylaxis Cohort","volume":"7","author":"Gabrielli","year":"2019","journal-title":"J Allergy Clin Immunol Pract"},{"key":"2026022606001345000_19.2.e270996.15","doi-asserted-by":"crossref","DOI":"10.3390\/diagnostics13213307","article-title":"A Puzzling Mast Cell Trilogy: Anaphylaxis, MCAS, and Mastocytosis","volume":"13","author":"G\u00fclen","year":"2023","journal-title":"Diagnostics (Basel)"},{"key":"2026022606001345000_19.2.e270996.16","doi-asserted-by":"crossref","DOI":"10.3390\/cancers15235626","article-title":"Review and Updates on Systemic Mastocytosis and Related Entities","volume":"15","author":"Li","year":"2023","journal-title":"Cancers (Basel)"},{"key":"2026022606001345000_19.2.e270996.17","doi-asserted-by":"crossref","DOI":"10.3389\/falgy.2022.934436","article-title":"Multi-phasic life-threatening anaphylaxis refractory to epinephrine managed by extracorporeal membrane oxygenation (ECMO): A case report","volume":"3","author":"Grafeneder","year":"2022","journal-title":"Front Allergy"}],"container-title":["BMJ Case Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bcr-2025-270996","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T14:00:19Z","timestamp":1772114419000},"score":1,"resource":{"primary":{"URL":"https:\/\/casereports.bmj.com\/lookup\/doi\/10.1136\/bcr-2025-270996"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,2]]},"references-count":17,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,2,26]]},"published-print":{"date-parts":[[2026,2]]}},"alternative-id":["10.1136\/bcr-2025-270996"],"URL":"https:\/\/doi.org\/10.1136\/bcr-2025-270996","relation":{},"ISSN":["1757-790X"],"issn-type":[{"value":"1757-790X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,2]]}}}