{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T05:20:45Z","timestamp":1787721645412,"version":"build-2784847793"},"reference-count":8,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T00:00:00Z","timestamp":1787702400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:p>Hereditary angioedema with C1-inhibitor deficiency (HAE-C1INH) is a rare bradykinin-mediated disorder that may present predominantly with gastrointestinal symptoms, leading to diagnostic delay and unnecessary interventions. We report a 26-year-old man with recurrent abdominal pain, watery diarrhea, bowel wall edema, and transient ascites since 2022, repeatedly misdiagnosed as infectious gastroenteritis. He also reported recurrent hand and foot swelling. Complement testing showed low C4 and reduced C1-inhibitor function, and repeat testing confirmed low C1-inhibitor antigen and function, supporting type 1 HAE-C1INH. During follow-up, genetic testing identified a heterozygous likely pathogenic nonsense variant in SERPING1, NM_000062.3:c.1480C&amp;gt;T (p.Arg494Ter\/R494*). Family investigation of 50 relatives identified 13 clinically suspected affected individuals, including three who reportedly died from laryngeal edema; laboratory confirmation was available for the proband and two relatives. This case emphasizes that recurrent, self-limited abdominal attacks with transient ascites should prompt C4 and C1-inhibitor testing and family counseling.<\/jats:p>","DOI":"10.3389\/fimmu.2026.1828352","type":"journal-article","created":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T04:46:03Z","timestamp":1787719563000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Case Report: Hereditary angioedema masquerading as gastroenteritis"],"prefix":"10.3389","volume":"17","author":[{"given":"Xiaofeng","family":"Ren","sequence":"first","affiliation":[{"name":"Department of Gastroenterology, Sanmenxia Central Hospital","place":["Sanmenxia, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jialin","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Gastroenterology, Beijing Friendship Hospital, Capital Medical University","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yajun","family":"Xu","sequence":"additional","affiliation":[{"name":"Department of Radiology, Henan University of Science and Technology Affiliated Yellow River Hospital","place":["Sanmenxia, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,8,26]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1016\/j.waojou.2026.101335","article-title":"The 2025 WAO guidelines for the classification, diagnosis, and treatment of hereditary angioedema, with consideration of worldwide disparities","volume":"19","author":"V\u00e1zquez","year":"2026","journal-title":"World Allergy Organ J"},{"key":"B2","doi-asserted-by":"publisher","first-page":"24","DOI":"10.1007\/s12016-025-09027-4","article-title":"Hereditary angioedema with normal C1 inhibitor: an updated international consensus paper on diagnosis, pathophysiology, and treatment","volume":"68","author":"Zuraw","year":"2025","journal-title":"Clin Rev Allergy Immunol"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1111\/jth.14209","article-title":"Hereditary angioedema: the plasma contact system out of control","volume":"16","author":"De Maat","year":"2018","journal-title":"J Thromb Haemost"},{"key":"B4","doi-asserted-by":"publisher","DOI":"10.1016\/j.amjmed.2005.09.064","article-title":"Hereditary angioedema: new findings concerning symptoms, affected organs, and course","volume":"119","author":"Bork","year":"2006","journal-title":"Am J Med"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.1111\/j.1572-0241.2006.00492.x","article-title":"Symptoms, course, and complications of abdominal attacks in hereditary angioedema due to C1 inhibitor deficiency","volume":"101","author":"Bork","year":"2006","journal-title":"Am J Gastroenterol"},{"key":"B6","doi-asserted-by":"publisher","first-page":"28","DOI":"10.1186\/s41065-022-00242-z","article-title":"Mutation update of SERPING1 related to hereditary angioedema in the Chinese population","volume":"159","author":"Wang","year":"2022","journal-title":"Hereditas"},{"key":"B7","doi-asserted-by":"publisher","first-page":"132","DOI":"10.1016\/j.jaip.2020.08.046","article-title":"US HAEA Medical Advisory Board 2020 guidelines for the management of hereditary angioedema","volume":"9","author":"Busse","year":"2021","journal-title":"J Allergy Clin Immunol Pract"},{"key":"B8","doi-asserted-by":"publisher","DOI":"10.1001\/jama.2018.16773","article-title":"Effect of lanadelumab compared with placebo on prevention of hereditary angioedema attacks: a randomized clinical trial","volume":"320","author":"Banerji","year":"2018","journal-title":"JAMA"}],"container-title":["Frontiers in Immunology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fimmu.2026.1828352\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T04:46:27Z","timestamp":1787719587000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fimmu.2026.1828352\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,26]]},"references-count":8,"alternative-id":["10.3389\/fimmu.2026.1828352"],"URL":"https:\/\/doi.org\/10.3389\/fimmu.2026.1828352","relation":{},"ISSN":["1664-3224"],"issn-type":[{"value":"1664-3224","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,26]]},"article-number":"1828352"}}