title: Chlorpheniramine-induced anaphylaxis diagnosed by basophil activation test.
abstract: Chlorpheniramine is a widely prescribed H1-antihistamine for relieving urticaria or histamine-mediated allergic reactions. However, although rare, it may cause immediate hypersensitivity reactions. The diagnosis is usually made by provocation test, but its application is often limited due to comorbidities or potential risk of severe reactions. In those cases, skin tests and basophil activation tests can be considered as additional diagnostic tests for the drug allergy. Here, we report a 33-year-old female with underlying chronic urticaria, who recurrently developed anaphylaxis after chlorpheniramine administration. Intradermal test showed positive responses in the patient at 0.02 mg/mL of chlorpheniramine, but not in healthy controls. Basophil activation test showed significant up-regulation of CD63 and CD203c by chlorpheniramine. The present case reminds the rare but potential allergic risk of chlorpheniramine, and also suggests the potential utility of basophil activation test in making the diagnosis.
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-799, Korea. ; Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul 110-799, Korea.
authors.forename: Hyun-Seung
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-799, Korea. ; Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul 110-799, Korea.
authors.forename: Woo-Jung
authors.initials: WJ
authors.lastname: Song
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-799, Korea. ; Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul 110-799, Korea.
authors.forename: Ji-Won
authors.initials: JW
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-799, Korea.
authors.forename: Young-Yoon
authors.initials: YY
authors.lastname: Cho
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-799, Korea. ; Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul 110-799, Korea.
authors.forename: Han-Ki
authors.initials: HK
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-799, Korea. ; Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul 110-799, Korea.
authors.forename: Min-Gyu
authors.initials: MG
authors.lastname: Kang
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-799, Korea. ; Institute of Allergy and Clinical Immunology, Seoul National University Medical Research Center, Seoul 110-799, Korea.
authors.forename: Sang-Heon
authors.initials: SH
authors.lastname: Cho
authors.affiliation: Department of Internal Medicine, Dongguk University Ilsan Hospital, Goyang 410-773, Korea.
authors.forename: Seong-Wook
authors.initials: SW
authors.lastname: Sohn
keywords: Anaphylaxis; Basophils; Drug Hypersensitivity