Case Report Asia Pacific allergy pISSN 2233-8276 · eISSN 2233-8268 http://dx.doi.org/10.5415/apallergy.2013.3.4.285 Asia Pac Allergy 2013;3:285-288 Recurrent intradialytic heparin induced anaphylaxis: workup and management Amelia Santosa 1,3 , Seng Hoe Tan 2 , and Yew Kuang Cheng 2,3,* 1 Division of Rheumatology, University Medicine Cluster, National University Health System, Singapore 119228, Singapore 2 Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore 3 Gleneagles Medical Centre, Singapore 258500, Singapore Heparin has been widely used for intradialytic anticoagulation since the 1940s. Heparin induced anaphylaxis can be life threatening, mandating early recognition and intervention. However, due to its relative rarity many physicians remain unaware. We report the case of a 70-year-old woman requiring dialysis, who developed recurrent anaphylaxis to intradialytic heparin. We describe a systematic approach to confrm the suspected heparin allergy, which must include an evaluation of predisposing factors, the dialysis equipment and concomitant medications. Further workup for safe alternatives employing skin prick and intradermal tests, as well as provocation tests are discussed. Key words: Dialysis; Heparin; Anaphylaxis; Skin tests; Intradermal test; Drug hypersensitivity INTRODUCTION Unfractionated heparin has been widely used as an anticoagulant in end stage renal failure patients requiring hemodialysis since the 1940s [1]. While rare, heparin induced anaphylaxis is a potentially life threatening situation that mandates early recognition and intervention. However, due to its relative rarity [2] many physicians remain unaware. We present such a case, with its subsequent workup and rationale for further management. CASE REPORT A 70-year-old Chinese female with hypertensive kidney disease was deemed to require dialysis. She had no known allergies and never received angiotensin converting enzyme (ACE) inhibitors. Dialysis was commenced through a permanent catheter with 500 U of unfractionated heparin/hr for intradialytic anticoagulation. She tolerated 3 hemodialysis sessions per- week in the initial 2 weeks. The following week she developed hypotension and dyspnea at the start of a dialysis session. First Correspondence: Yew Kuang Cheng Gleneagles Medical Centre, 6 Napier Road #09-02 Singapore 258500, Singapore Tel : +65-6474-9438 Fax : +65-6474-1847 Email : ykcheng@aar-clinic.com Received: August 7, 2013 Accepted: September 30, 2013 This is an Open Access article distributed under the terms of the Creative Commons Attribution. Non-Commercial License (http://creativecommons. org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Copyright © 2013. Asia Pacifc Association of Allergy, Asthma and Clinical Immunology. http://apallergy.org