DELAYED URTICARIA AND ANGIOEDEMA FOLLOWING YELLOW FEVER VACCINE IMMUNIZATION

Introduction Few cases of acute allergic reaction to Yellow Fever Vaccine (YFV) are reported. We present a case of delayed urticaria and angioedema (U&A) following YFV immunization. Case Description A 51-year-old female with multiple medical problems including history of malignancy presented for evaluation of U&A for over a month. Two days after YFV immunization she developed progressive neurological symptoms over a period of time and eventually was admitted to the hospital. She found to have hypertension, but extensive laboratory and radiology evaluations were not contributory. The patient was treated symptomatically and discharged. Neurological symptoms gradually improved but three weeks after YFV immunization she developed episodic U&A responsive to steroids. Our evaluation revealed normal complement studies, normal functional C1 esterase, no specific IgE to egg or gelatin, negative rheumatological work up and no gross immunodeficiency, although she had elevated CRP and ESR. We advised the patient to stop new medications and treated the U&A. At two month follow up U&A symptoms completely resolved. Reintroduction of medications did not cause U&A. Discussion We suspect that our patient developed delayed non IgE mediated reaction to YFV. Health care providers should take caution administering YFV to patients with an underlying malignancy. A complete medical history is needed to determine risk benefit ratio of YFV immunization.