Anaphylaxis due to burdock

A 53‐year‐old Japanese man, with a history of developing urticaria (once after consuming mackerel and 10 times after consuming boiled burdock, carrot, curry, and rice), presented with redness over his entire body and dyspnea 1 h after eating boiled burdock. Physical examination revealed a low blood pressure of 64/29 mmHg and stridor, together with striking redness of the whole body; he was diagnosed to be in anaphylactic shock. He recovered from the anaphylactic shock with subcutaneous injection of epinephrine (1 mg) and an intravenous drip of lactate Ringer's solution containing hydrocortisone (100 mg) and dexamethasone (8 mg). Laboratory examination and skin prick test were performed 3 weeks after his first visit. The total immunoglobulin E (radioimmunosobent test) level was 190 IU/mL, and specific immunoglobulin E for mackerel and carrot was found to be negative. Skin prick test was performed on the volar forearm with burdock, carrot, and turmeric after he had not taken any medication for 1 week. It was also conducted in normal healthy persons at the same time. A skin prick was made with a PRICK‐LANCETTER® (made in Sweden) using 1% histamine chloride solution and 0.9% saline solution as positive (3+) and negative (–) controls, respectively. For skin prick tests, burdock and carrot were employed in their boiled and raw conditions. Turmeric powder was diluted to 1% and 10% in petrolatum. Skin prick tests were judged according to the recommendations of the European Academy of Allergy and Clinical Immunology (Shono M. The skin test learned in Finland. Hifubyou‐Shinryoh 1999; 25 (3) : 255–269; Bernstein IL. Proceedings of the task force on guidelines for standardizing old and new technologies used for the diagnosis and treatment of allergic diseases. J Allergy Clin Immunol 1988; 82: 487–526). The results of the skin prick tests ( Table 1) were positive for raw and boiled burdock and carrot, but negative for turmeric ( Fig. 1). Two normal healthy controls showed negative responses to all substances. 1 Results of skin prick testWheal size (mm)ScoreBoiled burdock 3 × 4 (3+) Boiled carrot 3 × 3 (3+) Raw burdock 3 × 4 (3+) Raw carrot 3 × 3 (3+) 1% turmeric diluted with petrolatum 0 × 0 (–) 10% turmeric diluted with petrolatum 0 × 0 (–) 1% histamine chloride 4 × 4 (3+) Normal saline – (–)1Skin prick tests performed on the flexor surface of the forearm (left: 1, boiled burdock; 2, boiled carrot; 3, raw burdock; 4, raw carrot; right: 5, 1% turmeric; 6, 10% turmeric; 7, histamine chloride; 8, normal saline) This is the first case report of anaphylaxis due to burdock.