Buckwheat allergy in Australia

Buckwheat allergy in Australia Buckwheat as a hidden food allergen is well described. Buckwheat allergy is relatively uncommon in Australia, and the diagnosis may be missed unless there is a high index of suspicion. Due to the avoidance of gluten, buckwheat is increasingly popular in Western countries among individuals with coeliac disease and wheat intolerance. We describe a case series of allergy to buckwheat in South Australia. We collected a consecutive series of cases presenting to the Department of Immunology and Allergy, Royal Adelaide Hospital, and private specialist rooms, with positive skin prick test (saline slurry of buckwheat flour) and/or specific IgE (f11, ImmunoCap Thermo Fisher Scientific, Uppsala, Sweden) to buckwheat from 2012 to 2015. A slurry of approximately 100 mg buckwheat flour in 200 μL 0.9% saline was prepared. A drop of the suspension was then used for skin prick testing. A skin test was considered positive at a wheal size of 3 mm or greater when measured at 15 min. Specific IgE test was positive at 0.35 kU/L or greater. Test was negative in normal controls. Salient demographic information, clinical features and management plan were collected. This observational study was approved by the Ethics Committee of the Royal Adelaide Hospital. Eight patients presented with an acute allergic reaction or anaphylaxis shortly following ingestion of food containing buckwheat. Clinical features ranged from generalised urticaria with angioedema to hypotensive and life-threatening anaphylaxis. Buckwheatcontaining foods triggering reactions were pancakes, muesli bars, cereal grains, crackers, bread, milk shakes with grains, muffins, galette and crepes. Such foods were labelled gluten-free in one out of eight known cases. One particular case presented with recurrent anaphylaxis shortly after breakfast. Two atopic individuals working in the food industry (one baker and one involved in meal preparation) experienced occupational rhinitis responding to antihistamines. Neither was known to be allergic to food although their specific tolerance or otherwise of buckwheat was unknown. Demographic and clinical information and results of diagnostic investigations are shown in Table 1. Despite its name, buckwheat (Fagopyrum esculentum) is taxonomically unrelated to wheat. It is not a grass therefore not a true cereal. It is grown worldwide and is commonly consumed in certain parts of Asia and Europe. The flour is widely used in traditional Japanese (soba noodles), Korean (guksu), Italian (pizzoccheri and polenta taragna) and Russian cooking (pancake-blinis). Due to common consumption in Eastern Asia and Northern Italy, it is unsurprising that most cases of buckwheat allergy have been reported from these regions. A 40–50 kDa protein has been implicated as an important allergen to predict moderate-to-severe clinical symptoms in Korean children with buckwheat allergy. Allergic reactions may range from cutaneous manifestations to life-threatening anaphylaxis. Clinical reactivity may occur following oral ingestion or inhalant exposure, including asthma exacerbations from use of pillow containing buckwheat fillers. Buckwheat exposure may pose an occupational health risk in the baking or noodle-making industry where inhalation of buckwheat dust from grinding and packaging causes respiratory symptoms such as occupational asthma. Buckwheat-triggered occupational rhinitis