IgE-mediated reactions
Anecdotal evidence suggests that red currant may, in rare instances, induce symptoms of food allergy in sensitised individuals; however, few studies have been reported to date. (1-5)
A 19-year-old woman with a history of urticaria-angioedema in childhood due to sunflower seed and peanut developed malaise, palpebral and genital angioedema, erythema on her face and neck, systemic hives, pruritus, and dysphonia immediately after eating duck meat with red currant sauce. Total IgE was 138 kUA/L. Skin-prick tests were positive for a range of allergens, and prick-by-prick testing was positive to red currant and plum. Specific IgE (kUA/L) was detected to Artemisia vulgaris (1.54); Chenopodium album (0.38); Platanus acerifolia (0.59); strawberry (0.67); apple (3.63); peach (7.71); plum (0.70); onion (0.45); peanut (1.13); chestnut (1.24); walnut (2.82); and pistachio (0.38). Specific IgE to peach Pru p 3 was 17.03 kUA/L. IgE to red currant was positive by enzyme-linked immunosorbent assay; and a single 14 kDa band, identified as a lipid transfer protein, was seen on immunoblot. (2)
The aim of a study conducted at 17 clinics in 15 European cities was to describe the differences between some northern countries regarding self-reported hypersensitivity symptoms from foods. Patients with a history of food hypersensitivity were asked to fill out a questionnaire in which 86 different foodstuffs were listed. ‘Slight symptoms’ were most common with (among others) red currant, which was the 49th-most-reported food resulting in adverse effects, affecting 9.2% of 1 139 individuals. (4)
In a rare case of anaphylaxis, a 47-year-old woman presented with generalised urticaria, dysphagia, dyspnoea, pruritis of the palms and soles, hyptonia, and tachycardia, 2.5 hours after eating red currants. A month later, she developed generalised urticaria after eating black-currant jam. Skin-specific IgE (prick-to-prick) was positive to red currant and black currant. Serum IgE was absent for both. (6)
An earlier report of anaphylaxis to red currant also lacked detectable IgE levels, but exhibited specific IgA and IgM antibodies instead. (6)
A study reported on a 50-year-old woman with allergy to grass pollen and oral allergy syndrome involving several fruits. She presented with pruritus and pharyngeal occupation with dysphagia, while eating fresh red and black currant jam. She reported similar episodes with peach, apricot, and nectarine (jam, juice, and fresh). She tolerated other fruits of the Rosaceae family (i.e. raspberry, plum, apple, and pear). Skin prick-to-prick tests with fresh red and black currants were negative, and positive to peach. Specific IgE to red currant was 5.7 KU/L, and 2.92 KU/L for peach. (1)