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Adverse reactions associated with Echinacea: the Australian experience
Mullins RJ, Heddle R, John James Medical Centre, Deakin, ACT, Australia
Background: 50% of Australians use complementary and alternative medicines (other than vitamins) in any 12-month period, of which Echinacea-containing products are increasingly popular. Recent reports have highlighted the risk of allergic reactions to complementary medicines in atopic patients.
Objective: To determine the characteristics of complementary medicines in atopic patients.
Methods: Five privately referred patients were evaluated by the authors in their office private practices via skin prick testing (SPT) and RAST after adverse reaction to Echinacea. As there was little published information on adverse reaction to Echinacea, reports to the Australian Adverse Drug Reaction Advisory Committee were reviewed. Those suggestive of possible allergic reactions were evaluated in greater detail by anonymously surveying the healthcare professionals who had reported the cases and from one unreported case. Serum was collected for further analysis where possible.
Results: the authors personally evaluated 5 cases of adverse reactions to Echinacea. 2 patients suffered anaphylaxis and a third had an acute asthma attack 10 minutes after their first ever dose of Echinacea. The fourth patient suffered recurrent episodes of mild asthma each time Echinacea was ingested, and the fifth developed a maculopapular rash within 2 days of ingestion, which recurred when rechallenged. Three of the patients had positive SPT results. Three reported repeated spontaneous ?€challenge" and symptoms after further ingestion of Echinacea. 51 Australian adverse drug reports implicating Echinacea were also reviewed. There were 26 cases suggestive of possible IgE-mediated hypersensitivity (4 anaphylaxis, 12 acute asthma, 10 urticaria/angioedema). Of these 26 patients, age ranged from 2 to 58 years, 78% were female and >50% were known to be atopic. Four were hospitalised, 4 reacted after their first known exposure, and 1 patient suffered multiple progressive systemic reactions. 20% of 100 subjects who had never taken Echinacea also had a positive SPT result to this substance when tested by one of the authors in his office practice.
Conclusion: Some atopic subjects have positive SPT results to Echinacea in the absence of known exposure. Atopic subjects are also over-represented in those experiencing reactions to Echinacea. The possibility that cross-reactivity between Echinacea and other environmental allergens may trigger allergic reactions in "echinacea-naive" subjects is supported by the Australian data. Given its widespread (and largely unsupervised) community use, even rare adverse events become inevitable. Atopic patients should be cautioned appropriately.
Reference: Annals Asthma Immunol 2002 Jan;88:42-51
Clinical cross-reactivity among foods of the Rosaceae family
Julia Rodriguez, MD et al, Madrid, Spain
Background: Foods from the Rosaceae botanical family have been increasingly reported as causes of allergic reaction. Patients frequently have positive skin tests or RAST results for multiple members of the botanical family.
Objective: Our purpose was to investigate the clinical cross-reactivity assessed by double-blind, placebo-controlled food challenge (DBPCFC) of Rosaceae foods (apricot, almond, plum, strawberry, apple, peach, pear).
Methods: 34 consecutive adult patients complaining of adverse reactions to Rosaceae were included in the study. Skin prick tests and CAP System (FEIA) were performed with Rosaceae foods in all patients. Clinical reactivity to Rosaceae was systematically evaluated by open food challenges (OFCs), unless there was a convincing history of a recent severe anaphylaxis. Positive reactions on OFCs were subsequently evaluated by DBPCFs.
Results: 26 and 24 patients had positive skin prick tests and CAP FEIA with Rosaceae, respectively; from these 88% and 100% had positive tests with >2. No evidence of reactivity was found in 66% of positive skin prick tests and 63% of positive specific IgE determinations to fruits. A total of 226 food challenges (including OFC and DBPCFC) were performed in the 28 patients with positive skin prick tests or CAP System FEIA. Of the 182 initial OFCs carried out, 26 (14%) reactions were confirmed by DBPCFCs. Overall, 40 reactions were considered positive in 22 patients with positive skin tests of CAP FEIA. 38 reactions had been previously reported, the remaining 2 were detected by systematic challenges. Most reactions were caused by peach (22 patients), apple (6), and apricot (5). Ten patients (46%) were clinically allergic to peach and other Rosacea.
Conclusion: Positive skin test and CAP System FEIA should not be taken as the only guide for multi-species dietary restrictions. Nevertheless, the potential clinical allergy to other Rosacea should not be neglected. If the reported reaction is confirmed, current tolerance to other Rosacea should be precisely established unless there has been ingestion without symptoms after the reaction.
Reference: J Allergy Clin Immunol 2000; 106:183-9.
Peels of Rosaceae fruits have a higher allergenicity than pulp
Fernandez-Rivas M, Cuevas M, Allergy Unit, Hospital Ntra. Sra. de Sonales, Avila
Background: It is not uncommon that patients allergic to fruits such as apple, pear, and peach, refer adverse reactions after ingestion of the whole fruit, but subsequently tolerate the pulp.
Objective: This study aimed to compare the allergenicity of peels and pulps of apple, peach, and pear in 33 patients allergic to these fruits.
Methods: Clinical reactivity to the ingestion of whole fruit (peel + pulp) and pulp was established by medical history. Peels and pulps were tested separately in skin prick tests (SPTs), histamine release tests (HRTs) and RASTs. Cross-allergenicity between peel and pulp of apple and peach was studied by RAST inhibition.
Results: Adverse reactions occurred more frequently and were more severe when the whole fruit was eaten. More than 40% of patients allergic to apple and pear tolerated the ingestion of the pulp of these fruits, and reactions were only elicited by the intake of the whole fruit. Peels induced higher SPTs, HRTs and RASTs than pulps. An important cross-allergenicity was found between the peel and pulp of apple and peach, although the amount of shared allergenic epitopes seemed to be higher in peels.
Conclusion: Their results suggest that peels of Rosaceae fruit such as apple, peach, and pear, have a higher allergenicity than pulps, which is clinically relevant. This aspect should be considered in the evaluation of patients allergic to Rosaceae fruits, and in the production of diagnostic materials.
Reference: Clin Exp Allergy 1999 Sep; 29 (9):1239 - 47
Fennel, cucumber, and melon allergy successfully treated with pollen-specific injection immunotherapy
Ricardo Asero, MD
Background: In subjects with both pollinosis and vegetable food allergy, most allergenic epitopes of fruits are present in pollen. A recent study showed marked reduction or total disappearance of apple-induced oral allergy syndrome in patients receiving injection immunotherapy with birch pollen extracts.
Objective: To assess whether vegetable food allergy following other kinds of primary pollinosis may be successfully treated with pollen-specific immunotherapy.
Methods: A 34-year-old woman with long-standing pollinosis and typical oral allergy syndrome (OAS) with the ingestion of both fennel and cucumber and whose OAS was associated with laryngeal oedema after the ingestion of melon, was treated with 2 commercial depot aluminium hydroxide-adsorbed extracts of grass pollen and mugwort pollen 50% + ragweed pollen 50%.
Results: After 36 months of injection specific immunotherapy, the patient was able to tolerate both fresh fennel and cucumber without consequence on open oral challenge tests. After 43 months of immunotherapy, the patient tolerated fresh melon as well on open oral challenge. She has re-introduced these vegetables in her normal diet. Skin tests show no reactivity to fresh fennel and there was a reduction of the wheal induced by fresh cucumber.
Conclusion: Vegetable food allergy following primary sensitisation to pollens, other than birch, may also be effectively reduced by pollen-specific injection immunotherapy.
Reference: Annals of Allergy, Asthma & Immunology 2000;84:460-462
Seasonal variation in food allergy to apple
Skamstrup Hansen K, et al, National Univ Hosp., Copenhagen, Denmark
Objective: The aim of the study was to investigate the possibility of a seasonal variation in reactivity to apples in 27 birch pollen allergic patients.
Methods: Before and during the birch pollen season 1998, the patients were subjected to double-blind, placebo-controlled food challenges (DBPCFCs) with grated whole fresh Golden Delicious apple followed by an open challenge with whole fresh apple. The clinical reactions elicited during the challenges were evaluated both by the patients and the investigators. Moreover, the skin reactivity and the in vitro reactivity to apple were evaluated by skin prick test (SPT), leukocyte histamine release (HR), measurement of specific IgE (RAST), and immunoblotting experiments.
Results: The sensitivity of the DBPCFC, when compared with the result of the open challenge, 0.74 (14/19) before the season and 0.80 (16/20) during the season. None of the patients reacted to the blinded challenge without a subsequent reaction to the open challenge. One placebo reaction was registered both before and during the season, but not in the same patient. The patient scores of the first positive challenges, and the maximal scores of each combined blinded and open challenge session, were significantly increased during the pollen season (p<0.05). The scores of the open challenge were significantly higher than the scores of the DBPCFC both before the season and during the in-season challenges (p<0.05). Specific IgE against Golden Delicious increased during season (p<0.05), while neither SPT, HR, nor immunoblotting experiments could confirm an increase in reactivity.
Conclusions: The results of the oral challenge test indicated an increase in clinical reactivity to apples during the birch pollen season in birch pollen allergic individuals.
Reference: J Chromotogr B Biomed Sci Appl 2001 May 25; 756 (1-2): 19-32
Anaphylactic reaction to young garlic
Perez-Pimiento et al, Servicio de Alergia, Clinica Puerta de Hierro, Madrid, Spain
Background: Garlic is well known to cause contact dermatitis and asthma. However, it is a very rare cause of food allergy. This is a case of a 23-year-old woman with previous history of allergy to pollen and dried fruit, and food-dependent, exercise-induced anaphylaxis for which no specific food could be identified as responsible, who experienced an anaphylactic reaction after eating young garlic.
Methods: Skin prick tests and specific IgE immunoassay with several pollens and foods were performed, as well as the prick-prick test with young garlic and sds-PAGE followed by immunoblotting IgE to young garlic and other Liliaceae species, mustard, sesame, parsley, celery, hazelnut, almond, and pollen to birch and mugwort.
Results: Skin prick tests and Specific IgE were mainly positive for grass, plane tree, and mugwort pollen; peanut; hazelnut; walnut; almond; and mustard. Prick-prick test with young garlic and garlic were positive. Total IgE was 113U/ml. SDS_PAGE immunoblotting showed IgE-binding bands at 12kDa to young garlic, garlic, onion, and leek extracts. Similar bands could also be detected with mugwort pollen and hazelnut extract.
Conclusions: They described IgE-mediated reaction to young garlic in a patient sensitised to pollen and dried fruit.
Reference: Allergy 1999 Jun; 54(6):626-9
Systemic allergic reaction to coconut (Cocos nucifera) in 2 subjects with hypersensitivity to tree nut and demonstration of cross-reactivity to legumin-like seed storage proteins: New coconut and walnut food allergens.
Suzanne S. Teuber MD & W. Rich Peterson BS, Pleasant Hill and Davis, Calif
Background: Two patients with tree nut allergy manifested by life-threatening systemic reactions reported the subsequent onset of systemic reactions after consumption of coconut.
Objective: Herein, the IgE-binding proteins from coconut are described, and in vitro cross-reactivity with other nuts is investigated.
Methods: The IgE-binding profile of coconut endosperm tissue extract was analysed by SDS-PAGE followed by immunoblotting. Immunoblot inhibition studies with walnut, almond, peanut, and coconut were performed.
Results: Sera IgE from both patients recognized reduced coconut allergens with molecular weight of 35 and 36.5kd. IgE from 1 patient also bound a 55-kd antigen. Preabsorbtion of sera with nut extracts suppressed IgE binding to coconut proteins. Preabsorbtion of sera with coconut caused the disappearance of IgE binding to protein bands at 35 and 36 kd on a reduced immunoblot of walnut protein extract in 1 patient and supression of IgE binding to a protein at 36 kd in the other patient.
Conclusions: The reduced coconut protein at 35 kd was previously shown to be immunologically similar to soy glycinin (legumin group of seed storage protein). The clinical reactivity in these 2 patients is likely to be due to cross-reacting IgE antibodies primarily directed against walnut, the original clinical allergy reported, and most likely to walnut legumin-like protein. Coconut allergy in patients with tree nut allergy is rare; these are the first 2 patients ever reported, and therefore there is no general indication to advise patients with tree nut allergy to avoid coconut.
Reference: J Allergy Clin Immunol 1999; 103:1180-5
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