Lupin sensitization and clinical allergy in food allergic children in Norway

AIM: The aim of the present pilot study was to investigate to what extent children in Norway sensitized to lupin had clinical lupin allergy, and to compare sensitization to lupin with sensitization to other legumes. METHODS: Thirty-five children with food allergy referred to a national referral hospital were evaluated with skin prick test (SPT) and analysis of serum-specific IgE to lupin, peanut, pea and soy. The children with positive SPTs to lupin were offered oral food challenges with lupin flour. RESULTS: Fifteen children (43%) had positive SPT and 17 children (49%) had serum-specific IgE to lupin. Ten SPT-positive children underwent oral food challenges and one experienced an allergic reaction to lupin flour. This child was one of six challenged children with IgE antibodies to peanut >15 kU(A)/L. There was a strong relationship between positive SPT to lupin flour and positive SPT to soy and between positive SPT to lupin and specific IgE to soy, pea and peanut. CONCLUSIONS: Children with sensitization to lupin are not likely to have a clinical lupin allergy. Avoidance of lupin on the basis of lupin sensitization or peanut allergy would lead to unnecessarily strict diets. Food challenge is currently necessary to diagnose lupin allergy.     

Development of latex allergy in children up to 5 years of age - a retrospective analysis of risk factors

The aim of the study was to investigate possible associations between the time course of early sensitization to latex and various life style factors. Of the 398 children from a prospective birth cohort study, 20 (5%) showed specific serum IgE to latex at the age of 5 years. Sensitization started beyond the first year of life and 19 out of 20 sensitized children showed increasing specific IgE-values over time. All 20 sensitized children were atopic (p < 0.00000). Total IgE was significantly higher in the sensitized group (median 394.5 kU/I) than in the non-sensitized group (median 39.2 kU/1) (p < 0.00001). Comparing the latex-sensitized group with the non-sensitized children, there were significantly more operations in the latex group (p < 0.05) during the first 5 years of life. Medical history, certain foods, the use of pacifiers, mattress composition and socio-economic data proved not to be significant risk factors. From our study we conclude that -besides the number of operations and an atopic predisposition - no other definite risk factor for developing sensitization or allergy to latex (such as everyday household objects) can be identified in children up to 5 years of age.     

IgE antibody responses in young children with atopic dermatitis

In 2184 young children aged 13–24 months with atopic dermatitis (SCORAD 5–59) serum IgE antibodies to a standard panel of food and inhalant allergens were assayed. The frequency of positive IgE responses (>0.35 kU/l) increased with greater severity of skin disease. A significant minority of infants had levels of IgE antibody to foods to suggest they were at risk of acute reaction to those foods (7% to hen's egg, 3% to cow's milk, 4% to peanut). Our findings indicate that the frequency of positive IgE responses is related to disease severity and suggest that differences in the time course of the development of IgE responses to food, which are at maximum prevalence within the first year of life, while inhalant allergies, are still developing between 1 and 2 yr and beyond.     

The development of atopic sensitization in Estonian infants

In a prospective study, 251 infants were followed from birth up to 12 months of age, recording manifestations of allergy by questionnaires at 3, 6, 9 and 12 months and by clinical examinations at 6 and/or 12 months. Blood samples were obtained at birth and at 6 and 12 months and analysed for serum lgE levels. The children were skin-prick tested with foods at 6 and 12 months of age and with inhalant allergens at 12 months. Blood samples from SPT-positive individuals and controls were analysed for the presence of IgE antibodies to common inhalant allergens and their cord sera for the presence of IgE antibodies to cow's milk and egg. Twelve infants (7%) were sensitized against foods [3 to cow's milk (CM) and 9 to egg white (EW)] at 6 months and 11 (5%) (2 to CM and 9 to EW) at 12 months. Seventeen infants (7%) had IgE antibodies against inhalant allergens at 6 and/or 12 months, as determined by either SPT and/or the demonstration of circulating IgE antibodies. Out of 30 children with positive SPT and/or circulating IgE antibodies against foods and inhalant allergens at any age, 6 had atopic dermatitis, 4 gastrointestinal food allergy, 1 urticaria and 4 probable allergy, while 15 had no clinical manifestation of allergy. Immunoglobulin E antibodies against Ascaris were detected in 17% of the infants with S-IgE levels >20kU/l. The study indicates that the incidence of sensitization and manifestations of allergic disease is similar among Estonian and Scandinavian infants during the first year of life. Given earlier findings indicating a significantly higher prevalence of atopic disease in Scandinavian school-children relative to their counterparts in Eastern Europe, the present study suggests that the key events which determine disease expression do not occur exclusively during the first year of life.     

Skin prick test predictive value on the outcome of a first known egg exposure in milk-allergic children

Children with milk allergy have higher incidence of other food allergies, especially egg allergy. The objective of this study was to ascertain the accuracy of the prick test in children with IgE-mediated milk allergy for diagnosing egg allergy. Children under the age of 1 yr who came consecutively to Allergy Department 2003–05, and were diagnosed with IgE-mediated milk allergy were selected for this study. Egg introduction was completely avoided until the age of 14 months when clinical history, skin prick tests (SPT), specific-IgE antibodies determination and egg challenge test were performed. One hundred and four milk-allergic children were included. At least one positive prick test to any egg allergen was found in 65 out of the 104 (62.5%). Thirty-eight (36.5%) were allergic to egg proteins as well. Prick tests with egg white and ovomucoid (OVM) had the best diagnostic performances showing the largest areas under the receiver operating characteristic curve. The optimal diagnosis cut-off point was 6 mm for egg white and 5 mm for OVM. The positive likelihood ratios for these cut-off points were: 2.95 (95% CI: 1.74–4.99) for egg white prick test, and 20 (95% CI: 2.9–143.7) for OVM prick test. Children with specific IgE-mediated cow's milk allergy must be closely followed as a risk group for egg allergy. Early diagnosis is necessary and the SPT has shown itself to be a very useful tool for diagnosing immediate IgE reactions to egg on first known exposure.     

Patterns of latex allergen recognition in children sensitized to natural rubber latex

Single recombinant latex allergens permit the study of the pattern of sensitization to individual allergens. We aimed to quantify the IgE-response to individual latex allergens in children sensitized to latex. The study group included 31 latex-sensitized children: 26 operated at least twice, 20 of them with spina bifida; two children with one operation and three atopic non-operated children. IgE antibodies to rHev b 1, rHev b 3, rHev b 5, rHev b 6.01, rHev b 7.02 and rHev b 8, coupled to ImmunoCAPs, were measured in each serum. IgE responses to rHev b 1, rHev b 5 and rHev b 6.01 were found in 17 children each, and their mean +/- s.d. levels were 5 +/- 7.4, 16.8 +/- 14 and 10 +/- 18 kU/l, respectively. IgE responses to rHev b 3 (4 +/- 5.4 kU/l) were found in eight children. Two children had IgE to rHev b 7 (1.7 and 3.2 kU/l), and none to rHev b 8. Four sera were negative to all tested recombinant allergens. We divided the patients in three groups: sensitized only to rHev b 1, sensitized only to rHev b 5 and/or rHev b 6.01, and sensitized to both rHev b 1 and to rHev b 5 and/or rHev b 6.01. The three groups had the same profile of clinical features. Hev b 5 induces the quantitatively higher IgE responses in children with multiple surgeries sensitized to latex. Responses to Hev b 6.01 equal those of Hev b 1.     

Natural rubber latex allergy: prevalence and risk factors in patients with spina bifida compared with atopic children and controls

Type 1 allergy against natural rubber latex is an increasing problem in health care workers and children with spina bifida or urogenital malformations. The aim of our study was to evaluate the prevalence of latex IgE antibodies and cross-reacting fruit antibodies in patients with spina bifida compared with atopic and non-atopic controls. Risk factors for sensitization should be determined. Sera of 148 patients with spina bifida and 98 controls (44 with atopy) were screened for IgE antibodies against latex, banana and kiwi by fluorescence enzyme immunoassay (CAP system). Atopies, allergic symptoms after latex contacts and the number of operations were compiled by a questionnaire. Patients with spina bifida developed latex IgE antibodies (≥0.7 kU/l) more frequently (40.5%) than atopic children (11.4%) or healthy controls (1.9%). All 18 symptomatic patients belonged to the spina bifida group and had high values of latex antibodies. The risk for developing latex antibodies increases with the number of operations. There was no difference in the history of atopic diseases and in a screening test of IgE antibodies against inhalative allergens between latex sensitized and not sensitized children with spina bifida. Antibodies against banana were more frequent in the latex sensitized children with spina bifida. (18.3% vs 3.4%, P = 0.002). Conclusion The high prevalence of latex antibodies in children with spina bifida justifies a primary prophylaxis by avoiding latex contacts, especially during anaesthesia and surgery, a correlation between the number of operations and the development of latex antibodies exists. Received: 30 March 1996 and in revised form: 19 March 1997 / Accepted: 20 March 1997     

Shellfish allergy in children

Food allergies affect approximately 3.5–4.0% of the world's population and can range from a mere inconvenience to a life-threatening condition. Over 90% of food allergies in childhood are caused by eight foods: cow's milk, hen's egg, soy, peanuts, tree nuts, wheat, fish, and shellfish. Shellfish allergy is known to be common and persistent in adults, and is an important cause of food induced anaphylaxis around the world for both children and adults. Most shellfish-allergic children have sensitivity to dust mite and cockroach allergens. Diagnostic cut-off levels for skin prick testing in children with shrimp allergy exist but there are no diagnostic serum-specific immunoglobulin E (IgE) values. All patients with symptoms of IgE-mediated reactions to shellfish should receive epinephrine autoinjectors, even if the initial symptoms are mild. In this study, we review three cases of clinical presentations of shellfish allergy in children.     

Follow up study of cow's milk protein intolerant infants

Over a period of 4 years, 88 infants with cow's milk protein intolerance (CMPI) were followed prospectively in order to evaluate the persistence of CMPI and its relationship between either serum IgE levels or RAST results for cow's milk. After exclusion of lactose intolerance, two positive cow's milk elimination challenge tests were considered diagnostic for CMPI. At the age of 1, 2, 3 and 4 years respectively, 85%, 78%, 49% and 33% of the children still were cow's milk intolerant. Initial serum values of IgE 10 kU/l indicated a late development of tolerance to cow' milk proteins. At the age of 4 years, 90% of infants with initial IgE levels <10 k U/l had become tolerant to cow's milk while this was the case for only 47% of infants with initial IgE levels 10 k U/l. Initial RAST results for cow's milk bore no obvious relationship to outcome.     

Prediction of the development of tolerance to milk in children with cow's milk hypersensitivity

OBJECTIVES: To investigate whether the development of tolerance to cow's milk (CM) by aged 4 years can be predicted with a skin prick test (SPT) and measurements of total or specific immunoglobulin E (IgE) in the serum, taken at the time of diagnosis of cow's milk hypersensitivity (CMH). STUDY DESIGN: Infants with immediate (n=95) or delayed (n=67) challenge reactions to CM were prospectively followed to aged 4 years. CMH status was assessed annually by CM challenges. RESULTS: By aged 2, 3, and 4 years, children with delayed reactions developed tolerance to CM faster than those with immediate reactions: 64%, 92%, and 96% versus 31%, 53%, and 63%, respectively. A wheal size of <5 mm in SPT correctly identified 83% of 124 infants who developed tolerance to CM by aged 4 years, and a wheal size of >or=5 mm in SPT correctly identified 71% of 39 infants with persistent CMH. Milk-specific IgE <2 kU/L correctly identified 82% of infants who developed tolerance to CM, and milk-specific IgE >or=2 kU/L correctly identified 71% of infants with persistent CMH. CONCLUSION: SPT and milk-specific IgE in the serum are useful prognostic indicators of the development of tolerance to CM in infants with CMH.     

Sensitization to turnip rape and oilseed rape in children with atopic dermatitis: a case-control study

Turnip rape and oilseed rape 2S albumins are new allergens in children with atopic dermatitis suspected for food allergy. We recently found that 11% (206/1887) of these children had a positive skin prick test to seeds of oilseed rape ( Brassica napus ) and/or turnip rape ( Brassica rapa ). In the present case-control study we examined how the children with atopic dermatitis sensitized to turnip rape and oilseed rape had been breast-fed and whether they had some common sensitization pattern to certain foods or pollens. A total of 64 children with atopic dermatitis and a positive skin prick test to turnip rape and/or oilseed rape (≥5 mm) were examined. Sixty-four age- and sex-matched children with atopic dermatitis but negative skin prick tests to turnip rape and oilseed rape served as case controls. The turnip rape and/or oilseed rape sensitized children with atopic dermatitis had significantly more often positive skin prick tests reactions and IgE antibodies to various foods (cow's milk, egg, wheat, mustard; p < 0.01) and pollens (birch, timothy, mugwort; p < 0.01) than the control children. They had been exclusively breast-fed for a longer period (median 4 months; p < 0.05) and had more often associated asthma (36%) and allergic rhinitis (44%). Children with atopic dermatitis sensitized to oilseed rape and turnip rape had high frequency of associated sensitizations to all foods and pollens tested showing that oilseed plant sensitization affects especially atopic children who have been sensitized to multiple allergens.     

Total IgE in urban Black South African teenagers: The influence of atopy and helminth infection

Total IgE levels are usually elevated in allergic diseases, being highest in atopic eczema, followed by atopic asthma and allergic rhinitis. Genetic factors are believed to play a role in total IgE levels, with higher levels seen in Black African subjects. Total IgE is also raised in parasite infection. Thus, the higher total IgE levels in Black Africans could be because of environmental rather than genetic factors. Few studies have investigated the usefulness of total IgE levels in the evaluation of atopy in Black Africans. The objective of this study was to determine the total IgE levels in unselected urban Black African high school children and to correlate this with atopy and ascaris sensitization. Atopic status was assessed by means of specific allergen sensitization (skin prick tests to eight inhalant and four food allergens), self-reported asthma and bronchial hyper-responsiveness measured by methacholine challenge. Ascaris sensitization was assessed by means of ascaris IgE measured by CAP-RAST. Total IgE levels were markedly skewed toward the left and were not distributed in a Gaussian or a log-normal distribution. Skin prick tests were positive for aeroallergens in 32.3% of subjects. Thirty four percent had elevated ascaris IgE. Total IgE was higher in atopic vs. non-atopic subjects and correlated with the number of positive skin prick tests, self-reported asthma and bronchial hyper-responsiveness. Subjects without allergy (or) atopy had a median total IgE of 80–90 kU/I. In addition total IgE correlated with ascaris IgE. Subjects with no ascaris sensitization had median total IgE of 77.1 kU/l. Subjects with neither atopy/asthma nor ascaris sensitisation had a median total IgE of 69.9 kU/I, similar to the levels seen in people of other genetic origins. This study suggests that helminthic infection rather than genetic differences, may be the major determining factor of IgE levels in certain populations.     

Cow's milk allergic children can present sensitisation to probiotics

Aim: To evaluate sensitivity to different probiotics in children with cow's milk allergy.
Methods: Eighty-five patients (age range: 4 months –12 years) presenting atopic dermatitis (AD) were enrolled. Skin prick test (SPT) responses to three different probiotics preparations (Fiorilac®, Dicoflor® and Reuterin®) were evaluated in addition to relevant food allergens.
Results: Thirty-nine patients out of 85 (45.8%) had a positive skin response to prick test for cow's milk (3 with reaction <3 mm). Of the thirty-six patients with a cow's milk weal reaction >3 mm, twenty-eight (77.8%) had a skin response to Fiorilac®, four patients (11%) to Dicoflor® and four (11%) to Reuterin®. The proportion of SPT reaction to all the investigated probiotics preparations was significantly lower than cow's milk (r = 9.406; p = 0.002). A significantly higher sensitization was observed for Fiorilac® versus Dicoflor® (r = 30.916; p < 0.001) and versus Reuterin® (r = 34.133; p < 0.001).
Conclusion: Probiotic use in patients with cow's milk allergy has to be limited to products that do not contain milk. This should be clearly reported in the label. In selected patients, it is advisable to perform a screening SPT with the product to evaluate its potential contamination with milk.     

Correlation between specific immunoglobulin E levels and the severity of reactions in egg allergic patients

Different studies proposed specific immunoglobulin E (IgE) cut-off levels for the diagnosis of egg allergy. Little is known if IgE titres could be helpful for prediction of the severity of the reaction. The aim of this study was to determine whether IgE titres are associated with the severity of the reaction during a standardized egg challenge. We reviewed data obtained during oral challenge tests to egg performed between 2003 and 2005, and attributed a clinical score to the positive reactions. Serum specific IgE levels were analysed in relation with the severity of the reaction. We analysed data from 51 oral food challenges to egg, raw or cooked. Sixteen challenges (31%) were negative and 35 (69%) were positive of which 13 challenges (37% of positive reactions) elicited a severe reaction. IgE levels in our patients ranged from undetectable to 14.90 kU/l. We could determine a cut-off level of 8.20 kU/l for a 90% probability of clinical reactivity. IgE titres were statistically significantly different between the patients with absent, mild and moderate or severe reaction. Patients with negative challenge had IgE levels between 0.35 and 6.41 kU/l (median 1.17), those with mild and moderate reaction had IgE levels ranging from 0.35 to 14.90 (median 2.47) and patients with severe reactions had IgE between 1.18 and 11.00 (median 3.70) (p = 0.006). Our results show a correlation between IgE titres and the severity of the clinical reaction to egg. IgE titres may help to determine the potential risk of a reaction to eggs.     

Sensitization to food allergens in Iranian children with mild to moderate persistent asthma

Background

Asthma is the most common chronic respiratory disease in childhood. The clinical presentation of asthma may worsen after food allergen ingestion in sensitized patients. To avoid nonspecific dietary restrictions in children with asthma, laboratory-based advice about foods is potentially helpful. The purpose of this study was to determine food sensitization in children with asthma.

Methods

Seventy-nine children with mild to moderate persistent asthma were included in this study. Commercial food allergens including cow??s milk, egg white, almond, potato, and soybean were used in skin prick tests. Specific IgE to 20 common food allergens was also measured in serum.

Results

Twelve (15.2%) of the patients had a positive skin prick test to at least one of the five food extracts. Sensitization was detected by skin prick tests to cow??s milk and egg white (each 6.3%), almond (3.8%), potato (2.5%) and soybean (1.3%). Specific IgE levels ??0.35 kAU/L were detected in the serum of 47% of the children with asthma. The most common food allergens were cow??s milk (26.6%), hazelnuts (25.3%), wheat flour (15.2%) and egg white (12.6%). Patients with a history of at least one hospital admission due to asthma attack had a higher rate of sensitization to egg.

Conclusions

In our study, food sensitization was frequent in Iranian children with asthma. Although clinical food allergy could not be evaluated because food challenge tests were not used in our study, skin prick tests and serum-specific IgE to common food allergens might be helpful in identifying children with food sensitization.     

The diagnosis of IgE-mediated food allergy in childhood

IgE-mediated food allergy is a common condition in childhood and a recognized public health concern. An accurate diagnosis of food allergy facilitates the avoidance of the allergen – and cross-reactive allergens – and allows for safe dietary expansion. The diagnosis of food allergy relies on a combination of rigorous history, physical examination, allergy tests [skin prick tests (SPT) and/or serum-specific IgE] and oral food challenges. Diagnostic cut-off values for SPT and specific IgE results have improved the diagnosis of food allergy and thereby reduced the need to perform oral food challenges. This clinical case series seeks to highlight a contemporary approach to the diagnosis of food allergy in children strategies.     

The diagnostic value of skin prick testing in children with food allergy

The diagnostic accuracy of the skin prick test (SPT) in food allergy is controversial. We have developed diagnostic cut-off levels for SPT in children with allergy to cow milk, egg and peanut. Based on 555 open food challenges in 467 children (median age 3.0 yr) we defined food-specific SPT weal diameters that were '100% diagnostic' for allergy to cow milk (>or=8 mm), egg (>or=7 mm) and peanut (>or=8 mm). In children < 2 yr of age, the corresponding weal diameters were >or=6 mm, >or=5 mm and >or=4 mm, respectively. These SPT cut-off levels were prospectively validated in 90 consecutive children 相似文献   

Correlation between early neonatal diet and atopic symptoms up to 5-7 years of age in very low birth weight infants: follow-up of randomized, double-blind study

The influence of early feeding on the risk of atopic diseases has been studied in full-term newborns, not in very low birth weight infants (VLBW). The study evaluated effect of early feeding of VLBW infants with either cow's milk-based formula (CMF) or extensively hydrolyzed milk formula (HF) on incidence of atopic diseases and markers of atopy at 5-7 years of age. This was a follow-up of the randomized, double-blind study evaluating the influence of different enteral feeding protocols on the early morbidity of VLBW infants. In the original study 80 children were randomly allocated into 2 groups receiving during first month of life HF (experimental group) or CMF (control group). At the age of 5-7 years, 62 children among 74 available (84%) with mean birthweight 1124g were evaluated according to standardized ISAAC (International Study of Asthma and Allergies in Childhood) protocol. Total IgE level, specific IgE, lymphocyte CD4+CCR4+/CD4+CXCR3+ ratio and skin prick tests (SPT) were done. Prevalence of obvious allergic diseases was not significantly different between the studied groups (HF: 12/33; CMF: 6/29; RR [relative risk] HF vs CMF: 1.76; 95%CI [confidence interval]: 0.76–4.09). Comparison of atopic status across groups revealed similar rate of positive markers of atopy: IgE (RR: 2.57 95%CI: 0.91–8,08), SPT (RR: 5.13; 95%CI: 0.93–31.6), lymphocyte CD4+CCR4+/CD4+CXCR3+ ratio (OR: 2.32; 95%CI: 0.78–7.53) in the both studied groups. Based on the carried out follow-up study we were unable to confirm the usefulness of hydrolyzed formula in prevention of allergy in an unselected cohort of very low birth weight infants.     

Sensitization to turnip rape and oilseed rape in children with atopic dermatitis: a case-control study.

Turnip rape and oilseed rape 2S albumins are new allergens in children with atopic dermatitis suspected for food allergy. We recently found that 11% (206/1887) of these children had a positive skin prick test to seeds of oilseed rape (Brassica napus) and/or turnip rape (Brassica rapa). In the present case-control study we examined how the children with atopic dermatitis sensitized to turnip rape and oilseed rape had been breast-fed and whether they had some common sensitization pattern to certain foods or pollens. A total of 64 children with atopic dermatitis and a positive skin prick test to turnip rape and/or oilseed rape (>or=5 mm) were examined. Sixty-four age- and sex-matched children with atopic dermatitis but negative skin prick tests to turnip rape and oilseed rape served as case controls. The turnip rape and/or oilseed rape sensitized children with atopic dermatitis had significantly more often positive skin prick tests reactions and IgE antibodies to various foods (cow's milk, egg, wheat, mustard; p < 0.01) and pollens (birch, timothy, mugwort; p < 0.01) than the control children. They had been exclusively breast-fed for a longer period (median 4 months; p < 0.05) and had more often associated asthma (36%) and allergic rhinitis (44%). Children with atopic dermatitis sensitized to oilseed rape and turnip rape had high frequency of associated sensitizations to all foods and pollens tested showing that oilseed plant sensitization affects especially atopic children who have been sensitized to multiple allergens.     

Sesame food allergy and sensitization in children: the natural history and long-term follow-up

Sesame food allergy (SFA) in children is an increasingly recognized one in many countries. Our objective was to describe the course and natural history of SFA. Seventy-four patients sensitized to sesame were evaluated using clinical records, questionnaires, skin prick tests (SPT), in vitro specific immunoglobulin (sIg) E, and oral challenges (OC) and categorized into three groups: group A: patients who experienced allergic reaction after ingestion of sesame-containing food (n = 45); group B: patients evaluated for atopic dermatitis and found to be sesame SPT-positive (n = 11); group C: patients with sensitization to sesame allergen (n = 18). Group A patients were followed for an average of 6.7 yr. Analysis of our results revealed that 76% of patients in group A developed the allergy by the age of 2. The median age at onset of allergy in these patients was 1 yr. Immediate reaction to a minimal amount of sesame was characteristic. Skin was the most common site of involvement, followed by respiratory and gastrointestinal systems. Tolerance developed in only 20% of the patients. High sIgE (>0.15 IU) was demonstrated only in 75% of those in which it was examined. Sixteen patients performed oral sesame food challenge which was found positive in 88%. No correlation was found between the size of SPT and the level of in vitro sesame IgE antibodies, the outcome of OC results, and the development of tolerance to sesame. In conclusion, SFA tends to appear early in life, but unlike cow's milk and egg allergy, persists in 80% of the cases. Typical reactions combined with positive sesame SPT are reliable for diagnosis.