Specific immunoglobulin E antibodies to peanut over time in relation to peanut intake, symptoms and age

The clinical outcome of peanut allergy and some factors associated with development of peanut allergy remain unsolved. It has not been clarified to what extent peanut intake affects immunoglobulin (IgE) antibody formation in peanut sensitized individuals. The aim of the study was to investigate the development of peanut hypersensitivity in children and adolescents with specific IgE antibodies to peanut, using questionnaires and current serum tests and comparing it to information obtained 5-6 yr earlier, to investigate how peanut intake during this period related to subject age, IgE antibody levels and symptoms and to investigate what information this patient group was given at the time of diagnosis regarding avoidance of peanut related food. All patients with detectable peanut-specific IgE antibodies investigated during 1994-1996 deriving from two allergy laboratories in the western region of Sweden were traced and reinvestigated (n=132). A total of 111 subjects (63 with peanut allergy and 48 peanut sensitized) participated in the questionnaire. Eighty-six of them consented to be enrolled in a further interview and renewed testing of specific IgE antibody to peanut 5 yr later. All tests were done using the Pharmacia CAP system. Increased IgE antibody levels during follow-up was related to age; subjects 0-6 yr at initial test occasion were more likely to have higher IgE antibody class than the older individuals (p=0.018). Exposure to peanut during the study, i.e. 5-6 yr since diagnosis, did not seem to affect the result. During the follow-up period, 29 out of 86 (34%) increased their IgE antibody class. At the second test occasion the remaining subjects had similar (28%) or lowered (38%) levels of IgE antibodies. Exposure to peanut during follow-up was more common in subjects with IgE antibody class 1-3 compared to subjects with high value (> 3) at the initial test (p=0.003). Reported symptoms during follow-up were also more common in subjects with initially high IgE antibody value. Individuals with initially high IgE antibodies to peanut had been given more information about peanut allergy and cross-reacting allergens than other individuals. The subjects over 6 yr of age showed a decrease in peanut-specific IgE class over a 5-yr period. Together with the literature, our result suggest that follow-up and renewed testing is recommended, since there may be a change in IgE antibody classes and clinical sensitivity over time. Even in Sweden, with a low consumption of peanuts, the youngest individuals with peanut sensitization experienced a similar course of events that has been reported in other countries.     

Feeding a soy formula to children with cow's milk allergy: the development of immunoglobulin E-mediated allergy to soy and peanuts.

Peanut allergy has been associated with the intake of soy milk or a soy formula. We studied the development of immunoglobulin E antibodies specific to soy and peanuts and of allergic reactions caused by peanuts, in children with confirmed cow's milk (CM) allergy fed either a soy formula or an extensively hydrolyzed formula (EHF). One hundred and seventy infants with documented CM allergy (CMA) were randomly assigned to receive either a soy formula or an EHF. The children were followed to the age of 4 yr. Peanut-specific immunoglobulin E was measured at the age of 4. A detailed history of the occurrence of allergic reactions caused by peanuts was recorded by the parents. Soy-specific immunoglobulin E antibodies were measured at the time of diagnosis and at the ages of 1, 2 and 4 yr. Immunoglobulin E antibodies to soy (> or =0.35 kU/l) were found in 22 of 70 children fed the soy formula, and in 14 of 70 of the children fed the EHF (p = 0.082). In an open challenge with soy at the age of 4, no immediate reactions were observed. One of 72 children from the soy group had a delayed reaction. immunoglobulin E antibodies to peanuts (> or =0.35 kU/l) were found in 21 of 70 children fed the soy formula and 17 of 69 infants fed the EHF (p = 0.717). The incidence of reported peanut allergy in the soy group was two of 72 (3%) and four of 76 (5%) in the EHF group (p = 0.68). Development of immunoglobulin E-associated allergy to soy and peanuts was rare in our study group of milk allergic children. The use of a soy formula during the first 2 yr of life did not increase the risk of development of peanut-specific immunoglobulin E antibodies or of clinical peanut allergy.     

Skin prick testing predicts peanut challenge outcome in previously allergic or sensitized children with low serum peanut-specific IgE antibody concentration

Peanut allergy is transient in some children but it is not clear whether quantitating peanut-specific IgE by Skin Prick Test (SPT) adds additional information to fluorescent-enzyme immunoassay (FEIA) in discriminating between allergic and tolerant children. To investigate whether SPT with a commercial extract or fresh foods adds additional predictive information for peanut challenge in children with a low FEIA (<10 k UA/L) who were previously sensitized, or allergic to peanuts. Children from a hospital-based allergy service who were previously sensitized or allergic to peanuts were invited to undergo a peanut challenge unless they had a serum peanut-specific IgE>10 k UA/L, a previous severe reaction, or a recent reaction to peanuts (within two years). SPT with a commercial extract, raw and roasted saline soaked peanuts was performed immediately prior to open challenge in hospital with increasing quantity of peanuts until total of 26.7 g of peanut was consumed. A positive challenge consisted of an objective IgE mediated reaction occurring during the observation period. 54 children (median age of 6.3 years) were admitted for a challenge. Nineteen challenges were positive, 27 negative, five were indeterminate and three did not proceed after SPT. Commercial and fresh food extracts provided similar diagnostic information. A wheal diameter of >or=7 mm of the commercial extract predicted an allergic outcome with specificity 97%, positive predictive value 93% and sensitivity 83%. There was a tendency for an increase in SPT wheal since initial diagnosis in children who remained allergic to peanuts while it decreased in those with a negative challenge. The outcome of a peanut challenge in peanut sensitized or previously allergic children with a low FEIA can be predicted by SPT. In this cohort, not challenging children with a SPT wheal of >or=7 mm would have avoided 15 of 18 positive challenges and denied a challenge to one out of 27 tolerant children.     

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.     

Patterns of food hypersensitivity during sixteen years of double-blind, placebo-controlled food challenges

For 16 years the double-blind, placebo-controlled food challenge (DBPCFC) has been used at the National Jewish Center for Immunology and Respiratory Medicine to determine whether adverse reactions to foods do occur in children. The objective of these studies was to explore these reproducible adverse reactions and to characterize them. Although skin testing was performed on all subjects, a history of an adverse reaction to food and to subsequent DBPCFC were the only criteria for entry into this study. Of 480 children studied, 185 (39%) have had positive DBPCFC results. In these 480 children, 245 (24%) of 1014 DBPCFCs showed positive results. Egg, peanut, and cow milk accounted for 73% of the positive DBPCFC reactions, but many foods produced reactions. Skin test results were positive in most children with a positive DBPCFC reaction, but the large number of patients with asymptomatic hypersensitivity limited the accuracy of a positive skin test result alone as a predictor of clinical symptoms during food ingestion. Evaluation of results in this large number of children for a prolonged period revealed reproducible patterns of symptoms, timing, and incriminated foods. Placebo reactions were rare. The procedure was safe. Twelve youngsters with a negative DBPCFC result subsequently had positive reactions to open challenges when large amounts of the challenge food were used. In each of these cases the reactions were limited to areas of direct contact with the food or could be explained by the larger amount of food ingested during the open challenge. Multiple food hypersensitivity has been a rare finding. The DBPCFC should be the "gold standard" for both research and clinical diagnostic evaluations until it is superseded by methods that have yet to be developed.     

Exposure to peanuts in utero and in infancy and the development of sensitization to peanut allergens in young children

This study attempted to determine the underlying factors that may influence the development of peanut sensitization in young children in South Africa. One of our objectives was to ascertain whether the consumption of peanuts or peanut‐containing foods during pregnancy and lactation by mothers from atopic families impacted upon the development of an allergic response to peanuts in the child. Forty‐three children between the ages of 0 and 3 yr participated in this study. There were 25 peanut‐sensitized subjects and 18 control subjects (children sensitized to milk and/or egg, but not to peanuts). A significant association was found between peanut sensitization and sensitivity to soya (p=0.0002), wheat (p=0.03), and cod fish. We found that mothers who consumed peanuts more than once a week during pregnancy were more likely to have a peanut‐allergic child than mothers who consumed peanuts less than once a week (odds ratio=3.97, 98% confidence interval 0.73–24). Peanuts or peanut butter was introduced into the child's diet from a significantly younger age in the peanut‐allergic subjects (p<0.03). There was a positive correlation in the peanut‐allergic subjects between age of introduction of peanuts and age at the onset of symptoms ( r  = 0.63). Exclusive breast feeding did not protect against the development of peanut sensitization. Peanut allergy is associated with an increased risk of sensitization to other foods. It is more likely to occur if mothers eat peanuts more frequently during pregnancy and introduce it early to the infant's diet. These features highlight potentially avoidable factors that might prevent sensitization.     

Measurement of Ara h 1-, 2-, and 3-specific IgE antibodies is useful in diagnosis of peanut allergy in Japanese children

To cite this article: Ebisawa M, Movérare R, Sato S, Maruyama N, Borres MP, Komata T. Measurement of Ara h 1-, 2-, and 3-specific IgE antibodies is useful in diagnosis of peanut allergy in Japanese children. Pediatr Allergy Immunol 2012: 23: 573-581. ABSTRACT: Background: Food challenges are time-consuming, expensive, and not always possible to perform. Therefore, new tools to diagnose food allergy are desired. The aim was to evaluate IgE antibodies to peanut allergens in the diagnosis of peanut allergy in Japanese children using ImmunoCAP(?) and IgE immunoblotting. Methods: The study included 2-13-yr-old consecutive patients (n?=?57) referred to our specialist clinic for investigation of current peanut allergy using food challenge. All children had a previous doctor's diagnosis of peanut allergy and were on elimination diet. Serum samples were analyzed for IgE reactivity to peanut, recombinant (r) Ara h 1, 2, 3, 5, 8, and 9. IgE immunoblotting (n?=?23) was performed using extracts from raw and roasted peanut. Results: Twenty-six of the children failed (allergic group), and 31 passed the peanut challenge (tolerant group). The rAra h 2 ImmunoCAP test was superior in its ability to differentiate between children in the allergic and tolerant groups with a sensitivity and specificity of 88% and 84%, respectively (cutoff, 0.35?kU(A) /l). The combination of rAra h 1, 2, and 3 resulted in a higher specificity (94%) when IgE to all of them was the criteria for positivity. ImmunoCAP generally showed a good agreement with immunoblotting using both raw and roasted peanut for IgE reactivity to Ara h 1, 2, and 3. Conclusions: Measurement of IgE antibodies to rAra h 1, 2, and 3 is useful in the diagnosis of peanut allergy and in the investigation of reactions to raw and roasted peanut.     

General paediatricians and the case of resolving peanut allergy

Children with peanut allergy are almost always advised to avoid nuts for life. There have been recent reports from academic centres that in some cases the allergy might resolve and thus these dietary restrictions can be lifted. To evaluate resolution of peanut allergy in a selected group of children in a general paediatric setting. Children 4-16 yr old with a clear history of an allergic reaction to peanuts who had not had any reaction in the previous 2 yr were eligible. Specific immunoglobulin E (IgE) or skin prick test (SPT) at the time of diagnosis was sought. A SPT and specific IgE was then done and if this was 相似文献   

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.     

Lupine inhalation induced asthma in a child

The ingestion of lupine seed flour has been reported as a cause of allergic reactions. There is some evidence of its allergenic potential after inhalation. An 8-year-old asthmatic child, who was allergic to peanut, was studied in our clinic with the suspicion of an adverse drug reaction due to salbutamol. He suffered an asthma attack while playing with his brother, who had been eating lupine seed as snack; surprisingly, the asthma attack worsened with salbutamol. The skin tests showed a positive result with Lupinus albus extract, peanut, garbanzo bean, navy bean, pea, green bean, lentil, soy, Olea europea pollen, grass pollen and Plantago lanceolata pollen. The prick-by-prick tests both from dried seeds and those preserved in salt and water were strongly positive. Serum specific IgE antibodies were positive to Lupine albus (1.43 kU/l), peanut (4.32 kU/l), soy (2.15 kU/l), lentil (3.12 kU/l) and garbanzo (0.7 kU/l). After informed consent salbutamol was well tolerated but the patient had asthma in 5 min of manipulation of the lupine seeds. In our case, reactivity with other legumes was also demonstrated, but only peanut allergy was relevant because boiled legumes were tolerated. It is also notorious that anamnesis is so important to assess the true etiological agents of asthma.     

Food hypersensitivity and atopic dermatitis: evaluation of 113 patients

One hundred thirteen patients with severe atopic dermatitis were evaluated for food hypersensitivity with double-blind placebo-controlled oral food challenges. Sixty-three (56%) children experienced 101 positive food challenges; skin symptoms developed in 85 (84%) challenges, gastrointestinal symptoms in 53 (52%), and respiratory symptoms in 32 (32%). Egg, peanut, and milk accounted for 72% of the hypersensitivity reactions induced. History and laboratory data were of marginal value in predicting which patients were likely to have food allergy. When patients were given appropriate restrictive diets based on oral food challenge results, approximately 40% of the 40 patients re-evaluated lost their hypersensitivity after 1 or 2 years, and most showed significant improvement in their clinical course compared with patients in whom no food allergy was documented. These studies demonstrate that food hypersensitivity plays a pathogenic role in some children with atopic dermatitis and that appropriate diagnosis and exclusionary diets can lead to significant improvement in their skin symptoms.     

Lessons from the clinical course of IgE-mediated cow milk allergy in Israel

Cow milk and milk products are the most common food products consumed in Israel; rates of allergy to cow milk exceed those of peanuts in infants and children. The aim of the present study was to evaluate retrospectively the clinical features and natural course of immunoglobulin (Ig) E-mediated cow milk allergy (CMA) in Israel. Data of children diagnosed with CMA from 1995 to 2003, were collected regarding age at first and most recent reactions, symptoms and signs, family history of atopy, other allergic diseases, emergency department visits, hospitalizations, and treatment. Patients with transient CMA were compared to those with persistent CMA (> or =3 yr old). The study group consisted of 105 patients, 43 with transient CMA (age range: 0.48-11 yr). The remaining 62 patients (age range: 3-16.5 yr) did not achieve tolerance to cow milk during the follow-up period. No differences were found between the groups in mean age and symptoms and signs at the first allergic reaction and family history of atopy. Patients with persistent CMA had a higher rate of asthma than patients with transient CMA (61.2% vs. 18.6%, p < 0.001). Fifty patients with persistent CMA had 137 subsequent allergic reactions after diagnosis, 25% of the reactions were due to oral milk challenge at the clinic and 75% due to accidental exposure, of which 13% required an emergency department visit and 8%, hospitalization. Only 19% of the reactions were treated with epinephrine injection. In conclusion, in our experience, less than half of the children diagnosed with IgE-mediated CMA during 9 yr, outgrew it. The patients with persistent CMA have a higher prevalence of asthma compared with the general population or to children with transient CMA. The high number of recurrent allergic reactions due to accidental exposure and the low rate of epinephrine usage in these patients point to a need for better education of patients and their families.     

Allergic reactions to measles (rubeola) vaccine in patients hypersensitive to egg protein

We evaluated two children with allergy to egg-white protein (ovalbumin) who had generalized urticaria, angioedema, and respiratory difficulty after immunization with live rubeola vaccine. In both patients, serum IgE reactive with ovalbumin-related antigens in the vaccine was demonstrated. Subsequent evaluation of 24 children with ovalbumin allergy revealed that those who had positive ovalbumin skin tests, but no clinical reaction to egg white, were skin test negative on prick and intradermal testing with measles vaccine and were safely immunized. They had no detectable IgE directed against the rubeola vaccine, although IgE directed at ovalbumin was present. Six patients who had severe allergic hypersensitivity reactions on exposure to ovalbumin had IgE antimeasles vaccine antibody and had positive reactions after intracutaneous or intradermal testing with the vaccine. These patients were safely immunized with increasing volumes (0.05 ml increments every 20 minutes) of measles vaccine to receive the full dose. These studies suggest that children with severe allergic hypersensitivity to egg white should be screened with an intracutaneous test prior to immunization with measles vaccine; however, children who have positive skin tests but no clinical reaction to ovalbumin exposure are at minimal risk for hypersensitivity reactions to measles immunization, as previously reported.     

Adverse reactions to milk in infants

AIM: To study the age when symptoms of adverse reactions to milk occur, in premature and term children, the debut of various symptoms, immunoglobulin E (IgE)- and non-IgE-mediated reactions and the frequency of tolerance at 1 year. METHODS: Six hundred and eight children, 193 premature and 416 term infants, were followed. Symptomatic children were invited to a clinical examination. The criteria for the diagnosis were: histories of suspected cow's milk allergy (CMA) and proven IgE-mediated reactions to cow's milk or positive elimination/challenge tests. RESULTS: Twenty-seven out of 555 (4.9%) were diagnosed with adverse reactions to cow's milk. All had symptoms before 6 months of age. The main symptoms were: pain behaviour (13), gastrointestinal symptoms (7), respiratory symptoms, (6) and atopic dermatitis (1). One child had proven IgE to cow's milk. Premature and term infants displayed the same symptoms and age of debut. Thirteen children were tolerant to cow's milk at 1 year. CONCLUSION: Adverse reactions to milk start early in life, with pain behaviour, gastrointestinal, and respiratory symptoms being the most common, and rarely atopic dermatitis. Non-IgE-mediated reactions were the most frequent. Symptoms and age of debut were the same in premature and term infants. Half of the children tolerated cow's milk at age 1.     

Sesame allergy in Britain: A questionnaire survey of members of the Anaphylaxis Campaign

Sesame is a major allergen in countries where it is a common food. It was noted that an increasing number of members of the UK charity, the anaphylaxis campaign, were reporting allergy to sesame. This study, sought to examine features of sesame allergy among members of the Anaphylaxis Campaign (which supports those at potentially life-threatening risk from allergies) focusing on clinical symptoms and features of the foods implicated. A physician-designed questionnaire was sent by post to 400 members of the Anaphylaxis Campaign who reported avoidance of sesame. Two hundred and eighty replies were received (70%). Twenty-three replies (7%) were excluded and 96 replies (24%) came from subjects who avoided sesame but had never reacted to it. One hundred and fifty people (54%) reported 288 reactions to sesame. 89% of reactive subjects reported other atopic diseases and notably 84% were also nut/peanut allergic. One in six (17%) had suffered potentially life-threatening symptoms, with 65% of severe reactions happening on first known exposure. The age of first reaction ranged from 6 months to 65 yr. The majority of reactions reported (91%) involved foods or dishes which had sesame as a deliberate ingredient, rather than sesame as an accidental contaminant. Respondents represented a well-informed and highly selected group of people at risk from potentially life-threatening allergies. Sesame should be identified clearly as an ingredient and separately from nuts and peanuts when it may be an allergen contaminant. People at potential risk need clear allergy diagnosis and informed guidance to enable them to avoid this key allergen more easily.     

Parental satisfaction with oral peanut food challenges; perception of outcomes and impact on management of peanut allergy

Nguyen M, Wainstein BK, Hu W, Ziegler JB. Parental satisfaction with oral peanut food challenges; perception of outcomes and impact on management of peanut allergy.
Pediatr Allergy Immunol 2010: 21: 1119–1126.
© 2010 John Wiley & Sons A/S Oral peanut food challenges (OPFC) are the ‘gold standard’ for diagnosing peanut allergy in children. However, there are few data on parental perception of such challenges. We aimed to investigate the parental experience of and satisfaction with OPFC and reported dietary management of children with a history of peanut allergy following OPFC. Telephone interviews were conducted with parents of children who had undergone an open‐label OPFC at a specialist paediatric allergy centre. Forty‐six of 76 eligible parents participated. Of those parents, 54% were very satisfied with the OPFC. The highest levels of satisfaction were reported in relation to (i) clarification of the severity of the child’s peanut allergy (ii) the support provided by staff and (iii) determining the child was tolerant of peanut or assessed to be at low risk of anaphylaxis from accidental peanut exposure. When the outcome of the challenge was perceived to be equivocal, levels of parental satisfaction were lower. Other areas of dissatisfaction included difficulties inducing peanut ingestion, parental distress at seeing their child unwell and perception of inadequate follow‐up. Ninety‐four per cent of parents could not remember the amount of peanut ingested, and 24% could not remember whether management advice was given after the OPFC or reported that none was given. Reported compliance with recalled advice to avoid peanut was found in all cases but one, whilst recalled advice to reintroduce peanuts following a negative challenge was followed in 5/9 cases. Although 12 parents reported that their child had an allergic reaction caused by accidental exposure to peanut since the OPFC, only four were certain peanut was the cause. Comprehensive education, counselling and follow‐up subsequent to an OPFC are required. Parents of children whose challenge outcome is inconclusive should be targeted for support.     

Establishing the diagnosis of peanut allergy in children never exposed to peanut or with an uncertain history: a cross‐Canada study

Ben‐Shoshan M, Kagan R, Primeau M‐N, Alizadehfar R, Turnbull E, Harada L, Dufresne C, Allen M, Joseph L, St. Pierre Y, Clarke A. Establishing the diagnosis of peanut allergy in children never exposed to peanut or with an uncertain history: a cross‐Canada study.
Pediatr Allergy Immunol 2010: 21: 920–926.
© 2010 John Wiley & Sons A/S The diagnosis of peanut allergy (PA) can be complex especially in children never exposed to peanut or with an uncertain history. The aim of the study is to determine which diagnostic algorithms are used by Canadian allergists in such children. Children 1–17 yrs old never exposed to peanut or with an uncertain history having an allergist‐confirmed diagnosis of PA were recruited from the Montreal Children’s Hospital (MCH) and allergy advocacy organizations. Data on their clinical history and confirmatory testing were compared to six diagnostic algorithms: I. Skin prick test (SPT) ≥8 mm or specific IgE ≥5 kU/l or positive food challenge (+FC); II. SPT ≥8 or IgE ≥15 or +FC; III. SPT ≥13 or IgE ≥5 or +FC; IV. SPT ≥13 or IgE ≥15 or +FC; V. SPT ≥3 and IgE ≥5 or IgE ≥5 or +FC; VI. SPT ≥3 and IgE ≥15 or IgE ≥15 or +FC. Multivariate logistic regression analysis was used to identify factors associated with the use of each algorithm. Of 497 children recruited, 70% provided full data. The least stringent algorithm, algorithm I, was applied in 81.6% (95% CI, 77–85.6%) of children and the most stringent, algorithm VI, in 42.6% (95% CI, 37.2–48.1%).The factor most associated with the use of all algorithms was diagnosis made at the MCH in those never exposed to peanut. Other factors associated with the use of specific diagnostic algorithms were higher paternal education, longer disease duration, and the presence of hives, asthma, eczema, or other food allergies. Over 18% (95% CI, 14.4–23.0%) of children were diagnosed with PA without fulfilling even the least stringent diagnostic criteria.     

DOG HYPERSENSITIVITY IN ASTHMATIC CHILDREN

ABSTRACT. The occurrence of dog hypersensitivity in 203 unselected asthmatic children was investigated by means of the skin prick test, the provocation test and RAST. The history of past and present exposure to dogs, symptoms in contact with dogs, and the effects of pet avoidance were examined. The amount of dog dander antigens was analyzed by counter-immunoelectrophoresis from dust samples from 67 homes. A history of past or present dog hypersensitivity was obtained from 120 subjects (59%). A positive (≧++) prick test reaction was observed in 113 (56%), a positive provocation test result in 84 (41%) and a RAST class ≧ 1 in 140 (69%). The serum levels of IgE antibodies to dog dander correlated significantly with serum total IgE and the frequency of asthmatic attacks. The occurrence of dog allergy was not significantly associated with past or present exposure to dogs at home. However, the children who were exposed to dogs during the first year of life had dog allergy more often than those with late or without exposure. Significant amounts of dog dander antigen were also found in dust samples from homes where dogs have never been kept. Serum samples from previous years were available from 24 patients. Rising or steadily high levels of IgE antibodies to dog dander were observed even in subjects who strictly avoided dogs. The results show that dog hypersensitivity is an important cause of allergic disorders in asthmatic children, and that the common presence of dog dander antigens in our environment may induce dog allergy even without direct exposure to dogs.     

Reference values for IgE concentration in serum of children. Method: ImmunoCAP-FEIA system]

Age specific IgE reference values were determined in serum of 224 children by the aid of the ImmunoCAP fluorescence enzyme immunoassay method. Results: Cord blood: less than 0.35 kU/l; Till 0.5 year: less than 2.0 kU/l; 0.5-2 years: up to 3.8 kU/l; 2-5 years: up to 16.0 kU/l; 5-8 years: up to 26.2 kU/l; 8-12 years: up to 34.6 kU/l; 12-16 years: up to 26.3 kU/l. These IgE reference values can be used for the diagnosis of pathological elevated IgE concentrations in serum of children.     

Natural history of egg hypersensitivity.

Twenty-five children with clinical egg hypersensitivity, confirmed by double-blind challenge, were followed for between 2 and 2 1/2 years. Clinical egg hypersensitivity was fund to have resolved in 11 children but was persistent in 14. Skin prick tests reactions to egg were initially of equivalent size in the resolved and persistent groups, but became negative or diminished in size with resolution of clinical egg hypersensitivity, while remaining positive in the group with persisting symptoms. Symptoms after egg ingestion were categorised as cutaneous, gastrointestinal, respiratory, and angioedema. The adverse reactions of the resolved group were either cutaneous or gastrointestinal symptoms. The persisting group had multisystem involvement and most of them developed angioedema and respiratory symptoms. These differences may be useful as prognostic indicators in clinical egg hypersensitivity.