allergy
[Prediction of food allergy by using cord blood IgE levels]

[Article in Chinese]

Li F, Li HQ, Wang RH.

Department of Child Health Care, Children's Hospital Affiliated to Chongqing Medical University, Chongqing, 400014 China.

OBJECTIVE: As more attention is paid to food allergy which is already regarded as a public health problem, there is still a lot of uncertainty as to the mechanisms and there are limited therapeutic methods for this problem. It is of importance to screen the susceptible infants as early as possible. The present study was conducted to learn whether cord blood IgE levels (CBIgE) could be used as a predictor of food allergy, and to find out factors which influence the predictive accuracy of CBIgE. METHODS: The present study enrolled 118 infants born between April 2001and July 2001, and the authors followed up the infants until they were 4 months old. At the end of follow up, 105 infants had complete data for evaluation. Paper radioimmunosorbent tests (PRIST) were used for CBIgE assay, and parents were required to answer the standard questionnaires and the food skin prick tests (SPT) were taken for all infants. RESULTS: At the end of follow-up, the infants were divided into 3 groups based on food allergy status: FA group with obvious food allergy, SFA group with suspected food allergy and NFA group without allergy. The median values of CBIgE levels in FA group were higher than those in SFA and NFA groups (4.80 IU/L, 0.55 IU/L, 0.87 IU/L, P < 0.01). When the cutoff value for CBIgE was set at 0.9 IU/L (CBIgE(0.9)), 42.9% of infants were found to have food allergy in the higher CBIgE group, 6.7% in the lower CBIgE group (P < 0.01, RR 95% CI = 2.715 approximately 15.221); when the cutoff value was set at 0.5 IU/L (CBIgE(0.5)), 30.9% in the higher CBIgE group and 5.00% in the lower CBIgE group (P < 0.01, RR 95% CI = 1.954 approximately 19.552). In addition, the sensitivity of CBIgE(0.9).as a predictor of food allergy, was 78.95% and the specificity, efficiency and odd product were 73.68%, 74.74%, and 10.50, generally better than CBIgE(0.5) of which the sensitivity, specificity, efficiency, odd product were 89.47%, 5.00%, 57.89%, 8.5 (P < 0.01). With the multi-factor stepwise regression analysis, our study indicated that exposure to cigarette smoke (OR 95%CI = 4.3340 approximately 71.2432), animal fur (OR 95% CI = 1.9869 approximately 30.7472), and egg supplement (OR 95% CI = 1.9340 approximately 25.8885) before 4 months of age might be the risk factors which may result in the predictive uncertainty of CBIgE. CONCLUSIONS: Increased CBIgE levels might be the risk factor which result in food allergy; CBIgE(0.9), as a predictor of food allergy, is superior to CBIgE(0.5). However, some environmental factors, such as early exposure to cigarette smoke, animal fur and too early egg supplement would lead to predictive uncertainty of CBIgE.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=15059487&dopt=Abstract allergy medicine



allergy
IgE and IgG binding epitopes on alpha-lactalbumin and beta-lactoglobulin in cow's milk allergy.

Jarvinen KM, Chatchatee P, Bardina L, Beyer K, Sampson HA.

Division of Pediatric Allergy and Immunology and Jaffe Institute for Food Allergy, The Mount Sinai School of Medicine, New York, NY 10029-6574, USA.

BACKGROUND: Cow's milk is one of the most common causes of food allergy in the first years of life. We recently defined IgE and IgG binding epitopes for alpha(s1)-casein, a major cow's milk allergen, and found an association between recognition of certain epitopes and clinical symptoms of cow's milk allergy (CMA). Since alpha-lactalbumin (ALA) and beta-lactoglobulin (BLG) are suspected to be significant allergens in cow's milk, we sought to determine the structure of sequential epitopes recognized by IgE antibodies to these proteins. We further sought to assess the pattern of epitope recognition in association with the clinical outcome of CMA. METHODS: According to the known amino acid sequence of ALA and BLG, 57 and 77 overlapping decapeptides (offset by two amino acids), respectively, were synthesized on a cellulose derivatized membrane. Sera from 11 patients 4-18 years of age with persistent CMA (IgE to cow's milk >100 kU(A)/l) were used to identify IgE binding epitopes. In addition, 8 patients < 3 years of age and likely to outgrow their milk allergy (IgE to cow's milk < 30 kU(A)/l) were used to investigate the differences in epitope recognition between patients with 'persistent' and those with 'transient' CMA. Seven patients 4-18 years of age were used for assessing the IgG binding regions. RESULTS: In patients with persistent allergy, four IgE binding and three IgG binding regions were identified on ALA, and seven IgE and six IgG binding epitopes were detected on BLG. The younger patients that are likely to outgrow their allergy recognized only three of these IgE binding epitopes on BLG and none on ALA. CONCLUSIONS: The presence of IgE antibodies to multiple linear allergenic epitopes may be a marker of persistent CMA. The usefulness of IgE binding to distinct epitopes on whey proteins in defining the patients that would have a lifelong CMA needs to be investigated in further studies. Copyright 2001 S. Karger AG, Basel

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11729348&dopt=Abstract allergy medicine



allergy
Role of conformational and linear epitopes in the achievement of tolerance in cow's milk allergy.

Vila L, Beyer K, Jarvinen KM, Chatchatee P, Bardina L, Sampson HA.

Division of Paediatric Allergy and Immunology, The Mount Sinai Medical Center, New York, NY 10029-6574, USA.

BACKGROUND: Cow's milk (CM) is one of the leading causes of food allergy in children. However, approximately 85% of milk-allergic children become clinically tolerant to CM within the first 3 years of life. The mechanisms involved in the achievement of tolerance remain unknown. OBJECTIVE: To study whether IgE antibodies from children with persistent cow's milk allergy (CMA) differ from children who become clinically tolerant in their ability to recognize linear and conformational epitopes of alpha(s1)- and beta-casein. METHODS: Thirty-six milk-allergic children were included in the study: 11 of the children became clinically tolerant, and 25 had persistent CMA. Blood was obtained from all patients during the time they showed clinical reactions to milk challenge. Six non-milk-allergic children served as controls. Specific IgE antibodies against linear (denatured) as well as conformational (native) milk proteins were determined by probing dot-blots with patients' sera. In addition, selected decapeptides from alpha(s1)- and beta-casein, previously found to be suggestive of persistent CMA, were synthesized on a cellulose-derivatized membrane and probed with individual sera from 10 patients who outgrew CMA and from 10 patients with persistent CMA. RESULTS: Analysis of immunodot-blots showed that, in comparison to tolerant patients, milk-allergic children with persistent symptoms had a significantly higher ratio of specific IgE antibodies to linearized than to native alpha- and beta-casein (P < 0.005 and P < 0.02, respectively). Comparing the selected decapeptides, six of the 10 patients with persistent allergy recognized the peptide corresponding to amino acids 69-78 from alpha(s1)-casein while none of the patients who outgrew CMA had IgE binding to this epitope. CONCLUSION: Patients with persistent milk allergy possess higher detectable levels of IgE antibodies to linear epitopes from alpha(s1)- and beta-casein than children who have achieved tolerance. Specific IgE binding to particular linear epitopes in alpha(s1)-casein may be a predictive factor for persistence of CMA.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11678861&dopt=Abstract allergy medicine



allergy
Springtime pollinosis and oral allergy syndrome in Sapporo.

Gotoda H, Maguchi S, Kawahara H, Terayama Y, Fukuda S.

Department of Otorhinolaryngology, Teine Keijinkai Hospital, Sapporo, Japan. bys14155 nifty.ne.jp

OBJECTIVE: The purpose of this present study was to investigate pollinosis in the spring and oral allergy syndrome (OAS) in Sapporo to utilize it for future treatment. MATERIALS AND METHODS: Of the patients referred to our out-patient clinic during April and May in 1999. all those that were suspected to have pollinosis were asked to fill in a questionnaire. A 101 patients (30 males and 71 females) with a mean age of 33 years (range 7-74 years) answered the questionnaire. In all, the patients specific IgE tests were performed. RESULTS: The most common allergen was birch, affecting 54 of 87 patients (62%). In 61% of patients with birch allergy, we observed fruit and vegetable allergy. Among them, apple was the most prevalent allergen (97%), followed by peach (67%), cherry (58%), pear (40%), plum (40%) and melon (33%). The sensitivity of skin prick test with commercial extract to apple was low (11%). CONCLUSION: Patients with birch pollen allergy had OAS much more frequently than ever reported in Japan, although OAS has not widely been known in Japan. Patients with birch pollen allergy should be informed about the possibility of hypersensitivity to certain fruits.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11683343&dopt=Abstract allergy medicine



allergy
Influence of occupational exposure to latex on the prevalence of sensitization and allergy to latex in a Swiss hospital.

Galobardes B, Quiliquini AM, Roux N, Taramarcaz P, Schira JC, Bernstein M, Morabia A, Hauser C.

Division of Clinical Epidemiology, Division of Allergy and Immunology, University Hospital, Geneva, Switzerland.

BACKGROUND: Replacement of powdered latex gloves has been recommended in order to prevent the development of latex allergy in health care workers. The conclusion that occupational exposure to latex gloves represents a risk factor for latex allergy is mainly based on studies without exposure controls. Atopy is also thought to be a risk factor for the development of latex allergy. OBJECTIVE: To determine the prevalence of atopy, sensitization to latex, and symptoms following latex exposure in professionally exposed and nonexposed hospital personnel by means of a cross-sectional study. METHODS: Six hundred randomly sampled individuals working in medicine and surgery departments and in surgery theaters and 300 sex- and age-matched individuals classified as administrative personnel were selected from the employee data base of the Geneva University Hospital. A questionnaire about exposure to latex and symptoms following this exposure was sent to all individuals. Skin prick test reactions and serum IgE to latex as well as standard environmental allergens were determined in both groups. RESULTS: Respiratory and skin (local) symptoms but not objective tests of latex sensitization (positive skin prick test and specific IgE to latex) were significantly associated with occupational exposure to latex (p < 0.001). Only among atopics subjects was 15 years or more of occupational exposure associated with a significantly higher prevalence of local symptoms than among those who were exposed from 1 to 9 years (odds ratio: 3.2; 95% confidence interval: 1.6-6.5). Atopy was significantly associated with sensitization to latex (odds ratio: 10.3; 95% confidence interval: 4.0-26.6) but not with local symptoms. Tests of latex sensitization were both frequently positive, less frequently negative, resulting in low kappa values. CONCLUSION: These results support the current preventive health care recommendation to replace powdered latex gloves. In atopics, increasing years of occupational exposure increase the risk of developing latex allergy. In contrast to questionnaires about local symptoms, skin prick tests and specific serum IgE to latex are of limited value in epidemiologic studies of latex allergy. Copyright 2001 S. Karger AG, Basel

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11701976&dopt=Abstract allergy medicine



allergy
Association between nasal allergy and a coding variant of the Fc epsilon RI beta gene Glu237Gly in a Japanese population.

Nagata H, Mutoh H, Kumahara K, Arimoto Y, Tomemori T, Sakurai D, Arase K, Ohno K, Yamakoshi T, Nakano K, Okawa T, Numata T, Konno A.

Department of Otorhinolaryngology, Chiba University School of Medicine, 1-8-1 Inohana, Chuoh-ku, Chiba 260-8670, Japan. nagatah ho.chiba-u.ac.jp

The gene for the beta-chain of the high-affinity receptor for IgE (Fc epsilon RI beta) has been proposed as a candidate gene for atopy. A coding variant Glu237Gly has been studied in various populations with asthma and atopy, and the results were controversial for association of the variant with atopy/asthma. Because nasal allergy is a more common atopic disease and shows less remission than asthma, we analyzed whether the Glu237Gly variant is correlated with nasal allergy. The study enrolled 233 patients with nasal allergy and 100 control subjects. Further, three subgroups were selected: patients with perennial nasal allergy (n=149), Japanese cedar pollinosis (n=189), and allergy to multiple allergens (n=45). The allele frequency of Gly237 in the controls and patients was 0.14 and 0.20, and the frequency of Gly237-positive subjects was 0.23 and 0.356, respectively. There was a significant association between Gly237-positivity and nasal allergy, perennial nasal allergy, Japanese cedar pollinosis, and allergy to multiple allergens. Among all 333 subjects we observed a significant relationship between Gly237 and elevated levels of serum total IgE (>250 IU/ml) and very high IgE (>1000 IU/ml). Among patients positive for a specific IgE, Gly237 was significantly associated with high IgE for house dust, mite, and Japanese cedar pollen. These results suggest that the Glu237Gly variant of the Fc epsilon RI beta gene is involved in the development of nasal allergy through the process for the production of both specific and nonspecific IgE antibodies.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11702205&dopt=Abstract allergy medicine



allergy
Validity of specific IgE antibodies in children with egg allergy.

Boyano Martinez T, Garcia-Ara C, Diaz-Pena JM, Munoz FM, Garcia Sanchez G, Esteban MM.

Servicio de Alergia Infantil, Hospital Universitario La Paz, Madrid, Spain.

BACKGROUND: The demonstration of specific IgE antibodies to egg supports the existence of allergy to this food, but a correct diagnosis can only be obtained after a challenge test. Several studies have assessed different cut-off points in the level of these antibodies as predictors of clinical reactivity. OBJECTIVE: Validation of the specific IgE antibodies measured by the CAP System Fluorescence enzyme immunoassay (FEIA) technique in the diagnosis of egg allergy in children under 2 years of age. METHODS: A prospective study of 81 children with suspected egg allergy was performed. Specific IgE antibodies was quantified for egg white, egg yolk, ovoalbumin and ovomucoid. The diagnostic challenge test was carried out following the previously established criteria. The validity of the specific IgE antibodies was analysed using children with a negative diagnostic challenge test as control group. RESULTS: The prevalence of egg allergy in the group studied was 79% and egg white was the allergen that showed the greatest diagnostic efficacy. The sensitivity and positive predictive value of the prick test and of the CAP to egg white were excellent and the specificity and the negative predictive value had lower values. A level of > or = 0.35 KU(A)/L for specific IgE antibodies to egg white predicted the existence of reaction in 94% of the cases. CONCLUSIONS: Quantification of the specific IgE antibodies to egg white is useful in the diagnosis of egg allergy. In children under 2 years of age with a background of immediate hypersensitivity after egg ingestion and presence of specific IgE antibodies to egg white of > or = 0.35 KU(A)/L, diagnostic challenge test is not necessary to establish the diagnosis of allergy to this food.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11591198&dopt=Abstract allergy medicine