***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND The double-blind , placebo-controlled food challenge ( DBPCFC ) is the " gold st and ard " for diagnosis of food hypersensitivity . Skin prick tests and RASTs are sensitive indicators of food-specific IgE antibodies but poor predictors of clinical reactivity . Previous studies suggested that high concentrations of food-specific IgE antibody were predictive of food-induced clinical symptoms . Because the CAP System FEIA ( Pharmacia Diagnostics , Uppsala , Sweden ) provides a quantitative assessment of allergen-specific IgE antibody , this study was undertaken to determine the potential utility of the CAP System FEIA in diagnosis of IgE-mediated food hypersensitivity . METHODS Sera from 196 patients with food allergy were analyzed for specific IgE antibodies to egg , milk , peanut , soy , wheat , and fish by CAP System FEIA .  Sera were r and omly selected from 300 stored sample s of children and adolescents who had been evaluated by history , skin prick tests , and DBPCFCs . The study population was highly atopic ; all patients had atopic dermatitis , and approximately 50 % had asthma and allergic rhinitis at the time of initial evaluation . The performance characteristics of the CAP System FEIA were compared with those of skin prick tests and the outcome of DBPCFCs or " convincing " histories of anaphylactic reactions . RESULTS The prevalence of specific food allergies in the study population varied from 22 % for wheat to 73 % for egg . Allergy to egg , milk , peanut , and soy accounted for 87 % of confirmed reactions . The performance characteristics of skin prick tests and CAP System FEIA ( egg , milk , peanut , fish ) were comparable , with excellent sensitivity and negative predictive accuracy but poor specificity and positive predictive accuracy . The performance characteristics of the CAP System FEIA for soy and wheat were poor . For egg , milk , peanut , and fish allergy , diagnostic levels of IgE , which could predict clinical reactivity in this population with greater than 95 % certainty , were identified : egg , 6 kilounits of allergen-specific IgE per liter ( kU[A]/L ) ; milk , 32 kU(A)/L ; peanut , 15 kU(A)/L ; and fish , 20 kU(A)/L. CONCLUSIONS When compared with the outcome of DBPCFCs , results of CAP System FEIA are generally comparable to those of skin prick tests in predicting symptomatic food hypersensitivity . Furthermore , by measuring the concentrations of food-specific IgE antibodies with the CAP System FEIA , it is possible to identify a subset of patients who are highly likely ( > 95 % ) to experience clinical reactions to egg , milk , peanut , or fish . This could eliminate the need to perform DBPCFCs in a significant number of patients suspected of having IgE-mediated food allergy BACKGROUND Little is known about the cause of food-induced anaphylaxis in children or about the factors that might affect its clinical severity . OBJECTIVE The aim of this study was to investigate the cause of food-induced anaphylaxis in children in Italy and to identify factors that could influence the appearance of symptoms and the severity of anaphylaxis . METHODS One hundred and sixty-three children with anaphylaxis consecutively attending 29 outpatient allergy clinics throughout Italy were enrolled in this prospect i ve study . Information about past anaphylaxis episodes was collected with a st and ardized question naire . Food sensitization was evaluated by skin-prick test . RESULTS A clinical history of asthma increased the risk of wheezing [ odds ratio ( OR ) 2.2 ; 95 % confidence interval ( CI ) 1.1 - 4.5 ] and respiratory arrest ( OR 6.9 ; 95 % CI 1.4 - 34.2 ) . A clinical history of chronic/relapsing gastrointestinal symptoms increased the risk of vomiting ( OR 2.1 ; 95 % CI 0.9 - 4.3 ) , hypotension ( OR 7.9 ; 95 % CI 1.9 - 32.0 ) , and bradycardia/cardiac arrest ( OR 9.2 ; 95 % CI 0.9 - 91.3 ) . The severity of present and previous episodes was similar only in patients with mild or moderate anaphylaxis . Peanut and egg were the most frequent causes of severe anaphylaxis . CONCLUSIONS A clinical history of asthma and chronic/relapsing gastrointestinal symptoms ( probably linked to food allergy ) may predict the development of respiratory and gastrointestinal symptoms and the severity of anaphylaxis Background : The objective of the present study was to evaluate the relevance of skin tests and the concentration of cow 's milk‐specific IgE antibodies in correlation with oral cow 's milk challenge in infants with suspected cow 's milk allergy Five children aged 12‐40 months with IgE‐mediated adverse reactions to cow milk ( immediate onset clinical pattern of cow milk allergy ) were orally challenged double‐blind in r and om order with three different milk preparations processed from the same batch of milk 1 ) raw untreated cow milk , 2 ) pasteurized cow milk , 3 ) homogenized and pasteurized cow milk , and 4 ) Nutramigen ® (a commercial hypoallergenic infant formula based on hydrolysed casein ) as placebo .  Skin prick tests with the same preparations were also performed . On oral challenge the three different processed milk types provoked significant and similar allergic reactions in each child , and no adverse reactions followed the challenge with placebo ( Nutramigen ) . Skin prick test with the same milk products were positive in all children and comparable to the results with an extract of purified raw cow milk protein ( Soluprickreg ; ) , whereas Nutramigen did not elicit any skin reactions . A tendency towards a lower threshold of reaction and larger skin reactions induced by the processed milk preparations might indicate an increased ability of pasteurized and homogenized/pasteurized milk to evoke allergic reactions in patients allergic to milk BACKGROUND A milk-free diet with substitute formula should be established when immediate symptomatic hypersensitivity to cows ' milk protein ( CMP ) is diagnosed , and therefore an accurate diagnosis is very important . OBJECTIVE This study aims to find the optimal cutoff values for specific IgE antibody levels that discriminate between allergic and tolerant infants by using cows ' milk and its principal proteins as allergens . METHODS A prospect i ve study was carried out on 170 patients under 1 year old ( mean , 4.8 months ) . These patients were seen consecutively over a 4-year period in our outpatient clinic and for the first time because of a reaction suggesting immediate hypersensitivity after ingestion of cows ' milk formula . A clinical history , prick test with cows ' milk and its proteins ( alpha-lact-albumin , beta-lactoglobulin , and casein ) , determination of specific IgE antibodies with the CAP system FEIA for the same allergens as for the prick test , and a challenge test according to the diagnostic protocol were performed in all of the children . A study of validity of the prick test ( cutoff point , 3 mm ) and CAP system by using different cutoff points in the specific IgE values for cows ' milk and its proteins were also analyzed . RESULTS Prevalence of immediate symptomatic hypersensitivity to CMP in this study was 44 % . When both the whole milk and its principal milk proteins were used in the prick test , the negative predictive value was very high , and a negative value excluded allergy in 97 % of the patients . When the different cutoff points of the specific IgE for milk were analyzed , 2.5 KU(A)/L had a positive predictive value of 90 % and 5 KU(A)/L had a positive predictive value of 95 % . CONCLUSIONS When diagnosing immediate hypersensitivity to CMP in infants , negative skin test responses exclude allergy in most of the patients . If the prick test response is positive , specific IgE levels for cows ' milk may be helpful . If these values are 2.5 KU(A)/L or greater , the challenge test should not be performed because of its high positive predictive value ( 90 % ) Skin Prick Test ( SPT 's ) are performed to identify the causes of allergy . However , low diagnostic accuracy is a limitation to SPT , for which many possible causes have been suggested . The protein composition and allergenicity of crude allergen extracts from foods and commercial allergen extracts for SPT were analyzed . Clinical significance s of SPT using crude allergen extracts from foods were compared with those using commercial allergen extracts .  A total of 292 atopic dermatitis patients were involved in this study . Crude allergen extracts were prepared from milk , egg white , egg yolk , and soybean . The protein composition of food allergen extracts and commercial allergen extracts of milk , whole egg , white , egg yolk , and soybean were compared by SDS-PAGE . The allergenicity was tested by the immunoblotting method using immune sera . SPTs were performed using crude and commercial allergen . Double-blind placebo- controlled food challenge ( DBPCFC ) was performed to verify the SPT results and to compare the clinical significance of crude and commercial allergen extracts . Protein composition differed markedly between crude and commercial allergen extracts . By immunoblotting , crude and commercial allergen extracts showed different allergenicity . The SPT results using crude and commercial allergen extracts showed significant differences . The prevalence of milk , egg and soybean allergy was over 35 % in atopic dermatitis . The accuracy of SPT using crude allergen extracts from foods was significantly higher than that using commercial allergen extracts . In the case of soybeans , the result of SPT using commercial allergen extract was clinical ly insignificant for the prediction of soybean allergy . The source of allergen extract was very important for the appropriate SPT in food allergy . The accuracy of SPT might be improved using the appropriate allergen source for food allergy We evaluated the value of the patch test , skin prick test , and milk‐specific IgE by CAP RAST in 301 infants with suspected hypersensitivity to cow 's milk . The patch test was carried out with milk powder , and the skin prick test with cow 's milk‐based formula . Hypersensitivity to cow 's milk was determined with double‐blind , placebo‐controlled challenge . An immediate reaction to cow 's milk challenge was observed in 100 infants ( 33 % ) , a delayed reaction in 76 ( 25 % ) , and a negative result in 125 ( 42 % ) . Skin prick test wheals were significantly greater in infants with immediate reactions than in infants with delayed or negative reactions . Milk‐specific IgE was correlated with the skin prick test ( r=0.78 , P<0.001 , n=268 ) but did not contribute to further discrimination of immediate reactions from delayed or negative reactions compared to skin prick test alone . In our study population , the skin prick test ( diameter ≥3 mm ) showed a specificity and sensitivity of 91 % and 69 % ; the results for milk‐specific IgE ( ≥0.7 kU/l ) were 88 % and 58 % , respectively . The patch test did not distinguish subjects with immediate or delayed reactions from those with negative reactions BACKGROUND The double-blind , placebo-controlled food challenge is considered the gold st and ard for diagnosing food allergy . However , in a retrospective analysis of children and adolescents with atopic dermatitis and food allergy , discrete food-specific IgE concentrations were established that could predict clinical reactivity to egg , milk , peanut , and fish with greater than 95 % certainty . OBJECTIVE The purpose of this investigation was to determine the utility of these 95 % predictive decision points in a prospect i ve evaluation of food allergy . METHODS Sera from 100 consecutive children and adolescents referred for evaluation of food allergy were analyzed for specific IgE antibodies to egg , milk , peanut , soy , wheat , and fish by using the Pharmacia CAP System FEIA . Food-specific IgE values were compared with history and the results of skin prick tests and food challenges to determine the efficacy of previously established 95 % predictive decision points in identifying patients with increased probability of reacting during a specific food challenge . RESULTS One hundred children ( 62 % male ; median age , 3.8 years ; range , 0.4 - 14.3 years ) were evaluated for food allergy . The diagnosis of food allergy was established by means of history or oral food challenge . On the basis of the previously established 95 % predictive decision points for egg , milk , peanut , and fish allergy , greater than 95 % of food allergies diagnosed in this prospect i ve study were correctly identified by quantifying serum food-specific IgE concentrations . CONCLUSION In a prospect i ve study of children and adolescents referred for evaluation of food allergy , previously established 95 % predictive decision points of food-specific IgE antibody concentrations for 4 major food allergens were effective in predicting clinical reactivity . Quantification of food-specific IgE is a useful test for diagnosing symptomatic allergy to egg , milk , peanut , and fish in the pediatric population and could eliminate the need to perform double-blind , placebo-controlled food challenges in a significant number of children 
    Output:
    
Any cut-offs are proposed for single cow ’s milk proteins and for baked milk allergy in children younger than 2 years .
In Children ≥ 2 years of age it is hard to define practical cut-offs for allergy to fresh and baked cow ’s milk .
Conclusions None of the cut-offs proposed in the literature can be used to definitely confirm cow ’s milk allergy diagnosis , either to fresh pasteurized or to baked milk .