Successful oral tolerance induction to cow’s milk in a child with allergy to extensively hydrolysed formula

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Epidemiología de la alergia alimentaria en la edad pediátria / Epidemiology of food allergy in children

La incidencia de alergia alimentaria (AA) en niños es del 2-8%. Más del 90% de las AA en los lactantes son causados por leche de vaca (LV), huevo de gallina, soya, maní, nueces, trigo, pescado y mariscos. Existen algunos factores de riesgo para el desarrollo de AA. El impacto de la LM sobre el desarrollo de las alergias es controversial. Hay un 0.21% de APLV neonatal. La introducción antes del 4 mes de vida de más de 4 alimentos está asociada con un mayor riesgo de dermatitis atópica. La prueba de provocación oral a los alimentos es una herramienta valiosa en el diagnóstico inicial y el manejo de las reacciones adversas a los alimentos. Los síntomas sugestivos de APLV pueden ser encontrados en cerca del 5-15% de los niños. La hipersensibilidad mediada por IgE a la proteína de la LV, es predominantemente una enfermedad del período del lactante.

The incidence of food allergy (FA) in children of 2-8%. Over 90% of FA in infants are caused by cow's milk (CM), chicken egg, soy, peanuts, tree nuts, wheat, fish and seafood. There are some risk factors for the development of FA. The impact of breastfeeding on the development of allergies is controversial. There is a 0.21% of neonatal CMPA. The introduction before 4 months of life of more than 4 foods is associated with an increased risk of atopic dermatitis. The oral challenge test to food is a valuable tool in the initial diagnosis and management of adverse reactions to food. Symptoms suggestive of CMPA can be found in about 5-15% of children. The IgE-mediated hypersensitivity to the protein in the CM, is predominantly a disease of the infant period.

New guidelines for managing cow's milk allergy in infants.

The prevalence of allergic disease has increased markedly over the last 50 years. Food allergy usually manifests in early childhood as part of the so-called atopic march and most commonly includes one or more of the following foods: cow's milk, hen's egg, soy, peanuts and tree nuts, wheat, sesame seed, kiwi fruit and seafood. In the UK about 2% of infants develop cow's milk protein allergy (CMPA), but as many as 15% of infants present with symptoms suggestive of an adverse reaction to cow's milk protein. The diagnosis of CMPA is based on one or more of the following: a detailed clinical history, allergy test results (skin prick testing [SPT] and/or specific immunoglobulin E [IgE]) and, if required, supervised incremental milk challenges. The majority of UK primary care centres do not have access to these tests and may also be unfamiliar with the interpretation or results. In addition, they do not have the facilities for supervised food challenges. Empirical treatment is often required pending confirmation of allergy or referral to a specialist centre, but requires clear guidelines. No consensus guidelines currently exist for the diagnosis and management of CMPA in the UK. An international task force has recently published proposed guidelines for the management of CMPA. These provide separate algorithms covering the diagnosis and management of CMPA for both breast-fed and formula-fed infants and discuss the use of hypoallergenic formulae, elimination diets and diagnostic tests. Revisions and adaptations for the UK market are required and are discussed in this article.

Cow's milk allergy in adults is rare but severe: both casein and whey proteins are involved.

BACKGROUND: Studies on cow's milk allergy (CMA) in adults are scarce. Little is known about the clinical symptoms, eliciting doses (ED), and allergens involved. OBJECTIVE: The aim of this study was to analyse the clinical symptoms, ED and allergen recognition in adult CMA patients, compared with cow's milk (CM)-sensitized, but tolerant controls. METHODS: Adult CMA patients were evaluated by standardized questionnaires (n=30), skin prick tests (SPTs) and specific IgE for CM allergens (n=18), and a double-blind placebo-controlled food challenge (DBPCFC, n=10). A control group (n=25) of CM-sensitized, but tolerant adults was included. RESULTS: The majority of CMA patients (20/30, 67%) reported severe symptoms. In all patients participating in DBPCFC, CMA was confirmed. ED for subjective symptoms (0.3-300 mg CM protein) were significantly lower than that for objective symptoms (300-9000 mg CM protein). The severity of CMA by history and ED was not correlated with SPT or IgE. Patients had higher SPT reactivity than controls for CM, alpha-lactalbumin and beta-lactoglobulin (P=0.002, P=0.014 and P=0.004) but not for casein. Specific IgE to CM tended to be higher (P=0.068) and IgE to casein was higher in patients than that in controls (P=0.016). No difference was observed for IgE to alpha-lactalbumin and beta-lactoglobulin. CONCLUSION: Adult CMA is severe in nature. ED are low, starting from 0.3 mg CM protein. Patients with CMA recognize the same major allergens (casein and whey proteins) as controls, but display a stronger SPT and IgE reactivity.

The prevalence of CMA/CMPI in young children: the validity of parentally perceived reactions in a population-based study.

BACKGROUND: The present study aimed to estimate the prevalence of adverse reactions to milk, as population-based prevalence estimates based on objective diagnostic procedures are rare. METHODS: Children with parentally reported reactions to milk were selected for further examination from a population-based cohort of 2721 children. At the age of 2(1/2) years, they underwent a stepwise diagnostic procedure that included diet trials at home, skin prick tests, and open and double-blind, placebo-controlled food challenges. A sample of children with symptoms not attributed to milk was selected for assessment of unrecognized reactions. RESULTS: The estimated point prevalence of cow's milk allergy and cow's milk protein intolerance (CMA/CMPI) in children with parentally perceived reactions at the age of 2(1/2) years was estimated to be 1.1% (CI 0.8-1.6). However, this was an underestimate, as unrecognized reactions were detected. Most reactions were not IgE-mediated. The positive predictive value of a parentally perceived reaction depended on the number of times it had been reported and was good for reactions reported three times (at 12, 18, and 24 months of age). CONCLUSION: The present study confirms previous findings that parents overestimate milk as a cause of symptoms in their children; however, it also indicates that unrecognized reactions may be a problem as well.

The natural history of cow's milk protein allergy/intolerance.

In prospective studies th incidence of cow's milk protein allergy and intolerance (CMPA/CMPI) in infancy in western industrialized countries has been estimated to be about 2-3% based on strict diagnostic criteria. A significant association between early neonatal exposure to cow's milk formula feeding and subsequent development of CMPA/CMPI has been documented. The small amounts of 'foreign' protein in human milk may rather induce tolerance than allergic sensitization. The findings of specific IgE to individual cow's milk proteins in cord blood of the majority of infants who later develop CMPA/CMPI suggests a prenatal sensitization may play a role in the pathogenesis of CMPA/CMPI. Perhaps a weak intrauterine education of low IgE-response may need to 'boosted' neonatally in order to cause clinical disease. The prognosis of CMPA/CMPI is good with a recovery of about 45-56% at one year, 60-77% at two years and 71-87% at three years. Associated adverse reactions to other foods, especially egg, soy, peanut and citrus develop in about 41-54%. Allergy to potential environmental inhalant allergens has been reported in up to 28% by three years and up to 80% before the age of puberty. Especially, infants with an early increased IgE response to cow's milk protein have an increased risk of persisting CMPA, development of persistent adverse reactions to other foods and development of allergy against environmental inhalant allergens. Cow's milk protein/intolerance (CMPA/CMPI), meaning reproducible adverse reactions to cow's milk protein(s) may be due to the interaction between one or more milk proteins and one or more immune mechanisms, possible any of the four basic types of hypersensitivity reactions. Immunologically mediated reactions are defined as CMPA. Mostly, CMPA is caused by IgE-mediated (type I) reactions, but evidence for type III (immune complex) reactions and type IV (cell mediated reactions) have been demonstrated as reviewed by Høst (1994) and Ortolani & Vighi (1995). Non immunologically reactions against cow's milk protein(s) are defined as CMPI. However, it should be stressed that many studies on 'cow's milk allergy' have not investigated the immunological basis of the clinical reactions. In most instances of cow's milk protein hypersensitivity only diagnostic investigations such as skin prick test and RAST indicative of IgE-mediated reactions are performed. In fact, CMPA cannot be ruled out unless extensive diagnostic tests for type II-III-IV reactions have proved negative. Thus, the classification of adverse reactions to cow's milk proteins depends on the extent and the quality of performed diagnostic tests for immune mediated reactions. At present, no single laboratory test is diagnostic of CMPA/CMPI, and differentiation between CMPA and CMPI cannot be based solely on clinical symptoms. Therefore the diagnosis has to be based on strict well-defined elimination and milk challenge procedure (Hill & Hosking, 1991), (Høst, 1994). Preferably, double-blind placebo-controlled challenges (DBPCFC) should be carried out in children older than 1-2 years of age. In infants open controlled challenges have been shown to be reliable when performed under professional observation in a hospital setting (Høst & Halken, 1990).

[Milk feeding of infants and cow's milk protein hypersensitivity]. / Alimentation lactée du nourrisson et allergie aux protéines du lait de vache.

BACKGROUND: Cow milk protein intolerance (CMPI) is characterized by a wide range of symptoms and signs affecting the gastro-intestinal tract, the respiratory system and the skin. A better definition, a stricter application of diagnostic criteria and critical evaluation of certain immunologic correlates can contribute to a better understanding and preventive treatment of this entity. POPULATION AND METHODS: Two hundred-seventeen infants with CMPI seen between January 1980 and December 1993 were included in the study. They were classified into two groups: 1) acute reaginic CMPI (type I): 125 infants and 2) CMP enteropathy or colitis (type III or IV): 92 infants, according to classical diagnostic criteria. Careful investigation concerning the type of milk feeding (breast or artificial) proposed prior to clinical manifestations was performed. RESULTS: Among the 125 infants (aged 3 to 20 weeks) with acute reaginic CMPI, 121 (97%) had been breast-fed with a sudden weaning; 30 of these infants had also received one to three formula bottles during the first 3 days of life and 14 certainly had not received such formula bottles. Among the 92 infants with CMPI, type III or IV, 33 (38%) had been exclusively breast-fed, a figure quite similar to the breast feeding incidence in our region. CONCLUSIONS: These results clearly show the importance of breast-feeding in the personal history of CMPI. Acute reaginic type of CMPI is favored by early ingestion of formula bottles in breast-fed infants and by early sudden weaning. Hypoallergenic formula in five cases was unable to protect infants against further allergic manifestation.

[Allergy to cow's milk proteins: the sensitivity of specific and nonspecific laboratory tests]. / Allergia alle proteine del latte vaccino: sensibilità dei tests di laboratorio specifici ed aspecifici.

Authors report their experience of a population of 308 children affected by cow's milk allergy who presented gastrointestinal, respiratory and cutaneous symptoms. Diagnosis was based on challenge with cow's milk proteins and on laboratory specific tests (RAST, prick test) and non specific ones (PRIST, eosinophil count, 1-h xylose test, occult blood in the stools), following ESPGAN criteria. The patients were subdivided in 3 groups: a) patients with prevalent gastrointestinal symptoms; b) patients with prevalent cutaneous symptoms and c) patients with both, gastrointestinal and cutaneous symptoms. The sensitivity of the employed tests was evaluated either in the whole patient population or in the there group according to symptoms. Our data show a high sensitivity of the RAST for cow's milk (70%) versus a lower sensitivity of prick test (53%) when the whole patients population was considered. Moreover statistically important differences of the sensitivity of the various tests were found when the three groups of patients were considered, as well as when such a comparison was done in patients subdivided according to age (more or less than 6 months). Finally the concord between RAST and prick test was evaluated in the three groups.