Hypoallergenicity of an extensively hydrolyzed whey formula

Several different protein hydrolysate-based infant formulas have been promoted as hypoallergenic and considered suitable for the dietary management of cow's milk allergy (CMA). Accepting that none of the hydrolysate-based products is completely safe, the American Academy of Pediatrics (AAP) recommends that these formulas should be tested in a double-blind placebo-controlled setting and tolerated by at least 90% of children with proven CMA. In principle, this recommendation is also endorsed by the European Society of Paediatric Gastroenterology and Nutrition (ESPGAN) and the European Society of Paediatric Allergy and Clinical Immunology (ESPACI). In this two-center study, 32 children with proven CMA were tested with the extensive hydrolysate whey formula Nutrilon Pepti, for comparison with Profylac (extensive) and Nan HA (partial) whey hydrolysate products. Skin-prick tests (SPTs) were, respectively, positive to the three hydrolysate formulas in 19%, 15%, and 32% of children. After oral challenge it was concluded that 97% (95% CI: 85-100%) of the children tolerated Nutrilon Pepti, 94% (95% CI: 75-100%) tolerated Profylac, and 64% (95% CI: 37-81%) tolerated Nan HA. This study demonstrates that the extensive hydrolysates Nutrilon Pepti and Profylac are well tolerated in a population of children with proven CMA and that both products can be considered safe for their intended use. This study confirms that a very small number of children react even to extensively hydrolyzed formulas. SPT prior to oral exposure to the hydrolysate-based formulas can indicate whether a child is at risk of showing reactions to the product. Introduction of new products to these children should be carried out under a doctor's supervision. However, the majority of the SPT-positive children did tolerate the two extensively hydrolyzed whey-based formulas tested.

Absence of association between a variant of the mast cell chymase gene and atopic dermatitis in an Italian population

Atopic dermatitis (AD) is a chronic dermatitis which belongs to the group of atopy-related diseases together with asthma and rhinitis. IgE and mast cell chymase (MCC) play a key role in atopic or allergic inflammation of the skin. An association between AD and a genetic variant of the MCC has been reported in a Japanese population, but failure of confirmation has rendered this association questionable. We have tested for genetic association to an MCC variant in relation to AD in an Italian population. No significant association was found between AD and MCC genotypes. These data suggest that BstXI MCC polymorphism may not be involved in AD.

A major susceptibility locus for atopic dermatitis maps to chromosome 3q21

Atopic dermatitis (eczema) is a chronic inflammatory skin disease with onset mainly in early childhood It is commonly the initial clinical manifestation of allergic disease, often preceding the onset of respiratory allergies. Along with asthma and allergic rhinitis, atopic dermatitis is an important manifestation of atopy that is characterized by the formation of allergy antibodies (IgE) to environmental allergens. In the developed countries, the prevalence of atopic dermatitis is approximately 15%, with a steady increase over the past decades. Genetic and environmental factors interact to determine disease susceptibility and expression, and twin studies indicate that the genetic contribution is substantial. To identify susceptibility loci for atopic dermatitis, we ascertained 199 families with at least two affected siblings based on established diagnostic criteria. A genome-wide linkage study revealed highly significant evidence for linkage on chromosome 3q21 (Zall=4.31, P= 8.42 10(-6)). Moreover, this locus provided significant evidence for linkage of allergic sensitization under the assumption of paternal imprinting (hlod=3.71,alpha=44%), further supporting the presence of an atopy gene in this region. Our findings indicate that distinct genetic factors contribute to susceptibility to atopic dermatitis and that the study of this disease opens new avenues to dissect the genetics of atopy.

Allergenicity of mare's milk in children with cow's milk allergy

BACKGROUND

Cow's milk allergy is a common disease of infancy and early childhood. If the baby is not breast-fed, a substitute for cow's milk formula is necessary.

OBJECTIVE

The aim of this study was to investigate, in vitro and in vivo, the allergenicity of mare's milk in a population of selected children with severe IgE-mediated cow's milk allergy.

METHODS

Twenty-five children (17 male and 8 female) aged 19 to 72 months (median age 34 months) with IgE-mediated cow's milk allergy were selected for this study. All the children underwent skin prick tests with cow's milk and mare's milk and double-blind placebo-controlled oral food challenge (DBPCOFC) with fresh cow's milk, fresh mare's milk, and, as placebo, a soy formula (Isomil, Abbott, Campoverde, Italy). We performed immunoblotting of cow's and mare's milk developed with IgE from allergic children.

RESULTS

All the children showed strong positive skin test responses to cow's milk (4+); 2 children had positive skin test responses to mare's milk (2+). All children had positive DBPCOFCs to cow's milk; one child had a positive DBPCOFC to mare's milk. No children reacted to the placebo (Isomil). In the cow's milk, some proteins are able to strongly react with human IgE; when the sera are tested with mare's milk, the bands corresponding to the same proteins are recognized by a lower percentage of sera.

CONCLUSION

These data suggest that mare's milk can be regarded as a good substitute of cow's milk in most children with severe IgE-mediated cow's milk allergy. It would be prudent, however, to confirm its tolerability by a supervised titrated oral challenge test.

Prevention and management of food allergy

The phenotypic expression and natural history of food allergy vary widely according to the patient's age, disease presentation and type of offending food. Prevention of food allergy might be achieved by altering the dietary factors responsible for the sensitization and phenotypic expression of the disease. Owing to the peculiarity of the atopic status, a minute amount of allergens can trigger both sensitization and symptoms in atopic individuals. The oral dose of beta-lactoglobulin causing sensitization can be estimated to be between 1 ng and several milligrams. In food allergy, sensitization and treatment are allergen specific; therefore, for primary prevention (avoiding sensitization) and secondary prevention of food allergy (avoiding symptoms in an already sensitized subject), a product without immunogenic and allergenic epitopes should be given in each case. Babies of atopic parents are particularly prone to develop food allergy and for this reason they are called high-risk babies. Cow's milk is the most commonly offending food in both gastrointestinal and cutaneous manifestations. Cow's milk proteins are potent allergens and around 2.5% of infants experience cow's milk allergy in the first years of life. The major risk factors for cow's milk allergy are positive family history of atopy and early exposure to cow's milk proteins. Hydrolysate formulae have been developed for the purpose of reducing the allergenicity of cow's milk proteins. More recently, partially and extensively hydrolysed formulae have also been used for feeding babies with a high risk of atopy for the prevention of cow's milk allergy. However, according to the results of a recent randomized controlled study, only an extensively hydrolysated formula, and not a partially hydrolysated formula, significantly decreased the prevalence of cow's milk allergy.

Allergenicity of goat's milk in children with cow's milk allergy

BACKGROUND

Cow's milk allergy (CMA) is a common disease of infancy and childhood. An appropriate cow's milk (CM) substitute is necessary for feeding babies with CMA. CM substitutes are soy formulas and casein- or whey-based extensively hydrolyzed formulas. In several countries, including Italy, goat's milk (GM) formulas are available, and some physicians recommend them for feeding babies with CMA.

OBJECTIVE

We sought to investigate, in vitro and in vivo, the allergenicity of GM in 26 children with proven IgE-mediated CMA.

METHODS

All the children underwent skin tests with CM and GM; detection of specific serum IgE to CM and GM; and double-blind, placebo-controlled, oral food challenges (DBPCOFCs) with fresh CM, GM, and, as placebo, a soy formula (Isomil, Abbott, Italy). CAP inhibition and immunoblotting inhibition assays were also carried out in 1 of 26 and 4 of 26 children with positive RAST results to both CM and GM, respectively.

RESULTS

All the children had positive skin test responses and CAP results to both CM and GM, all had positive DBPCOFC results to CM, and 24 of 26 had positive DBPCOFCs to GM. In CAP inhibition tests, preincubation of serum with CM or GM strongly inhibited IgE either to CM or to GM. In immunoblotting inhibition assays, preincubation with CM completely extinguished reactivity to GM, whereas GM partially inhibited reactivity to CM.

CONCLUSIONS

These data strongly indicate that GM is not an appropriate CM substitute for children with IgE-mediated CMA. A warning on the lack of safety of GM for children with CMA should be on the label of GM formulas to prevent severe allergic reactions in babies with CMA.

Soy protein for the prevention and treatment of children with cow-milk allergy

Soy-protein formulas are widely used for feeding babies with cow-milk allergy. When they first were marketed, these formulas were the only available cow-milk substitute and they ensured a normal life for many children who were affected by the large spectrum of clinical manifestations of cow-milk allergy. Soy-protein formulas were also given to allergy-prone infants for the prevention of atopic diseases when breast milk was not available. Several researchers studied the prevalence of soy sensitization in allergic disease. Few studies used a challenge test for the diagnosis of soy allergy, even those in patients in whom soy allergy was suspected. In most studies the diagnosis of soy allergy was based on anecdotal case histories reported by parents and was not substantiated by scientific diagnostic criteria: no challenge test to soy was made nor were data available on specific immunoglobulin E to soy. In this paper we critically reviewed literature on the safety of feeding soy-protein formulas to babies with cow-milk allergy as well as on the prevention of cow-milk allergy.

Effectiveness of a home-made meat based formula (the Rezza-Cardi diet) as a diagnostic tool in children with food-induced atopic dermatitis

The aim of this study was to investigate the effectiveness of a home-made meat based formula (the Rezza-Cardi diet), as a diagnostic tool for children with atopic dermatitis and suspected multiple food hypersensitivity. Severity scores for atopic dermatitis, body weight and serum lipid profile were evaluated at baseline and four weeks following the feeding with the home-made meat based formula in 16 children with atopic dermatitis and suspected multiple food hypersensitivity. The severity score of the skin lesions improved considerably in all the children; no significant difference was observed in the serum lipid levels before and after one month following the feeding with the home-made meat based formula. All children gained weight according to the Italian Standards. The results of this study indicate that the home-made meat based formula is a useful elimination diet in children with atopic dermatitis and suspected multiple food hypersensitivity.

Soy allergy is not common in atopic children: a multicenter study

The aim of the present study was to evaluate the prevalence of soy allergy (positive skin test and positive challenge test) in a large cohort of atopic children, many of them soy fed early in life for several months. In order to investigate the prevalence of soy allergy, two groups of children were enrolled into the study. The first group comprised a cohort of 505 children with personal history suggestive of food allergy. The second group included 243 children born of atopic parents, who had been soy protein formula fed for the first six months of life for the prevention of cow's milk allergy and who had been prospectively followed up, from birth to 5 years. As regards the prevalence of soy allergy in the cohort of children suffering from allergic disease: 31/505 children (6%) had positive skin prick test to soy, however only six of the 31 children with positive skin prick test to soy had positive challenge test to soy. With regard to the prevalence of soy allergy in the children who had been soy protein formula fed in the first six months of life (second group): 14/243 children (6%) had positive skin prick test to soy, but the double blind placebo control oral food challenge to soy was positive in only one of these 14 children. In conclusion documented soy allergy is not common in atopic children.

[From atopic dermatitis to asthma]

Atopic dermatitis (AD) is the most common chronic skin disorder in infancy and childhood and is the main hallmark of atopic constitution. The disease is multifactorial, and although genetic predisposition is certainly a prerequisite, a number of environmental factors modulate the phenotypic expression of AD. The majority of affected children shows IgE sensitisation towards a large variety of foods and aeroallergens. Since at least 1600, it has been recognized that patients with AD have a high predisposition to develop asthma. Recent epidemiological studies show that AD is commonly seen in individuals from families with a history of asthma. In addition, in population where asthma is uncommon, AD is also uncommon. The sex distribution of AD and asthma is the same, with boys affected significantly more often by these two atopic diseases and in similar proportions. The ETAC project (Early Treatment of the Atopic Child) is a large multicenter, multi-national, double blind, placebo controlled, randomised trial. The main objective of the study is to stop the progression from AD to asthma in young children with AD using early therapeutic intervention with Cetirizine and the second objective is to investigate the main risk factors for the onset of asthma. The results of this study indicate that exposure to potent allergens such as cat or mite significantly increased the risk of sensitisation to these allergens. Prolonged breast feeding was associated with a lowest sensitisation rate to cow milk proteins and to egg. Therefore environmental factors seem to play a crucial role in IgE sensitisation in children with AD.

Effect of preseasonal enzyme potentiated desensitisation (EPD) on plasma-IL-6 and IL-10 of grass pollen-sensitive asthmatic children

EPD is a method of preventive immunotherapy which employs b-glucuronidase as a biological response modifier. Plasma IL-6 and IL-10 were measured before a single injection of EPD, 24 hours later and 15 days after in a group of 17 children suffering from grass pollen asthma. 17 normal untreated children were used as controls. Although the study was conducted before the grass pollen season when the allergic children were free of symptoms, their plasma IL-6 and IL-10 were significantly elevated before the injection of EPD. 24 hours after treatment the plasma IL-10 had increased significantly and there was also a slight rise in IL-6. 15 days after treatment IL-6 had fallen to normal but IL-10 was still elevated. These findings suggest antigen-specific and non-specific mechanisms by which EPD may produce clinical improvement.

Measles vaccine in egg allergic children: poor immunogenicity of the Edmoston-Zagreb strain

Despite the fact that a number of recent studies have shown that measles/ mumps/rubella vaccine is safe for egg allergic children, many pediatricians are still concerned about immunization in egg allergic children. In Europe, a measles vaccine with the Edmoston-Zagreb strain (EZMV) grown in human fibroblast culture has been developed and recommended for children with egg allergy. However, some doubt arises on the efficacy of this strain due to its weak immunogenicity. The aim of this study was to investigate the immunogenicity of the EZMV in comparison to the measles vaccine with the Schwarz strain (SWMV) grown in a chick embryo fibroblast culture. Thirty-nine children affected by severe immediate manifestations due to IgE mediated egg allergy were enrolled. The children received at random the SWMV (Morupar, Sclavo) or the EZMV (Triviraten, Berna) in one 0.5 ml subcutaneous injection, and were checked for any immediate allergic reactions in the following 4 hours. Blood samples were taken for the detection of specific antibody response 5 months after the immunization. In SWMV seroconverted children (18/19) the geometric mean antibody titer was 3 times higher than that observed in EZMV seroconverted children (17/20) (p < 0.01). No allergic reactions occurred following the immunization with the two different vaccines. This data confirms the safety of SWMV in egg allergic children. In addition, the present study provides further data on the lower immunogenicity of the EZMV in comparison to the SWMV.

[Food allergy: recent findings]

Food allergy induces in infancy and childhood a large variety of symptoms which may be trivial in many children, chronic and severe in others and even fatal in rare cases. According to double-blind placebo controlled oral food challenges, cow's milk, egg, wheat and fish are the most common offending foods. Elimination of the offending food(s) is imperative for the management of children with food allergy. An appropriate formula without cow's milk proteins and allergenic epitopes should be given to infants with cow's milk allergy. Breast feeding and selected weaning after the sixth month of life are recommended for the prevention of food allergy in atopic prone babies.

[Results of a multicentric study for the prevention of atopic allergy. 48 months of follow up]

With the cooperation of 12 Maternity Hospitals we have started a prospective study to evaluate the effect of dietary and environmental measures in the development of atopic disease in "at risk" newborns. The preventive measures included: exclusive breast feeding for the first 6 months of life, soy milk supplement when breast milk is not sufficient, elimination of house dust, no smoking in the house, etc. All infants were seen at the age of 1, 3, 6, 9, 12 months and twice-a-year afterwards. 1213 babies have been enrolled. At the last follow-up of 48 months 531 children are 4 year old. The cumulative prevalence of atopic disease was 20%: 11 (2%) children developed atopic dermatitis, 69 (13%) asthma, 21 (4%) rinithis, 5 (1%) urticaria. The low prevalence of atopic disease and the trivial course of the allergic manifestations in the children who followed the preventive measures (78/444 = 18%) and the higher (28/87 = 32%) in these who did not (p < 0.01) stressed the importance of such manipulations for the prevention of atopy in "at risk" babies.

Enzyme-potentiated desensitization in children with asthma and mite allergy: a double-blind study

The aim of this study was to evaluate the efficacy and safety of enzyme-potentiated desensitization (EPD) in children with asthma. Twenty asthmatic children (14 males and 6 females; median age: 8.5 years) were included in the study. They had positive skin tests to Dermatophagoides pteronyssinus (Dpt), no history of other allergy and had suffered from asthma for at least two years. The children were examined before starting the trial, at the first EPD dose, after 8 weeks, at the second EPD dose and 3 months after the second EPD dose. Blood samples for PRIST and RAST were drawn before the first and at the second EPD dose, and at the last follow-up. Conjunctival provocation tests (CPT) and skin test endpoint determinations were performed with dilutions of a freeze-dried Dpt extract (10-100,000 SQ-U/ml) at the start of the trial and at the last follow-up. Parents kept a diary record of the days with asthma and daily drug usage. The children were randomized to receive either two intradermal placebo injections or the active material with an 8-week interval (November 1991 and January 1992). Ten children received EPD and 10 children placebo. The intradermal injection of EPD (0.05 ml) contained 0.01 ml of beta-glucuronidase (40 Fishman units) and 0.04 ml of a mixture of inhalant allergens (1 Noon unit). The placebo injection consisted of buffer solution only. The EPD-treated children had significantly fewer days with asthma (p = 0.00000). In addition, the EPD-treated children used significantly less medication for the management of asthma attacks (p = 0.00000). At the start of the trial, three out of 10 children in the EPD group and two out of 10 in the placebo group reacted only to the highest dose of allergen used in the CPT (100,000 SQ/ml) (NS). At the last follow-up, the threshold dose in the CPT was 100,000 SQ/ml or more in nine out of 10 children in the EPD group and in four out of 10 children of the placebo group (p = 0.0349). At the last follow-up, one child in the EPD group had a negative CPT with all doses tested. Global clinical evaluation by the investigators showed that eight out of 10 EPD-treated children improved, in comparison with three out of 10 children in the placebo group (p = 0.0349). Assessment by the parents was six out of 10 and four out of 10 improved, respectively (NS). Specific IgE to Dpt, total IgE and skin prick test endpoints before and after EPD showed no significant changes. One child in the placebo group experienced mild urticaria several hours following the second injection. No other local or systemic side effects were reported. The results of the present study provide further data on the effectiveness and safety of EPD in patients with asthma.

Patch test response to house dust mites is positive in children with atopic dermatitis and in their parents

We studied the patch test response to Dermatophagoides pteronyssinus in 79 atopic children and in their parents. The atopic children were divided into 3 groups: 1) children with atopic dermatitis (group 1); 2) children who had suffered from atopic dermatitis but the disease was cured (group 2); and 3) atopic children with asthma and without atopic dermatitis (group 3). Our data show that a significantly higher proportion of children with atopic dermatitis (groups 1 and 2) have positive patch tests to Dermatophagoides pteronyssinus in comparison to atopic children without atopic dermatitis (group 3) and the controls (p < 0.001). In addition, we have shown that a positive patch test to Dermatophagoides pteronyssinus is significantly more common in parents of children with atopic dermatitis with respect to parents of children with asthma or parents of control children.

Evaluation of the efficacy of oral cromolyn sodium or an oligoantigenic diet in children with atopic dermatitis: a multicenter study of 1085 patients

One thousand eighty-five children with atopic dermatitis were enrolled in a multicenter study to evaluate the efficacy of 4 weeks of oral sodium cromoglycate or 4 weeks of a restricted diet. One thousand-eleven children (93%) concluded the study. At the end of the trial there was a significant improvement in skin lesions in the two groups: 61% of the patients in the sodium cromoglycate group and 69% in the restricted diet showed a significant improvement in atopic dermatitis. We concluded that, at least in our experimental design, both sodium cromoglycate and a restricted diet are equally effective in atopic dermatitis.

Detection of undegraded beta-lactoglobulins and evaluation of the molecular weight of peptides in hydrolysate cow's milk formulae

Hydrolysate formulae have been developed with the purpose of reducing the allergenicity of cow's milk proteins, thus providing a suitable formula for feeding babies with cow's milk allergy. More recently, hydrolysate formulae have also been used with babies at high risk of atopy in order to prevent cow's milk allergy. The aim of the present study was to investigate the presence of intact cow's milk proteins and the molecular weights of peptides in several batches of two extensively hydrolyzed formulae and two partially hydrolyzed formulae. The results show the presence of a significant amount of intact beta-lactoglobulin in one partially hydrolyzed formula and of peptides with high molecular weights (>16,900 D) in the two partially hydrolyzed formulae. In conclusion, the present study confirms that partially hydrolysed formulae contain a large proportion of peptides with high molecular weights: in addition, undegraded beta-lactoglobulin was detected in a partially hydrolyzed whey formula. These data strongly indicate that partially hydrolyzed formulae may be not only allergenic in an already sensitized individual, but also immunogenic in a predisposed baby.

Natural history of IgE antibodies in children at risk for atopy

BACKGROUND

The relationship between atopic diseases and high serum IgE levels has been emphasized since the mid-sixties, when IgE antibodies were discovered. A number of environmental factors, such as the type of feeding, passive smoking, viral infections, early mold, house dust mite and pet fur exposure modulate IgE synthesis and affect the development of atopic diseases.

OBJECTIVE

The aim of the present study was to investigate the natural history of total and specific IgE antibodies in babies at risk for atopy, enrolled in a prospective study for the prevention of atopic disease, and follow-up from birth to 4 years of age.

METHODS

One hundred seventy-four babies (90 boys and 84 girls) at risk for atopy were enrolled in this study. At the last follow-up the children had a median age of 52 months (range 43 to 74 months), dietary and environmental manipulations for the prevention of atopic diseases were recommended. All the infants were examined at the ages of 1, 3, 6, 9, and 12 months and twice each year subsequently when detailed histories were taken and signs and symptoms of atopic disease were sought. Total and specific IgE to cow milk, egg, soy, wheat, and Dermatophagoides pteronyssinus (Dpt) were measured at 6 and 12 months of life and then every year.

RESULTS

During the first 24 months of life, the number of children with specific IgE to foods (n = 30) was significantly higher in comparison to the number of children with specific IgE to Dpt (n = 12) (P = .0006). Cow milk and egg were the most common offending foods. The number of children with IgE to cow milk (n = 14) was significantly higher than that with IgE to soy (n = 9) (P = .0011). Total serum IgE levels were significantly higher in the group of children who developed atopic disease in comparison with the group that did not (P < .01).

CONCLUSION

Dietary and environmental measures may influence the IgE response in atopy-prone children, thus confirming the role of environmental factors in the modulation of the phenotypic expression of atopy.

[The primary and secondary prevention of allergic diseases in the child "at risk" for atopy: a review of the literature and the authors' personal experience]

The increasing prevalence of the atopic diseases in the industrialized countries is closely linked together the numerous efforts to attempt to prevent them. Several Authors have suggested environmental and/or dietetic measures in the "at risk" babies in the first months of life, more critical for the atopy development. The environmental measures are directed to the avoidance of the major inhalant allergens (house dust mite, pet allergens, cigarette smoking, etc.). The employment of the acaricides can be useful to this purpose. The dietetic measures include: prolonged and exclusive breast feeding in the first six months of life, delayed and gradual weaning, avoidance of the major food allergens (cow's milk proteins, egg, fish, etc.) for the breast-feeding mother, choice of an adequate cow's milk substitute when the breast-feeding is not sufficient. For long time soya milk has been employed. In the last decade partially or highly hydrolyzed formulae were introduced, but in some cases they can be more allergenic of cow's milk. In this paper we reviewed the various environmental and dietetic measures and the different prevention programs that the several Authors have adopted in "at risk" babies.

Systemic reactions to specific immunotherapy in children with respiratory allergy: a prospective study

The aim of this multi-centre prospective study was to evaluate the prevalence of systemic reactions to specific immunotherapy in children with allergic asthma and or rhinitis. One thousand and fifty-six children (653 boys and 403 girls), median age 8.5 years, were enrolled in this three-year prospective study. All the children were treated with injections of the following allergenic extracts: 689 of house dust mite, 291 of grass, 109 of Parietaria, 13 of Alternaria, 6 of Artemisia and 11 of Olea. Among 1056 treated children, 41 (3.7%) had systemic reactions: 40 children (3.7%) experienced mild symptoms such as asthma and/or urticaria, and only one shock (0.08%). A total of 47,247 injections were administered, and the rate of systemic reactions, according to the number of total injections was only 0.08%. According to the allergenic extract, systemic reactions occurred in 29/689 children (4.2%) treated with house dust mites extract (0.09% of the injections), in 9/291 children (3.1%) treated with grass extract (0.07% of the injections) and in 3/109 children (2.8%) treated with Parietaria extract (0.06% of the injections). The prevalence of systemic reactions was significantly higher (p < 0.0001) in the children treated with house dust mite extract in comparison with those treated with pollen extracts. All the systemic reactions appeared within 30 minutes following the administration of the extract and occurred in 37/41 cases (90.2%) with the same dose, previously tolerated. Most reactions were mild, and were readily controlled by immediate emergency treatment. There was no need for hospitalization.(ABSTRACT TRUNCATED AT 250 WORDS)

Food allergy and asthma

Food allergy (FA) is one of the causes of atopic dermatitis (AD), of acute urticaria, of reactions of the gastrointestinal tract, and of acute systemic anaphylaxis, but its role in asthma appears to be less clear. The prevalence and incidence of subjects with food-induced wheezing have not been well studied. In addition, the number of subjects with proven food-induced wheezing by double-blind, placebo-controlled oral food challenge (DBPCOFC) has been small. At the moment wheezing is considered unusual in food-hypersensitive subjects, and wheezing as the unique symptom of FA is rare. Furthermore, most cases of food-induced asthma have been observed in children. Food allergy may trigger allergic respiratory symptoms through two main routes: ingestion or inhalation. Children with asthma, who are allergic to foods, present some particular features such as AD and a related significantly elevated total serum IgE level. Alternatively, FA may occur in patients who are "high IgE responder" and more prone to become sensitive to many allergens, including foods. Therefore, children with asthma and a history of AD and/or elevated total serum IgE level should be carefully assessed for FA. We have shown that a significant proportion of children with IgE-mediated cow's milk allergy experienced asthma following DBPCOFC with cow's milk.

Cord blood mononuclear leukocytes of neonates at risk of atopy have a deficiency of arachidonic acid

Essential fatty acids and their delta-6-desaturated derivatives are major components of cellular membrane phospholipids, contributing to their stability and functions. They are also precursors of inflammation mediators such as prostaglandins and leukotrienes, and are involved in cellular immunoregulation. Recent studies have stressed the importance of essential fatty acids in various diseases. Patients with atopic dermatitis have altered essential fatty acids levels in plasma and a clinical improvement has been shown after oral administration of essential fatty acids. The aim of our study was to investigate the distribution of essential fatty acids in the membranes of cord blood mononuclear leukocytes of newborns at risk of atopy, and to correlate the levels of essential fatty acids at birth with total IgE values and with the onset of atopic disease. Newborns at risk of atopic disease have a significant reduction in arachidonic acid in the membranes of cord blood mononuclear leukocytes. Our data show a significant decrease in arachidonic acid in neonates at risk of atopy, suggesting that the abnormality of essential fatty acids is a primary phenomenon associated with atopic status.

Atopic sensitization in children of Somali immigrants in Italy

Children of immigrants are known to be at greater risk for developing allergic manifestations than the population in general. In this study we observed children of Somali origin living in Italy in order to find plausible explanations for the high risk of allergic disease in immigrants. Fifty-two children aged 0-14 years (mean = 6.7 years) were examined during the spring season. The mothers of the children were asked to fill in a questionnaire on symptoms and signs of atopic diseases and the family history of atopy. In addition, a physical examination and skin tests were performed. All families used mattresses, pillows and/or blankets made of wool, known to favor the growth of mites. In the majority of these children's families we found at least five people cohabitating in the same room. Skin prick tests were most frequently positive for Dermatophagoides pteronyssinus. Seventy-four percent (14/19) of those with symptoms were positive to D. pteronyssinus. Only 14% (2/14) of those positive to D. pteronyssinus were positive to Lolium perenne. Thirty-seven percent (19/52) had atopic symptoms and 15% (5/33) of those without symptoms were positive to D. pteronyssinus (p < 0.0001 compared to those with symptoms). Sensitization to food allergens occurred less frequently as compared to common inhalant allergens (p < 0.0001). A high prevalence of atopic diseases among children of Somali immigrants in Italy might be attributed to contact with the new environment and poor socioeconomic conditions that promote, for example, the growth of mites. However, further studies are needed to document these differences.

Immunogenicity of a so-called hypoallergenic formula in at-risk babies: two case reports

The clinical and immunologic findings of two breast-fed babies who experienced anaphylaxis after a feeding with a partially whey hydrolysate formula (PWHF) are reported. Sensitization to this formula seems to have occurred in the first days of life in the Maternity Hospital where the babies were fed the same formula. These two case reports suggest that PWHF may be immunogenic in the IgE system. This data is in agreement with previous studies which showed intact fragments of cow's milk (CM) proteins in PWHF.

Allergenicity of milk protein hydrolysate formulae in children with cow's milk allergy

Cow's milk protein hydrolysate formulae have been developed to lower or eliminate the allergenicity of cow's milk proteins, and to reduce the antigenic load and the risk of sensitization. Cross-reactivity between different hydrolysate formulae and cow's milk proteins has been demonstrated. We have studied 20 children (median age 31 months, range 15-76 months) with a history of IgE-mediated cow's milk allergy. All the children had immediate allergic respiratory and/or cutaneous and/or gastro-intestinal reactions to cow's milk ingestion. In addition, the children had positive prick skin tests and positive RAST to cow's milk. Prick skin test, RAST, and double-blind placebo controlled food challenges were performed with three different hydrolysate formulae: a casein hydrolysate formula and two whey formulae, one partially and one extensively hydrolyzed. All 20 children had immediate allergic reactions after the challenge test with cow's milk. Only 2/20 children had a positive challenge test with a casein hydrolysate formula (Alimentum): one developed asthma and one urticaria. Two of the 15 children challenged with an extensively hydrolysed whey formula (Profylac) developed perioral erythema. Nine out of 20 children had a positive challenge test with a partially hydrolysed whey formula (Nidina H.A.): four developed asthma, three urticaria and two lip oedema. All children had positive prick skin tests to cow's milk proteins (casein and/or lactalbumin); 9 to Nidina H.A.; 3 to Profylac, and 3 to Alimentum. Specific IgE antibodies to cow's milk were present in all children; in 13 to Nidina H.A., in 4 to Profylac, and in 3 to Alimentum.

Is prevention of food allergy worthwhile?

Several studies performed in high-risk babies have demonstrated a significant reduction in the prevalence and severity of atopic diseases with dietary and environmental manipulations. It has been demonstrated that prolonged breast-feeding and the avoidance of cow's milk, eggs and fish during the first three months of lactation significantly decrease both the prevalence and the severity of atopic disease up to the age of 5 years. We have shown a significant reduction in both the prevalence and the incidence of atopic dermatitis, food allergy and asthma in high-risk children followed up to the age of 5 years who received preventive dietary (prolonged breast-feeding, cow's milk- and egg-free diet to the nursing mothers, supplementation with a soya formula containing sucrose when breast milk was not available, delayed weaning) and environmental measures (no smoking and no pets in the house, measures for the elimination of mites, etc.). However, occasionally, breast-fed infants may experience allergic sensitization to food antigens ingested by the mother during lactation. The factors that determine which infants will develop sensitization to food antigens in breast milk are not fully understood. The genetic predisposition to IgE-mediated hypersensitivity reactions is certainly a prerequisite; however, properties of human milk, such as immune characteristics, may play a role in the phenotypic expression of sensitization. Our studies suggest that the abnormally low levels of the long-chain polyunsaturated derivatives found in infants at risk of atopy are unlikely to be corrected by breast-feeding and may explain the contradictory results from studies on the effectiveness of breast milk against the development of atopic dermatitis.

Breast milk from mothers of children with newly developed atopic eczema has low levels of long chain polyunsaturated fatty acids

BACKGROUND

Infants at risk of atopic dermatitis have lower than normal levels of long chain polyunsaturated fatty acids. These fatty acids are normally present in substantial quantities in human breast milk.

METHODS

Because of the equivocal evidence concerning the ability of breastfeeding to delay the onset or reduce the severity of atopic dermatitis, we have analyzed the fatty acid composition of breast milk from the mothers of children with newly developed disease with the use of gas chromatography.

RESULTS

Breast milk lipids from mothers of children with newly developed atopic dermatitis had increased proportions of linoleic acid and significantly decreased proportions of its long chain polyunsaturated derivatives compared with a control group. The ratio of linoleic acid to the sum of its metabolites, gamma-linolenic acid, dihomo-gamma-linolenic acid, and arachidonic acid was 11.78 in the atopic group and 9.02 in the control group (p < 0.01).

CONCLUSIONS

These results are consistent with previous findings of an abnormal fatty acid status in atopic subjects and may account for some of the inconsistent results from studies of the effect of breastfeeding on the subsequent development of atopic dermatitis. We conclude that further studies to examine the effects of supplementation of the diet of breastfeeding mothers with long chain polyunsaturates should be done.

Prevention of atopic diseases in high risk babies (long-term follow-up)

Several studies have demonstrated that dietary and environmental manipulations in the first months of life have a protective effect on the development of allergic diseases in babies "at risk" of atopy. We have prospectively followed up 174 "high risk" infants who underwent dietary and environmental manipulations, such as exclusive breast-feeding for the first 6 months of life, supplemented if necessary with soy-protein formula (Isomil, Abbott), delayed weaning beyond the 6th month of life, and rigorous environmental manipulations for the elimination of house-dust mite and passive smoking. The low prevalence of atopic disease (10%) and the trivial course of the allergic manifestations in this "at risk" population confirm the effectiveness of this preventive program. Moreover, this study demonstrates that the incidence of atopic dermatitis peaks at 6 months, and decreases until it disappears. Food allergy appears only at 6 months and may disappear later. The incidence of asthma peaks at 6 and 36 months and decreases at low levels in the intervals. Allergic rhinitis develops not sooner than 36 months.

Allergenicity and nutritional adequacy of soy protein formulas

Soy protein formulas are used for different conditions, including cow milk protein allergy, lactose and galactose intolerance, and severe gastroenteritis. Feeding soy protein formulas to normal term infants is associated with normal growth, normal protein nutritional status, and normal bone mineralization. Recent studies of infants fed soy protein formulas exclusively during the first months of life revealed no immunologic abnormality; however, the use of such formulas for management of cow milk protein allergy and for prevention of atopy is controversial. Although in the past decade many studies have stressed soy allergenicity, soy allergenicity has been confirmed by the challenge test in only a few studies. In this article we review the studies dealing with the allergenicity of soy protein formulas. We also present our own data on their use in the prevention and management of cow milk protein allergy.

New strategies for the prevention and treatment of allergic rhinitis in children

Allergic rhinitis (AR) is a very common disease in children, often underdiagnosed and with underestimated complications. Its prevalence has increased during the last years, due to changes in environmental factors. The therapeutic strategy will include prevention by identification and eviction of the main allergens, associated to pharmacological therapy. Among antirhinitic drugs, the new generation of non-sedative specific antihistamines represent the main choice. We report our own experience with astemizole, one of these new antihistamines which confirms that astemizole is an effective and safe drug for the management of AR in children.

Soy hypersensitivity in children with food allergy

To evaluate humoral (IgE antibodies) and clinical (positive challenge test) soy hypersensitivity prevalence, we studied 317 children (271 boys and 100 girls) with a median age of 5 months (range 1-120) who visited the Division of Allergy and Clinical Immunology of the Pediatric Department of the University of Roma "La Sapienza" because of histories and symptoms suggestive of food allergy. Atopic dermatitis (AD) was present in 247/317 children (78%), diarrhea in 19 (6%), urticaria in 22 (7%), and rhinitis and/or asthma in 29 (9%). All children underwent diagnostic procedures including family and personal history, physical examination, PRIST, and RAST to cows milk (CM), egg, wheat, soy, and Dermatophagoides pteronyssinus (Dpt). Open challenge tests to soy were performed in the hospital under observation and with emergency equipment at hand. The prevalence of humoral sensitization to CM was 54%, to egg 46%, to Dpt 35%, to wheat 24%, and to soy 22%. Only five children had IgE only to soy; six to soy and egg; and 58 to soy, CM, and egg. Only ten children (3%) had positive challenge to soy and only five of them had IgE to soy. RAST had a sensitivity of 0.69, a specificity of 0.83, a negative predictive value of 0.77, and a positive predictive value of only 0.06.

Effect of flunisolide on nasal eosinophils and IgE, and symptom score in children with allergic rhinitis

We evaluated the effect of treatment with flunisolide nasal spray (100 micrograms/day for 3 months) in 24 children with allergic rhinitis on the following parameters: clinical symptoms, absolute number of peripheral and nasal eosinophils, and total IgE levels in nasal secretion. Therapy with flunisolide induced a significant reduction of clinical symptoms (p < 0.001), nasal eosinophils (p < 0.001) and nasal IgE concentration (p < 0.02), while it did not affect the number of peripheral eosinophils. These results indicate that flunisolide can reduce the allergic inflammation of the nasal mucosa.

Prevention of atopic disease in at risk newborns

At least 15% of children have at least one atopic disease and genetic factors play an important role in the development. Screening of family history and high serum cord IgE permits introduction of dietary and environmental measures to prevent atopy. Environmental, prenatal, perinatal factors, exposure to household allergens, infections, cigarette smoking, dietary factors, including those during pregnancy, duration of breast feeding, dietary measures during lactation, all have effects in modifying the atopic response.