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Food allergy affects approximately 2% of the general US population, and its prevalence seems to be increasing. Despite the potential for a fatal outcome, no definitive therapies are available for food allergy. This article reviews novel approaches for the diagnosis and treatment of food allergy. Improved diagnostic methods include more precise in vitro and in vivo tests for immunoglobulin E-mediated food allergies, in vitro assays for predicting development of oral tolerance, and novel noninvasive tests for cell-mediated food allergies such as patch testing, cytokine assays, and detection of eosinophil activation markers. Several promising novel immunomodulatory approaches to food allergy are discussed, including monoclonal anti-immunoglobulin E; probiotics; traditional Chinese medicine; and immunotherapy with modified food proteins, peptides, bacterial adjuvants, and immunostimulatory sequences.

BACKGROUND:Infantile food protein-induced enterocolitis syndrome (FPIES) is a severe, cell-mediated gastrointestinal food hypersensitivity typically provoked by cow's milk or soy. Solid foods are rarely considered a cause. OBJECTIVE:To describe the clinical characteristics and natural history of FPIES provoked by solid foods. METHODS:Patients with FPIES induced by solid foods were identified and their clinical course compared with a control group with FPIES caused by cow's milk and/or soy evaluated over the same time period. RESULTS:Fourteen infants with FPIES caused by grains (rice, oat, and barley), vegetables (sweet potato, squash, string beans, peas), or poultry (chicken and turkey) were identified. Symptoms were typical of classical FPIES with delayed (median: 2 hours) onset of vomiting, diarrhea, and lethargy/dehydration. Eleven infants (78%) reacted to >1 food protein, including 7 (50%) that reacted to >1 grain. Nine (64%) of all patients with solid food-FPIES also had cow's milk and/or soy-FPIES. Initial presentation was severe in 79% of the patients, prompting sepsis evaluations (57%) and hospitalization (64%) for dehydration or shock. The diagnosis of FPIES was delayed, after a median of 2 reactions (range: 2-5). Thirty patients with typical cow's milk- and/or soy-FPIES were identified for comparison. Overall, 48% of the 44 infants with FPIES were reactive to >1 food protein, and the risk for multiple food hypersensitivity approached 80% in the infants with solid food or soy-induced FPIES. None of the patients developed FPIES to maternally ingested foods while breastfeeding unless the causal food was fed directly to the infant. CONCLUSIONS:Cereals, vegetables, and poultry meats, typically regarded as of low allergenic potential, must be considered in the evaluation of FPIES, particularly in infants previously diagnosed with FPIES to cow's milk or soy, and as an initial cause in patients who have been exclusively breastfed. Infants with FPIES are at risk for multiple dietary protein hypersensitivities during an apparent period of immunologic susceptibility. Pediatricians should consider FPIES in the differential diagnosis of shock and sepsis.

BACKGROUND:Montelukast is a leukotriene antagonist approved for the treatment of childhood asthma in children age 2 years and older. There are limited studies on its effects on allergic asthma in children. OBJECTIVE:We sought to evaluate montelukast's effects on upper and lower airway responses to intense cat allergen exposure. METHODS:In a double-blind, placebo-controlled, cross-over trial 18 subjects aged 6 to 14 years with cat-induced asthma were randomly assigned to receive 1 week each of either montelukast or placebo, followed by a 1-hour cat challenge in an environmental exposure unit. Upper and lower respiratory tract symptoms were rated, and spirometry and acoustic rhinometry were performed. Challenges were stopped early if the subject became too uncomfortable or had a greater than 50% decrease in FEV1. RESULTS:Overall changes in FEV1 were significantly different with montelukast treatment and remained significant after adjusting for allergen level (P =.02; adjusted P =.01). Lower respiratory tract symptom scores were significantly reduced with montelukast versus placebo (P =.007) but lost significance after adjusting for allergen level (P =.16). Challenge length was significantly longer with montelukast versus placebo (P <.001) and remained significant after adjusting for allergen level (P =.019). Montelukast did not significantly affect upper respiratory responses, as measured by means of symptom scores (P =.43) and changes in acoustic rhinometry (P =.078). CONCLUSIONS:Montelukast was significantly more effective than placebo in attenuating lower respiratory responses and extending challenge length when cat-sensitive children with mild persistent asthma were exposed to high levels of cat allergen.

BACKGROUND:Food allergies may affect up to 6% of school-aged children. OBJECTIVES/OBJECTIVE:To conduct a telephone survey to characterize food-allergic reactions in children (defined as those aged 3-19 years in this study) with known food allergies in schools and preschools and to determine mechanisms that are in place to prevent and treat those reactions. DESIGN/METHODS:The parents of food-allergic children were contacted by telephone and asked about their child's history of food-allergic reactions in school. The schools the children attended were contacted, and the person responsible for the treatment of allergic reactions completed a telephone survey. RESULTS:Of 132 children in the study, 58% reported food-allergic reactions in the past 2 years. Eighteen percent experienced 1 or more reactions in school. The offending food was identified in 34 of 41 reactions, milk being the causative food in 11 (32%); peanut in 10 (29%); egg in 6 (18%); tree nuts in 2 (6%); and soy, wheat, celery, mango, or garlic in 1 (3%) each. In 24 reactions (59%), symptoms were limited to the skin; wheezing occurred in 13 (32%), vomiting and/or diarrhea in 4 (10%), and hypotension in 1 (2%). Also, 15 (36%) of the 41 reactions involved 2 or more organ systems, and 6 (15%) were treated with epinephrine. Fourteen percent of the children did not have a physician's orders for treatment, and 16% did not have any medications available. Of the 80 participating schools, 31 (39%) reported at least 1 food-allergic reaction within the past 2 years and 54 (67%) made at least 1 accommodation for children with a food allergy, such as peanut-free tables, a peanut ban from the classroom, or alternative meals. CONCLUSIONS:It is common for food-allergic children to experience allergic reactions in schools and preschools, with 18% of children having had at least 1 school reaction within the past 2 years. Thirty-six percent of the reactions involved 2 or more organ systems, and 32% involved wheezing. Every effort should be made to prevent, recognize, and appropriately treat food-allergic reactions in schools.

Autoimmune diseases are rare in patients with severe combined immunodeficiency (SCID). The authors describe an 11-month-old infant girl with SCID with fatal warm autoimmune hemolytic anemia (AIHA) resulting from IgM autoagglutinins. Serologic evaluation revealed IgM autoantibodies that caused in vitro hemagglutination at 37 degrees C. The patient had clinical evidence of ongoing hemolysis and agglutination despite aggressive treatment. She had three strokes and died 6 weeks after unsuccessful bone marrow transplantation. Autoimmune disease is an unexpected complication of SCID. The presence of warm reactive IgM autoagglutinins in AIHA confers a dismal prognosis.

Two patients with severe combined immunodeficiency and enterovirus infections were successfully treated with pleconaril. There were no adverse affects.

Pneumococcal infections are an important cause of morbidity and mortality in children with sickle-cell disease (SCD). Pneumococcal conjugate vaccines (PCVs) are immunogenic in healthy infants <2 years of age but have not been evaluated in young children with SCD. Infants with SCD were immunized with a 7-valent PCV (Wyeth-Lederle Vaccines & Pediatrics) at 2, 4, and 6 months of age. A booster dose of 23-valent pneumococcal polysaccharide vaccine (PPV; Pnu-Immune) was administered at 24 months of age. Antipneumococcal type 6B and 14 serum opsonic activity was measured to assess the biologic function of the antibody. Following the administration of three doses of PCV, opsonic activity against serotype 6B increased from 4. 8% at 2 months to 33.5% at 7 months, with a subsequent decline to 8.1% at 12 months and 7.5% at 24 months and with an increase to 30.7% at 25 months after administration of a booster dose of PPV. Similar trends were seen with serotype 14 (opsonic activities were 9.4% at 2 months, 24.9% at 7 months, 16.5% at 12 months, and 12.6% at 24 months, and the opsonic activity was 27.3% 1 month after the administration of PPV). Serum opsonic activity correlated with antibody levels for both serotypes. PCV induces serum opsonic activity in infants with SCD. Antipneumococcal serum opsonic activity correlates with antibody levels.

Intravenous immunoglobulin is used as a replacement therapy in primary immunodeficiency diseases as well as an immunomodulatory agent in a variety of autoimmune and inflammatory disorders. The mechanisms of intravenous immunoglobulin action are complex and, for some disorders, not well understood. This paper reviews the recent literature and discusses approved, new, and controversial indications for intravenous immunoglobulin therapy, with special emphasis on its mechanism of action.