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This article reviews information on the topics of asthma, atopic dermatitis, food allergy, and upper respiratory infections. The asthma section provides an in-depth look at sociodemographic factors contributing to asthma morbidity and the barriers to asthma control. New findings on the triggers and therapies of atopic dermatitis and new articles on formula allergy and peanut allergy are presented. Recent publications in the areas of sinusitis and upper respiratory infections are also reviewed.

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This article reviews information on the topics of asthma, allergic rhinitis, atopic dermatitis, food allergy, and upper respiratory infections. The asthma section includes a review of inhaled steroids and their potential side effects. New findings on the pathogenesis, triggers, and therapies of atopic dermatitis and new insights into food hypersensitivity reactions are presented. Recent publications in the areas of allergic rhinoconjunctivitis and upper respiratory infections are also reviewed.

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This review highlights updated information on the topics of atopic dermatitis, food allergy, asthma, allergic rhinitis, and upper respiratory infections. Recent finding on the pathogenesis, triggers, and therapies of atopic dermatitis are discussed. New insights into peanut allergy and formula intolerance are presented. Topics highlighted in the section on asthma include quality of life and quality of care. Recent publications in the areas of allergic rhinoconjunctivitis and upper respiratory infections are also reviewed.

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OBJECTIVES: Specific recommendations for administering the influenza vaccine to patients with egg allergy are based on limited scientific data. The objectives of this investigation were to determine the safety of a 2-dose administration of an influenza vaccine to patients with egg allergy and to evaluate the usefulness of skin testing with the influenza vaccine before administration. STUDY DESIGN: In this multicenter clinical trial, clinical histories of egg allergy were confirmed by skin testing with egg and, if possible, by oral challenges with egg. Subjects with egg allergy received the vaccine in 2 doses, 30 minutes apart; the first dose was one tenth and the second dose nine tenths of the recommended dose as determined by age. Subjects without egg allergy were recruited as control subjects and received 1 age-determined dose of the vaccine. Skin prick tests with the influenza vaccine were performed on all subjects. RESULTS: From 1994 to 1997, 83 subjects with egg allergy and 124 control subjects were evaluated. The content of ovalbumin/ovomucoid was 0.1, 1.2, and 0.02 micrograms/mL, respectively in the 1994-95, 1995-96, and 1996-97 influenza vaccines. Results of vaccine skin prick tests were positive in 4 subjects with egg allergy and in 1 control subject. All patients with egg allergy tolerated the vaccination protocol without any significant allergic reactions. CONCLUSIONS: These results demonstrate that patients with egg allergy, even those with significant allergic reactions after egg ingestion, can safely receive an influenza vaccine in a 2-dose protocol when the vaccine preparation contains no more than 1.2 micrograms/mL egg protein.

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This review highlights recent information on the topics of atopic diseases and upper respiratory infections. Recent findings on the costs and therapies of atopic dermatitis are discussed. New insights into egg allergy, peanut allergy, food-induced exercise anaphylaxis, and the management of food allergy are presented. Topics highlighted in the section on asthma include airway remodeling and anti-inflammatory therapy, leukotriene synthesis inhibitors and receptor antagonists, steroid resistance and alternative therapy, and new delivery systems. Recent publications in the areas of allergic rhinoconjunctivitis and upper respiratory infections are also reviewed.

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When infants with recurrent wheezing have a clinical course inconsistent with asthma, an extensive list of alternative diagnoses needs to be considered. Anatomic malformations, such as congenital heart disease, laryngotracheomalacia, and diaphragmatic hernia, should be considered for immediate medical stabilization and early surgical correction. Life-threatening infections such as bacterial epiglottitis, retropharyngeal cellulitis, and viral myocarditis require prompt intervention. A careful history and physical examination reveal important diagnostic clues that, in this case, prompted a directed evaluation to rule out common masqueraders of asthma such as foreign body aspiration, cystic fibrosis, gastroesophageal reflux, viral pneumonitis, or pulmonary tuberculosis. On occasion, such a search is unrevealing and a diagnostic challenge remains. In those situations, judicious use of modern technology to scrutinize anatomic (high-resolution computed tomography) and functional (infant pulmonary function tests) pathology, and justifiable invasive procedures such as bronchoscopy and lung biopsy, uncover the true diagnosis, allowing for optimal management.

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This review details the recent information on the topics of atopic diseases and upper respiratory infections. New findings about the therapy and psychosocial aspects of atopic dermatitis are discussed. Topics highlighted in the section on asthma include the adverse effects of inhaled corticosteroids, the use of beta-agonists, the role of immunotherapy in asthma, and new directions in asthma care. Recent publications in the areas of food allergy, allergic rhinoconjunctivitis, and upper respiratory infections are also reviewed.

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Atopic dermatitis (AD) is a chronic skin disorder associated with elevated serum IgE and colonization of the skin by Staphylococi which secrete toxins with superantigenic activity. The present study examined the immunomodulatory effects of toxic shock syndrome toxin (TSST)-1, a prototypic superantigen, on IgE synthesis by interleukin (IL)-4-stimulated peripheral blood mononuclear cells (PBMC) from five patients with AD and five normal subjects. TSST-1 inhibited IL-4-induced IgE synthesis by AD and normal PBMC (P < 0.05). In contrast, IgG synthesis was not similarly affected (P > 0.30). Inhibition of IL-4-induced IgE production was associated with induction of interferon (IFN)-gamma synthesis by TSST-1 (P < 0.02). Normal PBMC synthesized significantly more (P < 0.005) IFN-gamma than AD PBMC. A neutralizing antibody to IFN-gamma reversed TSST-1-induced suppression of IgE synthesis by the normal PBMC (P < 0.03), but not the AD PBMC. In AD, but not normal, PBMC anti-IFN-alpha antibody reversed the suppression of IgE synthesis induced by TSST-1. These results demonstrate that TSST-1 uses different mechanisms for modulation of IgE synthesis in AD versus normal PBMC. Furthermore, the reversal of TSST-1-induced suppression of IgE synthesis in AD PBMC by anti-IFN-alpha, but not anti-IFN-gamma, is consistent with the concept that AD is associated with defective Th1 cell function and enhanced monocyte activity.

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BACKGROUND: Atopic dermatitis (AD) is a chronic skin disease associated with increased IgE synthesis and colonization with Staphylococcus aureus secreting exotoxins, such as Toxic Shock Syndrome Toxin-1 (TSST-1). OBJECTIVES: In this study, we were interested in determining the in vitro effects of TSST-1 on IgE synthesis in peripheral blood mononuclear cells from patients with AD. METHODS: We stimulated peripheral blood mononuclear cells (PBMC) from AD patients with a wide range of TSST-1 concentrations and measured IgE synthesis by enzyme-linked immunosorbent assay (ELISA) after 14 days. RESULTS: We show herein that TSST-1 produced antagonistic effects on IgE synthesis by PBMC from AD patients, depending on the concentration used: IgE synthesis was inhibited at 1000 pg/mL (P < 0.05) and enhanced at 0.01 pg/mL (P < 0.01) of toxin. TSST-1 was found to induce the production of much higher amounts of interferon-gamma (IFN gamma) at 1000 pg/mL than at 0.01 pg/mL of toxin (P = 0.0001). More importantly, immunoglobulin E (IgE) synthesis was enhanced by TSST-1 at 1 pg/mL in the presence of antibodies blocking IFN gamma activity. The other immunoglobulin (Ig) isotypes were also increased after TSST-1 stimulation suggesting that the enhanced IgE synthesis was secondary to a polyclonal B cell activation rather than an isotype switch. TSST-1-stimulated IgE synthesis was T cell-dependent because purified tonsil B cells were only able to synthesize increased amounts of IgE when small numbers of T cells were added to the cultures. Anti-HLA-DR and anti-LFA-1 monoclonal antibodies (MoAb) inhibited TSST-1-enhanced IgE synthesis, suggesting that the bridging of the T cell receptor (TCR) and major histocompatibility complex (MHC) class II on B cells was necessary for activation of B cell differentiation. CONCLUSION: These data indicate that staphylococcal superantigens are able, at concentrations inducing low amounts of IFN gamma, to stimulate IgE synthesis by PBMC from AD patients, and suggest that staphylococcal toxins may contribute to elevated IgE synthesis in AD.

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Atopic dermatitis (AD) is a chronic allergic disease associated with toxin (superantigen)-producing Staphylococcus aureus skin infections, impaired delayed hypersensitivity responses, and the expansion of IL-4-secreting Th2 cells, as well as diminished IFN-gamma synthesis. IL-12 is known to induce IFN-gamma synthesis and to augment Th1 responses. In this study, therefore, we examined the potential role of IL-12 in the immunopathogenesis of AD. We show that, after stimulation with staphylococcal toxic shock syndrome toxin-1 (TSST-1) or IL-12, PBMC from patients with AD are deficient in their ability to produce IFN-gamma. PBMC from AD patients, however, produced normal quantities of IL-12 and expressed normal levels of IL-12R. Induction of IFN-gamma by TSST-1 was decreased by neutralizing anti-IL-12 Ab in normal donors, but not in AD patients. The latter observation is consistent with a defective response to IL-12 in AD PBMC. Because AD is associated with increased production of IL-4 and IL-10, we examined the effect of IL-4 on IL-12- or TSST-1-induced IFN-gamma production in normal donors. IL-4 inhibited IL-12-induced IFN-gamma production. Furthermore, Ab neutralization of IL-4 caused increased production of IFN-gamma in AD PBMC. However, neutralization of IL-10 activity caused an even greater augmentation of IFN-gamma production. Our data suggest that despite normal levels of IL-12 production and IL-12R expression, PBMC from AD patients are unable to generate normal IL-12-induced IFN-gamma responses. This defective response may be due to the excess production of IL-4 and IL-10 in this common allergic condition.

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Endogenous sulfite is generated as a consequence of the body's normal processing of sulfur-containing amino acids. Sulfites occur as a consequence of fermentation and also occur naturally in a number of foods and beverages. As food additives, sulfiting agents were first used in 1664 and approved in the United States as long ago as the 1800s. With such long experience with their use, it is easy to understand why these substances have been regarded as safe. They are currently used for a variety of preservative properties, including controlling microbial growth, preventing browning and spoilage, and bleaching some foods. It is estimated that up to 500,000 (< .05% of the population) sulfite-sensitive individuals live in the United States. Sulfite sensitivity occurs most often in asthmatic adults--predominantly women; it is uncommonly reported in preschool children. Adverse reactions to sulfites in nonasthmatics are extremely rare. Asthmatics who are steroid-dependent or who have a higher degree of airway hyperreactivity may be at greater risk of experiencing a reaction to sulfite-containing foods. Even within this limited population, sulfite sensitivity reactions vary widely, ranging from no reaction to severe. The majority of reactions are mild. These manifestations may include dermatologic, respiratory, or gastrointestinal signs and symptoms. Severe nonspecific signs and symptoms occur less commonly. Broncho-constriction is the most common sensitivity response in asthmatics. The precise mechanisms of the sensitivity responses have not been completely elucidated. Inhalation of sulfur dioxide (SO2) generated in the stomach following ingestion of sulfite-containing foods or beverages, a deficiency in a mitochondrial enzyme, and an IgE-mediated immune response have all been implicated.(ABSTRACT TRUNCATED AT 250 WORDS)

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