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Background Allergic IgE-mediated reactions to neuromuscular blocking agents ( NMBAs) are the main cause of immediate hypersensitivity reactions in anaesthesia; their predominant occurrence in the absence of previous exposure to NMBAs suggests a risk related to environmental exposure. Objective To investigate the prevalence of specific IgE to quaternary ammonium ions in two populations professionally exposed to quaternary ammonium compounds, in the north-eastern France. Methods The study had a retrospective follow-up design whereby apprentices were assessed after their 2-year training period as apprentices. The professionally exposed hairdresser populations ( n = 128) were compared with baker/pastry makers ( n = 108) and 'non-exposed' matched control subjects ( n = 379). Results We observed a 4.6-fold higher frequency of positive IgE against quaternary ammonium ions in hairdressers (HD), compared with baker/pastry makers (BP) and control (C) groups. The competitive inhibition of quaternary ammonium Sepharose radioimmunoassay (QAS-IgE RIA) with succinylcholine was significantly higher in HD, compared with BP and C groups, with inhibition percentage of 66.2 ± 7.4, 39.7 ± 6.0 and 43.8 ± 9.9, respectively ( P < 0.001). The specific IgE against quaternary ammonium ions recognized also two compounds widely used by hairdressers, benzalkonium chloride and polyquaternium-10, in competitive inhibition of IgE RIA. When considering the whole study population, hairdresser professional exposure and total IgE > 100 kU/L were the two significant predictors of IgE-sensitization against quaternary ammonium ions in the multivariate analysis of a model that included age, sex, professional exposure, increased concentration of total IgE (IgE > 100 kU/L) and positive IgE against prevalent allergens (Phadiatop®; P = 0.019 and P = 0.001, respectively). Conclusion and Clinical Relevance The exposure to hairdressing professional occupational factors increases Ig E-sensitization to NMBAs and quaternary ammonium ion compounds used in hairdressing. Besides the pholcodine hypothesis, our study suggests that repetitive exposure to quaternary ammonium compounds used in hairdressing is a risk factor for NMBAs sensitization. [ABSTRACT FROM AUTHOR]

Atopic dermatitis (AD) is an inflammatory skin disease whose lesions can have two stages: acute and chronic. In skin biopsies a biphasic pattern of cytokine expression has been shown, Th2 in acute lesions and Th1 in chronic AD lesions. We investigated the expression of an activation marker and a homing receptor, as well as cytokine production, in different peripheral blood T cell subpopulations from AD patients with chronic (Group A) and acute lesions (Group B) and controls. We evaluated 26 adult AD patients (12 Group A, 14 Group B) and 14 non-atopic controls. IgE was measured by immunoassay. CD4, CD8, cutaneous-lymphocyte-associated antigen (CLA) and human leucocyte antigen (HLA)-DR expression, and cytokine production (IL-2, IL-13, IFN-γ, TNF-α, IL-10, IL-4) were analysed in mononuclear cells by flow cytometry. In Group B there was a significant increase in eosinophil levels and a non-significant increase in IgE. In Group A we found an increase in CLA+CD4+ cells (8.19±1.84) compared with controls (4.83±0.53) ( P<0.05) and CD4+HLA-DR+ cells in the CLA+ subpopulation (45.54±15.40) compared with controls (30.49±6.07) ( P<0.05). In the CLA+CD4+ subpopulation, there was a significant increase in IL-4, IL-13 and TNF-α production in Group B (12.46±7.7, 11.26±5.97, 43.92±15.55) compared with controls (5.34±3.50, 4.54±1.78, 19.29±9.97) with no differences in Group A. Greater immunological differences were detected in peripheral blood from patients with acute compared with chronic lesions, especially in the circulating T cell-subset with skin tropism that preferentially responded to cutaneous allergens. This is the first demonstration of phenotypic changes in circulating CLA+ T cells between AD patients with acute and chronic lesions. [ABSTRACT FROM AUTHOR]

Focuses on a particular subgroup of type B reactions, adverse drug reactions where an immunological basis is involved in the production of the adverse reaction. Description of approaches to understand the mechanisms involved; Prediction of possible causes and factors that can influence the appearance of reactions.

Background Previous observations indicate that in some instances subjects allergic to penicillins may experience an allergic reaction alter taking the drug by one route but have good tolerance after being administered the same drug by a different route. Objective The purpose was to establish if cloxacillin (CLX) induced a selective response only after oral route administration in a suspected case and to study if there were differences between the oral and parenteral formulations. Methods Skin tests were carried out using benzylpenicillin (BP) conjugated to poly-L-lysine (BPO-PLL), minor determinant mixture of benzylpenicillin (MDM), ampicillin (AMP), amoxicillin (AX) and cloxacillin (CLX), Radioallergosorbent assay (RAST) was carried out using BPO-PLL, AX-PLL and CLX-PLL sensitized discs. In the case the skin tests and RAST were negative, a controlled challenge administering the drug by both oral and parenteral route was made. Urine samples were taken at prechallenge (basal levels) and at three periods after challenge (1-3, 3-6 and 6-9 h). Analysis of oral and parenteral formulations was made by HPLC chromatography. Results All skin tests and RASTs were negative. With the challenge tests the patient tolerated parenteral BP and oral phenoxymethyl penicillin (PV) and oral and parenteral AMP up to therapeutic concentrations. Parenteral CLX (500mg) was also tolerated but 30 min after administering 50 mg by the oral route progressive generalized erythema with pruritus, facial angioedema and tachycardia developed. Urine samples taken during the challenge tests showed an increased excretion of N-methyl histamine (N-MH) 3h after challenge with oral CLX but no change in N-MH levels after challenge with parenteral CLX or the other penicillins, indicating that histamine was released during the allergic episode with oral CLX. HPLC analysis of the oral and parenteral CLX formulations indicated that there were no differences and that neither polymers nor other contaminant materials were present. Conclusion Although the nature of the allergenic determinant involved in the induction of the reaction is not yet known, the oral route may have favoured the production of a metabolite not generated by the parenteral route. [ABSTRACT FROM AUTHOR]

Although the different vespid species of the genus Polistes are found all over the world, studies about allergy sensitization to these species have been made mainly in North America. We studied the specific IgE in a large group of sera from patients sensitized to Polistes dominulus (PD) and determined the crossreactivity with another important European Polistes (P. gallicus [PG]) and with five American relevant species of this genus: P. exclamans (PE), P. fuscatus (PF), P. metricus (PM), P. annularis (PAN) and P. apachus (PAP). Studies indicated that 96 7% of sera with IgE positive to PD were positive to PG. No case positive to just PG was found. The comparison of these two European species with the American relatives indicated that most cases were positive to all the insects although there were significant differences in the radioallergosorbent test (RAST) value. These results were confirmed by RAST inhibition studies, and indicate that although the European and American species are closely related, species specific allergenic differences exist. These data suggest that in vivo studies should be carried out in order to determine the sensitivity and specificity of the European venoms compared with the American species. [ABSTRACT FROM AUTHOR]

Analyzes the different novel aspects of allergic reactions to betalactams. Specific determinants; Clinical studies including crossreactives; Contribution of cephalosporins; Novel methods for in vitro evaluation.

Immunological mechanisms implicated in drug allergic reactions are not yet well understood, but there is 'in vivo' and 'in vitro' evidence that T lymphocytes are involved in these hypersensitivity reactions. The cutaneous lymphocyte-associated antigen (CLA) is the skin homing receptor and is involved in targeting a skin-selective memory T lymphocyte to cutaneous sites of chronic inflammation. We have seen that CLA expression is increased in circulating T lymphocytes of patients who develop a drug allergic cutaneous reaction, these cells are activated and their CLA values tend to become normal in parallel with the disappearance of skin symptoms, demonstrating that CD3[sup +] CLA[sup +] cells are involved in the immunological mechanisms responsible for the pathogenesis of the chronic inflammation process in cutaneous drug reactions. [ABSTRACT FROM AUTHOR]

Background Ampicillin (AMP) is a drug that has been prescribed extensively. Reactions that have been reported include exanthema, desquamative contact eczema, urticaria and anaphylaxis. Experimental evidence indicates that the side chain of AMP is a structure that may induce a selective immune response either at the humoral or lymphocyte T-cell level. With regard to IgE reactions, the selectivity and specificity of the response needs to be studied in humans. Objectives To study the specificity of the IgE response in a group of subjects who had an immediate allergic reaction after the administration of AMP. Methods Subjects developing an immediate response (anaphylaxis or urticaria) after the administration of AMP or an aminopenicillin derivative with the same side chain as AMP were studied. Skin tests were made to determinants generated from benzyl penicillin (BP): benzyl penicilloyl (BPO) and minor determinant mixture (MDM), as well as amoxicillin (AX) and AMP. Specific IgE antibodies were determined to benzyl penicilloyl polylisine (BPO-PLL), amoxicilloyl-polylisine (AX-PLL) and ampicilloyl-polylisine (AMP-PLL). The specificity of the IgE antibody response was studied by RAST and RAST inhibition. Subjects were classified in three categories: group A: those who were skin test and/or RAST positive to determinants derived from benzylpenicllin, group B: those who were negative to determinants derived from benzylpenicillin but were skin test and/or RAST positive to determinants derived from AX and AMP and group C: those who were exclusively positive to determinants derived from AMP. Results A total of 48 subjects was included in the study. In group A there were 35 cases, in group B 10 cases, and in group C three cases. RAST inhibition studies showed that in some instances the side chain of AMP could induce specific responses with a variable degree of crossreactivity between BP and AX. Conclusions Athough AMP can induce an immediate IgE response in subjects allergic to betalactams and the structure of the side chain may contribute to the specificity of the response, our results indicate that in most instances crossreactivity with the other penicillins exists and that in the groups studied selective reactions to just AMP derived determinants were uncommon. [ABSTRACT FROM AUTHOR]

Allergic reactions to Hymenoptera stings are frequently observed all over Europe. Rarely they may induce long-standing morbidity or even be fatal. Several investigations have shown that the emergency treatment given to these patients is often inadequate. Cutaneous symptoms respond well to antihistamines and also to adrenaline. Adrenaline is the mainstay for outside hospital treatment of more severe reactions involving the respiratory tract (bronchial asthma, laryngeal oedema) and the cardiovascular system (anaphylactic shock). Inhaled adrenaline is especially useful in respiratory symptoms, while parenteral application of adrenaline is prefered for shock treatment. All patients with severe respiratory or cardiovascular reactions must be hospitalized, treated under intensive care conditions and observed for at least 24 hr. Emergency medications including adrenaline for inhalation or for self-injection must be given to all patients with a history of systemic allergic reactions to hymenoptera stings. These patients must also get instructions for safety measures to avoid further stings. They should be referred to an allergist in order to evaluate the indication for venom immunotherapy. [ABSTRACT FROM AUTHOR]

Comments on advances made in the understanding of adverse drug reactions with an immunological basis (ADRIB). Requirement of an integrated approach from different specialties; Pattern of reactions to drugs; Symposium to update advances in the field.