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Oral Challenge (oral + challenge)
Selected AbstractsCharacterization of allergens secreted by Anisakis simplex parasite: clinical relevance in comparison with somatic allergensCLINICAL & EXPERIMENTAL ALLERGY, Issue 2 2004M. L. Baeza Summary Background Diagnostic methods for the study of allergic reactions to Anisakis simplex (A.s.) based on whole-body extracts of the larva are clearly insufficient. Objectives To study the allergenicity of the proteins secreted by the parasite. Comparison with somatic antigens and determination of their clinical importance in allergic patients were also addressed. Methods An excretory/secretory (E/S) extract was produced by culturing third-stage A.s. larvae. It was used to perform immediate skin tests and to determine specific IgE in 10 patients diagnosed with allergy to A.s. Both tests were compared with the results obtained with the whole-body extract (somatic (S)). The molecular weight (MW) of their allergens was determined by immunoblotting, and a single-blind placebo-controlled oral challenge with E/S proteins was performed. Finally, allergens' resistance to gastric pepsin and acid pH was explored. Results A.s. larvae secreted allergens more potent than those present in the S extract. The skin prick test wheal area produced by E/S molecules and the absorbance obtained in the determination of specific IgE with these allergens (ELISA) were 5.8 times bigger than those obtained with S extract. MW allergens of 72 and 56 kDa in E/S extracts and those of 56, 48 and 43 kDa in S extract were recognized by more than 50% of the patients. Partial cross-reactivity between them was revealed by immunoblotting inhibition studies. Oral challenge with E/S extract (up to 479 ,g) was negative in all the patients. Treatment of E/S proteins with gastric pepsin inhibited the binding of the E/S allergens for specific IgE. The acid pH did not affect the overall binding of IgE to E/S extract. It decreased by 15.23% and 19.96% at pH 4 and 2, but the difference was not statistically significant. Conclusion A.s. secretes allergens more potent than somatic antigens and should be used in the diagnostic procedures. These allergens are inactivated by the pepsin, which supports the theory that live larva is necessary to induce an allergic reaction in most of the patients. [source] Oral challenges are needed in the diagnosis of ,-lactam hypersensitivityCLINICAL & EXPERIMENTAL ALLERGY, Issue 1 2008P. J. Bousquet Summary Background ,-lactams continue to remain the most commonly involved drug family in allergic drug reactions. They are often essential and there is a cost-effective and favourable risk-benefit ratio for the exploration of all suspicions of ,-lactam allergy. A firm diagnosis is always based on skin tests and sometimes on provocation tests. Recommendations have been published by allergy societies and distinguished scientists but they are not always concordant and can lead to some confusion for the practicing allergologist. The situation has even worsened since the world wide withdrawal of these penicillin determinants and since the predominance of amoxicillin and cephalosporin prescriptions in most countries. Objective , Method In a recent article, it was stated that patients with a penicillin allergy history and negative skin tests to major and minor penicillin determinants are at a low risk of relapse (0,5%) when receiving a ,-lactam. In this paper, our Drug Allergy and Hypersensitivity Database, a cohort database, was used to demonstrate that this statement is false. Standardized European Network for Drug Allergy questionnaires, skin test and challenge procedures were followed. Results One-thousand two-hundred and eighteen subjects, 69.8% of female, 51.7% of atopics, were included. 21.1% had a true ,-lactam allergy confirmed by skin tests (178, 69.3%) or by drug provocation (79, 30.7%). 17.4% of the patients with negative skin tests to major and minor penicillin determinants were positive for a ,-lactam. Conclusion In the diagnosis of ,-lactams allergy, if all skin tests are negative, skin tests with other determinants and provocation tests under strict surveillance are mandatory. [source] Cross-reactivity between nickel and palladium demonstrated by systemic administration of nickelCONTACT DERMATITIS, Issue 1 2005M. Hindsén Concomitant patch test reactions to nickel and palladium have frequently been reported in patients undergoing investigation because of suspected allergic contact dermatitis. Theoretically, these reactions can be explained by multiple, concomitant, simultaneous sensitization as well as cross-sensitization. We studied whether concomitant reactions to nickel and palladium could represent cross-sensitization in females hypersensitive to combinations of nickel, palladium and cobalt. Females were patch tested with serial dilutions of nickel sulfate, cobalt chloride and palladium chloride on the upper back. 1 month later, when the patch test reactions were gone, the patients were randomized into 2 groups that were challenged orally with either nickel or placebo. 1 day later, the areas of previous positive patch test reactions were read in a blind way looking for flare-up reactions. Nickel provocation but not placebo yielded flare-up reactions on sites previously tested with nickel (P = 0.012) and palladium (P = 0.006), but were also observed on sites previously tested with cobalt, even though this was not statistically significant. Flare-up reactions of previous patch test reactions to nickel and palladium after oral challenge with nickel speak in favour of a cross-reactivity mechanism. [source] Cervical sympathectomy causes alveolar bone loss in an experimental rat modelJOURNAL OF PERIODONTAL RESEARCH, Issue 6 2009Y. Kim Background and Objective:, Periodontal disease, a pathological destructive inflammatory condition, is characterized by alveolar bone loss. Recent studies have suggested a correlation between the sympathetic nervous system and bone remodeling. To confirm the importance of the sympathetic nervous system in bone resorption, we investigated the effects of superior cervical ganglionectomy and oral challenge with Porphyromonas gingivalis on alveolar bone loss in rats. Material and Methods:, Rats were divided into three groups: group A underwent a sham operation as the control group; group B underwent superior cervical ganglionectomy; and group C underwent a sham operation and oral challenge with P. gingivalis. Horizontal alveolar bone loss was evaluated by measuring the distance between the cemento-enamel junction and the alveolar bone crest. Cytokine gene expression in the gingival tissues was assessed using reverse transcription,polymerase chain reaction analyses. The furcation areas of the mandibular molars were examined histologically. Results:, Both superior cervical ganglionectomy and oral challenge with P. gingivalis resulted in accelerated alveolar bone loss. Gingival tissues in the superior cervical ganglionectomy group showed increased expression of the cytokines interleukin-1alfa, tumor necrosis factor-alfa and interleukin-6. The density of neuropeptide Y-immunoreactive fibers was decreased following superior cervical ganglionectomy. Osteoclasts were observed in the superior cervical ganglionectomy and P. gingivalis- challenged groups. Conclusion:, Both superior cervical ganglionectomy and oral challenge with P. gingivalis induced alveolar bone loss. These results provide new information on the occurrence of alveolar bone loss, in that both oral challenge with P. gingivalis and superior cervical ganglionectomy are important accelerating factors for alveolar bone loss. Thus, we suggest that the sympathetic nervous system is linked with the prevention of alveolar bone loss. [source] Chronic antigen ingestion protects ovalbumin sensitized mice from severe manifestation of Leishmania major infectionPARASITE IMMUNOLOGY, Issue 11-12 2008J. C. S. SALDANHA SUMMARY In the present work, the development of experimental leishmaniasis was examined in sensitized BALB/c mice that were chronically fed with antigen. After an oral challenge with egg white solution, the ovalbumin (Ova)-sensitized mice showed an increase in serum anti-Ova IgE and IgG1 antibodies. Lesions induced by Leishmania major infection were reduced by the ingestion of Ova in sensitized mice, as assessed by reduced footpad growth, lower parasite loads and improved pathological outcome compared to sham sensitized mice. Moreover, such findings were connected to a shift to a Th1 response involving higher IFN-, production and serum levels of IgG2a anti- Leishmania antigens. The data appear to corroborate the suggestion that chronic ingestion of an antigen by sensitized mice modulates the immunological system through a shift in cytokine release, exhibiting a healing response and resistance to L. major infection. [source] A previous infection with Toxoplasma gondii does not protect against a challenge with Neospora caninum in pregnant sheepPARASITE IMMUNOLOGY, Issue 3 2001E.A. Innes Sheep immunized with Toxoplasma gondii (Toxovax®) prior to pregnancy were tested for their ability to withstand a challenge at 90 days gestation with 107 Neospora caninum (NC1) tachyzoites. The antibody responses in sheep following immunization with T. gondi were specific for T. gondii whereas peripheral blood mononuclear cells responded to both T. gondii and caninum antigen in vitro. This suggested that there was induction of crossreactive immune recognition in the sheep, at least at the cellular level. Following challenge of sheep at mid-gestation with N caninum, no febrile responses were recorded in the group of sheep which had previously received Toxovax® while significant febrile responses were recorded in the group of sheep which received N challenge alone. Antibody responses to N developed in all sheep following challenge and antibody responses to T,gondii were boosted in the group of sheep which had previously been immunized with Toxovax®. No antibodies to were observed in the sheep which received the challenge alone. Peripheral blood mononuclear cells from both groups of sheep responded to T.gondii N.caninum antigen invitro and interferon gamma was present in the cell-free supernatant from activated cells. However despite evidence of the induction of crossreactive immunity between T.gondii N.caninum this was not sufficient to prevent foetal death. The group of sheep which had received Toxovax® prior to pregnancy and the group of sheep which only received the N.caninum challenge experienced 100% foetal death compared with 0% in the unchallenged control group. Vaccination prior to pregnancy with Toxovax® did protect against foetal death following oral challenge at 90 days with 2000 oocysts which caused 100% foetal death in a control challenge group. [source] Safety and efficacy of a new extensively hydrolyzed formula for infants with cow's milk protein allergyPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 4 2008B. Niggemann Cow's milk protein allergy (CMPA) is best treated by complete elimination of cow's milk from the diet. For infants with CMPA who cannot be breast-fed, formulas based on extensively hydrolyzed proteins or on amino acids are the preferred substitutes for cow's milk-based formulas. In this study, we compared the tolerance and growth of infants with CMPA who were fed a new extensively hydrolyzed formula containing lactose (eHF) with those who were fed an amino acid formula (AAF). This was a prospective, multi-center, randomized, reference-controlled study. Seventy-seven infants <12 months old with suspected CMPA were enrolled. In 66 of these, CMPA was confirmed by oral challenge in a double-blind, placebo-controlled food challenge (DBPCFC) or by a medical history of severe allergic reaction to cow's milk and a positive skin prick test. These infants were then tested for their reaction to eHF and AAF in a DBPCFC. All infants tolerated both formulas and were randomized to receive either eHF (n = 34) or AAF (n = 32) for 180 days. Growth (weight, length, and head circumference) and tolerance [skin, gastro-intestinal, and respiratory tract symptoms of allergy] were evaluated after 30, 60, 90, and 180 days. There were no significant differences between the two groups in any of the growth measurements. Length and head circumference were similar to Euro-growth standards, but weight was slightly lower. Gastro-intestinal and respiratory tract symptoms of allergy were also similar in the two groups. However, whereas SCORAD scores for atopic dermatitis remained constant throughout the study in infants-fed eHF, there was a slight decrease in those fed AAF. Infants-fed eHF had significantly fewer incidents of vomiting than infants-fed AAF and a significantly higher frequency of soft stools. The new eHF is safe and well tolerated in infants diagnosed with CMPA. [source] Oral vaccination trials with crayfish, Procambarus clarkii, to induce resistance to the white spot syndrome virusAQUACULTURE RESEARCH, Issue 15 2009Fei Zhu Abstract The potential of oral vaccination against white spot syndrome virus (WSSV) in crayfish Procambarus clarkii was investigated. The protective effect of binary ethylenimine (BEI)-inactivated WSSV was tested by oral vaccination, followed by an oral challenge with WSSV. The crayfish fed with feed pellets coated with BEI-inactivated WSSV showed a resistance to WSSV on the seventh day post vaccination (dpv). The relative percentage survival values were 60%, 70% and 75% for the vaccinated once, twice and thrice with inactivated WSSV. Following an intramuscular injection experiment, no mortality was recorded in the inactivated WSSV group and the negative control at 17 days post challenge. The cumulative mortalities in the heated WSSV group and WSSV group were 100%. Shrimp that survived the WSSV challenge on the seventh day after cessation of oral vaccination were positive for the presence of WSSV by a polymerase chain reaction assay specific for WSSV. This result indicated that inactivated WSSV could protect crayfish against WSSV by oral delivery. [source] Sensitization and allergy to turnip rape: a comparison between the Finnish and French children with atopic dermatitisACTA PAEDIATRICA, Issue 2 2009S Poikonen Abstract Aim: Finnish children with atopic dermatitis (AD) are frequently sensitized and show positive food challenge to turnip rape. We examined whether French children are also allergic to this oilseed plant and whether mustard could be the cross-reacting allergen. Methods: Turnip rape and mustard challenge was performed to 14 Finnish and 14 French children with atopic dermatitis and positive skin prick test to turnip rape. Specific IgE antibodies were measured by ImmunoCAP and enzyme-linked immunosorbent assay (ELISA). Results: Open labial or oral challenge to turnip rape was positive in 14 (100%) Finnish and five (36%) French children and mustard challenge in five Finnish and five French children. IgE antibodies to oilseed rape and mustard were slightly more frequent in the Finnish (100% and 93%) than in the French (93% and 71%) children but rare (4%) in the 28 matched controls. The same findings were true for IgE antibodies to purified 2S albumin allergens, which showed similar cross-wise IgE inhibition patterns. Conclusion: French children with atopic dermatitis show IgE antibodies to turnip rape, oilseed rape and mustard similarly to the Finnish children. 2S albumin allergens in the seeds of these plants are highly cross-reactive and therefore, they all could be important sensitizers in children with atopic dermatitis. [source] Allergen-specific antibody and cytokine responses, mast cell reactivity and intestinal permeability upon oral challenge of sensitized and tolerized miceCLINICAL & EXPERIMENTAL ALLERGY, Issue 1 2010C. Perrier Summary Background Food allergy has reached an epidemic level in westernized countries and although central mechanisms have been described, the variability associated with genetic diversity underscores the still unresolved complexity of these disorders. Objective To develop models of food allergy and oral tolerance, both strictly induced by the intestinal route, and to compare antigen-specific responses. Methods BALB/c mice were mucosally sensitized to ovalbumin (OVA) in the presence of the mucosal adjuvant cholera toxin, or tolerized by intra-gastric administrations of OVA alone. Antibody titres and cytokines were determined by ELISA, and allergic status was determined through several physiologic parameters including decline in temperature, diarrhoea, mast cell degranulation and intestinal permeability. Results OVA-specific antibodies (IgE, IgGs and IgA in serum and feces) were produced in sensitized mice exclusively. Upon intra-gastric challenge with OVA, sensitized mice developed anaphylactic reactions associated with a decline of temperature, diarrhoea, degranulation of mast cells, which were only moderately recruited in the small intestine, and increased intestinal permeability. Cytokines produced by immune cells from sensitized mice included T-helper type 2 cytokines (IL-5, IL-13), but also IL-10, IFN-, and IL-17. In contrast, all markers of allergy were totally absent in tolerized animals, and yet the latter were protected from subsequent sensitization, demonstrating that oral tolerance took place efficiently. Conclusion This work allows for the first time an appropriate comparison between sensitized and tolerized BALB/c mice towards OVA. It highlights important differences from other models of allergy, and thus questions some of the generally accepted notions of allergic reactions, such as the protective role of IFN-,, the importance of antigen-specific secretory IgA and the role of mucosal mast cells in intestinal anaphylaxis. In addition, it suggests that IL-17 might be an effector cytokine in food allergy. Finally, it demonstrates that intestinal permeability towards the allergen is increased during challenge. Cite this as: C. Perrier, A.-C. Thierry, A. Mercenier and B. Corthésy, Clinical & Experimental Allergy, 2010 (40) 153,162. [source] Utility of diagnostic tests in the follow-up of egg-allergic childrenCLINICAL & EXPERIMENTAL ALLERGY, Issue 10 2009Ma C. Diéguez Summary Background Better knowledge of the accuracy of a skin prick test (SPT) and specific IgE (sIgE) levels to egg allergens would help to identify persistent egg-allergic children, avoiding unnecessary risky challenges. This study was designed to assess the accuracy of a SPT and sIgE levels to egg allergens in order to determine persistent egg allergy in IgE-mediated allergic children after an egg-free diet. Methods Children below 16 years were prospectively and consecutively recruited. Inclusion criteria were: allergy to egg proteins (children with a positive clinical case of IgE-mediated egg allergy and a positive SPT to egg allergens and/or positive sIgE levels), and strict egg avoidance diet followed for at least 6 months. Clinical histories were recorded and all patients underwent SPTs, sIgE levels to egg allergens and the gold standard -a double-blind placebo-controlled egg challenge (DBPCFG). DBPCFG was interpreted without knowledge of the results of the other tests and vice-versa. A SPT and sIgE levels' ROC curves analysis was performed to compare the diagnostic performance of the different tests. Results Finally, 157 children were included in the study. One hundred out of these 157 children (63.7%) had a positive oral challenge. Ninety-six were male (61%), and the median age was 2.5 years. One hundred and three (66.9%) had atopic dermatitis. A 7 mm egg white prick test had a positive likelihood ratio (+LR) of 6.7, and a level of 1.3 KU/L egg white-sIgE had a +LR of 5.1. A 7 mm egg white SPT had a positive predictive value of 92.3% (95% CI 85.1,99.5), and for a 9 mm egg white SPT this value was 95.6% (95% CI 87.3,100.0). For egg white-sIgE, 1.5 KU/L had a positive predictive value of 90.4% (95% CI 82.4,98.4) and for 25 KU/L it was 100.0% (95% CI 100.0,100.0). SPTs with ovotransferrin and lysozyme showed the lowest accuracy, followed by yolk and ovalbumin SPTs. Conclusion This study is the first to evaluate both tests (SPT and sIgE levels) and all egg allergens to determine the persistence of egg allergy in IgE-mediated allergic children. Measuring the SPT and sIgE levels is useful to predict persistent allergy in these children, especially with the egg white complete extract. An oral challenge should not be performed in egg allergic paediatric patients with either an egg white prick test above 7 mm or a white egg-sIgE determination above 1.3 KU/L, because there is a 90% probability of remaining allergic. [source] Beta lactam allergy and resensitization in children with suspected beta lactam allergyCLINICAL & EXPERIMENTAL ALLERGY, Issue 5 2009J. Hershkovich Summary Background In patients who were clinically diagnosed as having beta lactam allergy and had negative skin tests, the rates of reported resensitization to beta lactams after subsequent exposures, vary significantly. Some allergists advocate skin testing before every exposure to beta lactams. Objective We sought to determine the true rate of beta lactam allergy and of resensitization in children with a positive history for suspected beta lactam allergy. Methods The study was conducted from July 1998 to May 2004, with follow-up during 2007. Beta lactam allergy tests with the major determinant and freshly prepared minor determinant mixtures were offered to history positive children. Negative skin tests were followed by oral challenge. The tests were performed again 1,5 months later in order to address the possibility of resensitization. Results Tests were performed on 166 children: 150 for penicillins alone, 14 for penicillin in combination with cephalosporins, and an additional 2 patients solely for cephalosporins. Only 10 children (6%) were positive in the initial evaluation, four by skin test and six by oral challenge. A second set of tests was performed in 98 children with a negative initial evaluation; only two children (2%) were resensitized. On a follow-up survey of 71 of the 96 patients, 59 (83%) had received beta lactams; only one had developed a minor rash after subsequent exposure to amoxicillin. Conclusions Most children with suspected beta lactam allergy were not allergic to beta lactams. Resensitization to beta lactam antibiotics in children in this study was infrequent. In children with a clinical diagnosis of beta lactam allergy and negative skin tests, repeated skin testing before every exposure is usually unnecessary. [source] Patterns of immunoglobulin G responses to egg and peanut allergens are distinct: ovalbumin-specific immunoglobulin responses are ubiquitous, but peanut-specific immunoglobulin responses are up-regulated in peanut allergyCLINICAL & EXPERIMENTAL ALLERGY, Issue 10 2007S. S. Tay Summary Background The clinical significance of food-specific IgG subclasses in food allergy and tolerance remains unclear. Specific IgG titres are often reported in non-standardized units, which do not allow comparisons between studies or allergens. Objective To quantify, in absolute units, ovalbumin (OVA)- and peanut-specific IgG levels in children with peanut or egg allergy (active or resolved) and in non-allergic controls. Methods Children aged 1,15 years were recruited. Peanut allergy was diagnosed by convincing history and a 95% predictive level of specific IgE; egg allergy or resolution was confirmed by oral challenge. Serum IgG, IgG1 and IgG4 levels (,g/mL) to OVA and peanut extract were quantified by ELISA. Results OVA- and peanut-specific IgG was detected in all subjects. In non-allergic controls (n=18), OVA-specific IgG levels were significantly higher than peanut-specific IgG (median ,g/mL IgG=15.9 vs. 2.2, IgG1=1.3 vs. 0.6, IgG4=7.9 vs. 0.7; P<0.01). There were no differences in OVA-specific IgG, IgG1 and IgG4 between egg-allergic (n=40), egg-resolved (n=22) and control (n=18) subjects. In contrast, peanut-specific IgG (median ,g/mL IgG=17.0, IgG1=3.3, IgG4=5.2) were significantly higher in peanut-allergic subjects (n=59) compared with controls and with non-peanut-sensitized but egg-allergic subjects (n=26). Overall, the range of IgG4 was greater than IgG1, and IgG4 was the dominant subclass in >60% of all subjects. Conclusion OVA-specific IgG levels of egg-allergic, egg-resolved or control groups are not distinguishable. Higher peanut-specific IgG levels are associated with clinical allergy, but the range of IgG titres of the allergic and control groups overlapped. Hence, OVA and peanut-specific IgG measurements do not appear to be of diagnostic value. Strong IgG responses to OVA may be a normal physiological response to a protein frequently ingested from infancy, whereas up-regulated IgG responses in peanut allergy may be indicative of a dysregulated immune response to peanut allergens. [source] Characterization of allergens secreted by Anisakis simplex parasite: clinical relevance in comparison with somatic allergensCLINICAL & EXPERIMENTAL ALLERGY, Issue 2 2004M. L. Baeza Summary Background Diagnostic methods for the study of allergic reactions to Anisakis simplex (A.s.) based on whole-body extracts of the larva are clearly insufficient. Objectives To study the allergenicity of the proteins secreted by the parasite. Comparison with somatic antigens and determination of their clinical importance in allergic patients were also addressed. Methods An excretory/secretory (E/S) extract was produced by culturing third-stage A.s. larvae. It was used to perform immediate skin tests and to determine specific IgE in 10 patients diagnosed with allergy to A.s. Both tests were compared with the results obtained with the whole-body extract (somatic (S)). The molecular weight (MW) of their allergens was determined by immunoblotting, and a single-blind placebo-controlled oral challenge with E/S proteins was performed. Finally, allergens' resistance to gastric pepsin and acid pH was explored. Results A.s. larvae secreted allergens more potent than those present in the S extract. The skin prick test wheal area produced by E/S molecules and the absorbance obtained in the determination of specific IgE with these allergens (ELISA) were 5.8 times bigger than those obtained with S extract. MW allergens of 72 and 56 kDa in E/S extracts and those of 56, 48 and 43 kDa in S extract were recognized by more than 50% of the patients. Partial cross-reactivity between them was revealed by immunoblotting inhibition studies. Oral challenge with E/S extract (up to 479 ,g) was negative in all the patients. Treatment of E/S proteins with gastric pepsin inhibited the binding of the E/S allergens for specific IgE. The acid pH did not affect the overall binding of IgE to E/S extract. It decreased by 15.23% and 19.96% at pH 4 and 2, but the difference was not statistically significant. Conclusion A.s. secretes allergens more potent than somatic antigens and should be used in the diagnostic procedures. These allergens are inactivated by the pepsin, which supports the theory that live larva is necessary to induce an allergic reaction in most of the patients. [source] Oral administration of an edible-mushroom-derived protein inhibits the development of food-allergic reactions in miceCLINICAL & EXPERIMENTAL ALLERGY, Issue 11 2003K.-Y. Hsieh Summary Background Food allergy is a common disease without effective treatment. Since strict elimination of food allergens may be difficult, strategies for effective intervention are urgently needed. Objective The aim was to investigate the prophylactic use of orally administrated FIP- fve, an immunomodulatory protein isolated from the edible mushroom Flammulina velutipes, in a murine model of food allergy. Methods BALB/c mice were immunized twice intraperitoneally with ovalbumin (OVA), at an interval of 2 weeks. Before and during each period of immunization, FIP- fve (200 ,g per mouse) or phosphate-buffered saline was given orally every other day with a total of five doses. Then OVA-specific antibodies and cytokine profiles were determined. Subsequently, the mice were orally challenged with OVA. Symptoms of anaphylaxis, levels of plasma histamine, and histology of intestines were examined. Results Mice receiving oral FIP- fve treatment during sensitization to OVA had an impaired OVA-specific IgE response with a Th1-predominant cytokine profile. These mice were protected from systemic anaphylaxis-like symptoms induced by subsequent oral challenge with OVA. Conclusion Oral administration of FIP- fve has a Th1-skewing effect on the development of the allergen-specific immune response, and may serve the purpose of immunoprophylaxis for food allergy and other allergic diseases. [source] High incidence of adverse reactions to egg challenge on first known exposure in young atopic dermatitis children: predictive value of skin prick test and radioallergosorbent test to egg proteinsCLINICAL & EXPERIMENTAL ALLERGY, Issue 10 2002G. Monti Summary Background Egg skin prick test (SPT) and/or radioallergosorbent test (RAST) positivity has been described in infants and children with a food allergy, or in infants at high risk of atopy who have never eaten eggs. Clinical reactions are also observed when some of these children or infants eat eggs for the first time. Objective and method A prospective study was made of 107 atopic dermatitis (AD) children (66 boys, 41 girls) aged 1,19 months (median 5 months) who had never ingested egg, to compare the outcome of a first oral egg challenge and the results of albumen and yolk SPTs and RASTs. Results The egg challenge (conducted at age 12,24 months: mean 16 months, median 15 months) was positive in 72/107 children (67.3%). The reactions were immediate or early (first 6 h) in 56/72 (77.8%). The most severe (all within the first 6 h) were one case of anaphylactic shock (1.4%), three cases of laryngeal oedema (4.1%) and one serious attack of asthma (1.4%). The skin weal diameter at and above which reactions always occurred was 5 mm for both albumen and yolk. They were, however, also observed in the complete absence of a weal. The outcome of the challenge was always positive when the specific IgEs (sIgE) for albumen and yolk were > 99 KU/L and , 17.5 KU/L, respectively. Here, too, reactions were noted even when sIgE levels were < 0.35 KU/L. Conclusion AD children who have never eaten eggs may be sensitized and display reactions at the first ingestion. The percentage of reactions in this series was by no means negligible. These findings were observed in children with mild as well as moderate,severe AD when first examined. SPT for albumen and yolk diameter , 5 mm, and sIgE for albumen > 99 KU/L and for yolk , 17.5 KU/L were 100% specific in predicting the outcome of the challenge. It may thus be concluded that children with AD whose SPT and/or RAST for albumen and/or yolk are equal to or higher than these cut-off values should not be subjected to the oral challenge when consideration is given to the introduction of egg in their diet. Even when these cut-offs are not reached, however, clinical reactions to the challenge cannot be ruled out a priori, and it should be preferably performed in a protected environment, such as a hospital. [source] Delayed- and immediate-type reactions in the atopy patch test with food allergens in young children with atopic dermatitisPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 1 2009A. C. A. Devillers In recent years, the atopy patch test (APT) has been suggested as an addition in the allergological work-up of children with atopic dermatitis (AD) and suspected food allergy. We initiated a prospective clinical study in children with AD younger than 3 yr, to evaluate the additional clinical value of the APT next to our own standardized allergological work-up in case of a suspected food allergy. One hundred and thirty-five children were included in the study. They were tested using the skin application food test (SAFT), the APT and measurement of specific IgE. The allergens used in the skin tests were freshly prepared food stuffs and included commercially available cow's milk (CM), the egg white of a hard boiled hen's egg and mashed peanuts in a saline solution. Allergy was defined using a flowchart incorporating the results from the SAFT, oral challenges (OCs) and elimination and (re)introduction periods. To determine the additional value of the APT next to the SAFT, we analyzed the SAFT negative patients per allergen and used an exact binary logistic analysis to evaluate the simultaneous effects of the APT and measurement of specific IgE, calculating mutually adjusted odds ratios (ORs) for positive APTs and specific IgE levels above 0.70 U/l. We found clinically relevant food allergies in 23% (egg white) to 28% (CM and peanut) of our study population. Positive SAFT reactions were observed in 14% (peanut), 16% (egg white) and 21% (CM) of our patient population. Next to the SAFT, we did not observe a significant additional value of the APT for the diagnosis of CM or egg white allergy, but we did find a significant additional value for the diagnosis of peanut allergy (OR = 11.56; p < 0.005, 2-sided). In clinical practice this statistically significant value does not exclude the need for OC and controlled elimination and (re)introduction periods due to the presence of false-negative as well as false-positive results in the APT. In conclusion, we could not find enough support for the current addition of the APT to our standardized allergological work-up in young children below the age of 3 yr with AD and suspected food allergy. At the moment the additional value of the classical delayed-type APT next to the SAFT seems to be very limited at best in this study population and does not justify the time-consuming nature of the skin test. [source] Diagnostic testing in suspected fluoroquinolone hypersensitivityCLINICAL & EXPERIMENTAL ALLERGY, Issue 11 2009C. S. Seitz Summary Background Because of their broad antibacterial activity in the gram-negative and gram-positive spectrum, high oral bioavailability, and good tissue penetration, fluoroquinolone antibiotics are widely used. Besides direct drug-related side-effects, fluoroquinolones may cause hypersensitivity reactions. Objective The aim of this retrospective analysis was to present the results of diagnostic testing in cases of clinically suspected fluoroquinolone-induced immediate or delayed hypersensitivity. Methods We studied 101 patients with a history of immediate or delayed hypersensitivity symptoms in temporal relation to treatment with a fluoroquinolone antibiotic using standardized skin testing, followed by oral challenges. Patients with anaphylaxis symptoms were further evaluated with in vitro tests. Results Fluoroquinolone hypersensitivity was excluded in 71 patients by tolerated oral challenge tests. During positive challenge tests, six patients (three out of these had positive and three had negative skin prick tests) developed anaphylaxis symptoms but the presumed IgE-mediated mechanism could not be confirmed by in vitro tests. Patch testing was constantly negative; however, in two patients a rash was induced by the challenge tests. Conclusion History alone leads clearly to a considerable over-estimation of fluoroquinolone hypersensitivity. Moreover, skin or in vitro tests do not seem to be very useful in identifying hypersensitive patients. Challenge tests appear to be necessary for definitely confirming or ruling out fluoroquinolone hypersensitivity. [source] | ||||||||||