Evaluation of the basophil activation test and skin prick testing for the diagnosis of sesame food allergy.

BACKGROUND: The prevalence of sesame food allergy (SFA) has increased over recent years, with the potential of anaphylactic reactions upon exposure. Oral food challenge (OFC) remains the diagnostic standard, yet its implementation may be risky. Commercial skin prick tests (SPT) have a low sensitivity. Investigation of alternate diagnostic methods is warranted. OBJECTIVE: To evaluate the utility of SPT and the basophil activation test (BAT) for SFA diagnosis. METHODS: Eighty-two patients with suspected SFA completed an open OFC to sesame or reported a recent confirmed reaction. Patients were administered skin prick tests (SPT) with commercial sesame seed extract (CSSE) and a high protein concentration sesame extract (HPSE) (100 mg/mL protein). Whole blood from 80 patients was stimulated with sesame seed extract (40-10 000 ng/mL protein) for BAT), assessing CD63 and CD203c as activation markers. RESULTS: Sixty patients (73%) had IgE-mediated reactions to sesame, and 22 (27%) did not react. Receiver operating characteristic (ROC) curve analysis demonstrated an area under the curve (AUC) of 0.87 for HPSE-SPT and 0.66 for CSSE-SPT. At 1000 ng/mL of sesame protein, induction of CD63 and CD203c was weakly but significantly associated with OFC eliciting dose by rank (Spearman's rho = -.42 (P < .01) and -.35 (P < .05) for CD63 and CD203c, respectively). By ROC analysis, the AUC was 0.86 for CD63 and was 0.81 for CD203c sesame-induced basophil expression. Using HPSE-SPT as a first test to definitively diagnose (n = 24) or rule-out (n = 5) SFA and BAT as a second test to diagnose the remainder results in the correct classification of 73 of 80 (91%) patients, leaving one false negative and 4 false positive patients. Two BAT non-responders remain unclassified by this algorithm. CONCLUSIONS & CLINICAL RELEVANCE: While prospective cohort validation is necessary, joint utilization of BAT and SPT with HPSE extract may obviate the need for OFC in most SFA patients.

NUT Co Reactivity - ACquiring Knowledge for Elimination Recommendations (NUT CRACKER) study.

BACKGROUND: Ambiguities exist regarding the diagnosis of tree-nut allergy, necessitating either their elimination or the performance of oral food challenges (OFCs). OBJECTIVE: To examine the coincidences of allergies among tree-nuts and improve diagnostic testing to minimize the need for OFC. METHODS: Eighty-three patients prospectively evaluated for walnut, pecan, cashew, pistachio, hazelnut, and almond allergy. A history of previous reactions was obtained, and standardized skin prick tests (SPTs) using finely ground tree-nut solution and basophil activation tests (BAT) were performed. Patients underwent OFC for each tree-nut they eliminated and to which a reaction in the previous 2 years was not documented. RESULTS: While most patients were sensitized to 5-6 tree-nuts, over 50% were allergic to only 1-2 tree-nuts. The highest rate of allergy in sensitized patients was observed for walnut (74.6%) and cashew (65.6%). The rate of co-allergy for most tree-nuts was <30%. Two-thirds of walnut- and cashew-allergic patients were also allergic to pecan and pistachio, respectively, while all pecan- and pistachio-allergic patients were allergic to walnut and cashew, respectively. Receiver-operating characteristic analysis for SPT and BAT was tree-nut dependent and yielded area under the curve (AUC) values ranging from 0.75 to 0.94. Knowledge of coincident allergies in these pairs along with the combination of SPT and BAT correctly distinguished allergic from tolerant patients for walnut (87%), pecan (66%), cashew (71%), and pistachio (79%). CONCLUSION: The data presented here should assist in differentiating between allergic and tolerant patients, decrease the need for OFC, and allow for appropriate elimination recommendations.

Changes in patient quality of life during oral immunotherapy for food allergy.

BACKGROUND: Quality of life (QOL) is impaired in patients with food allergy and improves following oral immunotherapy (OIT). However, the treatment itself is prolonged and demanding. We examined changes in patient QOL during OIT for food allergy. METHODS: The FAQLQ-PF was administered to children aged 4-12 years undergoing OIT for milk, peanut, or egg allergy, at the beginning and after 4 months of treatment. Patients were categorized as improved, unchanged, or diminished FAQLQ-PF (>0.5 point decrease, a change of ≤0.5 points, or >0.5 increase, respectively) and compared. Food-allergic patients not undergoing OIT served as controls. RESULTS: The Food Anxiety, Social and Dietary Limitation, and total FAQLQ-PF scores improved significantly during the study period (P=.001, P=.018, and P=.01, respectively) in treated but not in control patients, while the Emotional Impact did not. The change in the FAQLQ-PF was independent of the maximal tolerated dose at baseline or following four months of treatment, the pace of dose increase, or the number or severity of reactions experienced. The total FAQLQ-PF score was inversely associated with the score at baseline on multivariate analysis (regression coefficient=-0.56, P<.001). That was driven primarily by improvement in QOL scores in patients with high score (worse QOL) at baseline. Some patients with low FAQLQ-PF score (better QOL) at baseline deteriorated. CONCLUSIONS: QOL of patients with food allergy improves in some but deteriorates in others during OIT. Patients with impaired QOL at baseline improve significantly despite the treatment burden. Some patients with better QOL at baseline might deteriorate during OIT.

Clinical and laboratory 2-year outcome of oral immunotherapy in patients with cow's milk allergy.

Studies examining the long-term effect of oral immunotherapy in food-allergic patients are limited. We investigated cow's milk-allergic patients, >6 months after the completion of oral immunotherapy (n = 197). Questionnaires, skin prick tests, and basophil activation assays were performed. Of the 195 patients contacted, 180 (92.3%) were consuming milk protein regularly. Half experienced adverse reactions, mostly mild. Thirteen patients (6.7%) required injectable epinephrine. Higher reaction rate after immunotherapy was associated with more anaphylactic episodes before treatment and a lower starting dose (OR = 2.1, P = 0.035 and OR = 2.3, P = 0.035, respectively). Reaction rate in patients who were 6-15 months, 15-30 months, or >30 months post-treatment decreased from 0.28/month to 0.21/month to 0.15/month, respectively (P < 0.01). Milk-induced %CD63 and %CD203c expression was significantly lower in patients >24 months vs in patients <24 months post-treatment (P = 0.038 and P = 0.047, respectively). In conclusion, many patients experience mild adverse reactions after completing oral immunotherapy and some require injectable epinephrine. Progressive desensitization, both clinically and in basophil reactivity, occurs over time.

Anaphylaxis to celecoxib.

BACKGROUND: Adverse reactions such as urticaria, angioedema, asthma, and anaphylaxis are known to be associated with nonsteroidal anti-inflammatory agents (NSAIDs). Celecoxib (Pfizer/Searle, Caguas, PR) is a new NSAID that differs in structure and mechanism of action of other similar drugs of this class. OBJECTIVE: Evaluation of a case of anaphylaxis to celecoxib (Celebrex). METHODS AND RESULTS: This report describes a 55-year-old woman who experienced the acute onset of pruritus, urticaria, respiratory distress, and hypotension minutes after ingesting a celecoxib capsule. She had taken the drug a previous time for tendonitis without difficulty. Treatment with epinephrine, corticosteroids, and intravenous fluids was successful. An IgE mechanism could not be detected. She has avoided the drug and has had no further problems. CONCLUSIONS: This is the first patient report of anaphylaxis attributable to celecoxib, a new NSAID. This suggests that physicians and other health care professionals should be aware of the potential serious side effects of this drug.

Study of two controlled-release theophylline preparations.

Two sustained-release theophylline preparations, one a 12-hour and the other a 24-hour product, were compared in 20 subjects with stable asthma. All patients had good control of symptoms, and the calculated pharmacokinetic parameters were comparable for both drugs. The 24-hour sustained-release preparation can thus be utilized in the therapy of asthma.

Education and the decision to migrate: an econometric analysis of migration in Venezuela.

PIP: Interstate labor force migration in Venezuela was estimated for 3 groups of migrants classified by their own educational levels. Regional educational levels and education-specific average wages were included as explanatory variables in order to distinguish between the various effects of education on migration and to estimate differences in the response of educated and uneducated migrants to other explanatory variables. The basic model resembled that used in other econometric studies of migration; migration was assumed to be a function of a number of origin and destination state characteristics which were believed likely to represent costs and benefits of living in various states for most persons. Migration rates rather than absolute numbers were the dependent variable. Zellner's regression technique was employed, and appropriate F statistics were used to test the null hypothesis of equal response of migrants to each of the explanatory variables across educational levels. A substantial proportion of the variance in migration rates was explained for each level of education. The results showed that educated members of the labor force in Venezuela are more mobile and also that there are significant differences in the responses of educated and uneducated migrants to variables which reflect the costs and benefits of alternative locations. The educated were less deterred by increased distance and more responsive to wage rates in alternative locations. The educated appear to be more mobile because of their greater access to information and greater incentives to make additional investments in search of better opportunities. Both educated and uneducated migrants are attracted to more populated regions but the elasticity is almost twice as high for the educated. Educational opportunity was found to be an important locational advantage for those who already had attended secondary school. The less educated are less likely to move to states with high educational levels, perhaps because they fear job competition from the educated. Destination unemployment variables were not highly significant for the uneducated. Results of the study indicate that disaggregation of migration by educational levels is necessary for a clear understanding of the complex relationships involved.^ieng