Drug fever-an immune-mediated delayed type hypersensitivity reaction to Vinca alkaloids in pediatric oncology patients, possibly mediated by cysteinyl leukotrienes.

Background: Drug hypersensitivity reactions are common in pediatric hemato-oncology patients due to multiple factors including immune compromise and pharmacological complexities. Fever can signify severe delayed-type hypersensitivity reactions such as drug reaction with eosinophilia and systemic symptoms (DRESS) or drug-induced hypersensitivity syndrome (DIHS). The etiology of fever as an isolated hypersensitivity reaction to chemotherapeutic agents not fully understood. Here, we report three children with intracranial neoplasms experiencing recurrent febrile reactions following Vinca alkaloid-based chemotherapy, mitigated by cysteinyl leukotriene receptor antagonist therapy. Methods: We present a series of pediatric patients with diverse intracranial neoplasms who developed recurrent fever episodes after multiple courses of Vinca alkaloid-based chemotherapy. Treatment involved prophylactic and post-chemotherapy administration of a cysteinyl leukotriene receptor antagonist to prevent fever episodes and enable completion of chemotherapy regimens without protocol modifications or desensitization. Results: All three patients experienced fever consistent with delayed-type hypersensitivity reactions to Vinca alkaloids. Prophylactic use of the leukotriene antagonist Montelukast successfully prevented fever recurrence, allowing uninterrupted completion of chemotherapy courses. Conclusion: Our findings suggest that Montelukast, a leukotriene antagonist, may be beneficial in managing fever as a delayed-type hypersensitivity reaction to Vinca alkaloids in pediatric patients. Further research is warranted to elucidate the underlying mechanisms and leukotriene pathways involved in drug-induced fever reactions.

Peanut oral immunotherapy using an extensively heated and baked novel composition of peanuts.

BACKGROUND: Oral immunotherapy (OIT) is an increasingly acceptable therapeutic option for peanut-allergic (PA) children, despite significant side effects. Major peanut allergenic proteins are heat-resistant and are not rendered hypoallergenic after baking or cooking. Lyophilized peanut protein-MH (LPP-MH) is a novel composition from developing peanuts, enabling cooking-induced reduction in allergenicity. We aimed to explore the safety and efficacy of OIT, with extensively heated and baked (EHEB) LPP-MH in PA children. METHODS: In a single-arm, single-center, pilot study, PA children with a single highest tolerated dose of <100 mg peanut protein were placed on a 40-week OIT protocol with 300 mg daily of heat-treated LPP-MH. A repeat open peanut food challenge was performed after 40 weeks of treatment and at a 6-12 months of follow-up visit. RESULTS: Thirty-three children with PA were enrolled, with a mean cumulative tolerated dose (MCTD) of 71.2 mg PP (95% CI 45-100 mg). After 40 weeks, 32/33 patients were able to consume more than 300 mg of natural PP, with MCTD of 1709 mg (CI 365-3675 mg). There were no severe allergic reactions requiring epinephrine, during any of the observed LPP-MH challenges or any treatment related doses at home. After 6-12 months on daily maintenance, the MCTD was 8821 mg (95% CI 1930-13,500 mg). This enabled most children age-appropriate dietary inclusion of peanuts. CONCLUSION: An OIT protocol with heat-treated LPP-MH, a novel composition from developing peanuts, seems a potentially safe and efficacious OIT modality for PA children, enabling the introduction of dietary levels of peanut proteins in highly allergic PA children. Validation in randomized controlled studies is mandated.

A clinical pathway for the diagnosis of sesame allergy in children.

Background: Sesame allergy (SA) is a common cause of life-threatening, persistent food allergy, not only in the Middle East and Asia, but increasingly worldwide. Commercially available tests such as extracts for skin testing or specific IgE for sesame or its components in serum, have very limited predictive values. Therefore the diagnosis is dependent on the performance of oral food challenges (OFC), frequently avoided in children, due to time and resource constraints, as well as the risk of anaphylaxis. In the current study we aimed to develop a simple, readily available, clinical tool, able to predict sesame OFC outcomes in children. Methods: Children with a history of SA were evaluated in the outpatient allergy clinic. All children underwent natural sesame OFC, with an additional baked-sesame challenge offered to children with SA. Clinical data were compared between the sesame tolerant (ST) and SA groups. Machine-learning tools were applied, to create a simple, clinically driven, decision tree analysis (DTA), predicting the outcome of sesame OFCs and the diagnosis of SA. Results: One hundred four children, mean age 47.2 months, 58% boys were included, with a high prevalence of additional food allergies, atopic dermatitis, asthma, and rhinitis. Following OFC, 56 (54%) were diagnosed as ST and 48 (46%) SA. Among SA children, 85% were able to consume baked-sesame in equal or higher protein amounts compared to natural sesame paste. Compared to ST, SA children had a tendency towards a higher incidence of allergic rhinitis (5% Vs 17%, p = 0.062), multiple food allergies (3.6% vs 12.5%, p = 0.09) and requiring medical treatment after the initial SA reaction (27% vs 41%, p = 0.022). As a group, skin tests with both commercial and natural tahini paste differed significantly between ST and SA (mean wheal in mm, for extract 4.2 vs 13.4, p < 0.001 and for natural sesame paste 6.7 vs 24.4, p < 0.001), However, the PPV of any individual test was only between 60%-85%. Our exploratory, clinical DTA, predicted OFC outcomes and the presence or absence of Sesame Allergy, with ≥96% positive (PPV) and negative (NPV) predictive values. Conclusion: OFCs remain the gold standard for the diagnosis of Sesame Allergy and are indicated to define ST/SA status even in highly atopic patients with previous immediate allergic reactions to sesame. A decision-tree analysis based on clinical parameters easily available in every allergy clinic, can predict the outcome of sesame OFC in the vast majority of children, increasing the safety and availability of such diagnostic procedures.

Oral immunotherapy for children with a high-threshold peanut allergy.

BACKGROUND: Between 25% and 30% of children with peanut allergy (PA) have a relatively high-threshold peanut allergy (HTPA), with a single maximal tolerated dose (SMTD) higher than 100 mg of peanut protein (PP). However, this threshold may decrease with time, age, exercise, illness, sleep deprivation, and other covariates. OBJECTIVE: To explore the feasibility of a simplified oral immunotherapy (OIT) protocol in a group of children with HTPA. METHODS: Children with PA with an SMTD higher than 100 mg were placed on a 40-week OIT protocol of either 300 mg/d of PP or 100 mg/d for 20 weeks followed by 300 mg/d for 20 weeks. A repeat open peanut food challenge was performed after 40 weeks of treatment and at a 6-month follow-up visit. After the 40-week challenge, all children received a maintenance dosage of 2 gPP 3 times a week. RESULTS: A total of 28 children with HTPA were enrolled, with 56% boys, 89% younger than 6 years old, and a mean SMTD of 304 mg (95% confidence interval 229-378). All were placed on the described OIT protocol. Overall, 2 children were not compliant and 3 had allergic reactions at home on the dose previously tolerated in clinic, 23 completed the 40-week protocol, and all were able to consume 2 g of PP. The mean tolerated dosage at the 6-month follow-up was 8 g. This enabled most children age-appropriate dietary inclusion of peanut-containing products. CONCLUSION: In children with HTPA, a simple, fixed-dose OIT can be both safe and efficacious.

Diagnosis of Peanut Allergy in Preschool Children: The Impact of Skin Testing With a Novel Composition of Peanuts.

Peanut allergy is an increasing concern in younger children. Available bedside diagnostic tools, i.e., prick tests with commercial extracts or peanut-containing foods have only limited predictive values. In a cohort of preschoolers with both a history of allergic reactions and sensitization to peanut proteins, we aimed to characterize the impact of skin tests with a novel composition of peanuts LPP-MH. Almost one quarter (27/110) of preschool children, with a history of allergic reactions to peanuts and positive standard IgE-mediated tests for peanut allergy, can tolerate the reintroduction of peanut proteins into their diet after resolving their allergy and, thus, can avoid adverse health outcomes associated with the false diagnosis. In the younger age group, a quarter of peanut allergic children, display a relatively high threshold, potentially enabling an easier and safer oral immunotherapy protocol in this window of opportunity in childhood. The use of the novel diagnostic skin test, LPP-MH, significantly improves the predictive value of outpatient evaluation for the outcomes of peanut challenge as well as the expected threshold at which the PA child will react, thus, making for a better informed decision of how, when, and where to challenge.

A structured graduated protocol with heat denatured eggs in the treatment of egg allergy.

BACKGROUND: Most children with egg allergy (EA) can tolerate extensively heated and baked egg (EHBE). Consumption of EHBE may promote faster resolution of EA; however, no consensus exists as to the required amounts and treatment protocols. OBJECTIVE: To evaluate the efficacy and safety of a structured graduated exposure protocol (SGEP) with EHBE in promoting tolerance to eggs in EA children under 2 years of age. METHODS: In a case-control study, EA children aged < 2 years who were treated with SGEP including EHBE were compared to children treated with strict avoidance. Data were collected from records and telephone questionnaires. Analysis was performed using non-parametric Kaplan-Meier and Cox proportional hazard regression models. RESULTS: Thirty-nine egg-allergic children with a median age at intervention of 16 months (interquartile range: 13-19) were treated with SGEP and followed to a median age of 39 months (26.8-50.0). The median age at resolution of EA was compared to a matched group of 80 children treated with strict avoidance at least until 2 years of age or earlier natural resolution and followed to a median age of 69 months (46-104). The median estimated age at EA resolution in the SGEP group was 24 months (95% CI, 19.5-28.5 months), compared to 78 months (95% CI, 53-102) in the control group, P < .001. At last follow-up, 82% of treated children were tolerant to lightly cooked eggs vs 54% of controls, P = .001. CONCLUSION: A structured protocol with EHBE appears to promote faster resolution of EA.

Controversies in Drug Allergy: Beta-Lactam Hypersensitivity Testing.

All beta-lactam use is associated with a certain rate of adverse reactions. Many of these adverse reactions result in an allergy to the beta-lactam being entered into the patient's medical record. Unfortunately, only a small minority of these recorded allergies are clinically significant immunologically mediated drug hypersensitivity. An unconfirmed allergy to beta-lactams is a significant public health risk, because patients so labeled typically do not receive narrow-spectrum penicillins and cephalosporins when clinically indicated. The alternative antibiotics they receive result in poorer clinical outcomes, increased incidence of serious antibiotic-resistant infections, prolonged hospitalizations, and greater health care utilization. There is a wide variation in beta-lactam allergy incidence and prevalence around the world, based in part on the specific beta-lactams used and overused. There is a wide variation in specific protocols used to confirm current tolerance of beta-lactams and remove these inaccurate allergy reports. Harmonizing testing protocols, when possible, may lead to more widespread use of narrow-spectrum beta-lactams, when clinically indicated, and improve patient safety worldwide. Further research is needed to better understand the regional differences in reporting beta-lactam allergy as this relates to regional differences in beta-lactam use and overuse, the frequency of clinically significant immunologically mediated beta-lactam hypersensitivity, and the optimal testing strategies to confirm current tolerance, based on presenting clinical symptoms.

A Structured Gradual Exposure Protocol to Baked and Heated Milk in the Treatment of Milk Allergy.

OBJECTIVE: To evaluate the efficacy and safety of a structured gradual exposure protocol (SGEP) with extensively heated and baked milk in promoting allergy resolution in children with cow milk allergy (CMA). STUDY DESIGN: In a case control study, children with CMA aged 1-4 years who were treated with SGEP including extensively heated and baked milk, were compared with children treated with strict avoidance. Data were collected from medical records and from validated telephone questionnaires. Data analysis was performed using a nonparametric Kaplan-Meier and proportional hazard Cox regression model, after evaluation of the adequacy of the case control matching. RESULTS: There were 43 children with milk allergy-26 (62%) males with a mean age at intervention of 21 months (range, 12-47 months)-who were treated with SGEP and followed to a mean age of 40 months (range, 20-82 months). The median age at resolution of CMA was compared with a matched group of 67 children treated with strict avoidance at least until 4 years of age or followed until earlier resolution, with a mean age at follow-up of 71 months (range, 11-176 months). The median estimated age at CMA resolution in the SGEP group was 36 months (95% CI, 34.5-49.7) compared with 98 months (95% CI, 82.4-114.1) in controls (P < .001). At last follow-up, 86% of treated children were tolerant to unheated milk proteins vs 52% of controls (P = .003). CONCLUSION: A structured protocol with extensively heated and baked milk seems to promote faster resolution of CMA.

Mite component-specific IgE repertoire and phenotypes of allergic disease in childhood: the tropical perspective.

Sensitization to perennial aeroallergens correlates with the risk of persistent asthma (AS) in children. In tropical Singapore, multiple codominant species of mites abound in the indoor environment, and preferential species-specific sensitization has been associated with different phenotypes of allergic disease. We investigated the pattern of mite component-specific IgE (mcsIgE) in children with different phenotypes of clinical allergic disease in an environment with multiple mite species exposure. A prospective evaluation of newly diagnosed patients with clinical diagnosis of allergic rhinitis (AR), atopic dermatitis (AD), or AS and sensitization to one or more aeroallergens were performed. Sera were tested for specific IgE against an extensive panel of Dermatophagoides pteronyssinus and Blomia tropicalis allergens. A total of 253 children were included, mean age 7.3 yr, 79% fulfilled criteria for AR, 46% AS, 71% AD, and 31% for all three. Sensitization to one or both mites was observed in 91% of children, 89% were sensitized to D. pteronyssinus, and 70% to B. tropicalis. The most common mite allergens recognized by these atopic children were Der p 1 (64%), Der p 2 (71%), Blo t 5 (45%), Blo t 7 (44%), and Blo t 21 (56%). Specific IgE responses to an increased number of distinct mite allergens correlated with the complexity of the allergic phenotype. In multivariate analysis, an increased risk for the multi-systemic phenotype (AR + AS + AD) was associated with sensitization to an increased repertoire of mite components (three or more) (OR 4.3, 95% CI 2.1-8.8, p = 0.001) and a positive parental history of AS (OR 2.4, 95% CI 1.2-2.9, p = 0.013). A highly pleiomorphic IgE response to the prevalent indoor mites is associated with the presence of a multi-systemic allergic phenotype in childhood in a tropical environment.

Pulmonary function correlates with arterial stiffness in asthmatic patients.

BACKGROUND: At the population level, asthma has been associated with chronic systemic inflammation as well as adverse cardiovascular outcomes. OBJECTIVES: The aim of this study was to investigate peripheral vascular hemodynamic variables of arterial stiffness (AS) and their relationship to pulmonary function tests in asthmatic patients. METHODS: Young asthmatic patients from the tertiary center for pulmonary diseases at the Barzilai Medical Center underwent pulmonary function evaluation and non-invasive radial artery hemodynamic profiling, pre- and post-exercise. Results were compared to age matched, non-asthmatic controls. RESULTS: 23 young asthmatics and 41 controls, completed all evaluation points. Pulmonary flow parameters were significantly reduced in the asthma group at all points. There were no differences between groups in BMI, blood pressure, pulse rate or measurements of AS at baseline or after bronchodilation. The % predicted forced expiratory volume in the first second at baseline (FEV1%) in asthmatics was positively correlated with the small arteries elasticity index (SAEI) and negatively correlated with the systemic vascular resistance (SVR) in these patients. These correlations were not observed in non-asthmatic controls. In multifactorial regression FEV1 remained the major factor associated with measurements of AS in asthmatic patients, while gender was the only significant factor in non-asthmatic controls. CONCLUSIONS: Significant correlations between measurements of AS and FEV1 in young asthmatics, suggest the presence of a common systemic, most likely inflammatory pathway involving both the cardiovascular and respiratory systems.

Impact of specific allergen sensitization on the prevalence of asthma in patients with allergic rhinitis from adjacent distinct geographic areas.

BACKGROUND: Patients with allergic rhinitis (AR) and perennial allergen sensitization are at increased risk for asthma. OBJECTIVES: To determine the allergic profile of patients with clinical AR in regions of the coastal Mediterranean compared with the inland southern desert area of Israel and the impact of specific allergen sensitization on the prevalence of asthma in these patients. METHODS: Retrospective evaluation of medical records from patients referred for evaluation during 2002 and 2003 to the allergy clinics of 3 medical centers located in different geoclimatic areas. RESULTS: A total of 479 patients with AR were included (64% from the humid Mediterranean coast and 36% from the arid desert area), with a mean age of 32.8 years (range, 6-84 years). Sixty percent of the patients were male, and 33% had an additional diagnosis of asthma. Mite sensitization was 84%; cockroach, 34%; trees, 43%; weeds, 40%; grasses, 53%; and fungi, 30%. There were no significant differences in the prevalence of sensitization to any of the evaluated allergens except for weeds, which was higher in the arid region. A diagnosis of asthma was significantly associated with mite sensitization in the Mediterranean area (odds ratio, 2.24; 95% confidence interval, 1.14-4.4; P = .02) and mold sensitization in the arid climate zone (odds ratio, 2.18; 95% confidence interval, 1.05-4.6; P = .04). CONCLUSION: Although sensitization to mites is high in the coastal areas and in the Negev desert-like environment, the presence of asthma in patients with AR is associated with mite sensitization in the humid environment but with fungal sensitization in the more arid environment.

Safety and efficacy of allergen immunotherapy in the treatment of allergic rhinitis and asthma in real life.

BACKGROUND: Subcutaneous allergen immunotherapy is effective in treating allergic airway disease. Disadvantages include immediate local and systemic adverse reactions and poor compliance. OBJECTIVES: To obtain real-life efficacy and safety data through a prospective observational study of SIT in the allergist's office. METHODS: We prospectively collected data from all patients with a diagnosis of allergic rhinitis and/or asthma and a specific immunoglobulin E-mediated sensitization to one or more aeroallergens who began SIT during the 2 year period 1 January 2005 to 31 December 2006. As part of the routine immunotherapy care patients were asked to complete a disease activity questionnaire before and yearly during the treatment. The primary outcome measure was the combined rhinitis and asthma symptoms scores. Data from patients completing at least 1 year of immunotherapy were analyzed. RESULTS: Altogether, 133 enrolled patients with a mean age of 22.7 years completed at least 1 year of SIT. The allergic rhinitis and asthma disease activity score decreased from a mean of 8.1 to 3.3 (rhinitis) and from 4.8 to 2.4 (asthma) on a 10 cm visual analogue scale after 1 year of SIT (P < 0.001 for all comparisons). Rhinitis medication use in all patients and asthma medication use in asthmatics decreased significantly. Mild local adverse reactions were almost universal. There were 11 patients (8%) who developed 14 immediate systemic, mild to moderate reactions. All reactions were successfully treated in the clinic; none required additional observation or hospitalization. CONCLUSIONS: In the hands of experienced allergists subcutaneous allergy immunotherapy is a safe and efficacious option for patients with allergic rhinitis and asthma.