Proven Food-Induced Acute Urticaria and Predictive Factors for Definitive Diagnosis in Childhood.

BACKGROUND: Urticaria can be the only sign of a food allergy or can be seen together with other signs and symptoms of a food allergy. OBJECTIVE: To determine the demographic, etiologic, and clinical features of food-induced acute urticaria in childhood. METHODS: Patients suspected of food-induced acute urticaria were included in this prospective cross-sectional multicenter study. RESULTS: Two hundred twenty-nine urticaria cases were included in this study. Seventeen patients who did not meet the inclusion criteria of the study were excluded. Of the 212 included cases, 179 (84.4%) were diagnosed with definitive food-induced acute urticaria. The most common foods causing acute urticaria were cow's milk, hen's eggs, and nuts in 56.4, 35.2, and 19% of cases, respectively. The positive predictive value of a history of milk-induced acute urticaria together with a milk-specific IgE >5 kU/L for cow's milk-induced acute urticaria was 92% (95% CI: 81-96%). A history of cow's milk-induced and/or hen's egg-induced acute urticaria was consistent with a definitive diagnosis of food-induced urticaria (Chen's kappa: 0.664 and 0.627 for milk and eggs, respectively). Urticaria activity scores were higher in patients with food-induced acute urticaria (p = 0.002). CONCLUSION: Cow's milk, hen's eggs, and nuts were the most common allergens in the etiology of childhood food-induced acute urticaria. Although the urticaria activity score provides guidance for diagnosis, an oral food challenge is often essential for the definitive diagnosis of a patient with a history of food-induced acute urticaria.

A successful desensitization protocol for horse-derived antithymocyte globulin in severe aplastic anemia.

BACKGROUND: Horse antithymocyte globulin (h-ATG) (ATGAM(®) ) is the first choice of treatment in very severe patients with aplastic anemia who do not have any HLA matched sibling donor. h-ATG is a heterologous serum that may cause anaphylaxis. Alternative treatment strategies must be planned in case of hypersensitivity. Desensitization must be considered in patients without an alternative treatment of choice. We aimed to present the h-ATG desensitization protocol and consider its effectiveness in patients with aplastic anemia who are hypersensitized with h-ATG and do not have an alternative treatment of choice. METHODS: Skin prick tests were performed with non-diluted solution in eight very severe patients with aplastic anemia who are followed up in Ege University Children's Hospital. Although skin prick test was found negative in these eight patients, different dilution h-ATG intradermal tests were performed and found positive in all patients. h-ATG desensitization program was started to these hypersensitized patients. RESULTS: Desensitization program was started to six male and two female very severe patients with aplastic anemia whose ages were between seven and 19 yr (median: 12.9 yr). All of the patients completed the desensitization program. While local reaction was seen in two patients, systemic reaction was seen in one patient and late reaction was seen in one patient during and after desensitization program. CONCLUSION: A successful desensitization program with h-ATG in children with aplastic anemia is presented. Even though there is not an exposure before to such high allergy potential heterologous serum, skin tests should be performed and desensitization must be started to patients who are hypersensitized to h-ATG. As the expected effectiveness of the treatment is so much, the desensitization protocol can be carried out safely and effectively with trained stuff although allergic reactions can be seen.

Could Age and Oral Challenge Outcomes Identify High-Risk Patients During Cow's Milk Oral Immunotherapy?

Objective: Severe immunglobuline E (IgE)-mediated reactions during oral immunotherapy (OIT) are major obstacles to treatment. The present study aimed to evaluate and identify clinical and laboratory biomarkers of adverse events during OIT among children with cow's milk (CM) allergy. Study Design: Eighty-six children older than 36 months who had undergone OIT with milk were enrolled. Clinical data, oral food challenge (OFC) test results, and laboratory data were recorded retrospectively. Results: The median duration of the build-up phase of OIT was 19 weeks (min 10-max 40) and the duration of the maintenance phase was 86.5 (min 1-max 132) months. A total of 11,767 CM doses were administered during the build-up phase and adverse reactions were seen in 62 (73.8%) patients with reactions registered for 157 doses among 11,767 (1/75 doses). The number of reactions during the maintenance phase was 41 (47.6%) in 24 (27.9%) patients. There was a significant reduction in the number of reactions (P = 0.000) between the build-up phase and maintenance phase. Adverse reactions and anaphylaxis were higher for patients who had cough during OFC (P = 0.003, P = 0.002, respectively) during the build-up phase and also during the maintenance phase too (P = 0.000). Evaluation for all reactions and anaphylaxis (during build-up and maintenance) with Kaplan-Meier and Cox regression analysis showed class IV-VI of CM-specific immunoglobulin E (sIgE), casein-sIgE and cough during OFC were significantly associated with increased probability of reaction and anaphylaxis. Younger age at onset of OIT was associated with risk reduction (0.017). Conclusion: Laboratory data and reactions during the OFC (especially cough) can help to identify high-risk patients during OIT.

Cut-Off Values of Specific IgE and Skin Prick Test to Predict Oral Food Challenge Positivity in Children with Cow's Milk Allergy.

OBJECTIVE: The cut-off values for the skin prick test diameters and cow's milk-specific IgE measurements are used to predict the result of the oral food challenge test for the diagnosis of cow's milk allergy. This study aimed to determine the diagnostic values of skin prick test and cow's milk-specific IgE according to age groups and compare the diagnostic powers of these 2 methods. MATERIALS AND METHODS: In total, 153 children who had a preliminary diagnosis of cow's milk allergy were evaluated. Group A (n = 90) consisted of cow's milk allergy patients whose diagnosis was confirmed by a positive oral food challenge or a history of anaphylaxis. Group B (n = 63) was composed of patients with a negative oral food challenge. The demographic, clinical, and laboratory findings of 2 groups were compared. RESULTS: The cut-off points for cow's milk-specific IgE and cow's milk-skin prick test were determined as >2.12 kUA/L and >5 mm, respectively. The area under the curve was 0.844 for cow's milk-skin prick test (sensitivity 73%, specificity 84%) and 0.745 for cow's milk-specific IgE (sensitivity 67%, specificity 86%). The diagnostic power of skin prick test was determined to be higher when compared to cow's milk-specific IgE (P = .02). According to the predicted probability curves, decision points for cow's milk-specific IgE and cow's milk-skin prick test with 95% probability were determined as follows, respectively: for ≤24 months: 22 kUA/L, 11.3 mm; for >24 months: 44.1 kUA/, 15.1 mm. The lowest cut-off value with a positive predictive value of 95% and a specificity of 96% was found in patients 3.3 kUA/L) Conclusion: The use of high probability diagnostic values of communities for specific IgE and skin prick test along with a significant clinical history may provide accurate and rapid diagnosis of cow's milk allergy and facilitate patient follow-up.

Oral Immunotherapy for Cow's Milk Allergy: Five Years' Experience from a Single Center in Turkey

Background: Oral immunotherapy for cow's milk allergy is an effective treatment option because of its ability to increase the threshold for clinical reactions. Aims: To present our experience of oral immunotherapy for cow's milk allergy in the pediatric allergy outpatient clinic, and to evaluate the long-term efficacy of oral immunotherapy and risk factors for adverse reactions during oral immunotherapy. Study Design: Single-center retrospective cohort study. Methods: Forty-two patients with Immunoglobulin-E-mediated cow's milk allergy who complied with the oral immunotherapy protocol were evaluated in this study. The treatment consisted of a rapid escalation phase with an oral food challenge step that included milk doses. During the build-up phase, increasing quantities of cow's milk were administered until the patient was able to consume 200 mL of cow's milk daily. Results: The mean age of starting the oral immunotherapy was 40.2±3.2 (range, 36-156) months, and 54.8% (n=23) of the patients were males. The mean duration of the build-up phase was 18.1±5.6 (range, 9-41) weeks, and the mean maintenance phase was 29.1±11.6 (range, 12-63) months. During the oral immunotherapy, 36 adverse reactions (78% mild and 22% moderate) occurred in 16 (38%) patients. There were no differences in the age of starting the oral immunotherapy (p=0.19), cow's milk-specific Immunoglobulin-E levels (p=0.17), and cumulative provocative doses of oral food challenges (p=0.78) between the two groups of patients with and without adverse reactions. The wheal diameters to cow's milk were higher in the group with adverse reactions (p=0.03). There was no difference in the oral immunotherapy onset age between patients with and without a history of anaphylaxis (p=0.38). The patients with a history of anaphylaxis had more adverse reactions (p=0.04) and a higher number of reactions during the oral immunotherapy (p=0.01), and a higher mean duration of the up-dosing phase (p=0.04) compared with patients without anaphylaxis. Conclusion: Oral immunotherapy is a treatment option in patients with cow's milk allergy because of its high efficacy. Adverse reactions occur in about 40% of cases and are mostly mild. It should be administered with caution to patients with a history of anaphylaxis and a higher wheal diameter to cow's milk in the skin prick test.

Successful Desensitization Protocol in an Infant Following Anaphylaxis Secondary to Recombinant Factor VIIa.

Background: Recombinant factor VIIa (rFVIIa) is a highly purified recombinant protein. It is approved for the treatment and prevention of bleeding episodes associated with congenital factor VII deficiency, congenital hemophilia with inhibitors, and Glanzmann's thrombasthenia. The most commonly reported adverse events are thrombolytic in nature. In this report, we present a successful desensitization protocol administered to an infant with a history of anaphylaxis to rFVIIa. Case: A male infant with a history of gingival bleeding at the age of 6 months was diagnosed with factor VII deficiency with a factor VII level of 1%. His sister also had diagnosis of factor VII deficiency. Our patient was hospitalized at 10 months of age with generalized petechiae and bloody stools. Twenty minutes after administration of rFVIIa, he developed anaphylaxis that responded to epinephrine and supportive care. Subsequently he was evaluated at the allergy clinic, where a skin prick test with rFVIIa was negative. However, the intradermal skin test, applied with 1/1,000 (1 µg/1 mL, 0.1 mL) dilution of rFVIIa, showed induration of 8 mm (positive reaction). Because there is no alternative treatment for factor VII deficiency, we developed a successful 13-step desensitization protocol with rFVIIa (NovoSeven®). Desensitization was performed an additional 2 times using the same protocol, one of which was for a head injury and the other for a swollen knee since the period between the doses was ∼3 months. Conclusion: Allergic reactions, such as anaphylaxis can occur without prior exposure. This can be due to the high molecular weight and structural property of the biological agent. In this report, we present an effective desensitization protocol for an infant with a history of anaphylaxis to rFVIIa. Desensitization protocols in this age group should be carried out in a medical facility and with specialized staff and equipment prepared to care for anaphylaxis.