Food reactions during avoidance: Focus on peanut.

OBJECTIVE: Peanut allergy has historically been difficult to manage, with most cases persisting into adulthood. Novel therapies for peanut allergy treatment are on the horizon, yet allergists must maintain a robust understanding of the risks and benefits of the current standard of therapy, avoidance diet. DATA SOURCES: A comprehensive literature search using PubMed of reviews and clinical articles was performed. STUDY SELECTIONS: Articles discussing peanut or other food-related allergic reactions, accidental exposures or anaphylaxis pertinent to avoidance diet or comparative to oral immunotherapy trials were selected. RESULTS: Peanut remains a leading allergen associated with accidental ingestions responsible for food-related reactions, both mild and severe. Fatal reactions, however, are rare and measures such as anaphylaxis plans can significantly decrease the risk of accidental anaphylaxis. Patients may over estimate situations thought to increase risk for reactions to peanut, such as inhalation or contact through skin. In oral immunotherapy trials, the rate of anaphylaxis secondary to treatment was significantly higher than avoidance practices. CONCLUSION: Clinicians should continue to discuss avoidance as a viable option for long-term peanut allergy management and empower patients to differentiate relevant situations in which accidental reactions might occur.

Immediate hypersensitivity reaction to human serum albumin in a child undergoing plasmapheresis.

BACKGROUND: Human serum albumin (HSA) is a commonly used colloid for volume expansion and albumin replacement and during plasmapheresis. Colloids are an uncommon cause of anaphylaxis, and cases of hypersensitivity reactions to HSA are extremely rare. CASE REPORT: A 10-year-old boy with chronic inflammatory demyelinating polyneuropathy was treated with plasmapheresis, with albumin as the replacement fluid. He developed a severe reaction characterized by respiratory, gastrointestinal, and cutaneous symptoms. RESULTS: Skin testing to HSA was positive and resulted in objective systemic symptoms, suggesting an immediate hypersensitivity reaction to HSA. CONCLUSION: While colloids are an uncommon cause of immediate hypersensitivity reactions, they can lead to severe and potentially fatal reactions if not recognized and treated promptly.

Efficacy and safety of omalizumab in pediatric patients with high immunoglobulin E levels: A case series.

BACKGROUND: The efficacy and safety of omalizumab has been demonstrated in children as young as 6 years of age. Omalizumab is currently approved for a range of immunoglobulin E (IgE) levels that differ by age. In patients with IgE levels higher than the indicated therapeutic window, only a few studies have demonstrated the efficacy and safety of its use. Specifically, no reported studies exist to describe the use of omalizumab in pediatric patients with asthma ages <12 years and with high IgE levels. OBJECTIVE: We reported a series of pediatric patients who were initiated on omalizumab despite an IgE level higher than the age-indicated therapeutic windows and aimed to describe whether omalizumab was safe and improved asthma outcomes. METHODS: Patients who initiated omalizumab in our pediatric allergy clinic between January 2008 and December 2015, with serum IgE levels higher than the age-indicated therapeutic ranges were included. Patient charts were reviewed to determine the number of asthma-related events in the 12 months before and after initiation of omalizumab and the Asthma Control Test™ scores at the time of initiation and at 12 months of therapy. RESULTS: Eleven patients were identified with pretreatment IgE levels higher than the age-approved thresholds. Five patients were ages <12 years, and six patients were ages >12 years. For all but one patient, the maximum recommended dose of 375 mg every 2 weeks was effective in reducing the need for corticosteroids, emergency department visits, or hospitalizations in the year after initiation of therapy. During the period of therapy, there were no reports of severe reactions. CONCLUSION: Despite a small study group, our results indicated that omalizumab may be safely used in pediatric patients with IgE levels higher than the indicated therapeutic windows.

Elevated Atopic Comorbidity in Patients with Food Protein-Induced Enterocolitis.

BACKGROUND: Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy. Its relationship to the major atopic manifestations (atopic dermatitis [AD], IgE-mediated food allergy [IgE-FA], allergic rhinitis [AR], asthma) is not understood. OBJECTIVE: To determine the clinical characteristics, epidemiologic features, and natural history of FPIES in relation to the major atopic manifestations. METHODS: We examined our primary care birth cohort of 158,510 pediatric patients, of whom 214 patients met 2017 FPIES diagnostic criteria. We measured the influence of FPIES on developing subsequent atopic disease. RESULTS: Pediatric FPIES incidence was between 0.17% and 0.42% depending on birth year. As in prior reports, most patients had an acute presentation (78%), and milk, soy, oat, rice, potato, and egg were common triggers. The mean age of diagnosis was 6.8 months. Atopic comorbidity was higher in patients with FPIES compared with healthy children (AD, 20.6% vs 11.7%; IgE-FA, 23.8% vs 4.0%; asthma, 26.6% vs 18.4%; AR, 28.0% vs 16.7%; P < .001 χ2). However, longitudinal analyses indicated that prior FPIES did not influence the rate of atopy development. CONCLUSIONS: The incidence of FPIES in our cohort was initially low, but is increasing. Food allergen distribution, presentation, and age of onset are similar to prior reports. Patients with FPIES have high rates of atopic comorbidity. However, longitudinal analysis does not support direct causation as the etiology of these associations. Rather it suggests a shared predisposition to both types of allergy, or associative bias effects. This work refines our understanding of the natural history of FPIES by elucidating associations between FPIES and atopy.

Food Protein-Induced Enterocolitis Syndrome Food Challenges: Experience from a Large Referral Center.

BACKGROUND: Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy that is diagnosed based on clinical findings, but can be confirmed with oral food challenge (OFC). OFC is more often performed to assess the development of tolerance. Most studies describing OFCs in FPIES are limited in size. OBJECTIVE: We sought to describe our experience with OFCs using our FPIES protocol. Patients were given one-third of serving size with a 4-hour observation period, followed by home titration to full dose. METHODS: We conducted a retrospective chart review of patients who underwent OFC via the FPIES protocol from 2014 to 2017. Data regarding the history of reaction, age at the time of challenge, and reactions during challenge or with home introduction were collected. RESULTS: A total of 169 OFCs were completed under the FPIES protocol, in 119 patients to 19 different foods. Thirty challenges (18%) were positive, with 17 challenges (10%) during initial challenge and 13 (7.7%) during home dosing. Most reactions during initial challenge required intravenous fluids (IVF), but hypotension was uncommon. One hundred thirty-nine (82%) OFCs were negative with home introduction, indicating tolerance to the challenged foods. The mean age of passing a challenge to milk, soy, and grain was earlier than that of other solid foods. CONCLUSIONS: Our data suggest that our FPIES OFC protocol is safe. Early administration of IVF may prevent the development of hypotension. It is difficult to stratify the risk of severe or delayed reaction based on patient characteristics, and more data are needed to identify those appropriate for home introduction.

Comparative analysis of different approaches to measure treatment response in acute myeloid leukemia.

PURPOSE: In acute myeloid leukemia (AML), initial treatment response by morphologic analysis of bone marrow predicts long-term outcome. Response can now be assessed by minimal residual disease (MRD) monitoring with flow cytometry or polymerase chain reaction (PCR). We determined the relation among the results of these approaches and their prognostic value. PATIENTS AND METHODS: In the multicenter AML02 study, follow-up bone marrow samples from 203 children and adolescents with newly diagnosed AML were examined by flow cytometry (n = 1,514), morphology (n = 1,382), and PCR amplification of fusion transcripts (n = 508). Results were correlated with treatment outcome. RESULTS: Among 1,215 samples with less than 5% leukemic myeloblasts by morphology, 100 (8.2%) were MRD positive (≥ 0.1%) by flow cytometry, whereas 96 (57.5%) of the 167 samples with ≥ 5% blasts were MRD negative. Virtually all (308 of 311; 99.0%) MRD-negative samples by PCR were also MRD negative by flow cytometry. However, only 19 (9.6%) of the 197 PCR-positive samples were flow cytometry positive, with analyses of AML1-ETO and CBFß-MYH11 accounting for most discrepancies, whereas eight of 13 MLL-positive samples had detectable MRD by flow cytometry. MRD by flow cytometry after induction 1 or 2 predicted lower event-free survival and higher relapse rate (P < .001) and was an independent prognostic factor in a multivariable analysis; prediction was not improved by morphologic information or molecular findings. CONCLUSION: In childhood AML, morphologic assessment of treatment response has limited value if MRD is measured by flow cytometry. MLL fusion transcripts can provide prognostic information in some patients, whereas monitoring of AML1-ETO and CBFß-MYH11 transcripts is largely uninformative.