Disparities in rate, triggers, and management in pediatric and adult cases of suspected drug-induced anaphylaxis in Canada.

INTRODUCTION: Data is sparse on drug-induced anaphylaxis (DIA) and there have not been studies assessing the differences in clinical characteristics and management of DIA between adults and children. OBJECTIVE: We assessed the percentage, diagnosis, and management of DIA among all anaphylaxis visits in three pediatric and one adult emergency departments (ED) across Canada. METHODS: Children presenting to the Montreal Children's Hospital (MCH), British Columbia Children's Hospital (BCCH), and Children's Hospital at London Health Sciences Center and adults presenting to Hôpital du Sacré-Coeur with anaphylaxis were recruited as part of the Cross-Canada Anaphylaxis Registry. A standardized data form documenting the reaction and management was completed and patients were followed annually to determine assessment by allergist and use of confirmatory tests. RESULTS: From June 2012 to May 2016, 51 children were recruited from the pediatric centers and 64 adults from the adult center with drug-induced anaphyalxis. More than half the cases were prospectively recruited. The percentage of DIA among all cases of anaphylaxis was similar in all three pediatric centers but higher in the adult center in Montreal. Most reactions in children were triggered by non-antibiotic drugs, and in adults, by antibiotics. The majority of adults and a third of children did not see an allergist after the initial reaction. In those that did see an allergist, diagnosis was established by either a skin test or an oral challenge in less than 20% of cases. CONCLUSIONS: Our results reveal disparities in rate, culprit, and management of DIA in children versus adults. Further, most cases of suspected drug allergy are not appropriately diagnosed. Guidelines to improve assessment and diagnosis of DIA are required.

Intranasal midazolam for seizure cessation in the community setting.

QUESTION: There are times when parents arrive to my clinic after their child has had a seizure and a second seizure takes place in the clinic. While waiting for transport to the hospital, are there ways to stop the seizures without the need to obtain intravenous access in the clinic? ANSWER: Intravenous diazepam has been a first-line therapy to stop seizures in children for many years. Other routes of drug administration such as intramuscular, rectal, and buccal are available but have several limitations. More evidence suggests that the intranasal route to administer drugs is quick and effective in children, and the use of midazolam has been continuing to show promise in seizure cessation. With its good safety profile, intranasal midazolam can be used in the clinic and prehospital setting for seizure cessation in children.

Omega-3 and dyslexia: Uncertain connection.

QUESTION: In light of the increase in the number of school-aged children diagnosed with dyslexia, what is the role of omega-3 supplements in the management of this condition? ANSWER: Dyslexia is the most common learning disability and is known to have multifactorial causes. Recent evidence suggests that there is a connection between defects in highly unsaturated fatty acid metabolism and neurodevelopmental disorders such as dyslexia. While the benefit of omega-3 supplementation for children with dyslexia has been studied, evidence remains limited. Unified diagnostic criteria for dyslexia, objective measures of fatty acid deficiency, and close monitoring of dietary intake are some of the factors that would improve the quality of research in the field.

Patch use in time and space for a meso-predator in a risky world.

Predator-prey studies often assume a three trophic level system where predators forage free from any risk of predation. Since meso-predators themselves are also prospective prey, they too need to trade-off between food and safety. We applied foraging theory to study patch use and habitat selection by a meso-predator, the red fox. We present evidence that foxes use a quitting harvest rate rule when deciding whether or not to abandon a foraging patch, and experience diminishing returns when foraging from a depletable food patch. Furthermore, our data suggest that patch use decisions of red foxes are influenced not just by the availability of food, but also by their perceived risk of predation. Fox behavior was affected by moonlight, with foxes depleting food resources more thoroughly (lower giving-up density) on darker nights compared to moonlit nights. Foxes reduced risk from hyenas by being more active where and when hyena activity was low. While hyenas were least active during moon, and most active during full moon nights, the reverse was true for foxes. Foxes showed twice as much activity during new moon compared to full moon nights, suggesting different costs of predation. Interestingly, resources in patches with cues of another predator (scat of wolf) were depleted to significantly lower levels compared to patches without. Our results emphasize the need for considering risk of predation for intermediate predators, and also shows how patch use theory and experimental food patches can be used for a predator. Taken together, these results may help us better understand trophic interactions.