Revaccination outcomes among adolescents and adults with suspected hypersensitivity reactions following COVID-19 vaccination: A Canadian immunization research network study.

Background: COVID-19 vaccination has been associated with anaphylaxis and hypersensitivity reactions. Infectious disease physicians and allergists in the Canadian Special Immunization Clinic (SIC) Network developed guidance for evaluating patients with adverse events following immunization (AEFI) including suspected hypersensitivity. This study evaluated management and adverse event recurrence following subsequent COVID-19 vaccinations.

Safety of Direct Drug Provocation for the Evaluation of Penicillin Allergy in Low-Risk Adults.

Background: About 10% of patients have a penicillin allergy label, but less than 5% of them are actually allergic. Unnecessary penicillin avoidance is associated with serious medical consequences. Given the growing number of these labels, it is imperative that our diagnostic strategy for penicillin allergy be as efficient as possible.

Tolerability of sublingual versus vestibular allergy immunotherapy tablet administration: A randomized pilot study.

Background: Local application site reactions are common with sublingual allergy immunotherapy (AIT)-tablets for the treatment of allergic rhinitis/conjunctivitis (AR/C) and occasionally lead to treatment discontinuation. Because of the lower mast cell density in the vestibular mucosa than the sublingual area, vestibular AIT-tablet administration may result in fewer adverse events (AEs). This pilot study evaluated the tolerability of the vestibular administration route of AIT-tablets compared with the sublingual route in adult subjects with AR/C.

Rate of Recurrence of Adverse Events Following Immunization: Results of 19 Years of Surveillance In Quebec, Canada.

Background: While adverse events following immunization (AEFI) are frequent, there are limited data on the safety of reimmunizing patients who had a prior AEFI. Our objective was to estimate the rate and severity of AEFI recurrences.

Methods: We analyzed data from the AEFI passive surveillance system in Quebec, Canada, that collects information on reimmunization of patients who had a prior AEFI.

Clinical Approach Used in Medical Consultations for Allergic-Like Events Following Immunization: Case Series Report in Relation to Practice Guidelines.

Background: The Joint Task Force on Practice Parameters (JTFPP) guidelines for the investigation and reimmunization of patients who experienced allergic-like events (ALEs) after immunization are predicated on the likelihood of anaphylaxis, assessed through the time to symptom onset (≤ or >4 hours) and number of systems involved.

Objective: The objectives of this study were to compare the management of a series of patients with ALE in actual practice relative to JTFPP guidelines and to discuss key concepts and considerations in their use.

Methods: This retrospective study was based on a chart review of patients who consulted for suspected vaccine-associated ALEs at a large allergy department in Canada.

Thalidomide in Refractory Tuberculomas and Pseudoabscesses.

Paradoxical immune reconstitution inflammatory syndrome is a well-described entity even in immunocompetent children, principally in association with Mycobacterium tuberculosis infections. Central nervous system involvement is a potential life-threatening form, sometimes refractory to standard treatment. We report the case of an HIV-negative refugee teenager, who presented with brain tuberculomas and pseudoabscesses responsive only to thalidomide.

Distance to faults as a proxy for radon gas concentration in dwellings.

This research was done to demonstrate the usefulness of the local structural geology characteristics to predict indoor radon concentrations. The presence of geologic faults near dwellings increases the vulnerability of the dwellings to elevated indoor radon by providing favorable pathways from the source uranium-rich bedrock units to the surface. Kruskal-Wallis one-way analyses of variance by ranks were used to determine the distance where faults have statistically significant influence on indoor radon concentrations.

Methodology developed to make the Quebec indoor radon potential map.

This paper presents a relevant approach to predict the indoor radon potential based on the combination of the radiogeochemical data and the indoor radon measurements in the Quebec province territory (Canada). The Quebec ministry of health asked for such a map to identify the radon-prone areas to manage the risk for the population related to indoor radon exposure. Three radiogeochemical criteria including (1) equivalent uranium (eU) concentration from airborne surface gamma-ray surveys, (2) uranium concentration measurements in sediments, (3) bedrock and surficial geology were combined with 3082 basement radon concentration measurements to identify the radon-prone areas.

An approach to define potential radon emission level maps using indoor radon concentration measurements and radiogeochemical data positive proportion relationships.

The aim of this paper is to present the first step of a new approach to make a map of radonprone areas showing different potential radon emission levels in the Quebec province. This map is a tool intended to assist the Quebec government in identifying populations with a higher risk of indoor radon gas exposure. This map of radon-prone areas used available radiogeochemical information for the province of Quebec: (1) Equivalent uranium (eU) concentration from airborne surface gamma-ray surveys; (2) uranium concentration measurements in sediments; and (3) bedrock and surficial geology.

Multicentric castleman disease in a child with primary immunodeficiency.

Multicentric Castleman disease is a rare lymphoproliferative disorder mostly seen in adults with HIV. It presents with fever and systemic symptoms and is extremely uncommon in children. We describe a novel case of multicentric Castleman disease associated with primary immunodeficiency (common variable immunodeficiency) and discuss pathophysiologic mechanisms and recent advances in understanding this disease.