Clinical outcomes and management of contrast hypersensitivity in patients requiring repeated computed tomography imaging.

Introduction: In collaboration with the Department of Rheumatology, Allergy and Immunology, our study aims to review the outcomes of and propose an improved workflow for the management of patients with prior hypersensitivity reactions to iodinated contrast media (ICM).

Method: Outpatients coming for contrast-enhanced computed tomography (CECT) were stratified into 3 categories (definite, unconfirmed and inaccurate) based on likelihood of their contrast hypersensitivity label. Patients could be offered a different ICM, receive the same ICM, or be referred to an allergist for further evaluation.

Evaluation of Patients with Vaccine Allergies Prior to mRNA-Based COVID-19 Vaccination.

During the initial rollout of coronavirus disease 2019 (COVID-19) vaccination in Singapore, the Ministry of Health (MOH) issued a recommendation that patients with a history of any previous vaccine allergy be referred to an allergist for further review of their suitability to proceed with mRNA-based COVID-19 vaccines. Patients fulfilling the above criterion were divided into three groups: immediate reaction (Group A), delayed reaction (Group B) and no/irrelevant reaction (Group C). They were subjected to either a skin prick test (SPT) and intradermal test (IDT) with polyethylene glycol (PEG) or polysorbate-containing products; direct injection with the Pfizer BNT162b2 vaccine in the allergy clinic; or injection at community vaccination centres, respectively.

Pseudo-Anaphylactic Reactions to Pfizer BNT162b2 Vaccine: Report of 3 Cases of Anaphylaxis Post Pfizer BNT162b2 Vaccination.

Anaphylactic reactions were observed after Singapore's national coronavirus disease 2019 (COVID-19) vaccination programme started in December 2020. We report the clinical and laboratory features of three patients in our institution who developed anaphylactic reactions after receiving the Pifzer BNT162b2 vaccine. IgM and IgG antibodies, but not IgE antibodies to the Pfizer BNT162b2 vaccine, were detected in all subjects.

Shellfish/crustacean oral allergy syndrome among national service pre-enlistees in Singapore.

Background: All Singaporean males undergo medical screening prior to compulsory military service. A history of possible food allergy may require referral to a specialist Allergy clinic to ensure that special dietary needs can be taken into account during field training and deployment.

Objective: To study the pattern of food allergy among pre-enlistees who were referred to a specialist allergy clinic to work up suspected food allergy.

Cause and Clinical Presentation of Anaphylaxis in Singapore: From Infancy to Old Age.

Background: The study objective was to compare age-related differences in the cause and clinical presentation of anaphylaxis.

Methods: We conducted a prospective study of patients visiting the emergency department for anaphylaxis. Data were collected from 3 emergency departments from 1 April 2014 to 31 December 2015.

Relapsing drug-induced hypersensitivity syndrome.

Purpose Of Review: Drug-induced hypersensitivity syndrome (DIHS) is a serious adverse drug reaction with potential morbidity and mortality. 'Flare up' or relapses in DIHS is a rare but important feature. These relapses may occur within days to several weeks, even after discontinuation of the offending drug.

A retrospective study on sequential desensitization-rechallenge for antituberculosis drug allergy.

Background: Antituberculosis (anti-TB) drug allergy often involves multiple concurrently administered drugs which subsequently need to be reinitiated as no better alternatives exist.

Objective: To describe the results of tailored sequential desensitization-rechallenge (D-R) for anti-TB drug allergy.

Methods: Consecutive patients who had undergone D-R to anti-TB drugs between 1 September 1997 and 31 January 2012 were recruited.

Symmetrical drug-related intertriginous and flexural exanthema.

Purpose Of Review: Symmetrical drug-related intertriginous and flexural exanthema (SDRIFE), previously termed drug-related baboon syndrome, is a benign and self-limiting type IV hypersensitivity reaction characterized by symmetrical erythema involving the gluteal and intertriginous areas in the absence of systemic involvement. It may also occur in the absence of previous drug exposure.

Recent Findings: Antibiotics, in particular beta-lactams, comprise the majority of causes of SDRIFE.