There are geographical, regional, and ethnic differences in the phenotypes and endotypes of patients with drug hypersensitivity reactions (DHRs) in different parts of the world. In Asia, aspects of drug hypersensitivity of regional importance include IgE-mediated allergies and T-cell-mediated reactions, including severe cutaneous adverse reactions (SCARs), to beta-lactam antibiotics, antituberculous drugs, nonsteroidal anti-inflammatory drugs (NSAIDs) and radiocontrast agents. Delabeling of low-risk penicillin allergy using direct oral provocation tests without skin tests have been found to be useful where the drug plausibility of the index reaction is low. Genetic risk associations of relevance to Asia include human leucocyte antigen (HLA)-B*1502 with carbamazepine SCAR, and HLA-B*5801 with allopurinol SCAR in some Asian ethnic groups. There remains a lack of safe and accurate diagnostic tests for antituberculous drug allergy, other than relatively high-risk desensitization regimes to first-line antituberculous therapy. NSAID hypersensitivity is common among both adults and children in Asia, with regional differences in phenotype especially among adults. Low dose aspirin desensitization is an important therapeutic modality in individuals with cross-reactive NSAID hypersensitivity and coronary artery disease following percutaneous coronary intervention. Skin testing allows patients with radiocontrast media hypersensitivity to confirm the suspected agent and test for alternatives, especially when contrasted scans are needed for future monitoring of disease relapse or progression, especially cancers.
Adult ; Allopurinol ; Anaphylaxis ; Anti-Bacterial Agents ; Asia ; Asian Continental Ancestry Group ; Aspirin ; Asthma ; Carbamazepine ; Child ; Cicatrix ; Contrast Media ; Coronary Artery Disease ; Diagnostic Tests, Routine ; Drug Hypersensitivity ; Ethnic Groups ; Humans ; Hypersensitivity ; Penicillins ; Percutaneous Coronary Intervention ; Phenotype ; Recurrence ; Skin Tests

INTRODUCTIONEnterovirus infections in childhood can be associated with significant neurological morbidity. This study aimed to describe the prevalence and range of neurological manifestations, determine the clinical characteristics and assess differences in clinical outcomes for Singaporean children diagnosed with enterovirus infections.

METHODSIn this single-centre, case-control study, clinical data was collected retrospectively from patients admitted to National University Hospital, Singapore, from August 2007 to October 2011 and diagnosed with enterovirus infection, based on the enterovirus polymerase chain reaction test, or cultures from throat and rectal swabs or cerebrospinal fluid samples. The occurrence of neurological manifestations was reviewed and clinical outcomes were assessed.

RESULTSA total of 48 patients (age range: six days-17.8 years) were included in the study. Neurological manifestations were seen in 75.0% of patients, 63.9% of whom presented with aseptic meningitis. Other neurological manifestations included encephalitis, acute cerebellitis, transverse myelitis and autonomic dysfunction. The incidence of neurological manifestations was significantly higher in patients aged > 1 year as compared to younger patients (p = 0.043). In patients without neurological manifestations, a significantly higher proportion presented with hand, foot and mouth disease and poor feeding. Long-term neurological sequelae were seen in 16.7% of patients with neurological manifestations.

CONCLUSIONA wide spectrum of neurological manifestations resulting in a relatively low incidence of long-term neurological sequelae was observed in our study of Singaporean children with enterovirus infections. As some of these neurological morbidities were severe, careful evaluation of children with neurological involvement is therefore necessary.