Elizabeth Huiwen Tham

Epinephrine auto-injector prescriptions as a reflection of the pattern of anaphylaxis in an Asian population.

This study surveyed the prescription patterns of adrenaline auto-injectors (AAs) in Singapore to examine the frequency, triggers, and demographic pattern of anaphylaxis requiring such prescriptions. A 6-year retrospective review of 417 consecutive patients prescribed AAs in Singapore from January 1999 to December 2004, as identified from hospital pharmacy records. There were 417 patients identified, consisting of 295 (70.7%) Singaporeans with the remaining being non-Singaporean residents. Based on population census, the frequency of AA prescriptions was estimated at 1 per 10,000 Singaporeans. Demographic factors associated with AA prescriptions were male gender (OR = 1.361; p = 0.002); minority ethnic groups, which included Eurasians, Caucasians, Koreans, and Japanese (OR = 15.873; p < 0.001); and children <15 years of age (OR = 2.593; p < 0.001). The most common food allergens resulting in AA prescriptions were peanut (41.9%) and shellfish allergy (28.5%). Multiple logistic regression analysis showed that peanut allergy was independently associated with Eurasian ethnicity (OR = 5.045; p = 0.021); and shellfish allergy with Indian ethnicity (OR = 2.757; p = 0.034). The estimated frequency of AA prescriptions in Singapore is relatively low at 0.01%. The incidence of peanut and shellfish allergy in the Asian population appears to differ from that seen in Western populations.

Aeroallergen sensitization and allergic disease phenotypes in Asia.

Allergic diseases are on the rise in Asia. Aeroallergen exposure is a strong risk factor for sensitization, development and severity of atopic diseases, especially in the Asian paediatric population. Geographical and seasonal variations in aeroallergen sensitization are seen even within Asian countries and changes in aeroallergen sensitization patterns have been observed over time. Some possible reasons include climate change as well as rapid urbanization and improved sanitation which follow socioeconomic development. House dust mite allergy is present in up to 90% of Asian atopic patients, far exceeding that which is seen in Western populations which report prevalences of only 50% to 70%. Pollen and animal dander affect less than 10% of Asian patients as compared to 40-70% of individuals with asthma and allergic rhinitis living in the West, a burden almost equivalent to the dust mite burden in those regions. There is thus a pressing need for preventive measures to reduce dust mite sensitization in Asian children today.

Low Food Allergy Prevalence Despite Delayed Introduction of Allergenic Foods—Data from the GUSTO Cohort

BACKGROUND There is mounting evidence that early introduction of allergenic food decreases the risk of food allergy development, especially in high-risk infants with eczema. However, there is a lack of data to suggest whether this association holds true in Asian populations. OBJECTIVE To investigate the relationship between the timing of introduction of allergenic foods and food allergy outcomes in infants in the Growing Up in Singapore Towards healthy Outcomes (GUSTO) study. METHODS The GUSTO cohort recruited 1152 mothers of Chinese, Malay, and Indian ethnicity who had singleton, naturally conceived pregnancies and followed their offspring prospectively. Information on demographic characteristics, child health, infant feeding practices, and a convincing history of IgE-mediated food allergy was obtained from interviewer-administered questionnaires at multiple time points. Corroborative skin prick tests to food allergens were performed at 18 and 36 months. RESULTS Most of the infants were introduced to egg (49.6%), peanut (88.7%), and shellfish (90.2%) after age 10 months. Food allergy prevalence was, however, very low between age 12 and 48 months: egg, 0.35% to 1.8%; peanut allergy, 0.1% to 0.3%; and shellfish, 0.2% to 0.9%. There were no significant associations between the timing of introduction of allergenic foods and the development of food allergy, adjusted for confounders including breast-feeding and eczema. CONCLUSIONS Food allergy rates in Singapore are low despite delayed introduction of allergenic foods. Early introduction of allergenic foods may thus not be necessary in populations in which overall food allergy prevalence is low, and thus infant feeding recommendations should be carefully tailored to individual populations.

Evaluation and management of hypersensitivity reactions to chemotherapy agents

Hypersensitivity reactions to chemotherapy drugs pose significant difficulties in management, especially when no suitable alternative is available or acceptable and delay in continuation of treatment may be life-threatening. Such reactions may be IgE- or non-IgE-mediated and have varied manifestations. Timely recognition and treatment of life-threatening hypersensitivity reactions are essential. Identification of patients at high risk of developing hypersensitivity reactions allows risk stratification to guide clinical decision-making. Skin testing for carboplatin hypersensitivity has good predictive value but is not yet established for oxaliplatin and taxane hypersensitivity. Rapid desensitisation may be considered if no suitable alternative drug is available. Available protocols have shown good safety and efficacy but must be performed in an appropriate setting with adequate monitoring. There are many avenues for research into the utility of skin testing for other chemotherapy agents as well as in vitro tests.

Early Introduction of Allergenic Foods for the Prevention of Food Allergy from an Asian Perspective – An APAPARI Consensus Statement

Emerging evidence for the early introduction of allergenic foods for the prevention of food allergies, such as peanut allergy in Western populations, has led to the recent publication of guidelines in the USA and Europe recommending early peanut introduction for high‐risk infants with severe eczema or egg allergy. Peanut allergy is, however, much less prevalent in Asia compared to the West. Varying patterns of food allergy are seen even within Asian countries—such as a predominance of wheat allergy in Japan and Thailand and shellfish allergy in Singapore and the Philippines. Customs and traditions, such as diet and infant feeding practices, also differ between Asian populations. Hence, there are unique challenges in adapting guidelines on early allergenic food introduction to the Asian setting. In this paper, we review the evidence and discuss the possible approaches to guide the timely introduction of allergenic food in high‐risk infants in Asia.

Novel strategies in immunotherapy for allergic diseases

Conventional immunotherapy (IT) for optimal control of respiratory and food allergies has been fraught with concerns of efficacy, safety, and tolerability. The development of adjuvants to conventional IT has potentially increased the effectiveness and safety of allergen IT, which may translate into improved clinical outcomes and sustained unresponsiveness even after cessation of therapy. Novel strategies incorporating the successful use of adjuvants such as allergoids, immunostimulatory DNA sequences, monoclonal antibodies, carriers, recombinant proteins, and probiotics have now been described in clinical and murine studies. Future approaches may include fungal compounds, parasitic molecules, vitamin D, and traditional Chinese herbs. More robust comparative clinical trials are needed to evaluate the safety, clinical efficacy, and cost effectiveness of various adjuvants in order to determine ideal candidates in disease-specific and allergen-specific models. Other suggested approaches to further optimize outcomes of IT include early introduction of IT during an optimal window period. Alternative routes of administration of IT to optimize delivery and yet minimize potential side effects require further evaluation for safety and efficacy before they can be recommended.

How Different Parts of the World Provide New Insights Into Food Allergy

The prevalence and patterns of food allergy are highly variable in different parts of the world. Differences in food allergy epidemiology may be attributed to a complex interplay of genetic, epigenetic, and environmental factors, suggesting that mechanisms of food allergy may differ in various global populations. Genetic polymorphisms, migration, climate, and infant feeding practices all modulate food allergy risk, and possibly also the efficacy of interventions aimed at primary prevention of food allergy development. Approaches to diagnosis, treatment, and prevention of food allergy should thus be tailored carefully to each populations unique genetic and environmental make-up. Future research in the context of food allergy prevention should focus on elucidating factors determining differential responses between populations.

Associations between maternal vitamin D levels during pregnancy and allergic outcomes in the offspring in the first 5 years of life

There is increasing evidence to support the Developmental Origins of Health and Disease (DOHaD) concept that fetal life and early life exposures are important determinants of fetal immune regulation and the development of disorders in later life, including allergies. Among the early life exposures, maternal vitamin D [25(OH)D] status during pregnancy, in particular 25(OH)D insufficiency (25(OH)D concentration of 50-75nmol/l) and/or 25(OH)D deficiency (25(OH)D concentration <50nmol/l) has been associated with allergic outcomes such as eczema, asthma and rhinitis in their offspring. This article is protected by copyright. All rights reserved.

Successful desensitization to gonadotropin-releasing hormone analogue triptorelin acetate using a sustained-release depot preparation

Gonadotropin-releasing hormone (GnRH) analogues are commonly used in pediatric patients in the treatment of central precocious puberty1 . GnRH analogues suppress the secretion of gonadotropins and sex hormones, preventing progression to advanced puberty and reduced final adult height secondary to accelerated fusion of growth plates. GnRH analogues are also used in adults for treatment of endometriosis2 and prostatic cancer3 . Hypersensitivity reactions to GnRH analogues are exceedingly rare4-6 and to date, we are unaware of any desensitization protocols for GnRH hypersensitivity in the literature or used in clinical practice. This article is protected by copyright. All rights reserved.