Updated consensus statements on COVID-19 Vaccine Allergy Safety in Hong Kong.

Due to global concerns over coronavirus disease 2019 (COVID-19) vaccine-associated allergic reactions; the Hong Kong Institute of Allergy (HKIA) formulated an initial set of consensus statements (CS) on COVID-19 Vaccine Allergy Safety (VAS) in early 2021. Following accumulation of both local and international experience on and COVID-19 VAS, the HKIA task force reformed to update the Hong Kong consensus on COVID-19 VAS. A nominated task force of experts managing patients with drug and vaccine allergies in Hong Kong formulated the updated CS by unanimous decision. A total of 9 new statements were established. Individuals with history of food allergies and anaphylaxis unrelated to the components of COVID-19 vaccines do not require allergist review prior to vaccination. Individuals with history suspicious of an excipient allergy may now be vaccinated with a non-PEG containing vaccine without prior allergist assessment. Individuals with suspected mild allergic reactions following prior COVID-19 vaccination can proceed with the next dose. Only individuals who present with immediate-type allergic reaction with systemic symptoms or more severe nonimmediate type reactions should defer their next dose until allergist review. The remaining statements regarding adequate safety during vaccination and advocation for legislative changes regarding excipient disclosure in Hong Kong remained unchanged from the prior CS. The updated CS are updated in accordance with local and international experience thus far and serve as guidance for local frontline healthcare providers to further promote safe COVID-19 vaccine uptake in Hong Kong.

Topical therapy with negative allosteric modulators of the calcium-sensing receptor (calcilytics) for the management of asthma: the beginning of a new era?

In this review article we present the evidence to date supporting the role of the calcium-sensing receptor (CaSR) as a key, pluripotential molecular trigger for asthma and speculate on the likely benefits of topical therapy of asthma with negative allosteric modulators of the CaSR: calcilytics.

IgE reactivity patterns in Asian and central European cockroach-sensitized patients reveal differences in primary sensitizing allergen sources.

Background: The prevalence of cockroach (CR) sensitization and its relevance as a trigger of allergy symptoms differs greatly in different geographic areas. Objective: This study aimed to compare molecular IgE reactivity profiles in CR-sensitized patients with perennial allergy symptoms from Hong Kong (HK) and Austria and identify the main primary sensitizers. Methods: IgE sensitization was assessed by skin prick test and/or IgE reactivity with CR extract. Molecular IgE reactivity profiles were analyzed via multiplex assay for sensitization to allergens and extracts from CR, house dust mite (HDM), shellfish, and 3 additional insect species. Results: HDM was the main primary sensitizer in both cohorts. In the HK group, genuine sensitization to CR was found in 45%, but none of the patients in the Austrian cohort was truly sensitized to that allergen source. Most patients from HK were cross-sensitized to other insects and/or shellfish, presumably by broad reactivity to tropomyosin and arginine kinase. About half of Austrian subjects lacked IgE to these pan-allergens, indicating co- but not cross-sensitization to insects and/or shellfish. Regarding IgE recognition frequencies, arginine kinases (64% HK, 10% Austria) and tropomyosins (42% HK, 15% Austria) were most frequently recognized; Bla g 4 (lipocalin) was detected in HK patients only (42%). Tropomyosin (Per a 7) was significantly more frequently recognized in patients with asthma. Sera from HDM-sensitized subjects from HK showed a higher proportion of sensitization to minor mite allergens. Conclusion: Molecular profiling identified differences between CR-sensitized allergic patients from HK and Austria in terms of primary sensitizers and molecular IgE reactivity patterns. Tropomyosin from American cockroach (Per a 7) was shown to be significantly associated with asthma symptoms and might be suitable as biomarker for more severe respiratory allergy symptoms.

Experience of the first 1127 COVID-19 Vaccine Allergy Safety patients in Hong Kong - Clinical outcomes, barriers to vaccination, and urgency for reform.

INTRODUCTION: Hong Kong has had a low incidence of COVID-19 vaccine related anaphylaxis, partly due to its Vaccine Allergy Safety (VAS) guidelines for screening those at higher risk of COVID-19 vaccine-associated allergic reactions. We characterize the initial experience of the VAS clinics, as well as the impact of unnecessary referrals to the vaccination program. METHODS: All patients attending the VAS Clinics of the public and private health services between February and June 2021 were reviewed. RESULTS: Out of 1127 patients assessed at VAS clinics, 1102 (97.8%) patients were recommended for vaccination. Out of those contacted, more than 80% (450/558) received vaccination successfully; the remaining had not yet booked their vaccinations. The majority (87.5%) of patients not recommended was due to potential excipient allergies. Males were significantly more likely to be recommended (OR = 5.822, 95% CI = 1.361-24.903, p = 0.007), but no other features were associated with recommendation for vaccination. Almost half (45.1%) of public service referrals were rejected due to insufficient information or incorrect indications for referral. The majority of cases (56.2%) of patients referred for suspected "anaphylaxis" did not fulfil diagnostic criteria. DISCUSSION: COVID-19 vaccination is very safe and 98% of high-risk patients were recommended for vaccination. Barriers to VAS include a high proportion of inappropriate referrals, inaccurate diagnoses of anaphylaxis and inability to diagnose excipient allergies. Our data validates that a prior history of COVID-vaccine unrelated anaphylaxis should be removed as a precaution for vaccination. Closer collaborations between primary care and allergy specialists and changes in pharmaceutical legislation should be made a priority to promote vaccination uptake.

Hong Kong Anaphylaxis Consortium Consensus Statements on prescription of adrenaline autoinjectors in the acute care setting.

BACKGROUND: Adrenaline autoinjectors (AAInj) facilitates early administration of adrenaline and remains the first-line treatment for anaphylaxis. However, only a minority of anaphylaxis survivors in Hong Kong are prescribed AAInj and formal guidance do not exist. International anaphylaxis guidelines have been largely based on Western studies, which may not be as relevant for non-Western populations. OBJECTIVE: To formulate a set of consensus statements on the prescription of AAInj in Hong Kong. METHODS: Consensus statements were formulated by the Hong Kong Anaphylaxis Consortium by the Delphi method. Agreement was defined as greater than or equal to 80% consensus. Subgroup analysis was performed to investigate differences between allergy and emergency medicine physicians. RESULTS: A total of 7 statements met criteria for consensus with good overall agreement between allergy and emergency medicine physicians. AAInj should be used as first-line treatment and prescribed for all patients at risk of anaphylaxis. This should be prescribed prior to discharge from the Accident and Emergency Department together with an immediate referral to an allergy center. The decision for prescribing AAInj should be based on the severity of previous reactions; including objective signs of respiratory involvement, objective signs of cardiovascular involvement and multiorgan involvement (regardless of severity). Patient demographics and comorbidities, specifically history of asthma or chronic obstructive pulmonary disease, should also be considered. Patients deemed eligible for AAInj should be offered avoidance advice and prescribed one AAInj while awaiting review by allergists. AAInj technique should be demonstrated by a healthcare professional or instruction video, and a return demonstration by the patient is required. The patient should also be counseled that the decision on the continued need of AAInj prescription in the long-term should be reviewed by an allergist. CONCLUSION: Consensus statements support the prescription of AAInj by front-line physicians with subsequent allergist review when treating patients at risk of anaphylaxis in Hong Kong.

Consensus Statements on the Approach to COVID-19 Vaccine Allergy Safety in Hong Kong.

Background: Mass coronavirus disease 2019 (COVID-19) vaccination to achieve herd immunity is an effective means to mitigate the current COVID-19 pandemic. Reports of COVID-19 vaccine-associated allergic reactions and lack of clear local guidance are contributing factors leading to a low vaccine acceptance rate in the community. A task force of experts from the Hong Kong Institute of Allergy (HKIA) has been formed to address current needs. Objective: To formulate a set of consensus statements (CS) on COVID-19 vaccine allergy safety (VAS) in Hong Kong. Methods: A nominated task force of experts managing patients with drug and vaccine allergies in Hong Kong formulated the CS by the Delphi method. An agreement was a priori defined as ≥80% consensus. Results: A total of 11 statements met the criteria for consensus with good overall agreement among task force members, including seven statements on pre-vaccination recommendations and four statements on vaccination and post-vaccination guidance. Individuals with a history of suspected allergic reaction to prior COVID-19 vaccination should not receive further COVID-19 vaccination, and other groups at risk of COVID-19 vaccine-associated allergic reactions have been identified. The importance of pre-vaccination and post-vaccination assessment by frontline healthcare workers and evaluation by allergists are highlighted. Conclusion: The CS provides pragmatic and timely guidance for local frontline healthcare providers on decisions regarding COVID-19 VAS.

The effectiveness of sublingual immunotherapy for house dust mite-induced allergic rhinitis and its co-morbid conditions.

Aim: We investigated sublingual immunotherapy for mite-induced allergic rhinitis and its comorbid allergic conditions. Patients & methods: A prospective case-controlled study of 120 patients (case = 80, control = 40) over 12 months. Results: There was 53.6% reduction in total rhinitis symptom score (p < 0.0001), but not in controls (-7.3%, p = 0.99). The total symptom scores for concurrent asthma decreased from 17.79 to 8.8 (p < 0.0001); for allergic conjunctivitis from 20.89 to 10.0 (p = 0.0002); for atopic dermatitis from 46.40 to 29.38 (p = 0.0004) and 74.6% of patients weaned off nasal topical steroids. The treatment-related adverse reactions were mild and self-limiting. Conclusion: Though sublingual immunotherapy may be more expensive than conventional treatments, it was an adjunctive therapy that improved not only the outcomes for allergic rhinitis, but also its comorbid allergic conditions.

The unmet provision of allergy services in Hong Kong impairs capability for allergy prevention-implications for the Asia Pacific region.

INTRODUCTION: There is a high and rising prevalence of many allergic diseases in the Asia Pacific, including Hong Kong (HK), which is unmatched by a commensurate provision of clinical allergy services. METHOD: This review highlights progress and deficiencies in allergy service and training in HK. The allergy work force was estimated from the numbers of doctors practicing allergy registered with the HK Medical Council Specialist Register in Immunology and Allergy; Paediatric Immunology and Infectious Diseases (includes allergy); Paediatrics; and Immunology (as a discipline of Pathology). The numbers of trainees were estimated from the trainee lists of the Hong Kong Colleges of Physicians, Paediatrics and Pathology. The numbers of allergy clinics were estimated from existing services in Hospital Authority public hospitals in HK. RESULTS: In the last 3 years, two new drug allergy clinics have been established in public hospitals, and for the first time in 20 years, Hong Kong has a trainee in adult allergy. The current ratio of allergists per head of population has improved slightly from 1:1.46 million in 2014 to 1:1.17 million, but it is still low compared to many countries. There are 5-fold more paediatric allergists than adult allergists per head of population in HK. DISCUSSION: Hong Kong is not equipped to take advantage of major public health advances in allergy prevention. If the unbalance of adult to paediatric allergists remains uncorrected, continuing care for allergic children as they grow into adulthood will be an increasing problem. CONCLUSION: Hong Kong still has an unmet need for allergy specialists and is ill equipped to exploit recently discovered public health opportunities to prevent allergy. This review provides recommendations to improve allergy service provision and training, including the creation of Centres of Excellence in allergy to drive the growth of the specialty.

Selecting optimal second-generation antihistamines for allergic rhinitis and urticaria in Asia.

BACKGROUND: Allergic diseases are on the rise in many parts of the world, including the Asia-Pacific (APAC) region. Second-generation antihistamines are the first-line treatment option in the management of allergic rhinitis and urticaria. International guidelines describe the management of these conditions; however, clinicians perceive the additional need to tailor treatment according to patient profiles. This study serves as a consensus of experts from several countries in APAC (Hong Kong, Malaysia, the Philippines, Singapore, Thailand, Vietnam), which aims to describe the unmet needs, practical considerations, challenges, and key decision factors when determining optimal second-generation antihistamines for patients with allergic rhinitis and/or urticaria. METHODS: Specialists from allergology, dermatology, and otorhinolaryngology were surveyed on practical considerations and key decision points when treating patients with allergic rhinitis and/or urticaria. RESULTS: Clinicians felt the need for additional tools for diagnosis of these diseases and a single drug with all preferred features of an antihistamine. Challenges in treatment include lack of clinician and patient awareness and compliance, financial constraints, and treatment for special patient populations such as those with concomitant disease. Selection of optimal second-generation antihistamines depends on many factors, particularly drug safety and efficacy, impact on psychomotor abilities, and sedation. Country-specific considerations include drug availability and cost-effectiveness. Survey results reveal bilastine as a preferred choice due to its high efficacy and safety, suitability for special patient populations, and the lack of sedative effects. CONCLUSIONS: Compliance to the international guidelines is present among allergists, dermatologists and otorhinolaryngologists; however, this is lower amongst general practitioners (GPs). To increase awareness, allergy education programs targeted at GPs and patients may be beneficial. Updates to the existing international guidelines are suggested in APAC to reflect appropriate management for different patient profiles and varying symptoms of allergic rhinitis and urticaria.