Safety and immunogenicity of 3 doses of BNT162b2 and CoronaVac in children and adults with inborn errors of immunity.

Our study (NCT04800133) aimed to determine the safety and immunogenicity in patients with IEIs receiving a 3-dose primary series of mRNA vaccine BNT162b2 (age 12+) or inactivated whole-virion vaccine CoronaVac (age 3+) in Hong Kong, including Omicron BA.1 neutralization, in a nonrandomized manner. Intradermal vaccination was also studied. Thirty-nine patients were vaccinated, including 16 with homologous intramuscular 0.3ml BNT162b2 and 17 with homologous intramuscular 0.5ml CoronaVac. Two patients received 3 doses of intradermal 0.5ml CoronaVac, and 4 patients received 2 doses of intramuscular BNT162b2 and the third dose with intradermal BNT162b2. No safety concerns were identified. Inadequate S-RBD IgG and surrogate virus neutralization responses were found after 2 doses in patients with humoral immunodeficiencies and especially so against BA.1. Dose 3 of either vaccine increased S-RBD IgG response. T cell responses against SARS-CoV-2 antigens were detected in vaccinated IEI patients by intracellular cytokine staining on flow cytometry. Intradermal third dose vaccine led to high antibody response in 4 patients. The primary vaccination series of BNT162b2 and CoronaVac in adults and children with IEIs should include 3 doses for optimal immunogenicity.

Invasive cerebral phaeohyphomycosis in a Chinese boy with CARD9 deficiency and showing unique radiological features, managed with surgical excision and antifungal treatment.

We report this rare case of cerebral phaeohyphomycosis in a previously healthy Chinese boy, who was found to have caspase recruitment domain family member 9 (CARD9) deficiency. Initial radiological features suggested a neoplastic cerebral lesion, while histopathological examination supplemented by internal transcribed sequencing (ITS) of cerebral tissue confirmed the diagnosis of phaeohyphomycosis. He was treated with intravenous (IV) liposomal amphotericin B and voriconazole, guided by plasma and cerebrospinal fluid (CSF) level monitoring at drug initiation. At the 1 year follow-up, the patient demonstrated near complete neurological and radiological recovery.

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.

Skin prick testing a better predictor than blood testing for the diagnosis of peanut allergy in Chinese children.

BACKGROUND: Peanut allergy is common in Chinese children, yet the most predictive diagnostic cut-offs for skin prick test (SPT) and blood testing in this population are unclear. OBJECTIVES: We aimed to determine the optimal cut-off values for whole-peanut SPT, specific IgE (sIgE) and component-resolved diagnostics (CRD) for Chinese children based on outcomes of open oral food challenges (OFC) to peanut. METHODS: We recruited ethnic-Chinese patients 1-18 years old who were suspected of having peanut allergy based on a history of reactions after exposure or sensitization although peanut naïve. Considering the AUC value of 0.8, 80% power and 5% level of significance with two tails, 26 patients were needed. Sensitivities, specificities, positive and negative predictive values, and receiver operating characteristic curves (ROCs) and their area-under-curves (AUCs) for SPT, peanut sIgE, and CRD were compared. RESULTS: Thirty-one subjects participated. Only SPT reached statistical significance (AUC 0.91, p = 0.0001), but not the other tests. Seven retrospective data were added to optimize the power. SPT remained to be the best predictor, followed by Ara h 2 sIgE (AUC 0.72, p = 0.02). An SPT wheal size of 3 mm and Ara h 2 sIgE of 0.14 kU(A)/L yielded the highest Youden's index. The specificity of SPT and Ara h 2 sIgE reached 94% at 6 mm and 0.74 kU(A)/L, respectively. Comparisons of ROCs revealed that SPT was significantly better than Ara h 2 sIgE (p = 0.03) and whole-peanut sIgE (AUC 0.61, p = 0.26). CONCLUSION: In Chinese children, SPT appeared to be the best predictor for peanut allergy, followed by Ara h 2 sIgE.

Risk factors for drug allergies in Chinese children.

BACKGROUND: Drug allergy, or drug hypersensitivity, is a potentially fatal disorder, and patients labeled with drug allergies have restricted access to first-line treatments. Full knowledge of the characteristics associated with drug allergies and severe reactions during allergy evaluation is beneficial for appropriate risk stratification. OBJECTIVE: We sought to determine whether certain clinical characteristics are associated with drug allergies in Chinese children. METHODS: Charts were reviewed for ethnic Chinese patients less than 18 years old referred to our tertiary allergy center for suspected drug allergies and completed skin and drug provocative testing between 2005 to 2017. Univariate and multivariate analyses were performed on the age of onset of drug allergies, gender, and other atopy versus drug allergies. RESULTS: Out of 75 children, 18 (24%) had IgE-mediated drug allergies, while 8 (10.7%) had delayed drug hypersensitivities, with a cumulative 26 subjects (34.7%) with any drug hypersensitivity. There were positive independent associations between drug hypersensitivities onset age vs IgE-mediated drug allergies (odds ratio (OR) = 14.9, 95% confidence intervals (CIs) = 1.5-148.3, P = 0.017) and between male gender and IgE-mediated drug allergies (OR = 4.4, CIs = 1.2-16.4, P = 0.019). Age 13 years was the best cut-off for IgE-mediated drug allergies according to the receiver operating characteristic curve (P = 0.026). Older age group (OR = 24.0, CIs = 1.4-417.8, P = 0.024) and atopic dermatitis (OR = 8.2, CIs = 1.4-49.8, P = 0.015) were correlated with delayed drug hypersensitivities. CONCLUSIONS: While several previous studies suggested a higher prevalence of IgE-mediated drug allergies in younger adult females, older boys were more likely to have drug allergies for Chinese children.