Impact of Immunomodulatory Therapy on COVID-19 Vaccine Response in Patients with Autoimmune Inflammatory Rheumatic Diseases.

Coronavirus disease 2019 (COVID-19) vaccination is essential for patients with autoimmune inflammatory rheumatic diseases (AIIRD) to reduce the risk of morbidity and mortality associated with serious COVID-19 infection. With endemicity, waning of vaccine- and infection-acquired immunity, and development of SARS-CoV-2 variants, the need for additional doses of vaccines against serious illness in high-risk immunocompromised persons remains imperative. This review examines how immunomodulatory therapies affect vaccine-induced immune response in patients with AIIRD. Glucocorticoids, methotrexate, azathioprine, calcineurin inhibitors, mycophenolate mofetil, tumor necrosis factor inhibitors, and abatacept have been shown to variably attenuate both humoral and cellular immune responses to vaccination. Janus kinase inhibitors reduce humoral immune response. In contrast, sulfasalazine, leflunomide, belimumab, interleukin (IL)-17, IL-12/23, IL-6, and IL-1 inhibitors appear favorable, with mild or no impact on vaccine response. Although rituximab is known to profoundly diminish humoral immune response, cellular immunity is relatively preserved. Administering a third and subsequent vaccine dose or temporally coordinating the dosing of immunomodulatory drugs may improve vaccine effectiveness. Further research is needed to personalise vaccination strategies for AIIRD patients, considering their specific immunomodulatory treatments.

Uncovering the true burden of hereditary angioedema due to C1-inhibitor deficiency: A focus on the Asia-Pacific region.

Hereditary angioedema (HAE) due to C1-inhibitor deficiency or dysfunction is a rare genetic disorder that causes recurrent episodes of swelling in various parts of the body. Treatment goals of HAE aim to "normalize" life for all patients; however, lack of diagnostic facilities and limited access to effective treatment options in developing nations cause delays in diagnosis and place a significant burden on patients. In this review, we aim to highlight the burden of disease caused by C1-inhibitor HAE across the Asia-Pacific region, considering its epidemiology, morbidity and mortality, and socioeconomic and psychological impact. We also review the availability of guideline-recommended diagnostic facilities and treatments, and how patients are currently managed. Data were collected from published literature and HAE experts in the region, who provided information regarding diagnosis and management in their countries. Current practice was reviewed against international guidelines, as well as local guidelines/consensus used in Australia, Japan, and China. Suggestions are provided for improving the time to diagnosis in the region, increasing access to guideline-recommended treatments, and providing support to reduce the burden on patients and caregivers. There is an urgent need to improve HAE services and provide access to life-saving treatment in developing countries, and efforts should be made to increase awareness of guideline recommendations in high-income economies that do not currently provide long-term prophylactic treatments.

APAAACI clinical pathway on direct provocation testing for penicillin allergy delabeling.

Background: Allergy to penicillin is commonly reported in many countries and is an overwhelming global public health concern. Penicillin allergy labels can lead to the use of less effective antibiotics and can be associated with antimicrobial resistance. Appropriate assessment of suspected penicillin allergy (often including skin testing, followed by drug provocation testing [DPT] performed by allergists) can prevent the unnecessary restriction of penicillin or delabelling. Many countries in the Asia Pacific (AP) have very limited access to allergy services, and there are significant disparities in the methods of evaluating penicillin allergy. Therefore, a clinical pathway for the management of penicillin allergy is essential. Objectives: To develop a risk-stratified clinical pathway for delabeling penicillin allergy, taking into account the distinct epidemiology, patient/sensitization profiles, and disparities of allergy services or facilities within the AP. Methods: A risk-stratified penicillin allergy delabeling clinical pathway was formulated by the Drug Allergy Committee of the Asia Pacific Association of Allergy, Asthma and Clinical Immunology. and members of the Penicillin Allergy Disparities survey in AP each representing one country/region of the AP. The clinical pathway was tested based on a database of anonymized patients who were sequentially referred for and completed penicillin allergy evaluation in Hong Kong. Results: The clinical pathway was piloted employing a "hub-and-spoke" approach to foster multidisciplinary collaboration between allergists and nonallergists. A simulation run of the algorithm on a retrospective Hong Kong cohort of 439 patients was performed. Overall, 367 (84%) of patients were suitable for direct DPT and reduced the need for skin testing or specialist's care for 357 (97%) skin test-negative individuals. Out of the skin test-negative patients, 345 (94%) patients had a negative DPT. Conclusions: This risk-stratification strategy for direct oral DPT can reduce the need for unnecessary skin testing in patients with low-risk penicillin allergy histories. The hub and spoke model of care may be considered for further piloting and validation in other AP populations that lack adequately trained allergists.

Global disparities in availability of epinephrine auto-injectors.

Background: Anaphylaxis is the most severe clinical presentation of acute systemic allergic reactions and can cause death. Given the prevalence of anaphylaxis within healthcare systems, it is a high priority public health issue. However, management of anaphylaxis - both acute and preventative - varies by region. Methods: The World Allergy Organization (WAO) Anaphylaxis Committee and the WAO Junior Members Steering Group undertook a global online survey to evaluate local practice in the diagnosis and management of anaphylaxis across regions. Results: Responses were received from WAO members in 66 countries. While intramuscular epinephrine (adrenaline) is first-line treatment for anaphylaxis, some countries continue to recommend alternative routes in contrast to guidelines. Epinephrine auto-injector (EAI) devices, prescribed to individuals at ongoing risk of anaphylaxis in the community setting, are only available in 60% of countries surveyed, mainly in high-income countries. Many countries in South America, Africa/Middle-East and Asian-Pacific regions do not have EAI available, or depend on individual importation. In countries where EAIs are commercially available, national policies regarding the availability of EAIs in public settings are limited to few countries (16%). There is no consensus regarding the time patients should be observed following emergency treatment of anaphylaxis. Conclusion: This survey provides a global snapshot view of the current management of anaphylaxis, and highlights key unmet needs including the global availability of epinephrine for self-injection as a key component of anaphylaxis management.

Epidemiology of the idiopathic inflammatory myopathies.

The idiopathic inflammatory myopathies (IIMs) are a heterogeneous group of systemic autoimmune diseases that affect the skeletal muscles and can also involve the skin, joints, lungs and heart. The epidemiology of IIM is obscured by changing classification criteria and the inherent shortcomings of case identification using healthcare record diagnostic coding. The incidence of IIM is estimated to range from 0.2 to 2 per 100,000 person-years, with prevalence from 2 to 25 per 100,000 people. Although the effects of age and gender on incidence are known, there is only sparse understanding of ethnic differences, particularly in indigenous populations. The incidence of IIM has reportedly increased in the twenty-first century, but whether this is a genuine increase is not yet known. Understanding of the genetic risk factors for different IIM subtypes has advanced considerably. Infections, medications, malignancy and geography are also commonly identified risk factors. Potentially, the COVID-19 pandemic has altered IIM incidence, although evidence of this occurrence is limited to case reports and small case series. Consideration of the current understanding of the epidemiology of IIM can highlight important areas of interest for future research into these rare diseases.

Evaluating immune responses to pneumococcal vaccines.

Streptococcus pneumoniae (pneumococcus) is a significant cause of bacterial infections ranging from mild infections affecting the respiratory tract such as otitis media and sinusitis to severe diseases including bacteremia, pneumonia, and invasive pneumococcal disease (IPD) (eg, meningitis, septic arthritis, and endocarditis). Pneumococcal vaccines were first developed in the 1970s as capsular pneumococcal polysaccharide vaccines, which were T-cell independent and hence lacked immunologic memory. Subsequently in the year 2000, pneumococcal conjugate vaccines (PCV) conjugated to a protein to increase immunogenicity were developed and made commercially available. The increasing number of pneumococcal serotypes identified and the expanding pipeline of PCV vaccines with improved immunogenicity have significantly reduced the morbidity and mortality associated with IPD in high-risk patients. Pneumococcal vaccines also play an important role in the diagnosis and immunophenotyping of children and adults with inborn errors of immunity (IEI) given the increasing diversity/heterogeneity of IEI presenting with primary and/or specific antibody deficiency. Other than the quantitation of serotype levels in routine clinical care, other measurements of immune response including the functional activity of antibodies, antibody avidity, cell-mediated immunity, and immunological memory remain limited to clinical trials during vaccine development.

Drug-induced Stevens Johnson syndrome and toxic epidermal necrolysis: Interpreting the systematic reviews on immunomodulatory therapies.

Drug-induced Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are non-immunoglobulin E-mediated severe cutaneous adverse reactions with a high risk of morbidity, mortality, and physical and mental health impact. These are associated with certain high-risk drugs, human leukocyte antigen (HLA)-specific genotypes and ethnicities. HLA class I-restricted oligoclonal CD8 cytotoxic T-cell responses occur at the tissue level in SJS/TEN. Cytotoxic T cells are the T effector cells that result in keratinocyte apoptosis (cell death) mediated by T effector molecules granzyme B, perforin, granulysin, gamma interferon, tumor necrosis factor-alpha, and lipocalin-2. The clinical hallmarks of SJS/TEN include fever, ≥2 mucosal involvements (ocular, oral, and genital), and positive Nikolsky sign with epidermal detachment. Systematic reviews on immunomodulatory treatments remain limited by the paucity of randomized controlled trials, heterogeneity of studies, and non-standardization of outcome measures. Preventive HLA genotype screening before the prescription of carbamazepine and allopurinol may further reduce the incidence of SJS/TEN. The role of immunomodulatory treatments in SJS/TEN is at present not supported by robust evidence from systematic reviews given the lack of randomized controlled trials. The evidence for improved survival with off-label use of corticosteroids plus intravenous immunoglobulins, ciclosporin plus intravenous immunoglobulins, and ciclosporin alone has not been demonstrated by network meta-analyses and meta-regression. In the real-world clinical setting, systemic corticosteroids (in SJS and overlap SJS/TEN), ciclosporin, and etanercept (in TEN) appear to be the off-label treatments currently most widely used.

Anaphylatoxin Complement 5a in Pfizer BNT162b2-Induced Immediate-Type Vaccine Hypersensitivity Reactions.

The underlying immunological mechanisms of immediate-type hypersensitivity reactions (HSR) to COVID-19 vaccines are poorly understood. We investigate the mechanisms of immediate-type hypersensitivity reactions to the Pfizer BNT162b2 vaccine and the response of antibodies to the polyethylene glycol (PEG)ylated lipid nanoparticle after two doses of vaccination. Sixty-seven participants, median age 35 and 77.3% females who tolerated two doses of the BNT162b2 vaccine (non-reactors), were subjected to various blood-sampling time points. A separate group of vaccine reactors (10 anaphylaxis and 37 anonymised tryptase samples) were recruited for blood sampling. Immunoglobulin (Ig)G, IgM and IgE antibodies to the BNT162b2 vaccine, biomarkers associated with allergic reaction, including tryptase for anaphylaxis, complement 5a(C5a), intercellular adhesion molecule 1 (ICAM-1) for endothelial activation and Interleukin (IL)-4, IL-10, IL-33, tumour necrosis factor (TNF) and monocyte chemoattractant protein (MCP-1), were measured. Basophil activation test (BAT) was performed in BNT162b2-induced anaphylaxis patients by flow cytometry. The majority of patients with immediate-type BNT162b2 vaccine HSR demonstrated raised C5a and Th2-related cytokines but normal tryptase levels during the acute reaction, together with significantly higher levels of IgM antibodies to the BNT162b2 vaccine (IgM 67.2 (median) vs. 23.9 AU/mL, p < 0.001) and ICAM-1 when compared to non-reactor controls. No detectable IgE antibodies to the BNT162b2 vaccine were found in these patients. The basophil activation tests by flow cytometry to the Pfizer vaccine, 1,2-dimyristoyl-rac-glycero-3-methoxypolyethylene glycol (DMG-PEG) and PEG-2000 were negative in four anaphylaxis patients. Acute hypersensitivity reactions post BNT162b2 vaccination suggest pseudo-allergic reactions via the activation of anaphylatoxins C5a and are independent of IgE-mechanisms. Vaccine reactors have significantly higher levels of anti-BNT162b2 IgM although its precise role remains unclear.

Delabelling multiple antibiotic allergy: Practical issues.

With the growing incidence of multi-drug resistant organisms, delabelling incorrect antibiotic allergies has become an integral part of antimicrobial stewardship worldwide. For example, around 90% of penicillin allergy labels are found to be inaccurate following a full allergy work-up, which deprive patients the use of effective first-line penicillin antibiotics and increase the risk of antimicrobial resistance with the use of other extended spectrum non-penicillin antimicrobials. Significant numbers of adult and paediatric patients over time are labelled with multiple penicillin and non-penicillin antibiotic allergies often during inappropriate antimicrobial use, resulting in a label of "multiple antibiotic allergy". In contrast to delabelling penicillin allergy where oral direct provocation tests can be used for low-risk, mild reactions, and sensitivity/specificity/positive and negative predictive values of skin tests have been demonstrated, diagnostic tests for multiple antibiotic allergy often require the use of a combination of in-vivo and in-vitro tests across different antimicrobial classes for evaluation. Shared decision making with patients and informed consent are also needed when prioritising which drugs to delabel first, balancing the risks, benefits of testing vs. interim use of alternative antibiotics. Similar to delabelling penicillin allergy, the cost-effectiveness of delabelling multiple drug allergies is unknown.

Epidemiology, Management, and Treatment Access of Hereditary Angioedema in the Asia Pacific Region: Outcomes From an International Survey.

BACKGROUND: Hereditary angioedema (HAE) is a rare genetic disease with significant morbidity and mortality for which early diagnosis and effective therapy are critical. Many Asia Pacific (AP) countries still lack access to diagnostic tests and evidence-based therapies. Epidemiologic data from the AP is needed to formulate regional guidelines to improve standards of care for HAE. OBJECTIVE: To investigate the estimated minimal prevalence, needs, and potential interventions for the diagnosis and management of HAE in the AP. METHODS: A structured questionnaire was distributed to representative experts from member societies of the Asia Pacific Association of Allergy, Asthma and Clinical Immunology. Patient profiles and the presence of diagnostic facilities or tests, regional and national HAE guidelines, and patient support groups were reported and compared. RESULTS: Completed questionnaires were received from 14 representatives of 12 member countries and territories, representing 46% of the world population. Overall minimal prevalence of HAE in the AP region was 0.02/100,000 population, with significant heterogeneity across different centers. Only one-half and one-third had registered on-demand and prophylactic medications, respectively. Few had patient support groups (58%) or regional guidelines (33%), and their existence was associated with the availability of HAE-specific medications. Availability of C1-inhibitor level testing was associated with a lower age at HAE diagnosis (P = .017). CONCLUSIONS: Hereditary angioedema in the AP differs from that in Western countries. Hereditary angioedema-specific medications were registered in only a minority of countries and territories, but those with patient support groups or regional guidelines were more likely to have better access. Asia Pacific-specific consensus and guidelines are lacking and urgently needed.

Inflammatory Arthritis Among Military Servicemen From a Rheumatology Center in Singapore.

INTRODUCTION: Musculoskeletal disorders are one of the most common reasons military servicemen seek medical care during their line of duty. This study aims to review the clinical profile and outcomes of military personnel with inflammatory arthritis (IA) referred to a specialist rheumatology center in Singapore. MATERIALS AND METHODS: Consecutive new case referrals from the Singapore Armed Forces medical centers during the study period January 1, 2010, to December 31, 2019, were retrospectively studied. RESULTS: There were 123 referrals, comprising 112 (91.1%) males, with the majority being Chinese (110, 89.4%). The mean age was 25.5 ± 11.1 years. The most common diagnoses were gout (including chronic tophaceous gout; 34, 27.6%), spondyloarthritis (18, 14.6%), palindromic rheumatism (8, 6.5%), rheumatoid arthritis (4, 3.3%), and juvenile idiopathic arthritis (4, 3.3%). Among servicemen with gout, all were male, the majority (31, 91.3%) were Chinese, and mean age was 34.1 ± 8.8 years. Mean body mass index (BMI) was 27.5 ± 3.9 kg/m2, of which 41.2% had moderate-risk and 47.1% high-risk BMI for cardiovascular disease and diabetes mellitus (DM). Comorbidities included hyperlipidemia (14), hypertension (6), and type 2 DM (3). Urate lowering therapy was initiated in 27 (79.4%) patients, comprising allopurinol (85.2%), probenecid (11.1%), and their combination (3.7%). One patient developed allopurinol-induced hepatitis; none had severe cutaneous adverse reactions. Among the remaining patients with IA, conventional synthetic disease-modifying antirheumatic drugs (DMARDs) used were sulfasalazine (8), methotrexate (4), hydroxychloroquine (4), and leflunomide (2). Biologic DMARDs used in five patients comprised adalimumab (3) and golimumab (2). CONCLUSION: Servicemen with IA and good functional status can still be physically fit and deployable into certain combat and service support vocations. This will optimize manpower resources in military organizations with a shrinking young workforce.

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. Groups A and B were also invited to complete a questionnaire survey on post-vaccination reactions, and blood sampling pre-vaccination and 1 h after the first dose of the BNT162b2 vaccine to measure immunoglobulin (Ig) G, IgM and IgE antibodies to the Pfizer BNT162b2 vaccine via ELISA assays immobilised with the BNT162b2 vaccine, as well as levels of allergic cytokines interleukin (IL)-4 and IL-33, complement C5a and the endothelial activation marker intercellular adhesion molecule-1 (ICAM-1). Groups A and B comprised 62 (20.5%) patients each. In Group A, two subjects (3.2%) with equivocal IDT results tolerated both doses of the BNT162b2 vaccine without major allergic reactions. The remaining 60 (96.8%) in Group A and 62 (100%) in Group B completed both doses of BNT162b2 vaccination without major adverse reactions. Among the 99 who completed the questionnaire survey, 13 (13%) patients reported mild allergic reactions after the first dose of the vaccine. Immunoglobulin (Ig) G and M antibodies, but not IgE antibodies to the Pfizer BNT162b2 vaccine were detected in 67 subjects prior to vaccination. The presence of anti-Pfizer BNT162b2 IgG and IgM prior to vaccination did not result in major allergic reactions nor increases in Th2-related cytokines (IL-4, IL-33), complement activation products (C5a) or endothelial activation (ICAM-1). The majority of those with suspected reactions to non-COVID-19 polysorbate-containing vaccines tolerated the BNT162b2 vaccine. Excipient skin tests for PEG and polysorbate prior to vaccination are unnecessary.

Asia Pacific perspectives on the second year of the COVID-19 pandemic: A follow-up survey.

BACKGROUND: The Coronavirus disease 2019 (COVID-19) pandemic is currently in its third year. This follow-up survey was commissioned by the Asia Pacific Association of Allergy Asthma and Clinical Immunology (APAAACI) Task Force on COVID-19 to compare and contrast changes in the epidemiology, clinical profile, therapeutics and public health measures of the pandemic in the Asia Pacific region. METHODS: A questionnaire-based survey comprising 32 questions was electronically sent out to all 15 member countries of APAAACI using Survey Monkey® from 1 December 2021 to 28 February 2022. RESULTS: Seventeen responses were received from 14/15 (93.4%) member countries and 3 individual members. Mild-to-moderate COVID-19 predominated over severe infection, largely contributed by COVID-19 vaccination programmes in the region. The incidence of vaccine adverse reactions in particular anaphylaxis from messenger ribonucleic acid (mRNA) vaccines was no longer as high as initially anticipated, although perimyocarditis remains a concern in younger males. Novel therapeutics for mild-to-moderate disease including neutralizing antibodies casirivimab/imdevimab (REGEN-COV®) and sotrovimab (Xevudy®), anti-virals Paxlovid® (nirmatrelvir and ritonavir) and Molnupiravir pre-exposure prophylaxis for high-risk persons with Tixagevimab and Cilgavimab (Evusheld) are now also available to complement established therapeutics (e.g., remdesivir, dexamethasone and baricitinib) for severe disease. In the transition to endemicity, public health measures are also evolving away from containment/elimination strategies. CONCLUSIONS: With access to internationally recommended standards of care including public health preventive measures, therapeutics and vaccines among most APAAACI member countries, much progress has been made over the 2-year period in minimizing the morbidity and mortality from COVID-19 disease.

Comparing hospital-resource utilization by an enhanced pneumonia surveillance programme for COVID-19 with pre-pandemic pneumonia admissions - a Singaporean hospital's experience.

Introduction. During the early days of coronavirus disease 2019 (COVID-19) in Singapore, Tan Tock Seng Hospital implemented an enhanced pneumonia surveillance (EPS) programme enrolling all patients who were admitted from the Emergency Department (ED) with a diagnosis of pneumonia but not meeting the prevalent COVID-19 suspect case definition.Hypothesis/Gap Statement. There is a paucity of data supporting the implementation of such a programme.Aims. To compare and contrast our hospital-resource utilization of an EPS programme for COVID-19 infection detection with a suitable comparison group.Methodology. We enrolled all patients admitted under the EPS programme from TTSH's ED from 7 February 2020 (date of EPS implementation) to 20 March 2020 (date of study ethics application) inclusive. We designated a comparison cohort over a similar duration the preceding year. Relevant demographic and clinical data were extracted from the electronic medical records.Results. There was a 3.2 times higher incidence of patients with an admitting diagnosis of pneumonia from the ED in the EPS cohort compared to the comparison cohort (P<0.001). However, there was no significant difference in the median length of stay of 7 days (P=0.160). Within the EPS cohort, stroke and fluid overload occur more frequently as alternative primary diagnoses.Conclusions. Our study successfully evaluated our hospital-resource utilization demanded by our EPS programme in relation to an appropriate comparison group. This helps to inform strategic use of hospital resources to meet the needs of both COVID-19 related services and essential 'peace-time' healthcare services concurrently.