Search

Adverse drug reactions are more common in geriatric patients than in younger patients, but there have been insufficient studies concerning the epidemiology or burden of drug allergy labels in geriatric patients. We prospectively investigated the prevalence and outcomes of geriatric patients with drug allergy labels in a cohort of hospitalised patients.Patients admitted to a regional hospital over a 6-month period were recruited for this study. All patients with drug allergy labels were prospectively followed until discharge; clinical data were anonymously extracted for analyses. Patients were categorised into either geriatric (aged ≥65 years) or non-geriatric (aged65 years) groups. Demographic characteristics, clinical outcomes, and prevalences of drug allergy labels were compared between groups.There were 4361 admissions involving 3641 patients during the 6-month study period. Overall, 492 patients (13.5%) had drug allergy labels, consisting of 151 non-geriatric patients (30.7%) and 341 geriatric patients (69.3%). The prevalence of drug allergy labels did not significantly differ between geriatric and non-geriatric patients (13.5% vs 13.5%, P=0.976). Significantly more patients in the geriatric group had drug allergy labels to cardiovascular system drugs (15.5% vs 4.6%, P=0.001). Geriatric patients had a significantly lower rate of direct discharge from the hospital (73.0% vs 88.1%, P0.001) and required transfers to convalescent or rehabilitation care for further management.More than 13% of hospitalised geriatric patients had drug allergy labels. The leading causes of drug allergy labels were similar between geriatric and non-geriatric patients. Geriatric patients with drug allergy labels had significantly more labelled allergies to cardiovascular system drugs and adverse clinical outcomes.

Objectives Using a centralized electronic database, we investigated the risk of cervical neoplasia (CN) and progression of cervical intraepithelial neoplasia (CIN) among patients with spondyloarthritis (SpA) receiving disease-modifying antirheumatic drugs (DMARDs). Method A total of 951 patients with SpA were reviewed. Incidence and progression of CN and clinical data including age, ethnicity, smoking and drinking status, dates of first and last follow-up, history of psoriasis, inflammatory bowel disease, medications used, mean dose and duration of medications, and comorbidities were reviewed. Cox regression models were used to evaluate the individual risk of DMARDs with CN and the risk of CIN progression. Results During a mean follow-up duration of 9.2 ± 5.9 years, 34 patients had developed CN, which translates to an incidence for development of CN in patients with SpA of 3.9 per 1000 patient-years. Univariate Cox regression analyses showed no differences in clinical characteristics (psoriasis hazards ratio [HR] = 0.92, p = 0.82; inflammatory bowel disease HR = 0.05, p = 0.61; diabetes mellitus HR = 2.82, p = 0.21; chronic kidney disease HR = 0.39, p = 0.35) and medications exposure (sulfasalazine HR = 0.49, p = 0.30; methotrexate HR = 0.52, p = 0.11; leflunomide HR = 0.52, p = 0.37; adalimumab HR = 0.83, p = 0.80; certolizumab HR = 0.05, p = 0.74; etanercept HR = 0.40, p = 0.36; golimumab HR = 0.05, p = 0.32; infliximab HR = 0.05, p = 0.39; secukinumab HR = 1.00, p = 1.00; ustekinumab HR = 0.05, p = 0.78) between patients who had and had not develop CN during the study period. Progression of CIN was independently associated with higher grades of CIN lesion (HR = 6.20; p = 0.05). Conclusions There was low risk of development and progression of CN in patients with SpA on conventional or biologic DMARD therapy.

Background Pneumocystis jiroveci pneumonia (PJP) is an opportunistic infection affecting immunocompromised individuals. However, evidence regarding the burden and effectiveness of prophylaxis among rheumatic patients remains limited. Delineating the epidemiology and efficacy of prophylaxis among rheumatic patients is urgently needed. Methods We performed a territory-wide cohort study of rheumatic patients in Hong Kong. All patients with a diagnosis of anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV), immune-mediated myositis (IMM), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), or spondyloarthritis (SpA) between 2015 and 2019 were included. Prevalence, frequency of prophylaxis and mortality of PJP were calculated. Number needed to treat (NNT) analysis was also performed. Results Out of 21,587 patients (54% RA, 25% SLE, 13% SpA, 5% IMM, 2% AAV and 1% SSc), 1141 (5.3%) patients were prescribed PJP prophylaxis. 48/21,587 (0.2%) developed PJP. No patients who developed PJP received prophylaxis prior to infection. The incidence of PJP was highest among SSc, AAV, and IMM patients. Among these diseases, the majority of PJP occurred while patients were on glucocorticoids at daily prednisolone-equivalent doses of 15 mg/day (P15) or above. PJP prophylaxis was effective with NNT for SSc, AAV and IIM being 36, 48 and 114 respectively. There were 19 PJP-related mortalities and the mortality rate was 39.6%. Conclusion PJP is an uncommon but important infection among rheumatic patients, PJP prophylaxis is effective and should be considered in patients with SSc, AAV and IMM, especially those receiving glucocorticoid doses above P15.

Background: Cardiovascular (CVS) diseases are the leading cause of death worldwide and patients with rheumatic diseases have an increased CVS. CVS risk factors and CVS events are common in spondyloarthritis (SpA). Delineating the CVS risk in patients with SpA and identifying modifiable risk factors would be useful. Methods: Patients with SpA and patients with non-specific back pain (NSBP) were identified in rheumatology and orthopedics clinics, respectively. Clinical information and CVS events were retrieved. Baseline characteristics and incidence rates of CVS events were compared between two groups of patients using an age- and sex-matched cohort. Propensity score adjustment and Cox regression analysis were performed to determine the CVS risk associated with SpA. Results: A total of 5046 patients (SpA 2616 and NSBP 2430) were included from eight centers. Over 56,484 person-years of follow up, 160 strokes, 84 myocardial infarction (MI) and 262 major adverse cardiovascular events (MACE) were identified. Hypercholesterolemia was more prevalent in SpA (SpA 34.2%, NSBP 28.7%, p Conclusion: SpA is an independent CVS risk factor. Anti-tumor necrosis factor (TNF) drugs were associated with a reduced CVS risk in these patients.

Objective: To investigate the associations between age and clinical and radiological disease activities in axial SpA. Methods: One hundred and twenty-one patients fulfilling the Assessment of SpondyloArthritis International Society Classification Criteria for axial SpA were included in analyses. Patient demographics, disease activity and radiographic scores, as well as magnetic resonance imaging (MRI) with diffusion weighted imaging derived apparent diffusion coefficient values (DWI(ADC)), were compared between patients aged > 40 and [Formula: see text] 40 years at a cross-sectional level. Variables with significant differences in univariate analyses were used as dependent variables in multivariate linear regression models adjusted for potential confounding/contributing factors. Results: Multivariate analysis showed that increasing age was significantly associated with higher Bath Ankylosing Spondylitis Functional Index (B = 0.04, p < 0.01) and Bath Ankylosing Spondylitis Metrology Index scores (B = 0.04, p < 0.01); as well as higher modified Stoke Ankylosing Spondylitis Spine Score (B = 0.41, p < 0.01). On MRI, increasing age was associated with a lower DWI(ADC) (B = (-0.01), p < 0.01) of the SI joints, but higher DWI(ADC) values of the axial spine (B = 0.01, p = 0.01). Conclusion: Increasing age in SpA was associated with greater functional impairment and structural damage, more inflammation of the axial spine, but less inflammation of the SI joints. Our findings are consistent with the traditional belief that SpA is an “ascending disease” and highlights the importance of different modalities of MRI in the diagnosis and disease monitoring of SpA.

Purpose of review Drug allergy management has previously not been emphasized in the elderly. However, the geriatric population poses several unique characteristics, challenges for drug allergy testing and considerations in the management. Especially in the era of COVID-19, the elderly population is a vulnerable cohort and reviewing the management during this unprecedented time is both timely and relevant. Recent findings In recent years, larger scale studies focusing on the epidemiology and prevalence trends of drug allergies among older adults has been summarized in this review. Emphasis on anaphylaxis in the older adults has been studied. Summary There are many implications of these findings. Epidemiological studies are useful in realizing the burden and spectrum of drug allergies on our healthcare system. It has allowed us to identify certain barriers in drug allergy management and develop ways to overcome these challenges through. Lastly, we have proposed an approach to drug allergy management based on previous studies as well as from our perspective and local experience.

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.

Background Anaphylaxis has been increasing in developed countries but there is very little published data on the burden of anaphylaxis and the pattern of adrenaline autoinjector (AAI) prescription from Asia. We aim to determine the incidence rates of anaphylaxis and prescription rates of AAI over the past decade in Hong Kong. Methods Using a centralized electronic database of Hong Kong’s sole public-funded healthcare provider, we obtained and analysed all patients between 2009 and 2019 with physician-reported diagnosis of anaphylaxis. Incidence rates were calculated using population statistics as the denominator. Patients’ prescriptions on discharge were collected to determine the AAI prescription rates. Results The overall 10-year estimated incidence rate of anaphylaxis was 3.57 per 100,000 person-years. An increasing trend over time across both paediatric and adult populations from 2009 to 2014 was found, which remained stable until 2019. This was more marked among the paediatric population (paediatric vs adult incidence rate ratio in 2019: 3.51 [95% CI 1.12–2.66] vs 1.82 [95% CI 1.05–1.60]). There was an overall increasing rate of AAI prescription for patients admitted for anaphylaxis, but the overall AAI prescription rate was less than 15% and was significantly less likely to be prescribed for the adult compared to paediatric patients (36.5% vs. 89.4%, p Conclusions An increasing trend of anaphylaxis incidence rates over the past decade is evident in Asian populations, with a discrepantly low rate of AAI prescription, particularly in the adult patients.

International audience; Background: The issues and challenges in the diagnosis of drug allergy/hypersensitivity among children and adults in Asia are likely to be different from non-Asian countries.Objective: To study the diagnostic modalities used in the evaluation and management of drug allergy/drug hypersensitivity reactions (DHRs) among member societies of the Asia Pacific Association of Allergy, Asthma and Clinical Immunology (APAAACI).Methods: A questionnaire comprising 41 questions was circulated electronically to member societies and individual members of APAAACI between January 23, 2020 and March 6, 2020.Results: Twenty-six respondents from 15 member societies and 1 individual member responded. European DHR guidelines were most commonly used. Skin prick and intradermal testing was used by 100%, with only 60% having access to commercial penicillin skin test reagents. In vitro-specific IgE tests were used by 75%, and basophil activation test by 56.3% for immediate DHR. Patch tests were used by 75% in contrast to lymphocyte transformation tests by 25% for nonimmediate DHR. Drug provocation tests were used by 68.8%, the most common indication being to exclude hypersensitivity where history/symptoms were not suggestive of drug hypersensitivity/allergy (93.3%). Human leukocyte antigen (HLA) genotype testing was mandatory among 25% respondents before new carbamazepine prescriptions, and 8.3% for allopurinol prescriptions.Conclusions: There was increased use of skin testing for iodinated contrast media hypersensitivity and patch testing for nonimmediate DHR. HLA genotype testing prior to new carbamazepine, allopurinol and abacavir prescriptions remain variable despite strong associations for severe cutaneous adverse reactions with Asian ethnicity. Results of this survey form a useful framework for developing educational and training needs and for improving access to drug allergy diagnostic and treatment modalities across APAAACI member societies.

Vaccination of egg-allergic individuals has been a historical concern, particularly for influenza and measles-mumps-rubella-varicella vaccines that are developed in chicken egg embryos or chicken cell fibroblasts. The egg proteins in these vaccines were believed to trigger an immediate allergic reaction in egg-allergic individuals. However, recently published international guidelines have updated their recommendations and now state that these vaccines can be safely administered to egg-allergic individuals. This joint consensus statement by the Hong Kong Institute of Allergy and the Hong Kong Society for Paediatric Immunology Allergy & Infectious Diseases summarises the updates and provides recommendations for local general practitioners and paediatricians. Hong Kong Institute of Allergy and Hong Kong Society for Paediatric Immunology Allergy & Infectious Diseases joint consensus statement 2018 on vaccination in egg-allergic patients Background.

Objective The aim of this study was to determine the prevalence and associated factors for uveitis in ethnic Chinese patients with axial spondyloarthritis (SpA) and ankylosing spondylitis (AS). Methods This was a cross-sectional study. Patients fulfilling the Assessment of SpondyloArthritis international Society axial SpA criteria were recruited consecutively from 3 rheumatology centers in Hong Kong from March 2014 to July 2017. Clinical and biochemical parameters were collected. History of uveitis was inquired from both history and medical records. All patients received lumbosacral spine x-rays and whole-spine and sacroiliac joint magnetic resonance imaging. Patients were defined as axial SpA if they fulfilled the Assessment of SpondyloArthritis international Society criteria and AS if they fulfilled the modified New York criteria. Clinical and radiological findings were compared between patients with and without uveitis in the 2 groups. Factors associated with uveitis were identified with univariate analyses and multivariate logistic regression analyses. Results Among 252 patients, 67 patients (26.6%) had a history of uveitis. The male-to-female ratio was 55.4 to 44.6. Disease duration was 12.3 ± 11.7 years. In the axial SpA group, multivariate regression showed that older age (odds ratio [OR], 1.05; p = 0.01), human leukocyte antigen B27 positivity (OR, 11.79; p = 0.01), and history of inflammatory bowel disease (OR, 9.74; p = 0.04) were positively associated with uveitis. In the AS group, multivariate regression showed that back pain duration (OR, 1.05; p = 0.01) and male sex (OR, 3.46; p = 0.03) were associated with uveitis. Conclusions Axial SpA represents a spectrum of diseases. Its clinical associations with uveitis should be distinguished from those of traditional AS.

Antibody deficiencies can be either primary or secondary, leading to significant morbidity and mortality without appropriate management. Secondary antibody deficiency can be due to various diseases or iatrogenic causes, especially with the use of immunosuppressive agents such as B-cell depleting therapies. Unlike its primary counterpart, little is known regarding the management of secondary antibody deficiency and it remains an underappreciated entity. This is a growing concern with the growing numbers of patients on various immunosuppressant therapies and increasing survivors of autoimmune diseases and haematological malignancies. In this report, we review the diagnosis and management of secondary antibody deficiency, especially after rituximab-induced hypogammaglobulinemia.

BackgroundAcinetobacter spp. is an important cause of peritoneal dialysis (PD)-related peritonitis, but studies on Acinetobacter peritonitis have been scarce. In view of the rising concern of carbapenem-resistant Acinetobacter (CRA) and multidrug-resistant Acinetobacter (MDRA) infections, we conducted this study on the incidence of Acinetobacter peritonitis and the impact of CRA and MDRA on its outcome.MethodsWe retrospectively evaluated the clinical characteristics, prevalence, antibiotic sensitivity patterns, outcomes, and factors associated with treatment failure over the past 16 years in our patients with Acinetobacter PD-related peritonitis.ResultsOut of 2,389 episodes of peritonitis, there were 66 episodes (3%) of Acinetobacter peritonitis occurring in 59 patients. Twelve episodes were caused by MDRA (18%), of which 5 were CRA (8%). There was a progressive increase in the incidence of MDRA and CRA infections over the study period. Most isolates were sensitive to sulbactam combinations (ampicillin-sulbactam [95.4%] and cefoperazone-sulbactam [93.9%]), aminoglycosides (amikacin [92.4%], tobramycin [90.9%], and gentamicin [89.4%]), and carbapenems (imipenem [92.2%]). There was 1 case of relapse. Fifteen episodes resulted in catheter removal (23%), and 7 patients died (11%). Hypoalbuminemia (odds ratio [OR] = 0.85, p = 0.006) and carbapenem resistance (OR = 18.2, p = 0.049) were significantly associated with higher rates of treatment failure.ConclusionBoth carbapenem resistance and hypoalbuminemia were significantly associated with treatment failure. Up to 80% of peritonitis episodes by CRA resulted in catheter loss or mortality. Sulbactam combinations and/or aminoglycosides remained effective for the majority of Acinetobacter isolates. There seemed to be an increasing relative incidence of MDRA and CRA infections over the past 16 years.

Background Omega-5-gliadin (O5G) allergy, also known as wheat-dependent exercise-induced anaphylaxis, is commonly reported in the Western, but not Asian, populations. Although significant differences in O5G allergy presentation across different populations are likely but there have been no previous reports on this important topic. Objective To report on the prevalence and characteristics of O5G allergy in Hong Kong (HK) compared with the United Kingdom (UK). Methods O5G allergy patients attending Queen Mary Hospital (HK cohort), and Guy's and St Thomas' Hospital, London (UK cohort) were studied and compared. Results A total of 46 O5G allergy patients (16 HK; 30 UK) were studied. In the HK cohort, 55% of all patients previously labeled as "idiopathic anaphylaxis" were diagnosed with O5G allergy. Exercise was the most common cofactor in both cohorts, followed by alcohol and nonsteroidal anti-inflammatory drugs (NSAID). A higher proportion of the HK cohort reported NSAID as a cofactor (13% vs. 0%, p = 0.048). In the HK cohort, more patients presented with urticaria and cardiovascular manifestations (100% vs. 77%, p = 0.036; 100% vs. 70%, p = 0.015, respectively); the range of presentation was more diverse in the UK cohort. In HK fewer patients adhered to wheat avoidance (50% vs. 87%, p = 0.007) and more patients avoided cofactors only (44% vs. 10%, p = 0.008). Conclusion O5G allergy appears relatively underdiagnosed in HK. Urticaria and cardiovascular manifestations are common; NSAID plays an important role as a cofactor and patients are less concordant with dietary avoidance measures than in the Western population.

Introduction: Beta-lactams (BL) are the most frequently reported drug allergy, but the vast majority of patients are found not to be genuinely allergic after evaluation. Few studies have investigated the clinical predictors of genuine BL allergy, and the prevalence in hospitalized Chinese patients is unknown. Methods: Patients admitted to a tertiary hospital in Hong Kong (HK) were analyzed to identify the prevalence and factors associated with the presence of BL allergy labels among hospitalized Chinese patients. A combined cohort of patients having completed allergy investigation for suspected BL allergies in the United Kingdom (UK) and HK were analyzed to identify predictors of genuine allergy. Results: The prevalence of BL allergy labels in hospitalized HK Chinese was 5%, which was associated with female gender and concomitant non-BL antibiotic allergy labels. The rate of genuine BL allergy patients referred for suspected allergies in the UK and HK cohort was only 14%. History of anaphylaxis and interval of less than a year since the index reaction were independent clinical predictors of genuine BL allergy. The negative predictive value of penicillin skin testing was 90%, confirming the need for drug provocation testing after negative skin testing. There was a high rate of confirmed piperacillin-tazobactam allergy. Discussion: The estimated true prevalence of genuine BL allergy in hospitalized HK Chinese is around 0.5%. This high rate of BL mislabeling highlights the need for comprehensive allergy evaluation and screening. History of anaphylaxis and duration since the index reaction are important predictors of genuine allergy. Piperacillin-tazobactam allergy may pose a unique challenge in this population with a high prevalence of suspected allergies, surging antibiotic resistance, and lack of testing available. Keywords: Allergy, Antibiotics, Beta-lactams, Chinese, Drug, Epidemiology, Hypersensitivity, Penicillins, Predictors, Prevalence

Background:Pneumocystis jiroveci pneumonia (PJP) is an opportunistic infection affecting immunocompromised individuals. Due to its high mortality, PJP prophylaxis is commonly recommended for many immunocompromising conditions. However, evidence regarding the burden and role of prophylaxis in PJP among rheumatic patients remains limited. There is lack of consensus for when and for whom to initiate prophylaxis. Delineating the epidemiology, predictors of mortality and efficacy of prophylaxis in PJP among rheumatic patients is urgently needed.Objectives:To delineate the epidemiology of PJP, identify predictors of mortality and evaluate the usefulness of prophylaxis in rheumatology patients.Methods:We performed a big-data cohort study based on the territory-wide healthcare database of the Hong Kong Hospital Authority. All patients with a diagnosis of anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV), immune-mediated myositis (IMM), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), or spondyloarthritis (SpA) between 2015-2019 were included. PJP were identified based on physician diagnosis and/or positive microbiological results from deep respiratory tract specimens. Prophylaxis was defined as prescription of a prophylactic dose of co-trimoxazole for at least 2 weeks and/or inhaled pentamidine. Prevalence of PJP, prophylaxis and mortality among rheumatic patients were calculated. Demographics, blood parameters and immunosuppressants use was also collected for multivariate analysis. Number needed to treat (NNT) analysis was performed based on absolute risk reduction of PJP in patients with and without prior PJP prophylaxis.Results:A total of 21,587 unique rheumatic patients were analysed (54% RA, 25% SLE, 13% SpA, 5% IMM, 2% AAV and 1% SSc). Between 2015-2019, 1141 (5.3%) patients were prescribed PJP prophylaxis and 48 (0.2%) developed PJP. None of those patients who developed PJP had received prophylaxis prior to infection. The risk of PJP was highest among SSc (1.8%), AAV (1.4%) and IMM (0.7%) patients, with NNT of SSc 36, AAV 48 and IMM 114. Within these disease entities, the majority of PJP occurred at prednisolone dose of 15mg/day (P15) or above (100% in SSc and IIM, 66.7% in AAV). Overall, PJP was associated with a mortality-rate of 39.6%. Glucocorticoid dose (daily prednisolone dose equivalent 29.1±23.5mg vs 11.4±7.2mg, P9/L vs 0.90x109/L, P= 0.04) at PJP diagnosis were associated with PJP mortality in rheumatic patients.Conclusion:PJP is an uncommon but important infection in rheumatic patients associated with significant mortality. PJP prophylaxis is effective and should be considered in patients with SSc, AAV and IMM, especially in those receiving a steroid dose above P15.Disclosure of Interests:None declared

Background:Cardiovascular (CVS) diseases are the leading cause of death worldwide and patients with rheumatic diseases have an increased CVS risk including stroke and myocardial infarction (MI) (1-3). CVS risk factors and CVS events are common in SpA (4). Delineating the CVS risk and the association with medications in patients with SpA would be useful.Objectives:The objective of this study was to delineate the CVS risk and the association with medications in patients with SpA.Methods:Patients with SpA and patients with non-specific back pain (NSBP) were identified in rheumatology and orthopedics clinics respectively. Clinical information and CVS events were retrieved. Incidence rates were calculated. Association analysis was performed to determine the CVS risk of SpA and other modifiable risk factors.Results:A total of 5046 patients (SpA 2616 and NSBP 2430) were included from eight centers. Over 56 484 person-years of follow-up, 160 strokes, 84 MI and 262 major adverse cardiovascular events (MACE) were identified. Hypercholesterolemia was more prevalent in SpA (SpA 34.2%, NSBP 28.7%, PConclusion:SpA is an independent CVS risk factor. Anti-TNF drugs were associated with a reduced CVS risk in these patients.References:[1]Crowson CS, Liao KP, Davis JM, 3rd, Solomon DH, Matteson EL, Knutson KL, et al. Rheumatoid arthritis and cardiovascular disease. Am Heart J. 2013;166(4):622-8 e1.[2]Verhoeven F, Prati C, Demougeot C, Wendling D. Cardiovascular risk in psoriatic arthritis, a narrative review. Joint Bone Spine. 2020;87(5):413-8.[3]Liew JW, Ramiro S, Gensler LS. Cardiovascular morbidity and mortality in ankylosing spondylitis and psoriatic arthritis. Best Pract Res Clin Rheumatol. 2018;32(3):369-89.[4]Molto A, Etcheto A, van der Heijde D, Landewe R, van den Bosch F, Bautista Molano W, et al. Prevalence of comorbidities and evaluation of their screening in spondyloarthritis: results of the international cross-sectional ASAS-COMOSPA study. Ann Rheum Dis. 2016;75(6):1016-23.Disclosure of Interests:None declared.

Background: Drug allergies (DA) are immunologically mediated adverse drug reactions and their manifestations depend on a variety of drug- and patient-specific factors. The dysregulated immune system underpinning rheumatological diseases may also lead to an increase in hypersensitivity reactions, including DA. The higher prevalence of reported DA, especially anti-microbials, also restricts the medication repertoire for these already immunocompromised patients. However, few studies have examined the prevalence and impact of reported DA in this group of patients. Methods: Patients with a diagnosis of rheumatoid arthritis (RA), spondyloarthritis (SpA), or systemic lupus erythematosus (SLE) were recruited from the rheumatology clinics in a tertiary referral hospital between 2018 and 2019. Prevalence and clinical outcomes of reported DA among different rheumatological diseases were calculated and compared to a cohort of hospitalized non-rheumatology patients within the same period. Results: A total of 6081 patients (2541 rheumatology patients: 1286 RA, 759 SpA, and 496 SLE, and 3540 controls) were included. DA was more frequently reported among rheumatology patients compared to controls (23.8% vs. 13.8%, p &lt, 0.01). Antibiotics and non-steroidal anti-inflammatory drugs (NSAIDs) were the two most commonly reported categories of DA with a prevalence of 12.0% and 5.1%, respectively. Reported antibiotics allergies were more frequent in patients with RA (OR = 1.20, 95% CI = 1.02&ndash, 1.62, p = 0.03) and SLE (OR = 4.69, 95% CI = 3.69&ndash, 5.95, p &lt, 0.01), and associated with increased infection-related admissions among rheumatology patients (OR = 1.79, 95% CI = 1.09&ndash, 2.95, p = 0.02). Among the subgroup of patients referred for allergy testing, 85.7% of beta-lactam antibiotic allergy labels were found to be inaccurate and de-labelled after negative drug provocation testing. Conclusion: The prevalence of reported DA was significantly higher in rheumatology patients. Reported antibiotic allergy was associated with increased rate of infection-related admissions. However, the rate of genuine antibiotic allergy was low. Further studies are needed to guide proper assessment of reported DA and impact of comprehensive allergy testing in this group of patients.

This cross-sectional study examines the reported penicillin allergies and sensitization to skin-testing compounds benzylpenicilloyl polylysine and minor determinants among patients in Hong Kong., Key Points Question What are the prevalence, incidence, and sensitization patterns of β-lactam antibiotic allergy in Hong Kong? Findings In this cross-sectional study of 7 184 271 patient records, the prevalence of reported β-lactam antibiotic allergy was 2.0% and the cumulative incidence was 107 per 100 000 population. Only 13.8% of patients who underwent skin testing had positive results, but 47% had high rates of sensitization to the reagent benzylpenicilloyl polylysine or a minor determinant (benzylpenicilloate). Meaning These findings suggest that benzylpenicilloyl polylysine and a minor determinant (benzylpenicilloate) should be included in β-lactam antibiotic allergy skin testing for the large and rapidly growing burden of β-lactam antibiotic allergies reported among patients in Hong Kong., Importance Allergy to β-lactam antibiotics is one of the most frequently reported drug reactions, but epidemiological data in Chinese populations are lacking. Ethnic- and region-specific sensitization patterns of skin testing for β-lactam antibiotic allergy are also unknown. Objective To identify the prevalence, 1-year incidence, and sensitization patterns of β-lactam antibiotic allergy in patients in Hong Kong. Design, Setting, and Participants This cross-sectional study obtained territorywide, anonymized electronic patient data from the Clinical Management Systems of the Hospital Authority, the sole publicly funded health care system in Hong Kong with facilities in 7 regions (Hong Kong East, Hong Kong West, Kowloon Central, Kowloon East, Kowloon West, New Territories East, and New Territories West). All referrals to Queen Mary Hospital for β-lactam antibiotic allergy testing from January 1, 2018, to December 31, 2019, were also analyzed for sensitization patterns. Main Outcomes and Measures Prevalence and cumulative incidence of β-lactam antibiotic allergy reported in Hong Kong, and sensitization patterns according to β-lactam antibiotic allergy skin testing. Results Complete records of 7 184 271 unique patients were analyzed, with a men to women ratio of 1:1.2 and with a median age of 44 years. The prevalence of physician-reported β-lactam antibiotic allergy was 2.0%, and the cumulative incidence was 107 per 100 000 population. Of the 34 402 new drug allergies reported in 2018, 8032 (23.3%) were β-lactam antibiotic allergies. Three hundred fifty-five patients with reactions suggestive of β-lactam antibiotic allergy underwent skin testing, and only 49 (13.8%; 95% CI, 10.64%-17.90%) of them had positive test results. Of these 49 patients, 14 (28.6%; 95% CI, 18.35%-44.49%) had selective reaction and 35 (71.4%; 95% CI, 59.84%-85.27%) had nonselective reaction. The sensitization rate to either benzylpenicilloyl polylysine or a minor determinant (benzylpenicilloate) was 47.0% (n = 23; 95% CI, 34.85%-63.21%), with 10 patients monosensitized to benzylpenicilloyl polylysine only (20.4%; 95% CI, 11.74%-35.48%) and 5 to benzylpenicilloate only (10.2%; 95% CI, 4.45%-23.42%). Conclusions and Relevance Results of this study suggest that patients in Hong Kong with β-lactam antibiotic allergy had much higher rates of monosensitization to benzylpenicilloyl polylysine and benzylpenicilloate, making these reagents essential in β-lactam antibiotic skin tests. Such a finding warrants future studies into whether this sensitization is specific to ethnicity or region.

Background: The presence of ⩾3 corner inflammatory lesions has been proposed as the definition of a positive spinal magnetic resonance imaging (MRI) for axial spondyloarthritis (axSpA), but subsequent studies showed inconclusive findings. Our objective was to evaluate whether locations of corner inflammatory lesions (CILs) would affect the diagnostic utility of MRI in axSpA. Method: Two groups were consecutively recruited from eight rheumatology centers in Hong Kong. The ‘axSpA’ group included 369 participants with a known diagnosis of axSpA. The ‘non-specific back pain’ (NSBP) control group consisted of 117 participants. Clinical, biochemical, and radiological parameters were collected and all patients underwent MRI of the spine and sacroiliac joints. CILs were assessed based on their locations (cervical, thoracic or lumbar) to determine the optimal cutoff for diagnosis. Results: The cutoff of ⩾5 whole spine CILs (W-CILs) and ⩾3 thoracic spine CILs (T-CILs) had comparable specificity to MRI sacroiliitis. Of 85/369 axSpA patients without sacroiliitis on conventional radiograph or MRI, 7 had ⩾5 W-CILs and 11 had ⩾3 T-CILs. Incorporating the proposed cutoffs into Assessment of SpondyloArthritis international Society axSpA criteria, ⩾5 W-CILs and ⩾3 T-CILs had similar performance when added to the imaging criteria for sacroiliitis (sensitivity 0.79 versus 0.80, specificity 0.92 versus 0.91). Conclusion: Spinal MRI provided little incremental diagnostic value in unselected axSpA patients. However, in patients without sacroiliitis on MRI or radiographs, 8–13% might be diagnosed by spinal MRI. Thoracic and whole spine MRI had similar diagnostic performance using the proposed cutoff of ⩾5 W-CILs and ⩾3 T-CILs.

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.

Background: There are marked geographical as well as temporal differences in patient sensitization profiles to β-lactams (BL). Objective: To determine the utility of skin test reagents and identify a cohort of patients where skin testing can be safely omitted in a cohort of patients referred to a UK tertiary referral center. Methods: A retrospective study of the clinical characteristics of 1092 patients referred for BL allergy testing was analyzed using multivariate regression analysis. The effectiveness of skin test reagents was also evaluated. Results: Multivariate logistic regression identified that a history of anaphylaxis (odds ratio [OR] 10.98, P =.001) and the patients' recall of the index drug (apart from ampicillin and meropenem, OR 3.51-12.43, P

Melioidosis is often considered an exotic and uncommon disease in most parts of the world. However it is an endemic disease in Southeast Asia and Northern Australia with an expanding distribution. Melioidosis can involve almost any organ and can deteriorate rapidly. In this report, we describe a rapidly fatal case of a mycotic aneurysm associated with melioidosis despite aggressive antibiotic therapy. The morbidity and mortality of this uncommon complication remains high despite prompt diagnosis and treatment. Especially when treating persistent/recurrent melioidosis, the physician's caution to the development of mycotic aneurysms is imperative so that early treatment and surgical intervention may be considered.

The transition of HIV and AIDS from a death sentence to a chronic disease has not come without problems. Rheumatologists need to be aware of the full spectrum of rheumatic diseases seen in patients with HIV and AIDS, and know the best strategies for disease management.

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.

INTRODUCTION Immunoglobulin G4-related disease remains an under-recognised and evolving disease. Local data are sparse and previous publications have been limited to individual case reports or case series only. We conducted this study to review the clinical features, treatment practices, and factors associated with multisystem involvement in Hong Kong. We described the clinical features and treatment modalities of the largest cohort of immunoglobulin G4-related disease in our locality thus far. METHODS We retrospectively evaluated all patients with immunoglobulin G4-related disease between January 2003 and December 2015 in Queen Mary Hospital and combined this with patient data extracted from previous local publications. We analysed the clinical features, treatment practices, and factors associated with the number of organ systems involved. RESULTS A total of 104 patients (55 from Queen Mary Hospital and 49 from literature review) were identified. Patients were predominantly older men (mean [standard deviation] age, 61.9 [12.7] years; male-to-female ratio=3:1) and 94.4% had elevated pre-treatment serum immunoglobulin G4 levels. Hepatobiliary and pancreatic system (40.4%), salivary gland (33.7%), lymph node (29.8%), and eye (19.2%) were the most common organ systems involved. Lymphadenopathy was associated with glucocorticoid use (odds ratio=2.65; 95% confidence interval, 1.08-6.54; P=0.034). Pre-treatment serum immunoglobulin G4 levels correlated with the number of organ systems involved (β=0.347; P=0.004) and, specifically, more associated with patients having salivary gland involvement than those without (mean, 1109 mg/dL vs 599 mg/dL; P=0.012). CONCLUSION We identified pre-treatment serum immunoglobulin G4 to be associated with multisystem disease, especially with salivary gland involvement, highlighting its potential for disease prognostication and monitoring. Increased physician awareness and multidisciplinary efforts are required for early diagnosis and optimal management of this masquerading disease.

Background Immunoglobulin (Ig) G4-related disease (IgG4-RD) is a systemic immune-mediated disease unifying what were previously considered to be unrelated individual organ disorders. The diagnosis and treatment of this characteristic fibroinflammatory condition continues to evolve, but generally remains an under-recognised disease. Local data outside Japanese and Caucasian populations is lacking and few studies have examined factors to predict disease severity or disease prognostication. Objectives We conducted this study to review the clinical features, treatment practices and factors associated with more extensive disease involvement in Hong Kong. Methods We retrospectively evaluated all patients with IgG4-RD over the past 13 years in our centre and combined this with patient data extracted from previous local publications. We analysed the clinical features, treatment practices and factors associated with the number of organ systems involved. Results One hundred and four patients (55 from our centre and 49 from literature review) were identified. Patients were predominantly older men (mean age 61.9 years, male:female ratio 3:1). Hepatobiliary and pancreatic (40.4%), salivary gland (33.6%), lymph nodes (29.8%) and eye (19.2%) were the most common systems involved. Lymphadenopathy was associated with glucocorticoid use (OR=2.65, p=0.034). Over 90% of patients had a serum greater than 135 mg/dl and a IgG4/total IgG ratio greater than 8%. Pre-treatment serum IgG4 levels correlated with the number of organ systems involved (β=0.347, p=0.004), and specifically with salivary gland involvement (mean 1109 mg/dl vs. 599 mg/dl, p=0.012). Conclusions We identified pre-treatment serum IgG4-RD to be associated with multi-system disease, especially with salivary gland involvement, highlighting the potential for its use in disease prognostication and monitoring. The reason for this particular correlation remains uncertain but highlights the importance of screening for salivary gland involvement in all IgG4-RD patients, especially in the presence of higher serum IgG4 levels. We also describe the clinical features and treatment modalities of the largest cohort of IgG4-RD in Hong Kong thus far. Increased physician awareness and multidisciplinary efforts are required for optimal management of this masquerading disease. Future studies, especially focusing on treatment strategies within the contexts of different epidemiology and patient characteristics, are urgently needed. Disclosure of Interest None declared

Background True IgE-mediated hypersensitivity to opioids is rare and many reactions are due to direct mast cell degranulation. Opioid drug provocation testing (DPT) is the gold standard for diagnosis but is underutilized. Objective The objective of this study was to evaluate the clinical characteristics and predictors of opioid hypersensitivity, as well as outcomes of opioid DPT. Methods Patients referred for opioid DPT over the past 9 years were studied. Patient characteristics, indications for opioid use, symptoms of index reaction, and outcomes of DPT were analyzed. Association analysis was performed to study variables associated with a diagnosis of opioid hypersensitivity. Results Of the total of 98 patients referred with suspected opioid hypersensitivity, 15 (15%) were diagnosed with opioid allergy. Angioedema (odds ratio [OR]: 5.66; 95% confidence interval [CI]: 1.49-21.47; P = .011) and hypotension (OR: 5.00; 95% CI: 1.15-21.70; P = .032) were significantly more frequent in opioid allergic patients than those with a negative DPT. Patients who received opioids during anesthesia were significantly more likely to be opioid allergic (OR: 6.74; 95% CI: 2.05-22.13; P = .001). In contrast, a negative association was identified with patients who received opioids for analgesia (OR: 0.27; 95% CI: 0.08-0.86; P = .008). Conclusions Only 15% of our cohort were diagnosed with opioid allergy, emphasizing the importance of DPT in preventing erroneous overdiagnosis. Patients with a history of angioedema or hypotension as their index reaction were significantly more likely to be opioid allergic. DPT are safe when performed by experienced clinicians after risk stratification and using individualized protocols.

Objective This study aims to identify the existence of, and relationship between autoantibody clusters and clinical subsets in Chinese SLE patients. Methods Data from 1928 SLE patients from Hong Kong were analysed. Using cluster analysis, patients were grouped by autoantibodies into clusters. The frequencies of various clinical manifestations were then compared between each cluster. Separate association analyses between individual autoantibodies and clinical manifestations as well as between clinical manifestations were also performed without any prior clustering. Results Three separate autoantibody clusters were identified, each with significantly different clinical manifestations. Cluster 1 was characterized by anti-dsDNA and the greatest prevalence of renal disorder but the lowest frequencies of other clinical manifestations. Cluster 2 was represented by the predominance of anti-Smith, anti-RNP and aPL, with greater prevalence of malar rash, oral ulcers, arthritis and serositis. Cluster 3 was characterized by anti-Ro and anti-La with greater prevalence of discoid rash, photosensitivity and haematological involvement. Individual association analysis also revealed similar findings. Patients of clusters 2 and 3 were more closely related, while cluster 1 was more distinct, associated with renal disorder only and negatively associated or not associated with other manifestations. Conclusion We conclude that autoantibody clustering and clinical subsets exist in SLE patients of our locality. These clusters may be viewed as a bipolar spectrum of related autoantibody and clinical manifestations. At one end are patients with over-representation of anti-dsDNA and renal disorder, while at the other end are two distinct autoantibody clusters (anti-Sm/anti-RNP/aPL and anti-Ro/anti-La) with overlapping of other clinical manifestations.

Objective To compare the utility of Diffusion weighted imaging (DWI) with short tau inversion recovery (STIR) sequence in the diagnosis of early axial spondyloarthritis (SpA). Methods Three hundred and five patients with chronic back pain were recruited consecutively from 3 rheumatology centers. Clinical, radiological and blood parameters were recorded. Patients with back pain duration no more than 3 years were classified as having early disease. STIR sequence and DWI of the sacroiliac joints were obtained and assessed using the Spondyloarthritis Research Consortium of Canada (SPARCC) method. The Assessment in Spondyloarthritis international Society definition was used to define positive STIR and DWI. Results were compared to expert diagnosed axial SpA. Results When compared to STIR sequence, DWI had similar sensitivity (STIR 0.29, DWI 0.30) and specificity (STIR 0.97, DWI 0.92) in diagnosing sacroiliitis. However, STIR sequence had better reliability (STIR 0.78, DWI 0.61). In early disease group, DWI was not better than STIR sequence in detecting active sacroiliitis (sensitivity DWI vs STIR: 0.34 vs 0.36; specificity DWI vs STIR: 0.93 vs 0.93; positive predictive value DWI vs STIR: 0.92 vs 0.92; negative predictive value DWI vs STIR: 0.36 vs 0.37). Using the Assessment in SpondyloArthritis international Society (ASAS) classification criteria, 67/98 patients with early disease (sensitivity 0.91 specificity 0.90) and 221/305 overall (sensitivity 0.90; specificity 0.92) were classified as axial SpA. Among the expert diagnosed axial SpA patients who did not meet the ASAS criteria, only 2 had positive DWI. Conclusion DWI and STIR have similar sensitivity in diagnosing axSpA in early disease. However, the use of DWI is limited by poorer reliability when compared with STIR.

Summary Background An epidemic of severe acute respiratory syndrome (SARS) has been associated with an outbreak of atypical pneumonia originating in Guangdong Province, People's Republic of China. We aimed to identify the causative agent in the Guangdong outbreak and describe the emergence and spread of the disease within the province. Methods We analysed epidemiological information and collected serum and nasopharyngeal aspirates from patients with SARS in Guangdong in mid-February, 2003. We did virus isolation, serological tests, and molecular assays to identify the causative agent. Findings SARS had been circulating in other cities of Guangdong Province for about 2 months before causing a major outbreak in Guangzhou, the province's capital. A novel coronavirus, SARS coronavirus (CoV), was isolated from specimens from three patients with SARS. Viral antigens were also directly detected in nasopharyngeal aspirates from these patients. 48 of 55 (87%) patients had antibodies to SARS CoV in their convalescent sera. Genetic analysis showed that the SARS CoV isolates from Guangzhou shared the same origin with those in other countries, and had a phylogenetic pathway that matched the spread of SARS to the other parts of the world. Interpretation SARS CoV is the infectious agent responsible for the epidemic outbreak of SARS in Guangdong. The virus isolated from patients in Guangdong is the prototype of the SARS CoV in other regions and countries.

Background Spondyloarthritis (SpA) is an umbrella term which includes several inflammatory arthritides sharing common clinical features, such as sacroiliitis, spondylitis, peripheral arthritis/enthesitis and other extra-articular manifestations. Although typically presenting at a young age, SpA is often a relentlessly progressive disease even in this new era of biologics. In the last few years, much research has been generating on discovering new and more sensitive modalities in the use of magnetic resonance imaging (MRI) for assessing SpA. The advent of MRI has enabled clinicians to detect objective features of active inflammation, thereby allowing earlier diagnosis and more quantitative assessment of disease severity. Despite these rapid advancements, there have been few reports on examining the association between age and disease activity in SpA, especially with the use of these various new modalities of imaging. In this cross-sectional analysis, we examine the associations between age and the clinical and radiological disease activities in axial SpA using radiographs as well as different modalities of MRI. Methods One hundred and twenty one patients fulfilling the Assessment of SpondyloArthritis International Society Classification Criteria for axial SpA were included in analyses. Patient demographics, disease activity and radiographic scores, as well as magnetic resonance imaging (MRI) with diffusion weighted imaging derived apparent diffusion coefficient values ((DWI(ADC)), were compared between patients older than and younger/equal to 40 years of age at a cross-sectional level. Variables with significant differences in univariate analyses were used as dependent variables in multivariate linear regression models adjusted for potential confounding/contributing factors. Results Multivariate analysis showed that increasing age was significantly associated with higher Bath Ankylosing Spondylitis Functional Index (B=0.04, p Conclusions Increasing age in SpA was associated with greater functional impairment and structural damage, more inflammation of the axial spine, but less inflammation of the SI joints. Our findings are consistent with the traditional belief of SpA being an “ascending disease” and highlights the importance of different modalities of MRI in the diagnosis and disease monitoring of SpA. Disclosure of Interest None declared

Background DWI has been proposed for SpA diagnosis and disease monitoring1,2. The clinical correlation and effectiveness of this imaging when compared to the traditional STIR sequence is still under evaluation. Objectives To compare DWI with with clinical features, and traditional STIR sequence in detecting spinal and SI joints inflamation in SpA patients. Methods One hundred and ten patients fulfilled ASAS Axial SpA criteria were recruited consecutively from two rheumatology centers in Hong Kong. Clinical, radiological and blood parameters were collected. DWI and STIR MRI were performed simultaneously and results were scored according to the Spondyloarthritis Research Consortium of Canada (SPARCC) for comparison. The Apparent Diffusion Coefficient (ADC) values were also calculated. Results DWI showed no correlation with clinical features. When compare with STIR sequence, it correlated well with STIR sequence at the SI joints level (CC 0.76, p Conclusions Both STIR sequence and DWI perform similiarily in detecting active sacroiliitis. At spinal level, ADC values appear to be independent of other imaging/ clinical assessment and are not affected by degenerations. References Gaspersic N, Sersa I, Jevtic V, et al. Monitoring ankylosing spondylitis therapy by dynamic contrast-enhanced and diffusion-weighted magnetic resonance imaging. Skeletal Radiol. 2008 Feb; 37(2): 123–31. Sahin N, Hacibeyoglu H, Ince O, et al. Is there a role for DWI in the diagnosis of sacroiliitis based on ASAS criteria? Int J Clin Exp Med. 2015 May 15; 8(5): 7544–52. Disclosure of Interest None declared

Systemic lupus erythematosus is a complex and potentially fatal autoimmune disease, characterized by autoantibody production and multi-organ damage. By a genome-wide association study (320 patients and 1,500 controls) and subsequent replication altogether involving a total of 3,300 Asian SLE patients from Hong Kong, Mainland China, and Thailand, as well as 4,200 ethnically and geographically matched controls, genetic variants in ETS1 and WDFY4 were found to be associated with SLE (ETS1: rs1128334, P = 2.33x10 -11, OR = 1.29; WDFY4: rs7097397, P = 8.15x10 -12, OR = 1.30). ETS1 encodes for a transcription factor known to be involved in a wide range of immune functions, including Th17 cell development and terminal differentiation of B lymphocytes. SNP rs1128334 is located in the 3'-UTR of ETS1, and allelic expression analysis from peripheral blood mononuclear cells showed significantly lower expression level from the risk allele. WDFY4 is a conserved protein with unknown function, but is predominantly expressed in primary and secondary immune tissues, and rs7097397 in WDFY4 changes an arginine residue to glutamine (R1816Q) in this protein. Our study also confirmed association of the HLA locus, STAT4, TNFSF4, BLK, BANK1, IRF5, and TNFAIP3 with SLE in Asians. These new genetic findings may help us to gain a better understanding of the disease and the functions of the genes involved. © 2010 Yang et al., published_or_final_version

To the Editor: We read with interest the study of Hellquist, et al 1 showing tyrosine kinase 2 ( TYK2 ) is associated with systemic lupus erythematosus (SLE). Similar results have been reported in different Caucasian populations2,3,4, but not in a recently published Japanese study5. Interestingly, we also found TYK2 polymorphisms were not associated with SLE in Hong Kong Chinese, although subphenotype analysis revealed it may be associated with the development of photosensitivity and discoid rash. Our study was approved by the Institutional Review Board of the University of Hong Kong/Hospital Authority Hong Kong West Cluster. The study included 669 patients with SLE and 2538 controls, as reported6,7. Genotyping with the Illumina 610-Quad Human Beadchip (Illumina, San Diego, CA, USA) from 612 patients and 2193 healthy controls included 9 single-nucleotide polymorphisms (SNP) within 10 kilobases spanning TYK2 . Additional genotyping by direct sequencing on 150 patients and 345 healthy controls was performed for rs12720270, rs2304356, and rs2304255, which were not included … Address correspondence to Dr. Lau; E-mail: lauylung{at}hkucc.hku.hk