Methodical control of the difficult pediatric airway: two case reports

BACKGROUND

Management of children who present with a history of impossible mask ventilation or difficult tracheal intubation is fraught with challenges. Despite this, the "airway stress test" of an inhalational induction is frequently employed risking airway obstruction, breath holding, apnea, and laryngospasm.

CASE PRESENTATIONS

We present two cases of children with anticipated difficult airway management. The first child (14-year-old African American boy) had severe mucopolysaccharidosis with a history of failed anesthetic induction and failed airway management. The second child (3-year-old African American girl) had progressive lymphatic infiltration of the tongue, resulting in severe macroglossia. We describe a technique that forgoes inhalational induction, incorporates recent pediatric airway guidelines, and provides a greater margin of safety. The technique encompasses the use of drugs that facilitate sedation for intravenous access, without respiratory depression or airway obstruction, titrated use of medications to achieve anesthetic depth while preserving ventilatory drive and airway tone, and the continuous provision of directed oxygen flow during airway manipulation. Propofol and volatile gases were avoided to preserve airway tone and respiratory drive.

CONCLUSIONS

We emphasize that an intravenous induction technique utilizing medications that preserve airway tone and ventilatory drive, and the use of  continuous oxygen flow throughout airway manipulation, allows for successful management of children with a difficult airway. The common practice of volatile inhalational induction should be avoided in anticipated difficult pediatric airways.

Real-world outcomes of Selexipag for treatment of pulmonary hypertension in an Asian population

Funding Acknowledgements

Type of funding sources: None.

Introduction

Selexipag is an oral selective prostacyclin IP receptor agonist indicated for treatment of pulmonary arterial hypertension (PAH). Data on its real-world safety and efficacy in Asians is lacking.

Purpose

We sought to evaluate the clinical characteristics, treatment regimens and outcomes of patients initiated on selexipag in a tertiary cardiac centre in Asia.

Methods

This was a retrospective study on all patients initiated on selexipag from January 2017 to December 2020. Baseline and follow up characteristics including demographics, functional status and clinical data were collected. Clinical outcomes evaluated included hospitalisation for PH related complications and all-cause mortality. Patients were risk stratified using the COMPERA 2.0 risk scores.

Results

A total of 36 PAH patients were treated with selexipag. At baseline, most patients were WHO functional class II or III (36.4% and 51.5% respectively), with a NT-proBNP of 1335 pg/ml (557 – 2918) and 6 minute walk test (6MWT) duration of 327.5 ±126.4 meters. Selexipag was initiated at 200mcg twice daily dosage for all except one patient (started at 200mcg once daily) and the maximum tolerated dose ranged from 200mcg twice daily to 1400mcg twice daily, with majority tolerating up to a dose of 600mcg twice daily (58.3%). Side effects were reported in 23 patients (63.9%), of which headache (27.8%), diarrhea (30.6%) or musculoskeletal symptoms (27.8%) were predominant. After a median follow up duration of 25.9 ± 23.1 months, selexipag was stopped in 20 patients (55.6%), of which eight patients were due to PAH progression requiring alternative therapy, and 12 patients due to side effects from selexipag. At baseline, patients were classified into low (8.3%), intermediate-low (30.6%), intermediate-high (33.3%) and high risk (27.8%) respectively. Patients who continued on selexipag at follow up showed no change (46.2%), improvement (15.4%) and deterioration (38.5%) in risk score. In the overall cohort of 36 patients, majority (75%) had at least one hospitalisation for PAH related complications and 15 patients (41.7%) demised.

Conclusion

In this real-world study, while selexipag was associated with a stable or improved PAH risk scores in majority of patients, there was a subset of patients with disease progression or intolerance to the medication. Further studies are warranted to identify patients who will benefit most from this therapy.

Reconstructed meta-analysis of percutaneous coronary intervention versus coronary artery bypass grafting for left main disease

Background

Randomized controlled trials (RCTs) comparing percutaneous coronary intervention (PCI) with drug-eluting stents and coronary artery bypass grafting (CABG) for patients with left main coronary artery disease (LMCAD) have reported conflicting results.

Objectives

We performed a systematic review from inception to 23 May 2021 and one-stage reconstructed individual-patient data meta-analysis (IPDMA) that included 10-year mortality outcomes.

Methods

The primary outcome was 10-year all-cause mortality. Secondary outcomes included myocardial infarction (MI), stroke and unplanned revascularization at 5 years. We did IPDMA using published Kaplan-Meier curves to provide individual data points in coordinates and numbers at risk were used to increase the calibration accuracy of the reconstructed data. Shared frailty model or, when proportionality assumptions were not met, a restricted mean survival time model were fitted to compare outcomes between treatment groups.

Results

Of 583 articles retrieved, 5 RCTs were included. A total of 4595 patients from these 5 RCTs were randomly assigned to PCI (N=2297) or CABG (N=2298). The cumulative 10-year all-cause mortality after PCI and CABG was 12.0% versus 10.6% respectively (HR 1.093, 95% CI: 0.925–1.292; p=0.296). PCI conferred similar time-to-MI (RMST ratio 1.006, 95% CI: 0.992–1.021, p=0.391) and stroke (RMST ratio 1.005, 95% CI: 0.998–1.013, p=0.133) at 5 years. Unplanned revascularization was more frequent following PCI compared with CABG (HR 1.807, 95% CI: 1.524–2.144, p<0.001) at 5 years.

Conclusion

This meta-analysis using reconstructed participant-level time-to-event data showed no statistically significant difference in cumulative 10-year all-cause mortality between PCI versus CABG in the treatment of LMCAD.

Funding Acknowledgement

Type of funding sources: None.

Coronary artery bypass grafting versus percutaneous coronary intervention with stenting for multivessel coronary artery disease without left main coronary disease:reconstructed individual patient data

Background and aims

Data are emerging on 10-year mortality comparing coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) with stenting for multivessel disease (MVD) without left main (LM) involvement. We conducted an updated two-stage meta-analysis using reconstructed individual patient data to compare long-term mortality between CABG and PCI for patients with MVD without significant LM coronary disease.

Methods

Medline and Embase databases were searched for articles comparing CABG with PCI for MVD. A two-stage meta-analysis was conducted using reconstructed patient level survival data for all-cause mortality with subgroups by SYNTAX score. The shared-frailty and stratified Cox models were fitted to compare survival endpoints.

Results

We screened 1496 studies and included six randomized controlled trials with 7181 patients. PCI was associated with greater 10-year all-cause mortality risk (HR: 1.282, CI: 1.118–1.469, p<0.001) compared with CABG. In patients with low SYNTAX score, 10-year all-cause mortality after PCI was comparable to CABG (HR: 1.102, 0.822–1.479, p=0.516). However, in patients with moderate to high SYNTAX score, 10-year all-cause mortality was significantly higher after PCI compared with CABG (HR: 1.444, 1.122–1.858, p<0.001; HR: 1.856, 1.380–2.497, p<0.001 respectively).

Conclusion

This updated reconstructed individual patient-data meta-analysis revealed a sustained lower cumulative all-cause mortality of CABG over PCI for multivessel disease without LM involvement.

Funding Acknowledgement

Type of funding sources: None.

A 10-year cohort on prognostic outcomes in patients presenting with acute myocardial infarction complicated by cardiogenic shock and/or cardiac arrest

Background

Cardiogenic shock (CS) and cardiac arrest (CA) complicating acute myocardial infarction (AMI) portend unfavourable outcomes. This study examined the prognosis of patients presenting with AMI complicated by CS and/or CA.

Methods

Consecutive patients presented with AMI to a percutaneous coronary intervention-capable tertiary institution between 2011 and 2021 were studied. Patients were stratified based on the presence or absence of CS (CS+ or CS−) and CA (CA+ or CA−). The primary outcome was 30-day cardiovascular-related mortality. Subgroup analyses based on AMI-type and sex were conducted. Kaplan-Meier curves for cardiovascular-related mortality based on the AMI-type and sex were constructed.

Results

The study included 11,608 AMI patients, 283 of whom had CS+/CA+, 1,068 had CS+/CA−, 54 had CS−/CA+ and 10,203 had CS−/CA−. Cardiovascular-related mortality was significantly higher for CS+/CA+ (57.6%), followed by CS+/CA− (41.6%), CS−/CA+ (20.4%) and CS−/CA− (2.4%). Kaplan-Meier curves demonstrated CS+/CA+ group had the highest mortality (HR=36.26; 95% CI: 29.71–44.25, p<0.001), followed by CS+/CA− (HR=21.59; 95% CI: 18.47–25.24, p<0.001) and CS−/CA+ (HR=9.18; 95% CI: 5.02–16.80, p<0.001), with CS−/CA− as the reference. Those with NSTEMI had consistently higher cardiovascular-related mortality rates than their STEMI counterparts for all groups, apart from the CS+/CA+ group. The sex-specific analysis demonstrated that the survival curves for females with CS+/CA+, CS+/CA− and CS−/CA+ converged, whilst the survival curves for males diverged over time. The multivariable Cox regression revealed the presence of CS and CA are independent predictors of cardiovascular-related mortality, but not NSTEMI, when adjusted for age, gender, diabetes, left ventricular ejection fraction, chronic renal failure, and culprit vessel.

Conclusions

AMI associated with CA and CS portends the least favourable survival, followed by those with CS or CA alone. Excess mortality was observed in the traditionally perceived lower-risk groups, particularly in women. This calls for increased awareness amongst clinicians when managing this subset of high-risk patients.

Funding Acknowledgement

Type of funding sources: None.

Higher long-term mortality in patients with concomitant acute coronary syndrome and aortic stenosis

Background

Aortic stenosis (AS) and acute coronary syndrome (ACS) share similar cardiovascular risk factors, and their concomitant presentation is increasing in incidence with the aging population. Yet literature regarding the prognosis of patients with concomitant ACS and AS remains scarce.

Methods

This retrospective cohort study examined consecutive patients presenting with ACS (ST-segment elevation myocardial infarction [STEMI] and non-STEMI [NSTEMI]) and concomitant AS between 1 January 2011 and 31 March 2021 in a tertiary hospital. The cohort was divided into mild, moderate and severe AS based on index echocardiogram. The primary outcome was all-cause mortality. Kaplan-Meier curves were constructed to compare all-cause mortality among the three groups of patients, based on ACS type and left ventricular ejection fraction (LVEF). Multivariable Cox regression was performed to identify independent predictors of all-cause mortality.

Results

Of a total of 563 patients, 264 had mild (46.9%), 193 moderate (34.3%) and 106 severe AS (18.8%). The mean follow-up duration was 2.5 (± 2.4) years. Majority of patients (72.5%) presented with NSTEMI. Patients with moderate and severe AS had higher rates of all-cause mortality compared to those with mild AS (49.7% vs. 51.4% vs. 35.6% respectively, p=0.002). Concomitant moderate (HR 1.439, 95% CI 1.012–2.048, p=0.043) and severe AS (HR 1.844, 95% CI 1.159–2.933, p=0.010) were independent predictors of all-cause mortality after adjusting for age, gender, LVEF, ACS type, chronic kidney disease, diabetes, hypertension, coronary artery bypass grafting and aortic valve replacement as a time-dependent variable. The Kaplan-Meier curves demonstrated excess mortality in moderate and severe AS, compared to the mild AS group (p<0.001), with similar survival trends observed in the STEMI and the NSTEMI groups, as well as those with preserved LVEF.

Conclusion

Regardless of the ACS presentation type, long-term excess mortality in those with concomitant moderate or severe AS was observed. The adverse prognosis typically observed in patients with concomitant severe AS, in the setting of ACS, extends to patients with moderate AS.

Funding Acknowledgement

Type of funding sources: None.

AB0932 Patient and learner experience in a new set up of a rheum-derm combined care model for psoriatic arthritis

Background

Psoriasis (PsO) and musculoskeletal manifestations are common among patients with psoriatic arthritis (PsA). A shared-care model between rheumatologists and dermatologists has been advocated to promote early diagnosis and improve management care. Data from Asia is scanty. Patients’ and learners’ experience of shared-care models are seldom explored.

Objectives

We described the set-up of a new shared-cared PsA-PsO clinic incorporating service, education and research between rheumatologist and dermatologist for PsA. We describe the patients’ and learners’ experience of this shared-care model.

Methods

A combined care clinic was newly set up in 2019. Referrals were internal through either specialty. Each patient was first seen by a trainee, followed by both a dermatologist and rheumatologist simultaneously in the same consultation room. We collected patients’ and learners’ experience through self-administered survey.

Results

From May 2019 to January 2020, data from 44 visits (55% new referrals, 45% follow-up) from 28 patients were captured in the PsA-PsO clinic. 50% of cases were referred from either specialty. 34% were referred for diagnostic doubts, 66% were for therapeutic issues. 61% of patients continued follow-up in the PsA-PsO clinic, and 39% discharged back to respective care. From patients’ experience rated on scale from 0-10, median (interquartile range, IQR) rating of the care was 8 (7, 8). 69.2% and 96% of patients would recommend the care to others. Free text comments included enhanced convenience, time saving, and having both specialties input on management. From 20 learners (3 medial students, 12 residents, 4 senior residents and one scientist), 95% reported extremely or very beneficial to training, 77.8% reported improved confidence in care for PsA and/or PsO patients. The PsA-PsO clinic was temporally suspended during the Covid-19 viral pandemic since February 2020 due to lack of manpower and not fulfilling the spacing out requirement for infectious control. The service was resumed gradually from May 2021.

Conclusion

Despite challenges, we report the setup of a new care model between dermatologists and rheumatologists for care of patients with psoriatic disease. The care model was well received by patients. Learners from various levels reported benefit from the learning experience.

Disclosure of Interests

Cassandra Hong: None declared, Liwen Fang: None declared, Yi-Wei Yeo: None declared, Haur Yueh Lee: None declared, Andrea Low: None declared, Ying Ying Leung Speakers bureau: Received honorarium from Abbvie, DKSH, Janssen, Novartis and Pfizer.

POS1456 TEACHING NAILFOLD CAPILLAROSCOPY USING THE “FAST TRACK ALGORITHM” VIA AN ONLINE PLATFORM: THE ASIAN EXPERIENCE

Background

Nailfold capillaroscopy (NFC) is being increasingly used in the early identification of systemic sclerosis (SSc) related disorders. Recent studies have shown that an optimised simple capillaroscopic definition of normal and abnormal capillary morphology is reliable and a multi-centre consensus ‘fast track algorithm’ was developed by the European League against Rheumatism (EULAR) Study Group on Microcirculation in Rheumatic Diseases (SG MC/RD) to allow trainees to identify scleroderma patterns from non-scleroderma patterns.

Objectives

To validate the “fast track algorithm” taught via an online teaching platform to identify scleroderma patterns from non-scleroderma patterns on NFC.

Methods

Trainees participated in the NFC teaching workshops conducted via an online platform by the same SSc expert (AL) over 3 separate sessions. In the first part of the workshop (training), all trainees attended a talk on NFC by the SSc expert (AL) whereby they were taught the fast track algorithm to identify and classify NFC image patterns using a training set of images. The “fast track algorithm” (Figure 1) consists of three easy rules: 1) Rule number 1: the presence of ≥ 7 capillaries (capillary density) AND the absence of giant capillaries (capillary dimension) allows the rater to call the capillaroscopic image a “non-scleroderma pattern (category 1)”; 2) Rule number 2: the presence of giant capillaries or the presence of an extremely lowered capillary density (≤ 3 capillaries) in combination with abnormal shapes (= “late” scleroderma pattern) allows the rater to call the capillaroscopic image a “scleroderma pattern (category 2)”; 3) Rule number 3: if the image does not meet rule number 1 or rule number 2 then the image is automatically classified as a “non-scleroderma pattern (category 1)”. In the second part of the workshop (evaluation), each trainee independently rated 45 NFC images (30 seconds for each NFC image) in the same session, and submitted their answers in real time using an electronic form. The reading of the expert (AL) was considered the gold standard. AL is a SSc expert who had previously attended the EULAR workshop on NFC and has had more than 10 years of experience in NFC.

Figure 1.

Fast Track algorithm

Within 2-4 weeks of the initial rating exercise, trainees re-evaluated the same set of images for the intra-reader exercise under supervised conditions via the online platform.

We computed the inter- and intra-rater agreement using mean [standard deviation (SD)] Cohen’s Kappa, with the following values representing the degrees of agreement: <0 –poor; 0-0.20 –slight; 0.21-0.40 –fair; 0.41-0.60 –moderate; 0.61-0.80 –substantial; and 0.81-1.00 –almost perfect agreement.

Results

Ninety-eight trainees from Singapore, Malaysia, Indonesia, Hong Kong, Philippines, Taiwan, Myanmar and Brunei included rheumatologists, rheumatology trainees, pediatric rheumatologists, internists and nurses. Fifty-four participants were novices with no prior NFC experience, 38 participants were “moderately experienced” (< 5 years of NFC experience) and 1 participant was “experienced” with more than 5 years of NFC experience.

The mean (SD) inter-rater kappa of the 98 trainees was 0.71 (0.13). For the 61 trainees who participated in the re-evaluation session, mean (SD) inter-rater and intra-rater kappa were 0.74 (0.16) and 0.71 (0.15), respectively.

Conclusion

There was substantial inter- and intra-rater agreement. This is the first study in Asia examining NFC training using the EULAR SG MC/RD fast track algorithm and our results support the importance of standardized teaching for NFC.

References

Nil

From: Smith V, Vanhaecke A, Herrick AL, et al. EULAR Study Group on Microcirculation in Rheumatic Diseases. Fast track algorithm: How to differentiate a “scleroderma pattern” from a “non-scleroderm pattern”. Autoimmun Rev. 2019 Nov;18(11):102394.

Disclosure of Interests

None declared

POS0200 POST-mRNA VACCINE FLARES IN AUTOIMMUNE INFLAMMATORY RHEUMATIC DISEASES: INTERIM RESULTS FROM THE CORONAVIRUS NATIONAL VACCINE REGISTRY FOR IMMUNE DISEASES SINGAPORE (CONVIN-SING)

Background

Published data suggest no increased rate of flare of autoimmune inflammatory rheumatic diseases (AIIRD) after COVID-19 mRNA vaccination; however, the studies are limited by small sample size, short follow up or at risk of selection bias (voluntary physician reports or patient surveys).

Objectives

To study flares of AIIRD within three months of the first dose of an anti-SARS-COV2 mRNA vaccine.

Methods

A retrospective cohort study of consecutive AIIRD patients ≥ 12 years old, across six public hospitals in Singapore who received at least one dose of an mRNA (Pfizer/BioNTech or Moderna) vaccine. Data were censored at the first post-vaccine clinic visit when the patient had flared or if ≥ three months had elapsed since the first dose of the vaccine, whichever came first. Predictors of flare were determined by Cox proportional hazards analysis and time to flare was examined using a Nelson Aalen cumulative hazard estimate (Figure 1).

Figure 1.

Nelson-Aalen curve of flares over time

Results

2339 patients (74% Chinese, 72% female) of median (IQR) age 64 (53, 71) years were included in the interim analysis (Table 1). 2112 (90%) had the Pfizer/BioNTech vaccine and 195 (8%) had Moderna, with a median (IQR) interval of 21 (21, 23) days between the two doses. The most common AIIRD diagnoses were Rheumatoid arthritis (1063, 45%), Psoriatic arthritis (296, 12.6%) and Systemic lupus erythematosus (SLE) (288, 12.3%). 186 (8%) were treated with biologics/ targeted disease modifying agents. 2125 (91%) patients were in low disease activity or remission. Treatment was interrupted for vaccination in only 18 (0.8%) patients. Seven (0.3%) patients had previous COVID-19 infection.

Table 1.

Patient characteristics

Baseline characteristicsNo flares(n = 1887, %)Flares within 0—3 months of 1st vaccine dose (n= 272, %)Flares outside of 0 – 3 months after 1st vaccine dose (n = 180, %)Age (median years, IQR)64 (53, 71)61 (50, 69)65 (55, 71)RaceChinese1386 (73)206 (76)129 (72)Malay193 (10)28 (10)20 (11)Indian195 (10)27 (10)26 (14)GenderFemale1367 (72)200 (74)117 (65)Vaccine typePfizer/BioNTech1713 (92)239 (90)160 (90)Moderna149 (8)28 (10)18 (10)DiagnosisRheumatoid Arthritis831 (44)139 (51)93 (52)Systemic Lupus Erythematosus269 (14)20 (7)9 (5)Psoriatic Arthritis225 (12)42 (15)29 (16)Spondyloarthropathies141 (7)21 (7)17 (9)Sjogren’s Syndrome114 (6)15 (6)8 (4)Systemic sclerosis94 (5)4 (1)6 (3)Baseline Physician Disease ActivityRemission1007 (53)99 (36)63 (35)Low Disease Activity731 (39)128 (47)97 (54)Moderate Disease Activity134 (7)40 (15)20 (11)High Disease Activity15 (1)5 (2)0

452 (19%) flares were recorded during 9798.8 patient-months [4.6/100 patient-months, median (IQR) follow up duration 4.2 (3.3, 5.3) months], of which 272 (11.6%) patients flared within the 3-month period of interest and 180 (7.7%) flared outside of the 3-month period (Table 1). Median (IQR) time-to-flare was 40.5 (18, 56.6) days. 60 (22.1%) were mild and self-limiting, 170 (62.5%) were mild-moderate and 42 (15.4%) were severe. 190 (69.8%) of those who flared required escalation of treatment and 15 (5.5%) required hospital admission. 239 (10.2%) had improved disease activity after the vaccine.

On multivariate Cox regression analysis, patients in the oldest age tertile [median (IQR) 74 (71, 79) years] were less likely to flare [HR 0.80 (95% CI 0.63, 1.00), p = 0.05] Patients with inflammatory arthritis (compared with connective tissue disease, vasculitis and others) and patients with baseline active disease were more likely to flare [HR 1.72 (95% CI 1.35, 2.20), p < 0.001 and 1.82 (95% CI 1.39, 2.39), p < 0.001 respectively]

Conclusion

There was a moderately high rate of AIIRD flares after mRNA vaccination; however, there was no clustering of flares in the immediate post-vaccine period to suggest causality. Older patients were less likely to flare, while those with inflammatory arthritis and active disease at baseline were more likely to flare.

Disclosure of Interests

Margaret Ma Grant/research support from: Support grant from multiple companies for the Singapore Biologics registry, Amelia Santosa Speakers bureau: Amgen Talk, Consultant of: Pfizer ad board, Kok Ooi Kong: None declared, Chuanhui Xu: None declared, Johnston Tang Gin Xiang: None declared, Gim Gee Teng Speakers bureau: Boehringer Ingleheim, Anselm Mak Speakers bureau: J&J and GSK, Grant/research support from: GSK - the supported studies programme, Sen Hee Tay: None declared, Victoria Wei Wen Ng: None declared, Joshua Zhi En Koh: None declared, Warren Fong Speakers bureau: speaker for Abbvie, DKSH, GSK, Novartis, Li-Ching Chew Speakers bureau: pfizer and Abbvie, Consultant of: Pfizer and Abbvie Advisory Board meeting, Grant/research support from: Abbvie educational grant for ultrasound conference, Andrea Low Speakers bureau: Boehringer Ingeilheim, Consultant of: Consultant/steering group committee for BI and J&J, annie law: None declared, Yih Jia Poh: None declared, Siaw Ing Yeo Grant/research support from: Multiple pharmaceutical companies for the support of the National Biologics Registry, Ying Ying Leung Speakers bureau: Abbvie, DKSH, Jassen, Novartis and Pfizer, Wei-Rui Goh: None declared, Chuah Tyng Yu: None declared, Nur Emillia Roslan: None declared, Stanley Angkodjojo Speakers bureau: Boehringer Ingeilheim, Consultant of: Abbvie and DKSH, Kee Fong Phang: None declared, Thaschawee Arkachaisri: None declared, Melonie Sriranganathan: None declared, Teck Choon TAN: None declared, Peter Cheung Consultant of: Ad board for Boehringer Ingleheim, novartis, janssen and abbvie, Grant/research support from: Novartis, Manjari Lahiri Speakers bureau: J&J, DSKH, Consultant of: DSKH, Gilead, Grant/research support from: Multiple pharma companies contributed to the Singapore Biologics registry

Novartis

POS1411 EARLY IDENTIFICATION OF AXIAL SPONDYLOARTHRITIS IN A MULTI-ETHNIC ASIAN POPULATION

Background:

To facilitate earlier diagnosis of spondyloarthritis (SpA), we have previously cross-culturally adapted a self-administered screening questionnaire.

Objectives:

We aimed to improve the sensitivity of this questionnaire as a screening tool by comparing various scoring methods.

Methods:

Subjects newly referred to a rheumatology clinic self-administered the questionnaire before seeing a rheumatologist. Identification of axial SpA by the questionnaire using original scoring (Method A) and scoring based on Assessment of SpondyloArthritis International Society (ASAS) inflammatory back pain (IBP) criteria (Method B), ASAS referral criteria (Method C), ASAS classification criteria (Method D) and a combination of ASAS referral and classification criteria (Method E) were compared to classification by the ASAS classification criteria and diagnosis by rheumatologist. Since Methods B-E were based on SpA features, we compared self-reported vs rheumatologist-documented features in subjects with axial SpA.

Results:

Of 1418 subjects (age: 54 ± 14 years, female: 73%), 39 were classified as axial SpA cases by classification criteria. Methods A-E yielded sensitivities of 39%, 72%, 67%, 49% and 85%, respectively, among patients newly referred to the rheumatology clinic (Table 1). Rheumatologist-documented clinical SpA features exceeded self-report for IBP (62 vs 44%) and uveitis (15 vs 5%). The reverse was true for arthritis (21 vs 80%), enthesitis (28 vs 33%), dactylitis (3 vs 18%), good response to NSAIDs (33 vs 41%) and family history for SpA (5 vs 10%).

Table 1.

Performance of the five scoring methods for the cross-culturally adapted Hamilton axial SpA questionnaire.

Scoring methodSensitivity(95% confidence interval)Specificity(95% confidence interval)Positive predictive value(95% confidence interval)Negative predictive value(95% confidence interval)Method A38.5(23.4 – 55.4)93.7(92.3 – 94.9)14.7(8.5 – 23.1)98.2(97.3 – 98.8)Method B71.8(55.1 – 85.0)73.1(70.7 – 75.4)7.0(4.7 – 10.0)98.9(98.1 – 99.5)Method C66.7(49.8 – 80.9)77.8(75.5 – 80.0)7.8(5.2 – 11.3)98.8(98.0 – 99.4)Method D48.7(32.4 – 65.2)74.9(72.5 – 77.2)5.2(3.2 – 8.0)98.1(97.1 – 98.8)Method E84.6(69.5 – 94.1)37.2(34.6 – 39.8)3.7(2.5 – 5.1)98.8(97.5 – 99.6)

Method A: the original scoring defined by the questionnaire developers; Method B: a scoring based on the ASAS IBP criteria; Method C: a scoring based on the ASAS referral criteria; Method D: a scoring based on the ASAS classification criteria for axial and peripheral SpA; Method E: a scoring based on a combination of the ASAS referral and classification criteria.

Conclusion:

A self-administered questionnaire scored based on a combination of ASAS referral and classification criteria achieved high sensitivity in identifying axial SpA in subjects referred to a rheumatology clinic. This supports its evaluation as a screening tool for axial SpA in the general population.

References:

[1]Xiang L, Teo EPS, Low AHL, Leung YY, Fong W, Xin X, et al. Cross-cultural adaptation of the Hamilton axial spondyloarthritis questionnaire and development of a Chinese version in a multi-ethnic Asian population. Int J Rheum Dis. 2019;22(9):1652-60.

[2]Sieper J, Rudwaleit M, Baraliakos X, Brandt J, Braun J, Burgos-Vargas R, et al. The Assessment of SpondyloArthritis international Society (ASAS) handbook: a guide to assess spondyloarthritis. Annals of the rheumatic diseases. 2009;68 Suppl 2:ii1-44.

[3]Poddubnyy D, van Tubergen A, Landewe R, Sieper J, van der Heijde D. Development of an ASAS-endorsed recommendation for the early referral of patients with a suspicion of axial spondyloarthritis. Annals of the rheumatic diseases. 2015;74(8):1483-7.

[4]Rudwaleit M, van der Heijde D, Landewe R, Akkoc N, Brandt J, Chou CT, et al. The Assessment of SpondyloArthritis International Society classification criteria for peripheral spondyloarthritis and for spondyloarthritis in general. Annals of the rheumatic diseases. 2011;70(1):25-31.

Acknowledgements:

This work was supported by a Health Services Research Grant (HSRG) from the Singapore Ministry of Health National Medical Research Council [grant number: NMRC/HSRG/0075/2017].

Disclosure of Interests:

None declared

POS1413 INTERVAL BETWEEN SYMPTOM ONSET AND DIAGNOSIS AMONG PATIENTS WITH AUTOIMMUNE RHEUMATIC DISEASES IN A MULTI-ETHNIC ASIAN POPULATION

Background:

The interval between symptom onset and diagnosis can often be longer than is ideal in autoimmune rheumatic diseases (ARDs).

Objectives:

We aimed to characterise this interval among patients newly diagnosed with ARDs in a multi-ethnic Asian population and to identify factors associated with a longer interval.

Methods:

We used Scott’s model of pathways to treatment to characterise the interval between symptom onset and diagnosis into 4 intervals: #1 between symptom onset and first seeking medical attention, #2 between first medical attention and rheumatology referral, #3 between rheumatology referral and first rheumatology assessment, and #4 between first rheumatology assessment and diagnosis. Linear regression models were used to identify factors associated with a longer the overall interval between symptom onset and diagnosis and Interval #1.

Results:

Among 259 patients (age: 51±15 years, female: 71%, most common three ARDs: rheumatoid arthritis (n = 75), axial spondyloarthritis (n = 40) and psoriatic arthritis (n = 35)), the median overall interval was 11.5 months. Interval #1 (median = 4.9 months) was significantly longer than the other intervals (Table 1). Patients with axial spondyloarthritis had a significantly longer overall interval (median = 38.7 months) and Interval #1 (median = 26.6 months) compared to patients with RA (median = 7.6 and 3.5 months, respectively), PsA (median = 7.0 and 2.6 months, respectively) and the other ARDs. Gender was the only patient-related factor significantly associated with the overall interval (reference = male, coefficient = -15.3, p = 0.033) in regression models.

Conclusion:

A longer than ideal interval between symptom onset and diagnosis was observed among patients with ARDs. This was primarily due to a relatively long interval between symptom onset and first seeking medical attention, and highlights the importance of interventions targeting patients prior to first medical attention in reducing the duration between symptom onset and diagnosis.

References:

[1]Scott SE, Walter FM, Webster A, Sutton S, Emery J. The model of pathways to treatment: conceptualization and integration with existing theory. Br J Health Psychol. 2013;18(1):45-65.

Table 1.

Interval between symptom onset and diagnosis

Overall interval, months, median (lower and upper quartiles)†Interval #1, months, median (lower and upper quartiles)Interval #2, months, median (lower and upper quartiles)Interval #3, months, median (lower and upper quartiles)Interval #4, months, median (lower and upper quartiles)Overall(n = 259)11.5(4.7 – 36.0)4.9(1.0 – 24.0)0.3(0.0 – 3.9)1.5(0.8 – 1.8)0.0(0.0 – 1.2)RA(n = 75)7.6(3.1 – 14.8)3.5(1.3 – 11.6)0.2(0.0 – 2.5)1.3(0.6 – 1.6)0.0(0.0 – 0.2)AxSpA(n = 40)38.7(9.6 – 66.7)26.6(4.2 – 56.1)1.6(0.0 – 7.6)1.6(1.2 – 2.3)0.0(0.0 – 2.0)PsA(n = 35)7.0(3.0 – 28.4)2.6(0.2 – 11.3)0.5(0.2 – 3.9)1.6(0.6 – 1.7)0.0(0.0 – 0.0)Seronegative IA(n = 21)12.0(4.7 – 22.8)6.4(1.9 – 34.4)0.1(0.0 – 4.6)1.4(1.3 – 1.5)0.0(0.0 – 0.8)SjS(n = 27)14.2(6.0 – 48.0)4.6(0.6 – 19.0)0.3(0.0 – 3.9)1.6(0.9 – 1.9)0.8(0.0 – 2.3)UCTD(n = 27)15.7(5.1 – 39.8)2.2(0.7 – 24.0)0.8(0.1 – 8.1)1.6(0.5 – 1.8)1.2(0.0 – 2.1)Other ARDs(n = 34)8.1(5.3 – 36.0)6.3(0.9 – 31.7)0.2(0.0 – 1.1)1.5(1.2 – 1.8)0.3(0.0 – 1.1)

Overall interval and Intervals #1-4: refer to abstract for definitions; RA: rheumatoid arthritis; axSpA: axial spondyloarthritis; PsA: psoriatic arthritis; IA: inflammatory arthritis; SjS: Sjögren’s syndrome; UCTD: undifferentiated connective tissue disease; other ARDs: systemic lupus erythematosus, systemic sclerosis, idiopathic inflammatory myopathies, palindromic rheumatism and overlap syndromes.

†Intervals #1-4 did not sum to the overall interval mainly due to the fact that Intervals #1-4 might not available for all patients.

Disclosure of Interests:

None declared

POS0417 EXOGENOUS CXCL5 RESTORES ENDOGENOUS BLOOD-TISSUE CHEMOKINE GRADIENT TO IMPROVE SURVIVAL IN MURINE LUPUS

Background:

Systemic lupus erythematosus (SLE) is a multi-organ autoimmune disease that is potentially fatal. There is an unmet need to improve current therapies. In patients with SLE, we observed that serum CXCL5 levels were significantly lower than healthy control subjects and negatively correlated with disease activity(1-9).

Objectives:

The aim of this study is to elucidate the effect of supplemental serum CXCL5 in abrogating the pathological processes of SLE.

Methods:

Ten doses of exogenous CXCL5 (3µg/kg) was administered to 16-week-old Faslpr mice weekly by intravenous injection. Mice were monitored for 10 weeks. Splenic immune profile was measured by flow cytometry. Circulating cytokine and immunoglobulin profile were detected by Luminex technology. Renal function was evaluated by urinary spot albumin creatinine ratio. In situ renal immune cell infiltration and complement 3 deposition were detected by Haematoxylin and Eosin (H&E) and immunohistochemistry staining. The molecular pathways involved were examined by RNA sequencing.

Results:

In Faslpr mice, intravenous administration of exogenous CXCL5 significantly improved mouse survival with concomitant reduction of autoantibody secretion, proteinuria, complement 3 deposition, neutrophil infiltration and lupus nephritis classes. Through evaluating the changes of immune profile, cytokine profile and molecular pathways, we found that intravenous CXCL5 reduced inflammation via an orchestral effect of regulating neutrophil trafficking and modulating helper T cell-mediated immune response. Pharmacokinetic and real-time Polymerase Chain Reaction studies further demonstrated that this orchestration was triggered by a cascade reaction - restoring vascular under-expressed CXCL5 by an exogenous stimulation, re-establishing the normal serum levels of endogenous CXCL5 and reverting the CXCL5 chemokine gradient between inflamed tissues and blood circulation.

Conclusion:

Managing the dysregulation of CXCL5 by exogenous supplement may provide a new option for SLE therapy.

References:

[1]Dufies M, Grytsai O, Ronco C, et al. New CXCR1/CXCR2 inhibitors represent an effective treatment for kidney or head and neck cancers sensitive or refractory to reference treatments. Theranostics. 2019;9(18):5332-5346. doi:10.7150/thno.34681

[2]Yildirim K, Colak E, Aktimur R, et al. Clinical Value of CXCL5 for Determining of Colorectal Cancer. Asian Pac J Cancer Prev. Sep 26 2018;19(9):2481-2484. doi:10.22034/apjcp.2018.19.9.2481

[3]Wu K, Yu S, Liu Q, Bai X, Zheng X. The clinical significance of CXCL5 in non-small cell lung cancer. Onco Targets Ther. 2017;10:5561-5573. doi:10.2147/ott.s148772

[4]Zhao J, Ou B, Han D, et al. Tumor-derived CXCL5 promotes human colorectal cancer metastasis through activation of the ERK/Elk-1/Snail and AKT/GSK3beta/beta-catenin pathways. Mol Cancer. Mar 29 2017;16(1):70. doi:10.1186/s12943-017-0629-4

[5]Han KQ, Han H, He XQ, et al. Chemokine CXCL1 may serve as a potential molecular target for hepatocellular carcinoma. Cancer Med. Oct 2016;5(10):2861-2871. doi:10.1002/cam4.843

[6]Pappa CA, Tsirakis G, Kanellou P, et al. Monitoring serum levels ELR+ CXC chemokines and the relationship between microvessel density and angiogenic growth factors in multiple myeloma. Cytokine. Dec 2011;56(3):616-20. doi:10.1016/j.cyto.2011.08.034

[7]Zhang L, Li H, Ge C, et al. CXCL3 contributes to CD133(+) CSCs maintenance and forms a positive feedback regulation loop with CD133 in HCC via Erk1/2 phosphorylation. Sci Rep. Jun 3 2016;6:27426. doi:10.1038/srep27426

[8]Matsubara J, Honda K, Ono M, et al. Reduced plasma level of CXC chemokine ligand 7 in patients with pancreatic cancer. Cancer Epidemiol Biomarkers Prev. Jan 2011;20(1):160-71. doi:10.1158/1055- 9965.epi-10-0397

[9]Ma Y, Ren Y, Dai ZJ, Wu CJ, Ji YH, Xu J. IL-6, IL-8 and TNF-alpha levels correlate with disease stage in breast cancer patients. Adv Clin Exp Med. May-Jun 2017;26(3):421-426. doi:10.17219/acem/62120

Disclosure of Interests:

None declared

AB0128 CXCL5 DAMPENS INFLAMMATION IN THE PRE-CLINICAL MODEL OF SYSTEMIC LUPUS ERYTHEMATOSUS VIA THE ORCHESTRAL EFFECT OF REGULATING NEUTROPHIL TRAFFICKING AND SUPPRESSING HELPER T CELL-MEDIATED IMMUNE RESPONSE

Background:

Patients with systemic lupus erythematosus (SLE) suffer from severe morbidity and mortality1-4, either from the disease itself or from side effects of immunosuppression5. Discovery of novel effective therapies with less toxicity is an urgent need.

Objectives:

The aim of this study is to elucidate the therapeutic potential and working mechanism of cytokine CXCL5 in lupus mice.

Methods:

Treatment with CXCL5, bone marrow (BM)-MSCs, standard of care (SOC) with combination of methylprednisolone and cyclophosphamide was given to 16-week-old Faslprmice. Mice were monitored for 10 weeks. Splenic immune cell subsets were measured by flow cytometry. Circulating cytokine and immunoglobulin were detected by Luminex technology. Renal function was evaluated by urinary spot albumin creatinine ratio. In situ renal immune cell infiltration and complement 3 deposition were detected by Haematoxylin and Eosin (H&E) staining and immunohistochemistry.

Results:

CXCL5 demonstrated consistent and potent immunosuppressive capacity in suppressing SLE with reduced autoantibody secretion, lymphoproliferation and preserved kidney function. With further exploration, we proved that CXCL5 reduced the proliferation of helper T cells (TH1 and TH2) in thein vitrofunctional assay. When we administrated CXCL5 to lupus mice, it promoted the proliferation of regulatory T cells and reduced the proliferation of TH17 cells, macrophages and neutrophils. Multiple proinflammatory cytokines including IL-2, IL-6, IL-12, IL-17A, KC/CXCL1, MIP-1β/CCL4 and TNF-α were also reduced. When combined with SOC, CXCL5 boosted its therapeutic effect and reduced the relevant indices of disease activity. When we correlated the effect of four different treatment groups (CXCL5, BM-MSCs, SOC, and CXCL5 plus SOC) on mice survival and target cell changes, we found that TH17 cells were the key effector cells involved in the pathogenesis of SLE.

Conclusion:

These findings demonstrated that CXCL5 dampens inflammation in the pre-clinical model of systemic lupus erythematosus via the orchestral effect of regulating neutrophil trafficking and suppressing helper T cell-mediated immune response. Administrating exogenous CXCL5 might be an attractive option to treat patients with lupus.

References:

[1]Ji S, Guo Q, Han Y, Tan G, Luo Y, Zeng F. Mesenchymal stem cell transplantation inhibits abnormal activation of Akt/GSK3beta signaling pathway in T cells from systemic lupus erythematosus mice.Cell Physiol Biochem.2012;29(5-6):705-712.

[2]Peng SL. Altered T and B lymphocyte signaling pathways in lupus.Autoimmun Rev.2009;8(3):179-183.

[3]Ferucci ED, Johnston JM, Gaddy JR, et al. Prevalence and incidence of systemic lupus erythematosus in a population-based registry of American Indian and Alaska Native people, 2007-2009.Arthritis Rheumatol.2014;66(9):2494-2502.

[4]Jakes RW, Bae SC, Louthrenoo W, Mok CC, Navarra SV, Kwon N. Systematic review of the epidemiology of systemic lupus erythematosus in the Asia-Pacific region: prevalence, incidence, clinical features, and mortality.Arthritis Care Res (Hoboken).2012;64(2):159-168.

[5]Sattwika PD, Mustafa R, Paramaiswari A, Herningtyas EH. Stem cells for lupus nephritis: a concise review of current knowledge.Lupus.2018;27(12):1881-1897.

Acknowledgments:

The work was supported by SMART II Centre Grant (NMRC/CG/M011/2017_SGH) and SingHealth Foundation (SHF/FG638P/2016).

Disclosure of Interests:

None declared

Comparison of platinum chromium everolimus-eluting stent with cobalt chromium everolimus-eluting stent in unselected patients undergoing percutaneous coronary intervention

OBJECTIVE

The recent PLATINUM trial has demonstrated that the use of the new generation platinum chromium everolimus-eluting stents (PtCr-EES) yield clinical outcomes similar to those obtained by the use of cobalt chromium everolimus-eluting stents (CoCr-EES) in selected patients with 1 or 2 de novo coronary artery lesions. This study aimed to compare the safety and efficacy of the PtCr-EES and CoCr-EES in unselected patients from a real-life single-center registry.

PATIENTS AND METHODS

  From July 2009 through November 2010, 788 consecutive patients in our institution with symptomatic coronary artery disease who were treated with the CoCr-EES (n = 410) or PtCr-EES (n = 378) were enrolled into this study. The primary endpoint of the study was target-lesion failure (TLF) at 12-month follow-up and the secondary endpoints were major adverse cardiovascular events and stent thrombosis.

RESULTS

The prevalence of TLF in the PtCr-EES group (4.5%) was similar to that in the CoCr-EES group (3.9%). In addition, there were no significant differences in the 12-month rates of cardiac death (2.1% vs. 1.5%), myocardial infarction (2.4% vs. 3.9%), ischemia-driven target lesion revascularization (2.4% vs. 2.2%), and definite or probable stent thrombosis (0.5% vs. 1.5%, all p > 0.05).

CONCLUSIONS

At 12-month follow-up, the PtCr-EES is comparable in safety and efficacy to the CoCr-EES in unselected patients with coronary artery diseases.

A ring calcified benign thymoma in a patient with asbestos exposure

The differential diagnosis of a mediastinal mass with ring calcification on chest X-ray includes thymoma,dermoid tumour, teratoma, neurogenic tumours and lymphadenopathy. Cross-sectional imaging via CT can aid diagnosis. This case may also demonstrate an association between asbestos exposure and thymoma calcification.

Knowledge and behaviour regarding heart disease prevention in Chinese Canadian immigrants

OBJECTIVE

Although Chinese are one of the fastest growing minorities in Canada, there is little information about heart disease prevention behaviour in Chinese immigrants. Our objective was to examine the knowledge and practices of Chinese immigrants regarding heart disease prevention.

METHODS

504 randomly selected Chinese adult immigrants participated in a community-based, in-person survey in Vancouver during 2005. The survey included questions on heart disease prevention knowledge and practices.

RESULTS

Although respondents were quite knowledgeable about heart disease risk factors, their behaviours to reduce heart disease risk were generally low. Thirteen percent of respondents consumed five or more servings of fruit/vegetables per day; 37% engaged in regular physical activity; 54% never used tobacco; 81% had received a blood pressure check in the past 2 years; and 54% had received a cholesterol test in the past 5 years. Differences were found in these behaviours by gender, age, English fluency, birth country and duration of residence in North America. The associations are presented between these demographic variables and heart disease prevention behaviours.

CONCLUSION

Heart disease prevention programs are needed in Chinese immigrant populations, especially aimed at increasing fruit/vegetable consumption and regular physical activity. Efforts are also needed to decrease tobacco use and to increase cholesterol testing.

Knowledge and behaviour regarding heart disease prevention in Chinese Canadian immigrants

OBJECTIVE

Although Chinese are one of the fastest growing minorities in Canada, there is little information about heart disease prevention behaviour in Chinese immigrants. Our objective was to examine the knowledge and practices of Chinese immigrants regarding heart disease prevention.

METHODS

504 randomly selected Chinese adult immigrants participated in a community-based, in-person survey in Vancouver during 2005. The survey included questions on heart disease prevention knowledge and practices.

RESULTS

Although respondents were quite knowledgeable about heart disease risk factors, their behaviours to reduce heart disease risk were generally low. Thirteen percent of respondents consumed five or more servings of fruit/vegetables per day; 37% engaged in regular physical activity; 54% never used tobacco; 81% had received a blood pressure check in the past 2 years; and 54% had received a cholesterol test in the past 5 years. Differences were found in these behaviours by gender, age, English fluency, birth country and duration of residence in North America. The associations are presented between these demographic variables and heart disease prevention behaviours.

CONCLUSION

Heart disease prevention programs are needed in Chinese immigrant populations, especially aimed at increasing fruit/vegetable consumption and regular physical activity. Efforts are also needed to decrease tobacco use and to increase cholesterol testing.

The effect of social deprivation on local authority sickness absence rates

BACKGROUND

There is an extensive body of research relating to the association between ergonomic and psychosocial factors on sickness absence rates. The impact of deprivation on health indices has also been extensively investigated. However, published research has not investigated the extent of any association between standard measures of deprivation and sickness absence and ill-health retirement rates.

AIM

To establish if a relationship exists between standard measures of deprivation, used by the UK central government to determine regional health and social welfare funding, and sickness absence and ill-health early retirement rates in English local government employers.

METHODS

Local authority sickness absence rates for 2001-02 were regressed against the 2004 Indices of Multiple Deprivation in a multiple regression model that also included size and type of organization as independent variables. A second model using ill-health retirement as the dependent variable was also estimated.

RESULTS

In the full regression models, organization size was not significant and reduced models with deprivation and organization type (depending on whether teachers were employed by the organization or not) were estimated. For the sickness absence model, the adjusted R(2) was 0.20, with 17% of the variation in sickness absence rates being explained by deprivation rank. Ill-health retirement showed a similar relationship with deprivation. In both models, the deprivation coefficients were highly significant: for sickness absence [t = -7.85 (P = 0.00)] and for ill-health retirement [t = -4.79 (P = 0.00)].

CONCLUSIONS

A significant proportion of variation in sickness absence and ill-health retirement rates in local government in England are associated with local measures of deprivation. Recognition of the impact of deprivation on sickness absence has implications for a number of different areas of work. These include target setting for Local Government Best Value Performance Indicators, history taking in sickness absence consultations and the role of deprivation as a confounding factor in sickness absence intervention studies.

Hepatitis B knowledge, testing and vaccination levels in Chinese immigrants to British Columbia, Canada

BACKGROUND

Little is known about hepatitis B (HBV) and liver cancer control in Chinese in Canada. Liver cancer, a significant health problem in Asia, is preventable and can be controlled through HBV blood testing, vaccination, and community education about HBV.

OBJECTIVE

The overall goal was to increase HBV testing and vaccination in Chinese adult Canadians. The objective was to present findings on HBV testing, vaccination and knowledge in Chinese immigrants.

METHODS

504 randomly selected Chinese adult immigrants residing in Vancouver responded to the survey which examined HBV blood testing and vaccination practices, HBV knowledge levels and socio-demographic characteristics. Face-to-face interviews were conducted in Cantonese, Mandarin, or English.

RESULTS

57% of participants reported that they had received HBV blood testing, 38% had been vaccinated, and 6% were known HBV carriers. There were gender differences, with lower rates of testing and vaccination, and higher chronic carrier rates, among men. Over 80% knew that HBV can be spread by asymptomatic persons and can cause cirrhosis and liver cancer. However, confusion existed about the routes of HBV transmission.

INTERPRETATION

A sizeable proportion of Chinese adult immigrants in Vancouver have not been tested or vaccinated for HBV. Knowledge level, especially about routes of HBV transmission, was low. This is a concern, given that chronic HBV infection is the most common cause of liver cancer in Asian North Americans. To improve knowledge, reduce risk of infection and the burden of chronic infection and its sequelae in immigrant populations, continuing educational efforts are needed.

Hepatitis B knowledge, testing and vaccination levels in Chinese immigrants to British Columbia, Canada

BACKGROUND

Little is known about hepatitis B (HBV) and liver cancer control in Chinese in Canada. Liver cancer, a significant health problem in Asia, is preventable and can be controlled through HBV blood testing, vaccination, and community education about HBV.

OBJECTIVE

The overall goal was to increase HBV testing and vaccination in Chinese adult Canadians. The objective was to present findings on HBV testing, vaccination and knowledge in Chinese immigrants.

METHODS

504 randomly selected Chinese adult immigrants residing in Vancouver responded to the survey which examined HBV blood testing and vaccination practices, HBV knowledge levels and socio-demographic characteristics. Face-to-face interviews were conducted in Cantonese, Mandarin, or English.

RESULTS

57% of participants reported that they had received HBV blood testing, 38% had been vaccinated, and 6% were known HBV carriers. There were gender differences, with lower rates of testing and vaccination, and higher chronic carrier rates, among men. Over 80% knew that HBV can be spread by asymptomatic persons and can cause cirrhosis and liver cancer. However, confusion existed about the routes of HBV transmission.

INTERPRETATION

A sizeable proportion of Chinese adult immigrants in Vancouver have not been tested or vaccinated for HBV. Knowledge level, especially about routes of HBV transmission, was low. This is a concern, given that chronic HBV infection is the most common cause of liver cancer in Asian North Americans. To improve knowledge, reduce risk of infection and the burden of chronic infection and its sequelae in immigrant populations, continuing educational efforts are needed.

Predisposing, reinforcing and enabling factors associated with hepatitis B testing in Chinese Canadians in British Columbia

BACKGROUND

Liver cancer, a significant health problem in Chinese, can be controlled through HBV blood testing, vaccination, and community education about HBV. The PRECEDE framework has been very helpful in identifying factors associated with health practices.

OBJECTIVES

The objective was to identify factors associated with HBV testing in Chinese Canadians, using the PRECEDE framework.

METHODS

Five hundred and thirty-three randomly selected Chinese Canadian adults were interviewed about HBV blood testing practices. Factors were grouped as predisposing, reinforcing and enabling.

RESULTS

Fifty-five percent had received HBV blood testing. Several predisposing factors, all reinforcing factors and one enabling factor were associated with HBV testing in bivariate analysis. A physician's recommendation for testing was the strongest factor associated with testing in multiple logistic regression analysis (OR=4.4, p<0.0001).

INTERPRETATION

Many Chinese Canadian adults in Vancouver have not been tested for HBV. Continuing educational efforts are needed and the PRECEDE framework can inform the development of health education interventions.

Acoustic Analysis of the Voice in Pediatric Cochlear Implant Recipients: A Longitudinal Study

OBJECTIVE

To characterize inherent acoustic abnormalities of the deaf pediatric voice and the effect of artificially restoring auditory feedback with cochlear implantation.

DESIGN

Inception cohort.

SETTING

Academic referral center.

PATIENTS

Twenty-one children with severe to profound hearing loss (15 prelingually deaf, 6 postlingually deaf) accepted into the cochlear implant program were followed for up to 6 months. Patients unable to perform the vocal exercises were excluded.

INTERVENTIONS

Objective voice analysis was performed using the Computerized Speech Laboratory (Kay Elemetrics) prior to cochlear implantation, at the time of implant activation and at 2 and 6 months postactivation. Assessments were based on sustained phonations and dynamic ranges.

MAIN OUTCOME MEASURE

Fundamental frequency, long-term control of fundamental frequency (vF0) and long-term control of amplitude (vAM) were derived from sustained phonations. The dynamic frequency range was derived from scale exercises. Formant frequencies (F1, F2, F3) were determined using linear predictive coding.

RESULTS

Fundamental frequency was not altered by implant activation or experience (P = 0.342). With profoundly deaf subject, the most prevalent acoustic abnormality was a poor long-term control of frequency (vF0, 2.81%) and long-term control of amplitude (vAm, 23.58%). Implant activation and experience had no effect on the long-term control of frequency (P = 0.106) but normalized the long-term control of amplitude (P = 0.007). The mean frequency range increased from 311.9 Hz preimplantation to 483.5 Hz postimplantation (P = 0.08). The F1/F2 ratio remained stable (P = 0.476).

CONCLUSION

In children, severe to profound deafness results in poor long-term control of frequency and amplitude. Cochlear implantation restores control of amplitude only and implies the need for additional rehabilitative strategies for restoration of control of frequency.

Atomic force microscopy investigation of isolated virions of murine leukemia virus

Virions of mouse leukemia virus spread on glass substrates were visualized by atomic force microscopy. The size distribution mode was 145 nm, significantly larger than that for human immunodeficiency virus particles. The distribution of particle sizes is broad, indicating that no two particles are likely identical in content or surface features. Virions possess knoblike protrusions, which may represent vestiges of budding from cell membranes. Particles which split open allowed imaging of intact cores with diameters of 65 nm. They also permitted estimation of viral shell thickness (35 to 40 nm) and showed the presence of a distinct trough between the shell and the core surface.

Atomic force microscopy imaging of retroviruses: human immunodeficiency virus and murine leukemia virus

Retroviruses are membrane-enveloped, RNA-containing viruses that produce a wide range of threatening diseases in higher animals. Among these are human immunodeficiency virus (HIV), which produces acquired immune deficiency syndrome (AIDS) in humans, and murine leukemia virus (MuLV), which produces leukemias in rodents. We have obtained the first atomic force microscopy (AFM) images of these two retroviruses, both isolated from culture media and emerging from infected cell surfaces. The HIV virions are 127 nm diameter on average, and those of MuLV are 145 nm, although there are wide distributions about the means. The AFM images show the arrangement of the envelope protein, responsible for host cell entry, on the surfaces of both virions. Disruption of the viruses using detergents or physical means allowed us to visualize interior structures, including the outer shells of both MuLV and HIV, the cores of MuLV, and the nucleic acid of HIV complexed with core proteins. Using immunolabeling techniques borrowed from electron microscopy, we were able to demonstrate the binding of gold-labeled antibodies directed against the envelope protein of MuLV. The AFM images are revealing, not only in terms of surface topology, but in terms of interior features as well, and they reveal the eccentricities and uniqueness of individual virus particles rather than yielding the average member of the population. Further application of AFM to viruses associated with other pathologies may ultimately have a significant impact on the diagnosis and treatment of virus-promoted diseases.

Atomic force microscopy investigation of wild-type Moloney murine leukemia virus particles and virus particles lacking the envelope protein

Moloney murine leukemia virus (M-MuLV) lacking the gene for the envelope glycoprotein (env(-)) was produced in NIH 3T3 cells and investigated using atomic force microscopy (AFM). The particles were compared with similarly produced wild-type virions, some of which had been exposed to a monoclonal antibody against the surface component of the envelope protein (SU protein). The env(-) particles generally exhibit a distinctly different external appearance suggesting only a low density of associated proteins that have an almost fluid, mechanically unstable character. The weakly associated proteins may be host cell membrane proteins that are incorporated into the viral membrane in place of or in addition to virus envelope protein. The amount of this non-viral protein on virion surfaces appears to vary from negligible in most cases to a substantial complement in others. It seems clear that the presence of the envelope protein, in a mechanical sense, significantly strengthens and stabilizes the virion envelope. Binding of monoclonal antibody to wild-type virions indicates that some particles expose a significant amount of antigen while adjacent virions may not. This suggests that the conformation of the envelope glycoprotein or the disposition of oligosaccharides may be different among particles, on some virions exposing the specific epitope, and others little or none.

What is true community-acquired urinary tract infection? Comparison of pathogens identified in urine from routine outpatient specimens and from community clinics in a prospective study

In order to identify the true nature of community-acquired urinary tract infections, the uropathogens isolated from 100 patients with urinary tract infection included in a prospective study conducted in community clinics were compared to 244 isolates from outpatient urine specimens routinely submitted to the laboratory. Significant differences in both the spectrum of bacteria and their antibiograms were found between the two groups. Laboratory data analysis of uropathogens from outpatient urine specimens may not reflect the true bacteriology of urinary tract infections acquired in the community. Hence, surveys based on laboratory data alone may overestimate resistance rates, leading to misinformed choices being made when treatment is empirical.

Fatal pulmonary haemorrhage with the combined use of abciximab and fibrinolytic agent

The increased bleeding risk associated with the use of abciximab has been well reported. The risk appears to be amplified when abciximab is administered concurrently with a fibrinolytic agent. We report and review the literature on the occurrence of a case of fatal pulmonary haemorrhage, a rare bleeding complication, in a patient who received both these drugs.

Intra-ureteric capsaicin in loin pain haematuria syndrome: efficacy and complications

OBJECTIVE

To evaluate the safety and efficacy of intra-ureteric capsaicin for loin pain haematuria syndrome (LPHS).

PATIENTS AND METHODS

In an open prospective pilot study, four middle-aged patients (three women and one man) with LPHS resistant to therapies such as splanchnic nerve block, psychological treatment or renal autotransplantation (one) were assessed. An intra-ureteric infusion of capsaicin (30 mg/100 mL of 30% alcohol in saline) for 30 min with bladder irrigation was administered under general anaesthesia, with a subsequent intravenous patient-controlled narcotic analgesic pump for pain control. Double-concentration capsaicin was used for second infusions, if necessary when the response to the earlier infusion was inadequate or incomplete.

RESULTS

The first patient had experienced reduced pain levels for the first 3 months only, with no benefit from the subsequent treatments with higher doses of capsaicin (60 mg). The second patient with recurrent pain in an autotransplanted kidney had no benefit from either a 30 or 60 mg capsaicin infusion a month apart, but developed a fibrotic stricture at the transplant pelvi-ureteric junction, requiring pyelocystoplasty. The third patient with concurrent depression had no benefit from a 30-mg infusion of capsaicin. The fourth patient experienced no pain relief from a 30 mg infusion of capsaicin but developed proteinuria secondary to mesangial proliferative glomerulonephritis, ureteric inflammation needing stenting within 7 days of treatment and subsequently nephrectomy for a nonfunctioning kidney at 3 months.

CONCLUSION

Intra-ureteric capsaicin was neither effective nor safe in LPHS; the contribution of the alcohol diluent cannot be excluded.

Influence of different biodegradable carriers on the in vivo behavior of human adipose precursor cells

The correction of soft-tissue defects presents a challenge in plastic and reconstructive surgery. The implantation of isolated and culture-expanded adipose precursor cells is a solution to this problem because these cells differentiate into adipocytes when implanted in vivo. Appropriate scaffolds are needed in soft-tissue engineering to allow the differentiation of precursor cells. The optimal carrier needs to be defined. In this study, human preadipocytes were isolated and cultured. Three different carrier materials were seeded with 106 preadipocytes each and implanted in 42 nude mice. Sponges and nonwoven carriers based on hyaluronic acid modified by esterification (HYAFF 11) were compared with collagen sponges. Scaffolds without cells served as negative controls in the same animal. After 3 and 8 weeks, the grafts were explanted. Macroscopic appearance, weight, thickness, microscopy, immunohistochemistry, and TEM (scaffold structure, cellularity, penetration depth of the seeded cells, vascularization) were assessed and evaluated for differences in scaffold-cell interactions.Preadipocytes differentiated earlier in vitro when attached to HYAFF 11 scaffolds than to other carrier materials. Macroscopically, all preadipocyte constructs were yellowish and well vascularized, and the controls were white and avascular. Vessel formation was more pronounced around mature adipocytes. Microscopically, HYAFF 11 constructs showed a higher cell density than collagen constructs. The pores of the sponges contained more differentiated adipocytes than the nonwoven carriers, whereas the undifferentiated preadipocytes were more numerous in the nonwoven material. Penetration of adipose precursor cells was deeper and more homogeneous in HYAFF 11 scaffolds. Electron microscopy demonstrated well-differentiated adipocytes and large amounts of extracellular matrix in HYAFF 11 sponges.HYAFF 11 sponges supported the expansion and differentiation of the adipose precursor cells. This carrier is superior to the nonwoven carrier with regard to adipocyte differentiation and superior to the collagen sponge with regard to cellularity. This is a promising method for the reconstruction of soft-tissue defects. Modifications of the scaffold (larger pore size and coating with adipogenic factors) will be examined in further experiments.