Latent Class Analysis Identifies Distinct Phenotypes of Systemic Lupus Erythematosus Predictive of Flares after mRNA COVID-19 Vaccination: Results from the Coronavirus National Vaccine Registry for ImmuNe Diseases SINGapore (CONVIN-SING)

We recently reported that messenger ribonucleic acid (mRNA) coronavirus disease 2019 (COVID-19) vaccination was associated with flares in 9% of patients with systemic lupus erythematosus (SLE). Herein, we focused our analysis on patients from a multi-ethnic Southeast Asian lupus cohort with the intention of identifying distinct phenotypes associated with increased flares after mRNA COVID-19 vaccination.

METHODS

Six hundred and thirty-three SLE patients from eight public healthcare institutions were divided into test and validation cohorts based on healthcare clusters. Latent class analysis was performed based on age, ethnicity, gender, vaccine type, past COVID-19 infection, interruption of immunomodulatory/immunosuppressive treatment for vaccination, disease activity and background immunomodulatory/immunosuppressive treatment as input variables. Data from both cohorts were then combined for mixed effect Cox regression to determine which phenotypic cluster had a higher risk for time to first SLE flare, adjusted for the number of vaccine doses.

RESULTS

Two clusters were identified in the test (C1 vs. C2), validation (C1' vs. C2') and combined (C1″ vs. C2″) cohorts, with corresponding clusters sharing similar characteristics. Of 633 SLE patients, 88.6% were female and there was multi-ethnic representation with 74.9% Chinese, 14.2% Malay and 4.6% Indian. The second cluster (C2, C2' and C2″) was smaller compared to the first. SLE patients in the second cluster (C2 and C2') were more likely to be male, non-Chinese and younger, with higher baseline disease activity. The second cluster (C2″) had more incident flares (hazard ratio = 1.4, 95% confidence interval 1.1-1.9, p = 0.014) after vaccination. A higher proportion of patients in C2″ had immunomodulatory/immunosuppressive treatment interruption for vaccination as compared to patients in C1″ (6.6% vs. 0.2%) (p < 0.001).

CONCLUSION

We identified two distinct phenotypic clusters of SLE with different patterns of flares following mRNA COVID-19 vaccination. Caution has to be exercised in monitoring for post-vaccination flares in patients with risk factors for flares such as non-Chinese ethnicity, young age, male gender and suboptimal disease control at the time of vaccination.

Prevalence and factors associated with flares following COVID-19 mRNA vaccination in patients with rheumatoid arthritis, psoriatic arthritis and spondyloarthritis: a national cohort study

OBJECTIVE

To determine prevalence and factors associated with flares post Coronavirus disease 2019 (COVID-19) mRNA vaccination in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and spondyloarthritis (SpA).

METHODS

A retrospective multi-centre study was conducted (January 2021 to February 2022). Data were collected during index visit, defined as first post-vaccine visit in which the patient had a physician-defined flare, or if at least 3 months had elapsed since first vaccine dose, whichever came first. Factors associated with flares were identified using mixed effects Cox regression and expressed as hazard ratio (HR) and 95% confidence interval (CI).

RESULTS

Total of 2377 patients were included (1563 RA, 415 PsA and 399 SpA). Among patients with RA, PsA and SpA, 21.3%, 24.1% and 21.8% experienced a flare respectively. Of those who experienced a flare, only 10.2%, 11.0% and 14.9% were severe in patients with RA, PsA and SpA respectively. Patients with low or moderate/high disease were more likely to flare compared to those in remission in patients with RA only (HR: 1.68, 95% CI 1.22-2.31; HR: 2.28, 95% CI 1.50-3.48, respectively). Receiving the Moderna vaccine was associated with a higher HR of flare compared to the Pfizer vaccine in patients with PsA only (HR: 2.21, 95% CI 1.20-4.08). Patients who had two vaccine doses were found to be less likely to flare (HR: 0.08, 95% CI 0.06-0.10). HRs of flares were not significantly different among RA, PsA and SpA.

CONCLUSION

About one-fifth of patients experienced a disease flare post COVID-19 mRNA vaccination, but most flares were non-severe. Patients with active disease prior to vaccination should be monitored closely for disease flares, especially in patients with RA.

Recommendations for enhanced primary series (third dose) COVID-19 vaccination for people with rheumatic diseases: Chapter of Rheumatologists, College of Physicians, Singapore

Introduction

This review aims to provide evidence-based recommendations for an enhanced primary series (third dose) coronavirus disease 2019 (COVID-19) vaccination in people with rheumatic diseases (PRDs) in the local and regional context.

Methods

Literature reviews were performed regarding the necessity, efficacy, safety and strategies for enhanced primary series COVID-19 vaccination in PRDs. Recommendations were developed based on evidence according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. Evidence was synthesised by eight working group members, and the consensus was achieved by a Delphi method with nine members of an expert task force panel.

Results

Two graded recommendations and one ungraded position statement were developed. PRDs have impaired immunogenicity from the COVID-19 vaccine and are at an increased risk of postvaccine breakthrough severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and poor clinical outcomes, compared to the general population. We strongly recommend that PRDs on immunomodulatory drugs be offered a third dose of the messenger RNA (mRNA) vaccine as part of an enhanced primary series, after the standard two-dose regimen. We conditionally recommend that the third dose of mRNA vaccine against SARS-CoV-2 be given at least 4 weeks after the second dose or as soon as possible thereafter. There is insufficient data to inform whether the third mRNA vaccine should be homologous or heterologous in PRDs.

Conclusion

These recommendations that were developed through evidence synthesis and formal consensus process provide guidance for an enhanced primary series COVID-19 vaccination in PRDs.

mHealth App to Facilitate Remote Care for Patients With COVID-19: Rapid Development of the DrCovid+ App

BACKGROUND

The 2019 novel COVID-19 has severely burdened the health care system through its rapid transmission. Mobile health (mHealth) is a viable solution to facilitate remote monitoring and continuity of care for patients with COVID-19 in a home environment. However, the conceptualization and development of mHealth apps are often time and labor-intensive and are laden with concerns relating to data security and privacy. Implementing mHealth apps is also a challenging feat as language-related barriers limit adoption, whereas its perceived lack of benefits affects sustained use. The rapid development of an mHealth app that is cost-effective, secure, and user-friendly will be a timely enabler.

OBJECTIVE

This project aimed to develop an mHealth app, DrCovid+, to facilitate remote monitoring and continuity of care for patients with COVID-19 by using the rapid development approach. It also aimed to address the challenges of mHealth app adoption and sustained use.

METHODS

The Rapid Application Development approach was adopted. Stakeholders including decision makers, physicians, nurses, health care administrators, and research engineers were engaged. The process began with requirements gathering to define and finalize the project scope, followed by an iterative process of developing a working prototype, conducting User Acceptance Tests, and improving the prototype before implementation. Co-designing principles were applied to ensure equal collaborative efforts and collective agreement among stakeholders.

RESULTS

DrCovid+ was developed on Telegram Messenger and hosted on a cloud server. It features a secure patient enrollment and data interface, a multilingual communication channel, and both automatic and personalized push messaging. A back-end dashboard was also developed to collect patients' vital signs for remote monitoring and continuity of care. To date, 400 patients have been enrolled into the system, amounting to 2822 hospital bed-days saved.

CONCLUSIONS

The rapid development and implementation of DrCovid+ allowed for timely clinical care management for patients with COVID-19. It facilitated early patient hospital discharge and continuity of care while addressing issues relating to data security and labor-, time-, and cost-effectiveness. The use case for DrCovid+ may be extended to other medical conditions to advance patient care and empowerment within the community, thereby meeting existing and rising population health challenges.

Post-mRNA vaccine flares in autoimmune inflammatory rheumatic diseases: Results from the COronavirus National Vaccine registry for ImmuNe diseases SINGapore (CONVIN-SING)

BACKGROUND

Studies of flares of autoimmune inflammatory rheumatic diseases (AIIRD) after COVID-19 mRNA vaccination are limited by small sample size, short follow up or at risk of selection bias.

METHODS

A national retrospective cohort study of consecutive AIIRD patients ≥12 years old, across 8 hospitals who received at least one dose of a COVID-19 mRNA vaccine. Patients were included from the date of 1st vaccine dose and censored at the time of flare or on the date of the clinic visit at least 3 months from cohort entry, whichever came first. Predictors of flare were determined by Cox proportional hazards analysis.

FINDINGS

4627 patients (73% Chinese, 71% female) of median (IQR) age 61 (48, 70) years were included; 42% Rheumatoid arthritis, 14% Systemic lupus erythematosus and 11% Psoriatic arthritis. 47% were in remission, 41% low disease activity, 10% moderate disease activity and 1% in high disease activity. 18% patients flared, of which 11.7% were within the 3-month period of interest. 11.8% patients improved. Median (IQR) time-to-flare was 60 (30, 114) days. 25% flares were self-limiting, 61% mild-moderate and 14% severe. Older patients (53-65 years and >66 years) had a lower risk of flare [HR 0.6 (95% CI 0.5-0.8) and 0.7 (0.6-0.8) respectively]. Patients with inflammatory arthritis and with active disease had a higher risk of flare [HR 1.5 (1.2-2.0) and 1.4 (1.2-1.6), respectively]. Treatment with conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs), immunosuppression and prednisolone was also associated with an increased risk of flare [HR 1.5 (1.1-2), 1.2 (1.1-1.4) and 1.5 (1.2-1.8) for prednisolone ≤7.5 mg respectively].

INTERPRETATION

There was a moderately high rate of AIIRD flares after mRNA vaccination but also improvement in several patients. Severe flares and hospitalisation were rare. Thus, vaccination remains safe and highly recommended.

The role of echocardiography in the diagnosis of adult patients with myocarditis: a systematic review and meta-analysis

Funding Acknowledgements

Type of funding sources: None.

Background

Transthoracic echocardiography (TTE) plays a key diagnostic role in the initial work-up of patients presenting with myocarditis. Its utility in myocarditis is for identification of structural and functional changes, which may assist with diagnosis, surveillance and prognostication.

Purpose

The purpose of this systematic review and meta-analysis was to appraise the evidence associated with the use of echocardiography for the diagnosis of myocarditis in adults.

Methods

A systematic literature search of medical databases including Pubmed, Ovid Online, EMBASE, Web of Science, Cochrane Central Register of Controlled Trials, Scopus, ProQuest, Science Direct and grey literature was performed using PRISMA principles to identify all relevant TTE studies on myocarditis in adult patients (1995-2020; English only; PROSPERO registration CRD42021243598). Data for a range of TTE parameters were individually extracted and then meta-analysed using a random-effects model for overall effect size through standard mean difference (SMD).

Results

Of the 13 relevant studies, 6 were included and revealed that myocarditis can be reliably differentiated from healthy controls, both in the acute and sub-acute phase by left ventricular (LV) global longitudinal strain, and less so by LV ejection fraction and LV end-diastolic volume (p &lt; 0.05 for all). See Table. LV-GLS demonstrated the strongest ability to discriminate myocarditis patients from healthy controls when compared to standard two-dimensional measures of LV size and function (p &lt; 0.05).

Conclusions

LV-GLS demonstrated the best discriminatory ability for differentiation of myocarditis from adult healthy controls. Further research is required to characterize the utility of these quantitative parameters in the diagnostic work-up of these patients. Abstract Figure.

Uptake of echocardiography amongst different risk groups for patients treated with cardiotoxic chemotherapy

Funding Acknowledgements

Type of funding sources: None.

Background

Cardiovascular complications of cancer therapy are increasingly becoming a significant medical issue. Hence, the role of cardiovascular imaging in the assessment of baseline cardiovascular risk is becoming increasingly important. Current guidelines recommend a baseline transthoracic echocardiogram (TTE) prior to commencement of cardiotoxic chemotherapy (CC) but the uptake is presently inconsistent.

Purpose

Our study aimed to determine the uptake of a baseline TTE in a cohort of patients with solid organ malignancies (SOM) prior to commencing their treatment and to examine the patterns of uptake based on the risk of development of cardiotoxicity.

Methods

Patients with a SOM admitted to our institution between 2014-18 were examined. Demographic data, clinical comorbidities, cancer type, and chemotherapeutic regimens used were obtained from the patient’s electronic medical record. Included patients were divided into those receiving one of the 8 CC classes identified in the Cardio-Oncology Study Group and International Cardio-Oncology Society (COSG/ICOS) 2020 position statement1, and those who did not (control group). Those receiving CC were further stratified into risk groups according to the proformas proposed by the COSG/ICOS, while patients receiving immunotherapy for whom a proforma was not available, were considered a separate group. The uptake patterns of TTE in each group determined.

Results

Of 800 patients reviewed, 712 patients were included, and categorised into groups as shown in figure 1. Patients treated with CC had low uptake of a baseline TTE, and there was no difference compared to controls (14.4% vs 13.9%, p = 0.9). They were however more likely to have received a TTE during the course of treatment (32.3% vs 23.2%, p = 0.009). Figure 2 shows the rates of baseline TTE stratified by risk group. Compared to patients not on CC, only very high risk patients had a higher rate of baseline TTE (p &lt; 0.001), while low risk patients had lower rates (p = 0.005). Compared to those not on CC, there was no difference in the rate of baseline TTE amongst immunotherapy patients, medium risk and high risk patients.

Conclusion

The uptake of baseline TTE in accordance with guidelines amongst patients receiving CC was very low. Based on the risk stratification proformas proposed by the COSG/ICOS, only very high risk patients were having a baseline TTE more frequently than those not treated with CC. The risk of future cardiotoxicity amongst low, medium and high risk patients, and those receiving immunotherapy, appears to be underappreciated, as these patients were not screened by TTE prior to commencing therapy. Increasing awareness of the agents that cause cardiotoxicity, and the establishment of formal protocols for these patients, may increase compliance with recommendations for TTE prior to commencing CC. Abstract Figure. Distribution of patients by risk group  Abstract Figure. Percentage of patients with baseline TTE

Serial measurement of global longitudinal strain among women with breast cancer treated with proton radiation therapy

Background

Conventional photon radiotherapy (RT) for breast cancer is associated with reduction in global longitudinal strain (GLS), an increase in both troponin and N-terminal pro-B type natriuretic peptide (NT-proBNP), and incident heart failure. The cardiac radiation exposure with proton-RT is reduced and, thus may be associated with less cardiotoxicity.

Objectives

To test the effect of proton-RT on GLS, troponin and NT-proBNP.

Methods

A prospective observational single center study of 69 women being treated with proton-RT for breast cancer. Serial measurements of GLS, high-sensitivity cardiac troponin-I (hs-cTnI), and NT-proBNP were performed at pre-specified intervals (pre proton-RT, 4 weeks after completion of proton-RT and again at 2 months post proton-RT).

Results

The mean age was 46±11 years, BMI was 25.6±5.2 kg/m2, 32% had hypertension and mean radiation dose to the heart and left ventricle (LV) were 0.44 Gy and 0.12 Gy respectively. There was no change in LV ejection fraction (pre proton-RT vs. 4-weeks post proton-RT vs. 2 months post proton-RT, 65±5 vs. 66±5 vs. 64±4%, p=0.15), global GLS (−21.7±2.7 vs. −22.7±2.3 vs. −22.8±2.1%, p=0.24) or segmental GLS from pre-to post proton-RT. Similarly, there was no change in hs-cTnI or NT-proBNP with proton-RT. However, post proton-RT, we found that patients with a history of hypertension had lower GLS when compared to women without hypertension (−21.3±3.5 vs. −24.0±2.4%, p=0.006).

Conclusion

Proton-RT did not impact LV function, or associate with an increase in biomarkers. These data support the potential cardiac benefits of proton-RT compared to conventional RT.

Funding Acknowledgement

Type of funding sources: None.

LV-GLS is a predictor of all-cause death and cardiovascular MACE events in patients with neuro-immunological disorders

Background

Neuro-immunological disorders encompass several disease states, including multiple sclerosis (MS), autoimmune encephalitis (AE) and myasthenia gravis (MG). These autoimmune conditions are mediated via pro-inflammatory cytokines, and there is growing evidence to suggest cardiovascular involvement within these inflammatory states. Left ventricular global longitudinal strain (LV-GLS) is proposed to be a more sensitive measure of LV systolic function when compared to standard two-dimensional measures such as LV ejection fraction (LVEF).

Purpose

The purpose of this study was to assess for subclinical cardiac dysfunction in a cohort of patients with neuro-immunological disorders and correlate this with the development of outcomes on follow-up.

Methods

Consecutive patients with MS, AE and MG admitted to our institution during 2013–2020 were assessed (n=102). Patients without pre-existing cardiovascular disease, LVEF &lt;50% or lack of comprehensive transthoracic echocardiography during their index admission were included (n=55). This group was compared to age- and gender-matched controls (n=55) LV-GLS was measured offline using vendor-independent software (TomTec Arena, Germany v4.6) by two cardiologists blinded to the patient group or outcomes. These patients were followed for up for the composite outcome of all-cause death and major adverse cardiovascular events (MACE).

Results

A total of 55 patients (31 MS, 14 AE and 10 MG) were age- and gender- matched to 55 controls. There was no significant difference in baseline demographic characteristics or cardiovascular risk factors between groups. Patients with neuro-immunological disorders demonstrated impaired LV-GLS (−17.6±3.5 vs −20.8±1.9; p&lt;0.01) when compared to healthy controls, despite an LVEF within the normal range (60.9±7.7 vs 64.1±5.7; p=0.02) in both groups. There were a total of 9 (16.4%) outcomes during a mean follow-up of 41.0±33.0 months. LV-GLS was the only significant echocardiographic predictor of all-cause death and MACE events (p=0.013) on multi-variate analysis.

Conclusions

Our results suggest that patients with neuro-immunological disorders have subclinical LV dysfunction as assessed by LV-GLS which has prognostic capacity in this population. Further larger studies are required to further characterize this phenomenon.

Funding Acknowledgement

Type of funding sources: None.

Patients with rare autoimmune inflammatory disorders demonstrate sub-clinical left ventricular dysfunction

Background

ANCA-associated Vasculitis (AAV) and inflammatory myositis (IM) are rare inflammatory autoimmune disorders mediated via pro-inflammatory cytokines and result in a systemic inflammatory state with multi-organ involvement. There is growing evidence to suggest cardiovascular involvement within these inflammatory states. Left ventricular global longitudinal strain (LV-GLS) is proposed to be a more sensitive measure of LV systolic function when compared to standard two-dimensional measures such as LV ejection fraction (LVEF).

Purpose

The purpose of this study was to assess for subclinical cardiac dysfunction in these cohorts when compared to controls.

Methods

Consecutive patients with AAV (n=56) and IM (n=68) admitted to our institution during 2013–2021 were assessed. Patients with pre-existing cardiovascular disease, significant renal impairment (eGFR &lt;30mL/min/1.73m2), LVEF &lt;50% or lack of comprehensive transthoracic echocardiography during admission were excluded (n=72). LV-GLS was measured offline using vendor-independent software (TomTec Arena, Germany v4.6).

Results

A total of 52 patients (22 AAV and 30 IM) were age- and gender-matched to 52 controls. In comparison of the two study populations (AAV and IM), patients with AAV had higher rates of renal impairment (p=0.02) but lower rates of interstitial lung disease when compared to IM (p=0.02). There were no differences between the two groups in terms of cardiovascular risk factors, demographics or other laboratory investigations (p&gt;0.05 for all). In comparison to the control population, patients with AAV and IM had higher indexed LV mass and a lower TAPSE, respectively, when compared to controls. These cohorts also demonstrated impaired LV-GLS (−17.7±2.6 vs −20.6±2.4; p&lt;0.01) when compared to healthy controls, despite no differences in LVEF (62.6±7.8 vs 61.8±5.4; p=0.56) between both groups.

Conclusions

Our results suggest that patients with autoimmune inflammatory disorders demonstrate subclinical LV dysfunction which is likely secondary to a chronic inflammatory state.

Funding Acknowledgement

Type of funding sources: None.

Application of a BMP2-binding heparan sulphate to promote periodontal regeneration

Periodontitis is the most common inflammatory disease that leads to periodontal defects and tooth loss. Regeneration of alveolar bone and soft tissue in periodontal defects is highly desirable but remains challenging. A heparan sulphate variant (HS3) with enhanced affinity for bone morphogenetic protein-2 (BMP2) that, when combined with collagen or ceramic biomaterials, enhances bone tissue regeneration in the axial and cranial skeleton in several animal models was reported previously. In the current study, establishing the efficacy of a collagen/HS3 device for the regeneration of alveolar bone and the adjacent periodontal apparatus and related structures was sought. Collagen sponges loaded with phosphate-buffered saline, HS3, BMP2, or HS3 + BMP2 were implanted into surgically-created intra-bony periodontal defects in rat maxillae. At the 6 week end- point the maxillae were decalcified, and the extent of tissue regeneration determined by histomorphometrical analysis. The combination of collagen/HS3, collagen/BMP2 or collagen/HS3 + BMP2 resulted in a three to four-fold increase in bone regeneration and up to a 1.5 × improvement in functional ligament restoration compared to collagen alone. Moreover, the combination of collagen/HS3 + BMP2 improved the alveolar bone height and reduced the amount of epithelial growth in the apical direction. The implantation of a collagen/ HS3 combination device enhanced the regeneration of alveolar bone and associated periodontal tissues at amounts comparable to collagen in combination with the osteogenic factor BMP2. This study highlights the efficacy of a collagen/HS3 combination device for periodontal regeneration that warrants further development as a point-of-care treatment for periodontitis-related bone and soft tissue loss.

Recommendations for COVID-19 vaccination in people with rheumatic disease: Developed by the Singapore Chapter of Rheumatologists

Aim

People with rheumatic diseases (PRD) remain vulnerable in the era of the COVID‐19 pandemic. We formulated recommendations to meet the urgent need for a consensus for vaccination against SARS‐CoV‐2 in PRD.

Methods

Systematic literature reviews were performed to evaluate: (a) outcomes in PRD with COVID‐19; (b) efficacy, immunogenicity and safety of COVID‐19 vaccination; and (c) published guidelines/recommendations for non‐live, non‐COVID‐19 vaccinations in PRD. Recommendations were formulated based on the evidence and expert opinion according to the Grading of Recommendations Assessment, Development and Evaluation methodology.

Results

The consensus comprises 2 overarching principles and 7 recommendations. Vaccination against SARS‐CoV‐2 in PRD should be aligned with prevailing national policy and should be individualized through shared decision between the healthcare provider and patient. We strongly recommend that eligible PRD and household contacts be vaccinated against SARS‐CoV‐2. We conditionally recommended that the COVID‐19 vaccine be administered during quiescent disease if possible. Immunomodulatory drugs, other than rituximab, can be continued alongside vaccination. We conditionally recommend that the COVID‐19 vaccine be administered prior to commencing rituximab if possible. For patients on rituximab, the vaccine should be administered a minimum of 6 months after the last dose and/or 4 weeks prior to the next dose of rituximab. Post‐vaccination antibody titers against SARS‐CoV‐2 need not be measured. Any of the approved COVID‐19 vaccines may be used, with no particular preference.

Conclusion

These recommendations provide guidance for COVID‐19 vaccination in PRD. Most recommendations in this consensus are conditional, reflecting a lack of evidence or low‐level evidence.

Viral arthralgia a new manifestation of COVID-19 infection? A cohort study of COVID-19-associated musculoskeletal symptoms

Objectives

Musculoskeletal symptoms are often unrecognised as a prominent feature of COVID-19 infection. This study hypothesised that viral arthralgia is an uncommon but distinct manifestation of COVID-19 infection. In addition, it aimed to characterise the other musculoskeletal presentations of COVID-19 infection and study their prognostic implications.

Methods

Patients hospitalised with COVID-19 infection were divided into two groups: those with and without musculoskeletal symptoms. Those with musculoskeletal symptoms were subdivided according to four patterns of musculoskeletal involvement: myalgia, arthralgia, backache and generalised body ache. Using binary regression logistic analysis, the risk of developing a viral pneumonia in patients with and without musculoskeletal complaints was compared.

Results

Of 294 hospitalised patients with COVID-19, 88 (30%) reported musculoskeletal complaints. Among these 88 patients, 37.5% had myalgia, 5.7% arthralgia, 6.8% new-onset backache and 50% generalised body ache. The presence of musculoskeletal complaints was not associated with the risk of developing viral pneumonia (6.8% vs. 9.7%, OR 0.68, 95% CI 0.26–1.76, p = 0.426). COVID-19 arthralgia was often more severe and had variable onset, while generalised body ache and myalgia were milder and coincided with the occurrence of fever or respiratory symptoms.

Conclusion

Viral arthralgia is a novel clinical manifestation of COVID-19, and untypical of a viral prodrome or a reactive arthropathy. While musculoskeletal symptoms were not associated with developing a pneumonia, to avoid missing a diagnosis of COVID-19, clinicians should be aware of its variable onset, particularly when respiratory symptoms are absent at the time of presentation.

Antivirals With Adjunctive Corticosteroids Prevent Clinical Progression of Early Coronavirus 2019 Pneumonia: A Retrospective Cohort Study

This is a retrospective cohort study of hospitalized adults with coronavirus disease 2019 (COVID-19). Fifty-seven patients received treatment alone, and 35 patients received treatment with adjunctive prednisolone. A combination of corticosteroids and antivirals was associated with lower risk of clinical progression and invasive mechanical ventilation or death in early COVID-19 pneumonia.

The clinical utility of anti-DFS70 for identifying antinuclear antibody-positive patients without systemic autoimmune rheumatic disease

INTRODUCTION

The antinuclear antibody (ANA) test is a screening test for systemic autoimmune rheumatic disease (SARD). We hypothesised that the presence of anti-DFS70 in ANA-positive samples was associated with a false-positive ANA test and negatively associated with SARD.

METHODS

A retrospective analysis of patient samples received for ANA testing from 1 January 2016 to 30 June 2016 was performed. Patient samples underwent ANA testing via indirect immunofluorescence method and anti-DFS70 testing using enzyme-linked immunosorbent assay.

RESULTS

Among a total of 645 ANA-positive samples, the majority (41.7%) was positive at a titre of 1:80. The commonest nuclear staining pattern was speckled (65.5%). Only 9.5% of ANA-positive patients were diagnosed with SARD. Anti-DFS70 was found to be present in 10.0% of ANA-positive patients. The majority (51/59 patients, 86.4%) of patients did not have SARD. Seven patients had positive ANA titre > 1:640, presence of anti-double stranded DNA and/or anti-Ro60. The presence of anti-DFS70 in ANA-positive patients was not associated with the absence of SARD (Fisher's exact test, p = 0.245).

CONCLUSION

The presence of anti-DFS70 was associated with a false-positive ANA test in 8.6% of our patients. Anti-DFS70 was not associated with the absence of SARD.

Singapore Chapter of Rheumatologists updated consensus statement on the eligibility for government subsidization of biologic and targeted-synthetic therapy for the treatment of rheumatoid arthritis

INTRODUCTION

Approximately 30% of patients with rheumatoid arthritis (RA) respond inadequately to conventional-synthetic disease-modifying anti-rheumatic drugs (csDMARDs). However, widespread use of biologic DMARDs (bDMARDs) and targeted-synthetic (tsDMARDs) is limited by cost. We formulated updated recommendations for eligibility criteria for government-assisted funding of bDMARDs/tsDMARDs for RA patients in Singapore.

MATERIALS AND METHODS

Published guidelines regarding use of bDMARD and tsDMARDs were reviewed. We excluded those without a systematic literature review, formal consensus process or evidence grading. Separately, unpublished national reimbursement guidelines were included.

RESULTS

Eleven recommendations regarding choice of disease activity measure, initiation, order of selection and continuation of bDMARD/tsDMARDs were formulated. A bDMARD/tsDMARD is indicated if a patient has: (a) at least moderately active RA with a Disease Activity Score in 28 joints/erythrocyte sedimentation rate (DAS28-ESR) score of ≥3.2; (b) failed ≥2 csDMARD strategies, 1 of which must be a combination; (c) received an adequate dose regimen of ≥3 months for each strategy. For the first-line bDMARD/tsDMARD, either tumor necrosis factor inhibitors (TNFi), non-TNFi (abatacept, tocilizumab, rituximab), or tsDMARDs, may be considered. If a first-line TNFi fails, options include another TNFi, non-TNFi biologic or tsDMARDs. If a first-line non-TNFi biologic or tsDMARD fails, options include TNFi or another non-TNF biologic or tsDMARD. For continued bDMARD/tsDMARD subsidization, a patient must have a documented DAS28-ESR every 3 months and at least a moderate European League Against Rheumatism response by 6 months.

CONCLUSION

These recommendations are useful for guiding funding decisions, making bDMARD/tsDMARDs usage accessible and equitable in RA patients who fail csDMARDs.

P2468Clinical and cardiac structural differences between paroxysmal and persistent/permanent non-valvular atrial fibrillation

Background

Atrial Fibrillation (AF) is a heterogeneous condition and is traditionally classified by duration (paroxysmal, persistent and permanent). There is a relationship between AF and left atrial (LA) remodeling, with increased likelihood of AF recurrence and maintenance with increasing LA volumes.

Purpose

To assess clinical and cardiac structural differences between the subtypes of AF.

Methods

We examined 1247 (68±13.4y; 50% men) consecutive admissions presenting to our institution with the primary diagnosis of AF. Repeat admissions (n=263) were excluded. Of remaining 984 subjects, a majority had diagnosed paroxysmal (72.2%), with lower numbers of persistent (23.4%) and permanent (4.4%) AF. Echo parameters of cardiac chamber size and function were examined in a subset of subjects with complete echo (n=646) performed during incident hospital admission.

Results

There were significantly higher rates of diabetes mellitus (p=0.03), ischaemic heart disease (IHD; p=0.04) and peripheral vascular disease (PVD; p=0.02) in those with persistent/permanent AF compared to paroxysmal AF. No significant differences in age (p=0.19), BMI (p=0.42), OSA (p=0.05), or hypertension (p=0.76) was noted. There were significant differences in left ventricular (LV) mass and systolic function, LA size and function between the two groups (Table 1). Receiver operator curve analysis revealed that LAEF was a discriminator for persistent/permanent AF with an area under the curve of 0.689 (95% CI, 0.646 to 0.732; p<0.001).

Echo parameters in AF subtype Echocardiographic Parameters Paroxysmal AF (n=433) Persistent and Permanent AF (n=213) Significance (p value) LVEDD (cm) 4.8±3.0 5.0±0.9 0.29 LVESD (cm) 3.3±1.3 3.7±1.1 <0.01 IVS thickness (cm) 1.2±0.7 1.1±0.3 0.44 PW thickness (cm) 1.1±0.7 1.1±0.2 0.77 LV mass (g) 92.3±28.3 108.2±35.3 <0.01 LVEF (%) 56.1±14.1 47.4±16.8 <0.01 LA Expansion Index 89.4±69.1 53.4±40.3 <0.01 Min LA Volume indexed (ml/m2) 18.9±17.2 27.3±20.6 0.01 Max LA Volume indexed (ml/m2) 32.5±19.2 37.7±15.3 <0.01 LAEF (%) 41.8±16.4 31.5±13.6 <0.01

Conclusions

Our results suggest diabetes, IHD and PVD are associated with persistent/permanent AF. Additionally, greater LA remodeling and reduced atrial function was noted in this group, suggestive of an association between duration of AF electrical burden and LA remodeling and function.

Prevalence and risk factors of Toxoplasma infection - an update in Malaysian pregnant women

Toxoplasma gondii is a protozoan parasite that is capable of causing a zoonotic disease, known as toxoplasmosis. Vertical transmission of T. gondii from the mother to the fetus, during pregnancy may cause severe complications to the developing fetus. This current study aimed to determine the seroprevalence and investigate the associated risk factors of Toxoplasma infection in pregnant women (n=219) visiting the antenatal clinic at UMMC. While the elevated level of anti-Toxoplasma IgG and IgM antibodies indicates the presence of infection, it fails to differentiate between a past and a recent infection. Thus, the study also demonstrates the usefulness of IgG avidity in validating the timing of infection. The serum samples were tested for the presence of anti-Toxoplasma IgG and IgM antibodies by ELISA test, and the seropositive samples for both anti-Toxoplasma IgG and IgM antibodies were further evaluated by IgG avidity. The results showed that the overall prevalence of T. gondii seropositivity was 34.7%. Of these, 30.6% (67/219) were positive for anti-Toxoplasma IgG antibody only, 2.3% (5/219) were positive for anti-Toxoplasma IgM only, and the remaining 1.8% (4/219) was positive for both anti-Toxoplasma IgG and IgM antibodies. All of the pregnant women who were positive for both anti-Toxoplasma IgG and IgM antibody were found to have past infection when evaluated by IgG avidity. In this study, Malay ethnicity and the number of existing previous children were significantly associated with T. gondii seropositivity (p<0.05). Based on these findings, information and education on the transmission and prevention of congenital toxoplasmosis are very crucial as a public health effort towards a healthier society.

Impact of an interstitial lung disease service in the diagnosis and management of interstitial lung disease in Singapore

INTRODUCTION

The current gold standard for diagnosing interstitial lung disease (ILD) involves an ILD clinic evaluation, followed by discussion in a multidisciplinary meeting (MDM). However, there is a paucity of data on the impact of ILD MDMs on the diagnosis and management of ILDs in Southeast Asia. We studied the clinical impact of the ILD service on the diagnosis and management of ILDs at a university-affiliated tertiary hospital in Singapore.

METHODS

A single-centre retrospective review was done on 97 consecutive patients referred for evaluation to the ILD service from March 2016 to August 2017.

RESULTS

Mean age of the patients was 67 ± 11 years. Gender distribution was almost equal (52% male), with a majority of never-smokers (63%). Mean forced vital capacity (FVC) was 1.81 ± 0.66 L (66% ± 20% predicted). The three commonest referral diagnoses were ILD of uncertain classification (n = 38, 39%), connective tissue disease-associated ILD (CTD-ILD) (n = 24, 25%) and idiopathic pulmonary fibrosis (IPF) (n = 16, 17%). Following evaluation by the ILD service, there was a change of diagnosis in 60 (62%) patients and a change of management in 71 (73%) patients. The majority of consensus MDM diagnoses were IPF (n = 35, 36%), CTD-ILD (n = 30, 30%) and others (n = 15, 15%). There was a significant prognostic separation between the IPF and non-IPF diagnoses made following evaluation by the ILD service.

CONCLUSION

The ILD service allowed for more precise subtyping of various ILDs. This is particularly useful for IPF patients, who can benefit from antifibrotic therapies.

Autologous bone marrow clot as an alternative to autograft for bone defect healing

Objectives

Long bone defects often require surgical intervention for functional restoration. The ‘gold standard’ treatment is autologous bone graft (ABG), usually from the patient’s iliac crest. However, autograft is plagued by complications including limited supply, donor site morbidity, and the need for an additional surgery. Thus, alternative therapies are being actively investigated. Autologous bone marrow (BM) is considered as a candidate due to the presence of both endogenous reparative cells and growth factors. We aimed to compare the therapeutic potentials of autologous bone marrow aspirate (BMA) and ABG, which has not previously been done.

Methods

We compared the efficacy of coagulated autologous BMA and ABG for the repair of ulnar defects in New Zealand White rabbits. Segmental defects (14 mm) were filled with autologous clotted BM or morcellized autograft, and healing was assessed four and 12 weeks postoperatively. Harvested ulnas were subjected to radiological, micro-CT, histological, and mechanical analyses.

Results

Comparable results were obtained with autologous BMA clot and ABG, except for the quantification of new bone by micro-CT. Significantly more bone was found in the ABG-treated ulnar defects than in those treated with autologous BMA clot. This is possibly due to the remnants of necrotic autograft fragments that persisted within the healing defects at week 12 post-surgery.

Conclusion

As similar treatment outcomes were achieved by the two strategies, the preferred treatment would be one that is associated with a lower risk of complications. Hence, these results demonstrate that coagulated BMA can be considered as an alternative autogenous therapy for long bone healing.

Cite this article: Z. X. H. Lim, B. Rai, T. C. Tan, A. K. Ramruttun, J. H. Hui, V. Nurcombe, S. H. Teoh, S. M. Cool. Autologous bone marrow clot as an alternative to autograft for bone defect healing. Bone Joint Res 2019;8:107–117. DOI: 10.1302/2046-3758.83.BJR-2018-0096.R1.

Genetic diversity of Merozoite Surface Protein-1 gene block 2 allelic types in Plasmodium falciparum isolates from Malaysia and Thailand

Malaria is the most common vector-borne parasitic disease in Malaysia and Thailand, especially in Malayan Borneo and along the Thailand border areas, but little is known about the genetic diversity of the parasite. Present study aims to investigate the genetic diversity of Plasmodium falciparum isolates in these two countries and eventually contributes to more effective malaria control strategies, particularly in vaccine and antimalarial treatment. One hundred and seventy three P. falciparum isolates were collected from Malaysia (n = 67) and Thailand (n = 106) and genotyped using nested PCR targeting the polymorphic region of MSP-1, block 2. Sequence analysis was conducted to investigate the allele diversity of the isolates. Three allelic families were identified in Malaysian and Thailand P. falciparum isolates, MAD20, K1 and RO33. Sequence analysis revealed that there were 5 different MAD20, 1 K1 and 2 different RO33 for Malaysian isolates. Thailand isolates exhibited greater polymorphism because there were 13 different MAD20, 6 different K1 and 2 different RO33 identified in this study. Multiclonal infections were observed for the isolates in both countries, however, low multiplicity of infection (MOI) was observed for Malaysian (1.1) and Thailand (1.2) isolates. Phylogenetic analysis showed that P. falciparum isolates of Malaysia and Thailand were clustered in the same group for all the allelic families. Population structure of P. falciparum isolates in Malaysia and Thailand exhibit extensive genetic polymorphism but showed high similarities as well as comparable MOI.

DNA barcoding relates Trichuris species from a human and a man's best friend to non-human primate sources

Trichuris trichiura, the whipworm of humans, is one of the most prevalent soiltransmitted helminths (STH) reported worldwide. According to a recent study, out of 289 STH studies in Southeast Asia, only three studies used molecular methods. Hence, the genetic assemblages of Trichuris in Southeast Asia are poorly understood. In this study, we used partial mitochondrial DNA (cytochrome c oxidase subunit 1 or COI) sequences for analysis. Trichuris grouped in a same clade with different hosts indicate the potential of cross infection between hosts. Based on COI, the adult Trichuris isolated from a Malaysian patient was most closely related to Trichuris isolated from Papio anubis (olive baboons) from the USA. The Trichuris isolated from the dog from Malaysia was genetically similar to a Trichuris species isolated from Macaca silenus (lion-tailed macaque) from Czech Republic. Both the human and dog isolated Trichuris grouped in clades with different hosts indicating the potential of cross infection between hosts. Specific PCR primers based on the partial COI of T. trichiura isolated from African green monkey and T. serrata were designed and successfully amplified using multiplex PCR of the pooled DNA samples. Our results suggest a complex parasite-host relationship, and support the theory of cross infection of Trichuris between humans and non-human primates as suggested in previous publications.

The tail of two models: Impact of circularity and biomass non-homogeneity on UV disinfection of wastewater flocs

The effects of floc structural characteristics, i.e. shape and dense biomass distribution, were evaluated on ultraviolet (UV) disinfection resistance, represented by the tailing level of the UV dose response curve (DRC). Ellipsoid-shaped flocs of similar volume and different projected circularities were constructed in-silico and a mathematical model was developed to compare their UV DRC tailing levels (indicative of UV-resistance). It was found that floc shape can significantly influence tailing level, and rounder flocs (i.e. flocs with higher circularity) were more UV-resistant. This result was confirmed experimentally by obtaining UV DRCs of two 75-90 μm floc populations with different percentages (20% vs. 30%) of flocs with circularities higher than 0.5. The population enriched in less circular flocs (i.e. 20% flocs with circularities >0.5) had a lower tailing level (at least by 1-log) compared to the other population. The second model was developed to describe variations in UV disinfection kinetics observed in flocs with transverse vs. radial biomass non-homogeneity, indicative of biofilm-originated vs. suspended flocs. The varied-density hemispheres model and shell-core model were developed to simulate transverse and radial non-homogeneity, respectively. The UV DRCs were mathematically constructed and biofilm-originated flocs showed higher UV resistance compared to suspended flocs. The calculated UV DRCs agreed well with the experimental data collected from activated sludge and trickling filter flocs (no fitting parameters were used). These findings provide useful information in terms of designing/modifying upstream processes for reducing UV disinfection energy demand.

Soil-Transmitted Helminths in Malaysia landscape: an aborigines study

Soil-transmitted helminths (STH) is a group of parasitic nematodes, including Trichuris trichiura, Ascaris lumbricoides, Ancylostoma duodenale and Necator americanus, which can cause gastrointestinal disorders in humans. STH is prevalent among neglected communities in both developing and developed countries. This present study aims to determine the current prevalence of STH infections in Aboriginal population after mass delivering of antihelminthic drugs was proposed by WHO in 2005 and a health education learning package (HELP) was initiated in Malaysia in 2012. A total of 235 human fecal samples were collected and a pre-tested questionnaire was given to gather information about the socio-demographic of the Aborigine communities living in Kedah and Selangor, Malaysia. The samples were screened by a direct-fecal smear and confirmed by formalin-ether sedimentation methods. From human faeces, 81.7% was found to be infected with one or more STH species. T. trichiura was the most commonly detected (76.6%), followed by hookworms (26.4%) and A. lumbricoides (19.1%). Triple infections were found in 6.4% of the studied population. Univariate analysis showed that individuals with age group, male, presence of indoor toilet, family size with <7 members and bad living habits (i.e., without antihelminthic drugs) were significantly associated with STH infections. The analysis further showed that walking barefoot was the significant contributing factor to hookworm infections. The high prevalence of human STH infections is alarming. Thus, the urgency in implementing health education related behavioral practice and hygiene to reduce disease burden in these rural communities are a crucial need.

Titiwangsa Lake a source of urban parasitic contamination

Urban recreational lake acts as a source of waterborne parasites contamination, as reported in 2013 in Petaling Jaya, Selangor, Malaysia. This scenario will lead to the transmission of waterborne diseases due to exposure of water-related activities by humans. This study was conducted to reveal the occurrence of common waterborne parasites in a urban lake (i.e. Titiwangsa Lake). The lake is situated in the city of Kuala Lumpur and is known to be overcrowded with vast activities participated by both local and tourist. Results of study showed the presence of Cryptosporidium, Giardia, free-living amoeba, and helminthlike ova from the lake.

TEST performance of a myositis panel in a clinical immunology laboratory in New South Wales, Australia

BACKGROUND

There is increasing recognition of a clinico-serological correlation between the idiopathic inflammatory myopathies and myositis-specific autoantibodies (MSA). We review the use of a line immunoassay-based myositis panel incorporating both MSA and myositis-associated autoantibodies (MAA) in a selected population of patients.

METHODS

A retrospective analysis of patients with myositis panel assays performed in 2013 were reviewed and compared against clinical diagnoses.

RESULTS

A total of 96 patient samples were evaluated, the clinical indications include 60 patients with suspected idiopathic inflammatory myositis (IIM), 24 patients with suspected interstitial lung disease (ILD) and 12 patients with suspected systemic autoimmune disease (SAD). In the myositis group, there were 21 patients diagnosed with IIM and 18 patients diagnosed with IIM had a positive myositis panel. Of the 39 patients without IIM, nine of these patients had a positive myositis panel. In the ILD group, 10 of 24 patients had a positive myositis panel; of these, two were diagnosed anti-synthetase syndrome (ASS) and five patients with ILD. In the suspected SAD group, three had positive myositis panel and all did not appear associated with their final diagnoses. In patients with a clinical diagnosis of IIM or ILD-associated SAD, four patients with anti-PL-12 were detected, three patients with anti-signal recognition protein, two patients with anti-Jo-1, and two patients with anti-Mi2.

CONCLUSIONS

The myositis panel is an objective investigative modality with a sensitivity of 80.00% and a specificity of 75.76% in a setting of high pretest clinical suspicion.

A preliminary screening of potentially antimalarial plants against Plasmodium falciparum in vitro

Plasmodium is a blood protozoan parasite that is responsible for malaria. To date, Plasmodium falciparum has shown multi-drug resistance, particularly in Thailand, Myanmar and Malaysia. The aim of the study is to screen the plant extracts that can effectively inhibit P. falciparum 3D7, a common lab strain malaria parasite. Nine plants were collected and processed through maceration using hexane, chloroform and ethanol, resulting in 24 crude plant extracts. Of these, extracts from Artabotrys crassifolius, Pericampylus glacus and Leuconotis eugeniifolia showed promising antiplasmodial activities at IC50 of 15.32 to 39.75 µg/mL in a modified schizont maturation assay. Further studies are warranted to explore its efficacies and lead compounds of these three plant extracts for the development of antiplasmodial drugs.

Molecular identification of Malaysian Chrysomya megacephala (Fabricius) and Chrysomya rufifacies (Macquart) using life stage specific mitochondrial DNA

DNA identification of blow fly species can be a very useful tool in forensic entomology. One of the potential benefits that mitochondrial DNA (mtDNA) has offered in the field of forensic entomology is species determination. Conventional identification methods have limitations for sibling and closely related species of blow fly and stage and quality of the specimen used. This could be overcome by DNA-based identification methods using mitochondrial DNA which does not demand intact or undamaged specimens. Mitochondrial DNA is usually isolated from whole blow fly and legs. Alternate sources for mitochondrial DNA isolation namely, egg, larva, puparium and empty puparium were explored in this study. The sequence of DNA obtained for each sample for every life cycle stage was 100% identical for a particular species, indicating that the egg, 1st instar, 2nd instar, 3rd instar, pupa, empty puparium and adult from the same species and obtained from same generation will exhibit similar DNA sequences. The present study also highlighted the usefulness of collecting all life cycle stages of blow fly during crime scene investigation with proper preservation and subsequent molecular analysis. Molecular identification provides a strong basis for species identification and will prove an invaluable contribution to forensic entomology as an investigative tool in Malaysia.

DNA typing of Calliphorids collected from human corpses in Malaysia

Estimation of post-mortem interval (PMI) is crucial for time of death determination. The advent of DNA-based identification techniques forensic entomology saw the beginning of a proliferation of molecular studies into forensically important Calliphoridae (Diptera). The use of DNA to characterise morphologically indistinguishable immature calliphorids was recognised as a valuable molecular tool with enormous practical utility. The local entomofauna in most cases is important for the examination of entomological evidences. The survey of the local entomofauna has become a fundamental first step in forensic entomological studies, because different geographical distributions, seasonal and environmental factors may influence the decomposition process and the occurrence of different insect species on corpses. In this study, calliphorids were collected from 13 human corpses recovered from indoors, outdoors and aquatic conditions during the post-mortem examination by pathologists from the government hospitals in Malaysia. Only two species, Chrysomya megacephala and Chrysomya rufifacies were recovered from human corpses. DNA sequencing was performed to study the mitochondrial encoded COI gene and to evaluate the suitability of the 1300 base pairs of COI fragments for identification of blow fly species collected from real crime scene. The COI gene from blow fly specimens were sequenced and deposited in GenBank to expand local databases. The sequenced COI gene was useful in identifying calliphorids retrieved from human corpses.

Apoptosis in Blastocystis spp. is related to subtype

Previous studies have shown that apoptosis-like features are observed in Blastocystis spp., an intestinal protozoan parasite, when exposed to the cytotoxic drug metronidazole (MTZ). This study reports that among the four subtypes of Blastocystis spp. investigated for rate of apoptosis when treated with MTZ, subtype 3 showed the highest significant increase after 72h of in vitro culture when treated with MTZ at 0.1mg/ml (79%; p<0.01) and 0.0001mg/ml (89%; p<0.001). The close correlation between viable cells and apoptotic cells for both dosages implies that the pathogenic potential of these isolates has been enhanced when treated with MTZ. This suggests that there is a mechanism in Blastocystis spp. that actually regulates the apoptotic process to produce higher number of viable cells when treated. Apoptosis may not just be programmed cell death but instead a mechanism to increase the number of viable cells to ensure survival during stressed conditions. The findings of the present study have an important contribution to influence chemotherapeutic approaches when developing drugs against the emerging Blastocystis spp. infections.

The flexor carpi radialisbrevis muscle - an anomaly in forearm musculature: a review article

The volar approach to the distal radius is an increasingly popular method of exposing fractures of the distal radius for purposes of reduction and internal fixation. We present five clinical cases and one cadaveric case of an incidental finding of an aberrant flexor of the forearm. A literature review undertaken showed few previous case reports of this relatively uncommon anatomic variant. The possibility of seeing the flexor carpi radialis brevis muscle during a volar approach to the distal radius should be made known to all orthopedic and hand surgeons.

Predominance of Blastocystis sp. subtype 4 in rural communities, Nepal

Blastocystis sp. is a common intestinal parasite. To date, there have been sporadic and scanty studies on Blastocystis sp. carried out in rural communities in Nepal. We surveyed the prevalence of Blastocystis sp. and its possible associated risk factors, and reported the predominant Blastocystis sp. subtype in two rural communities, Bolde Phediche and Bahunipati, in Nepal. Human faecal samples were collected from 241 participants, cultured using in vitro cultivation and examined for Blastocystis sp. The presence of Blastocystis sp. in faecal samples was further confirmed by polymerase chain reaction (PCR) and subsequently genotyped using subtype-specific sequence tagged site (STS) primers. There were 26.1% (63/241) of the participants that were infected by Blastocystis sp. We detected 84.1% (53/63) of Blastocystis sp. subtype 4 infections in these rural communities. The unusually high prevalence of Blastocystis sp. subtype 4 can be attributed to the rearing of family-owned animals in barns built close to their houses. Eighty one percent (51/63) of the Blastocystis sp. infected participants drank not boiled or unfiltered water. The present study revealed that Blastocystis sp. could pose a health concern to the communities and travellers to the hilly area in Nepal. Infection may be transmitted through human-to-human, zoonotic and waterborne transmissions. We provide recommendations to ensure good public health practices.

In vivo study of novel nanofibrous intra-luminal guidance channels to promote nerve regeneration

A novel nanofibrous construct for promoting peripheral nerve repair was fabricated and tested in a rat sciatic nerve defect model. The conduit is made out of bilayered nanofibrous membranes with the nanofibers longitudinally aligned in the lumen and randomly oriented on the outer surface. The intra-luminal guidance channel is made out of aligned nanofibrous yarns. In addition, biomolecules such as laminin and nerve growth factor were incorporated in the nanofibrous nerve construct to determine their efficacy in in vivo nerve regeneration. Muscle reinnervation, withdrawal reflex latency, histological, axon density and electrophysiology tests were carried out to compare the efficacy of nanofibrous constructs with an autograft. Our study showed mixed results when comparing the artificial constructs with an autograft. In some cases, the nanofibrous conduit with aligned nanofibrous yarn as an intra-luminal guidance channel performs better than the autograft in muscle reinnervation and withdrawal reflex latency tests. However, the axon density count is highest in the autograft at mid-graft. Functional recovery was improved with the use of the nerve construct which suggested that this nerve implant has the potential for clinical usage in reconstructing peripheral nerve defects.

Difficulties in recruiting older people in clinical trials: an examination of barriers and solutions

Limited information exists regarding optimal methods for the recruitment and retention of older people in clinical trials. The aim of this review is to identify common barriers to the recruitment of older people in clinical trials and to propose solutions to overcome these barriers. A review of literature was performed to identify common difficulties in recruiting older people. This in combination with our experience during recruitment for a randomized control trial, have highlighted numerous barriers. Population-specific recruitment strategies, simple informed-consent processes, and effective communication between the researcher and subject are effective strategies to overcome these barriers.

Genetic variability of Blastocystis sp. isolates obtained from cancer and HIV/AIDS patients

This represents the first study to determine the genetic diversity of Blastocystis sp. among cancer and HIV/AIDS patients. Forty Blastocystis sp. isolates obtained from 20 cancer and 20 HIV/AIDS patients were genotyped by PCR using seven pairs of known sequenced-tagged site primers. Out of the 40 isolates, 38 were identified as one of the known genotypes and two isolates were negative with all the STS primers. Blastocystis sp. subtype 3 which is reported to be associated with disease was found to be predominant among the study subjects.

Traumatic intracranial aneurysm in infancy

An anterior cerebral artery traumatic aneurysm in a 15-month-old infant is described. The diagnosis was confirmed by computed tomographic angiography. The patient recovered fully after successful clipping of the aneurysm. As the signs of traumatic intracranial aneurysm may be subtle especially in young children, a high degree of suspicion is essential in patients presenting with delayed neurological deterioration after head trauma.

Phenotypic and genotypic characterisation of Blastocystis hominis isolates implicates subtype 3 as a subtype with pathogenic potential

Despite frequent reports on the presence of Blastocystis hominis in human intestinal tract, its pathogenicity remains a matter of intense debate. These discrepancies may be due to the varying pathogenic potential or virulence of the isolates studied. The present study represents the first to investigate both phenotypic and genotypic characteristics of B. hominis obtained from symptomatic and asymptomatic individuals. Symptomatic isolates had a significantly greater size range and lower growth rate in Jones' medium than asymptomatic isolates. The parasite cells of symptomatic isolates exhibited rougher surface topography and greater binding affinity to Canavalia ensiformis (ConA) and Helix pomatia (HPA). The present study also identifies further phenotypic characteristics, which aided in differentiating the pathogenic forms from the non-pathogenic forms of B. hominis. Blastocystis subtype 3 was found to be correlated well with the disease.

Effect of basic military training on hearing in the Singapore Armed Forces

INTRODUCTION

In the military service, hearing is at risk through exposure to impulse noise from firing and detonations. This study aims at looking into the consequences of military training on hearing acuity, as it would be useful to confirm the effectiveness of the hearing conservation programme in the Singapore Armed Forces.

METHODS

A self-controlled study of 118 Singapore military conscripts was carried out, using questionnaires administered by trained personnel and pure tone audiometric assessments performed for both ears. The questionnaire and audiometry were done at the start of basic military training (BMT), with follow-up audiometry done at the end of BMT and one year into vocational military training (VT).

RESULTS

33 military conscripts were excluded subsequently in latter phases of the study. Of the 85 remaining conscripts, 16.5 percent of the study population were found to have abnormal audiograms at the start of BMT. At the end of the BMT phase, the percentage of enlistees with abnormal audiograms was 9.4 percent. By the end of one year of VT, the percentage of enlistees with abnormal audiograms was still 9.4 percent. Analysis of the differences in number of enlistees with hearing loss was done with the McNemar's test, and was found to be statistically insignificant (p-value equals 0.238).

CONCLUSION

The prevalence of 16.5 percent abnormal audiograms at the pre-BMT stage is probably related to unfamiliarity with the audiogram testing and/or "temporary threshold shift" effect. There was no significant difference in the number of enlistees with hearing loss upon enlistment and after one year of military training in this cohort of soldiers.

Evidence of plasmotomy in Blastocystis hominis

Blastocystis hominis has been regarded as an enigmatic parasite as many aspects of its basic biology remain uncertain. Many reproductive processes have been suggested for the organism; however, to date, only the binary fission has been proven. Plasmotomy is one of the modes of reproduction previously suggested to be seen in in vitro cultures. The present study provides trichrome and acridine orange staining evidence for the existence of nucleic acid suggestive of division of nucleus into multinucleate forms with the respective cytoplasm dividing giving rise to two or three progeny B. hominis. Transmission electron micrographs further confirmed that these daughter cells had respective surrounding surface coat, mitochondria, and vacuoles.

Giant cavernous hemangiomas: report of three cases

Giant cavernous hemangiomas occur very rarely, and little has been reported about their behavior. In this case report three cavernous hemangiomas with a diametric measure between 6 cm and 7 cm and distinct features will be described. A 36-year-old female patient presented with headache and nausea. A CT scan disclosed a large circumscribed tumor with strong contrast enhancement in the temporo-parieto-occipital region of the right cerebral hemisphere and extension into the right cerebellar hemisphere. A 35-year-old woman was admitted to our emergency ward with a generalized seizure and a dilated pupil. The CT scan showed an extensive left frontal lesion containing a substantial hyperintense part, suspicious for hemorrhage. A 3-year-old girl was admitted with generalized seizure and progressively declining consciousness. A large left frontotemporal paraventricular multi-cystic lesion was encountered on the CT scan. All three patients were operated on. Two recovered very well. In the case of the 3-year-old girl stable disease was reached. Giant cavernomas do not differ from average-sized cavernomas in clinical, surgical or histopathological presentation but may differ radiologically. However, the possible diagnosis of cavernoma can be overlooked, due to their size and possible differential diagnosis.