Subclinical joint inflammation in rheumatoid arthritis: comparing thermal and ultrasound imaging at the metacarpophalangeal joint

BACKGROUND

While ultrasound and MRI are both superior to clinical examination in the detection of joint inflammation, there is presently a lack of data whether thermography may be similarly useful in the assessment of joint inflammation in patients with RA. Our study aims to evaluate the use of thermography in detecting subclinical joint inflammation at clinically quiescent (non-tender and non-swollen) metacarpophalangeal joints (MCPJs) in patients with rheumatoid arthritis (RA). The outcomes from thermography in our study will be compared with ultrasonography (which is a more established imaging tool used for joint inflammation assessment in RA).

METHODS

The minimum (Tmin), average (Tavg) and maximum (Tmax) temperatures at the 10 MCPJs of each patient were summed to obtain the Total Tmin, Total Tavg and Total Tmax, respectively. Ultrasound grey-scale (GS) and power Doppler (PD) joint inflammation (scored semi-quantitatively, 0-3) at the 10 MCPJs were summed up to derive the respective TGS and TPD scores per patient. Pearson's correlation and simple linear regression were respectively used to assess correlation and characterize relationships between thermographic parameters (Total Tmin, Total Tavg and Total Tmax) and ultrasound imaging parameters (TGS, TPD and the number of joint(s) with PD ≥ 1 or GS ≥ 2).

RESULTS

In this cross-sectional study, 420 clinically non-swollen and non-tender MCPJs from 42 RA patients were examined. All thermographic parameters (Total Tmin, Total Tavg and Total Tmax) correlated significantly (P-values ranging from 0.001 to 0.0012) with TGS score (correlation coefficient ranging from 0.421 to 0.430), TPD score (correlation coefficient ranging from 0.383 to 0.424), and the number of joint(s) with PD ≥ 1 or GS ≥ 2 (correlation coefficient ranging from 0.447 to 0.465). Similarly, simple linear regression demonstrated a statistically significant relationship (P-values ranging from 0.001 to 0.005) between all thermographic parameters (Total Tmin, Total Tavg and Total Tmax) and ultrasound imaging parameters (TPD and TGS).

CONCLUSION

For the first time, thermographic temperatures were shown to correlate with ultrasound-detected joint inflammation at clinically quiescent MCPJs. The use of thermography in the detection of subclinical joint inflammation in RA appears promising and warrants further investigation.

Thermography at the Elbow Among Patients with Rheumatoid Arthritis: A Comparison with Ultrasound-Detected Joint Inflammation Findings

INTRODUCTION

There is a lack of data on the use of thermography for elbow joint inflammation assessment among patients with rheumatoid arthritis (RA). Hence, we aimed to compare thermography with ultrasonography (a more established imaging modality for joint inflammation assessment) in the assessment of inflammation in the elbows of patients with RA.

METHODS

Standardised minimum (Tmin), maximum (Tmax) and average (Tavg) temperatures at each elbow (medial, lateral, posterior and anterior aspects) were summed to obtain the thermographic parameters MIN, MAX and AVG, respectively. Ultrasound parameters of elbow joint inflammation included total greyscale (TGS) and total power Doppler (TPD) scores. Pearson's correlation coefficient was utilized for correlation analysis between parameters. The relationship between parameters was characterized using simple linear regression.

RESULTS

Sixty elbows were evaluated from 30 patients with RA in this cross-sectional study. Thermographic parameters (MIN, MAX and AVG) showed significant correlation (P < 0.05) with (1) TPD scores at both elbows (correlation coefficient ranging 0.40 to 0.55) and (2) TGS scores at the right elbow (correlation coefficient ranging 0.39 to 0.42). A statistically significant relationship (P values ranging from 0.002 to 0.033) between parameters was demonstrable as follows: (1) MIN, MAX and AVG versus TPD scores (bilateral elbows) and (2) MIN, MAX and AVG versus TGS scores (right elbow).

CONCLUSION

Thermographic temperatures have been demonstrated to correlate with ultrasound-detected joint inflammation at the elbow in patients with RA. The association is more consistently observed with ultrasound PD joint inflammation than its GS counterpart.

Detection of Atrial Fibrillation After Ischemic Stroke with an Insertable Cardiac Monitor: A Systematic Review and Individual Patient Data Meta-Analysis of Randomised Clinical Trials

OBJECTIVE

In ischemic stroke patients, we compared the use of insertable cardiac monitor (ICM) versus non-ICM methods of cardiac monitoring on the incidence of atrial fibrillation (AF) detection and other clinical outcomes.

BACKGROUND

Current guidelines recommend the routine use of 12-lead electrocardiography or Holter monitoring for AF detection after ischemic stroke. Recent randomised controlled trials have investigated the impact of ICM versus non-ICM methods of cardiac monitoring for AF detection in this population. However, precise recommendations for monitoring post-stroke AF are lacking; including the optimal timing, duration, and method of electrocardiography monitoring.

METHODS

A systematic search was conducted on Embase and PubMed from database inception until 27 October 2022 to include randomised controlled trials that compared ICM with non-ICM methods of cardiac monitoring for post-stroke AF detection. This yielded 3 randomised controlled trials with a combined cohort of 1231 patients with a recent ischemic stroke. Individual patient data (IPD) was then reconstructed from Kaplan-Meier curves and analysed using the shared-frailty Cox model. An aggregate data meta-analysis was conducted for 1231 patients across all 3 studies for outcomes that could not be reconstructed using IPD.

RESULTS

One-stage meta-analysis demonstrated an increase in the hazard ratio (HR 6.01, 95% CI 3.40-10.60; p<0.001) of AF detection in patients undergoing monitoring via ICM compared to standard care. Aggregate data meta analysis revealed a significant increase in initiation of anticoagulation (OR 3.09, 95% CI 2.05 - 4.66; p<0.00001) in the ICM group. However, no significant differences in the incidence of recurrent ischemic stroke, transient ischemic attack or death were found.

CONCLUSIONS

In this meta-analysis, we found that the use of ICM increased the detection rate of post-stroke AF and the rate of anticoagulation initiation. However, this did not translate into a reduced incidence of recurrent ischemic stroke.

Receiver operating characteristic analysis using a novel combined thermal and ultrasound imaging for assessment of disease activity in rheumatoid arthritis

We aim to determine whether combined thermal and ultrasound (CTUS) imaging can identify rheumatoid arthritis (RA) patients with at least moderate disease activity (DAS28 > 3.2). Temperature differences of maximum (T_max), average (T_avg) and minimum (T_min) temperatures from a control temperature at 22 joints (bilateral hands) were summed up to derive the respective MAX, AVG and MIN per patient. MAX (PD), AVG (PD) and MIN (PD) are CTUS results derived by multiplying MAX, AVG and MIN by a factor of 2 when a patient's total ultrasound power Doppler (PD) joint inflammation score > median score, which otherwise remained unchanged. Receiver operating characteristic (ROC) analysis was used to determine whether CTUS imaging can identify patients with DAS28 > 3.2. In this cross-sectional study, 814 joints were imaged among 37 RA patients (mean disease duration, 31 months). CTUS (but not single modality) imaging parameters were all significantly greater comparing patients with DAS28 > 3.2 versus those with DAS28 ≤ 3.2 (all P < 0.01). Area under the ROC curves (AUCs) using cut-off levels of ≥ 94.5, ≥ 64.6 and ≥ 42.3 in identifying patients with DAS28 > 3.2 were 0.73 , 0.76 and 0.76 for MAX (PD), AVG (PD) and MIN (PD), respectively (with sensitivity ranging from 58 to 61% and specificity all 100%). The use of CTUS in detecting a greater severity of joint inflammation among patients with at least moderate disease activity (DAS28 > 3.2) appears promising and will require further validation in independent RA cohorts.

A musculoskeletal ultrasound program as an intervention to improve disease modifying anti-rheumatic drugs adherence in rheumatoid arthritis: a randomized controlled trial

Objectives: To evaluate the effect of a musculoskeletal ultrasound programme (MUSP) applying real-time ultrasonography with reinforcement of findings by a rheumatologist on improving disease-modifying anti-rheumatic drugs (DMARDs) adherence in rheumatoid arthritis (RA).Method: Eligible RA patients with low adherence score (< 6) on the 8-item Morisky Medication Adherence Scale (MMAS-8) were randomized to either an intervention group (receiving MUSP at baseline) or a control group (no MUSP), and followed up for 6 months. Adherence measures (patient-reported and pharmacy dispensing records) and clinical efficacy data were collected. The MUSP's feasibility and acceptability were assessed.Results: Among 132 recruited RA patients, six without baseline visits were excluded; therefore, 126 patients were analysed (62 intervention and 64 control). The primary outcome (proportion of patients with 1 month MMAS-8 score < 6) was significantly smaller (p = 0.019) in the intervention (35.48%) than the control group (56.25%). However, 3 and 6 month adherence and clinical efficacy outcomes were not significantly different between the two groups (all p > 0.05). All 62 patients completed the MUSP (mean time taken, 9.2 min), with the majority reporting moderately/very much improved understanding of their joint condition (71%) and the importance of regularly taking their RA medication(s) (79%). Most patients (90.3%) would recommend the MUSP to another RA patient.Conclusions: The MUSP improved RA patients' DMARDs adherence in the short term and was feasible and well accepted by patients. Future studies could evaluate whether repeated feedback using MUSP could help to sustain the improvement in DMARD adherence in RA patients, and whether this may be clinically impactful and cost-effective.

A novel use of combined thermal and ultrasound imaging in detecting joint inflammation in rheumatoid arthritis

PURPOSE

To evaluate the use of combined thermal and ultrasound imaging to assess joint inflammation in rheumatoid arthritis (RA).

METHOD

22-joint (bilateral hands) thermography and ultrasonography were performed. For each patient, the MAX, MIN and AVG represent the sum of the temperature differences with a control temperature, for the respective maximum (Tmax), minimum (Tmin) and average (Tavg) temperatures at the joints. MAX (PD), MIN (PD) and AVG (PD) represent the results of combined thermal imaging with a patient's total ultrasound power Doppler (PD) joint inflammation score (Total PD) (when Total PD > median score, MAX, MIN and AVG was multiplied by a factor of 2, otherwise MAX (PD), MIN (PD) and AVG (PD) remained the same as the MAX, MIN and AVG). Pearson correlation and linear regression were used to assess correlation and characterize relationships of imaging parameters with the 28-joint disease activity score (DAS28).

RESULTS

In this cross-sectional study, 814 joints were examined in 37 adult RA patients (75.7 % female, 75.7 % Chinese; mean DAS28, 4.43). Among the imaging parameters, only MAX (PD) and AVG (PD) correlated significantly with DAS28 (correlation coefficient (95 % CI): MAX (PD), 0.393 (0.079, 0.636), P = 0.016; AVG (PD): 0.376 (0.060, 0.624), P = 0.022). Similarly, only MAX (PD) and AVG (PD) demonstrated a statistically significant relationship with DAS28 (regression coefficient (95 % CI): MAX (PD), 0.009 (0.002, 0.015), P = 0.016; AVG (PD), 0.011 (0.002, 0.020), P = 0.022).

CONCLUSIONS

Novel use of combined thermal and ultrasound imaging in RA shows superiority to either imaging alone in terms of correlation with DAS28.

Joint damage in rheumatoid arthritis: Lessons learned from an extended 36-joint ultrasonography and 28-joint Disease Activity Score assessments

AIM

To study joint damage severity in rheumatoid arthritis (RA) patients classified using ultrasound power Doppler (PD) and gray-scale (GS) joint inflammation outcomes and the 28-joint Disease Activity Score (DAS28).

METHOD

Ultrasound erosion scores were compared between (a) patients in group 1 (PD positive and GS ≥ median score), group 2 (PD negative and GS ≥ median score) and group 3 (PD positive and GS < median score) vs group 4 (PD negative and GS < median score) and (b) patients with high, moderate and low DAS28 scores vs those in DAS28 remission. Comparative analyses were performed using the 2-sample Student's t test.

RESULTS

There were 1080 joints and 1800 joint recesses from 36 joints scanned in 30 RA adult patients (mean DAS28, 3.58; mean disease duration, 70.3 months) in this cross-sectional study. The mean and 95% CI ultrasound erosion scores were significantly higher (P = .026) for groups 1 (9.75, 6.69-12.81) vs 4 (3.4, 1.11-5.69) with a difference (95% CI) of 6.35 (0.78-11.83), but not significantly different (P values all > .05) for (a) groups 2 and 3 vs 4 and (b) patients with high, moderate and low DAS28 scores vs those in DAS28 remission.

CONCLUSION

Severity of ultrasound-detected bone erosions was significantly greater when both positive PD and a greater degree of GS joint inflammation were present in RA. This association was not observed when either component was absent. Single time point ultrasound joint inflammation assessment - and not DAS28 - is reflective of joint damage severity in RA patients.

The Role of Musculoskeletal Ultrasound Imaging in Rheumatoid Arthritis

Musculoskeletal ultrasound (MSUS) is gaining popularity among rheumatologists, especially in the context of rheumatoid arthritis (RA) joint assessment, as it is a non-invasive, radiation-free imaging modality that is relatively easy to set up in a clinic setting. Although ultrasonography (US) is often regarded as being operator dependent with associated reproducibility issues, the use of consensus-based scoring system along with standardized definition of joint inflammation in RA has been shown to improve its performance/reliability as an outcome measurement tool. Through this review article, we have (i) gone through the principle US findings in RA joint assessment, (ii) discussed various scoring systems for evaluation of US joint pathologies, (iii) described the literature in the use of US in areas of RA diagnosis and disease prognostication and (iv) examined the findings of recent major randomized controlled trials incorporating US as monitoring tools to help target treatment in RA. By doing so, we hope to provide clinicians with an insight into the role of musculoskeletal US imaging in areas of RA diagnosis, prognosis and disease monitoring.

Extended 36-joint sonographic examination: What it reveals about bone erosions in patients with rheumatoid arthritis

PURPOSE

To identify joints commonly exhibiting bone erosions using an extended 36-joint sonographic (US) examination in patients with rheumatoid arthritis (RA) and to study bone erosion in relation to US-detected joint inflammation.

METHODS

In this cross-sectional study, power Doppler (PD) and gray-scale (GS) joint inflammation scores (semi-quantitative [0-3] grading) at each joint recess were summed to obtain a combined US score (CUS). Bone erosion was scored as present/absent. Generalized Estimating Equations were used to compare mean US scores between joint recesses with and without bone erosion.

RESULTS

Bone erosion was found in 144/1080 (13.3%) joints and 189/1800 (10.5%) joint recesses in 30 RA patients. The five joints most frequently associated with bone erosion were: wrist, n = 49/144 (34.0%); first MTPJ, n = 19/144 (13.2%); thumb IPJ, n = 13/144 (9.0%); second MCPJ, n = 11/144 (7.6%); and third MCPJ, n = 11/144 (7.6%). Mean (95% CI) US scores for joint recesses with and without bone erosion were PD: 0.36 (0.21, 0.50) vs 0.01 (0.00, 0.02); GS: 1.77 (1.54, 2.00) vs 0.47 (0.40, 0.55); and CUS: 2.13 (1.78, 2.47) vs 0.49 (0.41, 0.57) (all differences significant at P < .001).

CONCLUSION

The five joints most frequently showing bone erosion were identified. Joint recesses with bone erosion are more likely to exhibit greater PD and GS joint inflammation severity.

Back to the basics: Understanding joint swelling and tenderness at the wrist in rheumatoid arthritis through the use of ultrasonography

AIM

To compare ultrasound-detected inflammation with clinical manifestations at the wrist in rheumatoid arthritis (RA).

METHOD

Wrists assessed serially by assessors blinded to ultrasound findings were categorized into 4 groups: 1 = S0T0 (not swollen; not tender); 2 = S0T1 (not swollen; tender); 3 = S1T0 (swollen; not tender); 4 = S1T1 (swollen; tender). Ultrasound synovitis and tenosynovitis were graded semi-quantitatively (0-3) and dichotomously (0 or 1), respectively. The (a) power Doppler (PD), gray-scale (GS) and combined (PD + GS) ultrasound (CUS) scores and (b) their positivity (score > 0) were analyzed using a general linear repeated measures mixed model (a) assuming Gaussian errors and (b) with binary distribution and logit link, respectively. Pairwise comparisons among wrist groups were performed within context of the models.

RESULTS

In 122 wrist assessments (baseline = 64; 3 months = 58) from 32 treated RA patients (87.5% female; mean disease duration 42.8 months), significant differences among groups for (a) scores were: 4 vs 1 (PD, P = 0.0031; GS, P = 0.0159; CUS, P = 0.0045), 4 vs 2 (PD, P = 0.0176; GS, P = 0.0160; CUS, P = 0.0074), and 4 vs 3 (CUS, P = 0.0374); and (b) positivity were: 4 vs 1 (PD, P = 0.0007), 4 vs 2 (PD, P = 0.0234), and 3 vs 1 (PD, P = 0.0202). No significant differences in results were found for groups 2 vs 1. No significant effects were attributable to differences in wrist side or follow-up visit.

CONCLUSION

Ultrasound detected substantial inflammation when wrist joint swelling and tenderness are both present. Joint swelling without tenderness is associated with significantly more frequent PD detection. Without swelling, joint tenderness is not associated with a significantly greater degree of ultrasound-detected inflammation.

Greater rheumatoid arthritis joint improvement with more subjects achieving response across improvement categories using novel versus existing ultrasound methods

We compared the change in joint inflammation and the proportion of subjects achieving threshold levels of improvement using the existing methods employing ultrasonography on pre-determined joint sites versus novel methods. These novel methods select the most affected joints based on (i) ultrasonography-the Individualized-Ultrasound (IUS) method, or (ii) ultrasonography and clinical joint assessment-the individualized-Composite-Ultrasound (ICUS) method. Mean 3-month change in total inflammation score (ΔTIS) and 95% CI was computed for each method on 24 RA subjects initiated or escalated on treatment. Individual improvement in TIS per subject, calculated as the 3-month ΔTIS divided by the maximum possible TIS score expressed as a percentage, was used to obtain the proportion of subjects achieving response across improvement categories. Mean 3-month ΔTIS was significantly greater (p values ranging from 0.0003 to 0.0026) for novel versus existing methods using 12- and 7-joint approaches. Using 12-joint approach, percentages of subjects in improvement categories ≥5%, ≥10%, ≥15% and ≥20% were, respectively, 50, 37.5, 12.5 and 8.3% for IUS; 58.3, 37.5, 12.5 and 8.3% for ICUS; and 16.7, 0, 0 and 0% for the existing method. Using 7-joint approach, the respective category percentages were 62.5, 37.5, 25 and 12.5% for IUS; 62.5, 41.7, 16.7 and 8.3% for ICUS; and 12.5, 4.2, 4.2 and 0% for the existing method. Novel ultrasound methods are more likely to detect improvement in joint inflammation, with more subjects achieving response across improvement categories, thereby representing a substantial advantage over the existing methods. However, this requires confirmation in larger RA cohorts.

Novel joint selection methods can reduce sample size for rheumatoid arthritis clinical trials with ultrasound endpoints

OBJECTIVES

To determine whether novel methods of selecting joints through (i) ultrasonography (individualized-ultrasound [IUS] method), or (ii) ultrasonography and clinical examination (individualized-composite-ultrasound [ICUS] method) translate into smaller rheumatoid arthritis (RA) clinical trial sample sizes when compared to existing methods utilizing predetermined joint sites for ultrasonography.

METHODS

Cohen's effect size (ES) was estimated (ES^) and a 95% CI (ES^L, ES^U) calculated on a mean change in 3-month total inflammatory score for each method. Corresponding 95% CIs [nL(ES^U), nU(ES^L)] were obtained on a post hoc sample size reflecting the uncertainty in ES^. Sample size calculations were based on a one-sample t-test as the patient numbers needed to provide 80% power at α = 0.05 to reject a null hypothesis H₀ : ES = 0 versus alternative hypotheses H₁ : ES = ES^, ES = ES^L and ES = ES^U. We aimed to provide point and interval estimates on projected sample sizes for future studies reflecting the uncertainty in our study ES^S.

RESULTS

Twenty-four treated RA patients were followed up for 3 months. Utilizing the 12-joint approach and existing methods, the post hoc sample size (95% CI) was 22 (10-245). Corresponding sample sizes using ICUS and IUS were 11 (7-40) and 11 (6-38), respectively. Utilizing a seven-joint approach, the corresponding sample sizes using ICUS and IUS methods were nine (6-24) and 11 (6-35), respectively.

CONCLUSIONS

Our pilot study suggests that sample size for RA clinical trials with ultrasound endpoints may be reduced using the novel methods, providing justification for larger studies to confirm these observations.

Dichotomous versus semi-quantitative scoring of ultrasound joint inflammation in rheumatoid arthritis using novel individualized joint selection methods

The aim of the study is to compare the responsiveness of two joint inflammation scoring systems (dichotomous scoring (DS) versus semi-quantitative scoring (SQS)) using novel individualized ultrasound joint selection methods and existing ultrasound joint selection methods. Responsiveness measured by the standardized response means (SRMs) using the DS and the SQS system (for both the novel and existing ultrasound joint selection methods) was derived using the baseline and the 3-month total inflammatory scores from 20 rheumatoid arthritis patients. The relative SRM gain ratios (SRM-Gains) for both scoring system (DS and SQS) comparing the novel to the existing methods were computed. Both scoring systems (DS and SQS) demonstrated substantial SRM-Gains (ranged from 3.31 to 5.67 for the DS system and ranged from 1.82 to 3.26 for the SQS system). The SRMs using the novel methods ranged from 0.94 to 1.36 for the DS system and ranged from 0.89 to 1.11 for the SQS system. The SRMs using the existing methods ranged from 0.24 to 0.32 for the DS system and ranged from 0.34 to 0.49 for the SQS system. The DS system appears to achieve high responsiveness comparable to SQS for the novel individualized ultrasound joint selection methods.

Utility of ultrasonography in guiding modification of disease modifying anti-rheumatic drugs and steroid therapy for inflammatory arthritis in routine clinical practice

OBJECTIVE

To determine the utility of ultrasonography in guiding modification of disease-modifying anti-rheumatic drug (DMARD) and steroid therapy for inflammatory arthritis (IA) in routine clinical practice.

METHODS

In this retrospective study, we analyzed DMARD and steroid use in IA patients referred to a rheumatologist-led ultrasound clinic. Power Doppler (PD) vascularity and greyscale (GS) synovial hypertrophy joint findings were categorized as positive/negative for each patient. The erythrocyte sedimentation rate (ESR) was used as a measure of disease activity.

RESULTS

We assessed single visit data for 46 adult IA patients: 67.4% (n = 31) rheumatoid arthritis (RA), 15.2% (n = 7) psoriatic arthritis, 10.9% (n = 5) spondyloarthritis, and 6.5% (n = 3) undifferentiated IA. The mean ESR was 28.8 mm/h. Thirty-seven patients with both GS and PD ultrasound results were subsequently analyzed. All patients (n = 10) escalated and/or initiated on DMARD and 9/10 patients escalated or initiated on steroids were PD and GS positive. Six of seven patients with dose reduction and/or cessation of DMARDs and five of seven patients with dose reduction or cessation of steroids were PD negative. Of six patients who were GS positive and PD negative, three had dose reduction and/or cessation of DMARDs, while four had dose reduction of steroids; none of the six patients had DMARD/steroid escalation.

CONCLUSION

By clarifying joint inflammation in an IA cohort with overall low ESR, ultrasonography of physician-selected joints can improve clinical assessment, resulting in treatment modification. Positive PD findings were particularly influential, while the clinical significance of GS positivity alone requires further investigation.

Novel Ultrasound Joint Selection Methods Using a Reduced Joint Number Demonstrate Inflammatory Improvement when Compared to Existing Methods and Disease Activity Score at 28 Joints

OBJECTIVE

A pilot study testing novel ultrasound (US) joint-selection methods in rheumatoid arthritis.

METHODS

Responsiveness of novel [individualized US (IUS) and individualized composite US (ICUS)] methods were compared with existing US methods and the Disease Activity Score at 28 joints (DAS28) for 12 patients followed for 3 months. IUS selected up to 7 and 12 most ultrasonographically inflamed joints, while ICUS additionally incorporated clinically symptomatic joints.

RESULTS

The existing, IUS, and ICUS methods' standardized response means were -0.39, -1.08, and -1.11, respectively, for 7 joints; -0.49, -1.00, and -1.16, respectively, for 12 joints; and -0.94 for DAS28.

CONCLUSION

Novel methods effectively demonstrate inflammatory improvement when compared with existing methods and DAS28.

The open retrograde approach as an alternative for failed percutaneous access for difficult below the knee chronic total occlusions-A case series

Retrograde puncture via patent pedal vessels can be attempted in failed antegrade approach for infrapopliteal long chronic total occlusion. However in cases where the pedal vessels are unable to be visualized via duplex ultrasonography or fluoroscopy an open approach offers an additional option to a vascular surgeon for successful recanalization. Our case report highlights 3 cases where successful hybrid open retrograde approach was able to achieve recanalization of long chronic total occlusion.

Presentation of cases

The three cases in our series presented with critical limb ischaemia. All three cases had undergone duplex imaging of the affected arterial system. As the antegrade approach to cross the lesion failed a retrograde approach was attempted in all 3 cases. However when the usual modality of retrograde puncture via the use of ultrasound or fluoroscopy failed we proceeded with an open approach.

Discussion

Retrograde approach usually offers a better chance of successfully crossing a chronic total occlusion lesion. However puncturing a distal vessel successfully and traversing a catheter or guidewire across proves to be a challenge. An open approach offers an additional pathway for puncturing the target vessel when duplex imaging or fluoroscopic guidance fails.

Conclusion

Open approach is usually attempted as a last resort by many endovascular surgeons. However procedural time, contrast and radiation usage could have been cut short in cases where the distal target vessels pose a technical challenge for approach via a percutaneous method.

Ex vivo-expanded but not in vitro-induced human regulatory T cells are candidates for cell therapy in autoimmune diseases thanks to stable demethylation of the FOXP3 regulatory T cell-specific demethylated region

Regulatory T cell (Treg) therapy is a promising approach for transplant rejection and severe autoimmunity. Unfortunately, clinically meaningful Treg numbers can be obtained only upon in vitro culture. Functional stability of human expanded (e)Tregs and induced (i)Tregs has not been thoroughly addressed for all proposed protocols, hindering clinical translation. We undertook a systematic comparison of eTregs and iTregs to recommend the most suitable for clinical implementation, and then tested their effectiveness and feasibility in rheumatoid arthritis (RA). Regardless of the treatment, iTregs acquired suppressive function and FOXP3 expression, but lost them upon secondary restimulation in the absence of differentiation factors, which mimics in vivo reactivation. In contrast, eTregs expanded in the presence of rapamycin (rapa) retained their regulatory properties and FOXP3 demethylation upon restimulation with no stabilizing agent. FOXP3 demethylation predicted Treg functional stability upon secondary TCR engagement. Rapa eTregs suppressed conventional T cell proliferation via both surface (CTLA-4) and secreted (IL-10, TGF-β, and IL-35) mediators, similarly to ex vivo Tregs. Importantly, Treg expansion with rapa from RA patients produced functionally stable Tregs with yields comparable to healthy donors. Moreover, rapa eTregs from RA patients were resistant to suppression reversal by the proinflammatory cytokine TNF-α, and were more efficient in suppressing synovial conventional T cell proliferation compared with their ex vivo counterparts, suggesting that rapa improves both Treg function and stability. In conclusion, our data indicate Treg expansion with rapa as the protocol of choice for clinical application in rheumatological settings, with assessment of FOXP3 demethylation as a necessary quality control step.

Ultrasound versus high field magnetic resonance imaging in rheumatoid arthritis

Over the past decade there have been significant advances in the field of musculoskeletal imaging, especially in the application of ultrasound (US) and magnetic resonance imaging (MRI) to the management of rheumatoid arthritis (RA). Both modalities offer significant advantages over the previous standards of clinical examination and radiography, and allow direct visualisation of both joint inflammation and structural damage. Although measuring similar pathology, each of these imaging tools has its own benefits and limitations; understanding these will help researchers and clinicians to determine the appropriate role for these tools in RA joint assessment. This review article seeks to compare the usefulness of US and MRI in RA diagnosis, prognosis and outcome assessment.

Achieving consensus in ultrasonography synovitis scoring in rheumatoid arthritis

OBJECTIVE

Ultrasonography is sensitive for synovitis detection but interobserver variation in both acquisition and image interpretation is still a concern. The objective was to assess if a short collegiate consensus would improve inter-observer reliability in scoring of synovitis.

METHODS

Eight rheumatologists (Singapore) participated in a 1-day consensus meeting divided into: (i) still-image interpretation and consensus followed by; (ii) image acquisition and interpretation, according to definitions and synovitis scoring rules endorsed by Outcome Measures in Rheumatology (OMERACT) and TUI (Targeted Ultrasound Initiative). Interobserver reliability of semiquantitative scoring in B-mode, Power Doppler (PDUS) and European League Against Rheumatism (EULAR)-OMERACT PDUS composite score was assessed by intraclass correlation co-efficient (ICC). Agreement at the joint region level was calculated using prevalence-adjusted-biased-adjusted-kappa (PABAK).

RESULTS

For B-mode still images, ICC was good at 0.75 (95% CI 0.66-0.82) while for PDUS images this was excellent at ICC = 0.88 (95% CI 0.83-0.92) with ICC improving by 12% for B-mode and 13% for PDUS respectively. During image acquisition and interpretation, B-mode scoring showed ICC = 0.75 (95% CI 0.66-0.84) while for PDUS the ICC was lower at 0.59 (95% CI 0.48-0.72). The ICC for OMERACT PDUS composite synovitis scoring was good at 0.77 (95% CI 0.68-0.85). At the joint level, agreement varied with PABAK being excellent in the small joints of the hands but poor to fair in the wrists, elbows, ankles and metatarsophalangeal joints, and no agreement at the knees (PABAK range -0.34 to 0.85).

CONCLUSION

A consensus meeting was useful in improving interobserver variation in US synovitis scoring of still images, but image acquisition and interpretation especially in non-hand joints require further standardization.

Imaging tools in rheumatoid arthritis: ultrasound vs magnetic resonance imaging

As modern imaging tools such as US and MRI become increasingly available, rheumatologists now have access to highly sensitive measures to assist in the evaluation of both the inflammatory and structural damage components underlying various arthritides over the disease duration. Both US and MRI have associated strengths and weaknesses, and at times they can provide complementary information. This review compares the performance of US vs MRI as diagnostic, prognostic and monitoring tools for RA, and to provide insights into which modality can provide the optimal information for a desired outcome in a given clinical trial or practice situation.

Disease patterns of rheumatology outpatients seen in a tertiary hospital serving a multi-ethnic, urban Asian population in Singapore

AIMS

To describe the spectrum of diseases seen in an outpatient setting in the Singapore General Hospital, the largest tertiary referral centre in Singapore.

METHODS

In this cross-sectional study, medical records of patients scheduled for an appointment at the rheumatology specialist outpatient clinics over a 4-month period (10 August 2010-31 December 2010) were reviewed. Primary diagnoses documented by the attending physician at the latest visit were recorded.

RESULTS

Among 4180 patients (29.5% male; mean [SD] age: 53.5 [15.1] years; 77.0% Chinese, 8.0% Malay, 8.8% Indian and 6.2% others), the spectrum of diseases seen was as follows [disease - definite n (%), probable n (%)]: Arthritis: rheumatoid arthritis - 958 (22.9%), 68 (1.6%); osteoarthritis - 452 (10.8%), 39 (0.9%); crystal arthritis - 417 (10.0%), 18 (0.4%); spondyloarthritis - 227 (5.4%), 61 (1.5%); psoriatic arthritis - 158 (3.8%), 9 (0.2%); other inflammatory arthritis - 153 (3.7%), 94 (2.2%); Connective tissues diseases: systemic lupus erythematosus - 412 (9.9%), 26 (0.6%); vasculitis - 105 (2.5%), 22 (0.5%); Sjögren's syndrome - 81 (1.9%), 32 (0.8%); overlap syndromes - 73 (1.8%); scleroderma - 50 (1.2%), 4 (0.1%); undifferentiated connective tissue diseases - 45 (1.1%), 106 (2.5%); myositis - 41 (1.0%), 12 (0.3%); antiphospholipid syndrome - 22 (0.5%), 7 (0.2%); polymyalgia rheumatica - 16 (0.4%); Others: soft tissue rheumatism - 155 (3.7%); osteoporosis - 61 (1.5%); other non-rheumatologic conditions - 189 (4.5%); other rheumatologic conditions - 67 (1.6%).

CONCLUSION

Rheumatoid arthritis, osteoarthritis and crystal arthritis were the three most common rheumatological diseases seen in a tertiary referral centre serving a multi-ethnic urban Asian population in Singapore.

Imaging in rheumatoid arthritis

The optimal management of rheumatoid arthritis (RA) requires tools that allow early and accurate disease diagnosis, prediction of poor prognosis and responsive monitoring of therapeutic outcomes. Conventional radiography has been widely used in both clinical and research settings to assess RA joint damage due to its feasibility, but it has limitations in early disease detection and difficulty distinguishing between active treatments in modern trials. Imaging modalities such as magnetic resonance imaging (MRI) and ultrasound (US) have the advantage of detecting both joint inflammation and damage and hence they can provide additional and unique information. This can be especially useful in the context of early and/or undifferentiated joint disease when detection of soft tissue and bone marrow abnormalities is desirable. This review focusses on the recent literature concerning modern imaging, and provides clinicians with an insight into the role of imaging in modern RA diagnosis, prognosis and monitoring.

Use of radiosynovectomy in recurrent warfarin-related haemarthrosis in degenerative arthritis

Radiosynovectomy is a local and minimally invasive radiotherapy for treating various chronic inflammatory arthritis such as rheumatoid arthritis, osteoarthritis and haemophilic arthropathy. In haemophilic arthropathy, it reduces the frequency of haemarthrosis and delays the development of severe joint destruction, which ultimately requires surgical intervention. Its role in warfarin-related haemarthrosis is less clear. Haemarthrosis is an uncommon complication of warfarin use, and anticoagulation may need to be discontinued. We describe yttrium-90 radiosynovectomy use in a 74-year-old man with underlying ischaemic heart disease, atrial fibrillation, previous embolic stroke and recurrent haemarthrosis of an osteoarthritic right knee. Anticoagulation was vital and could not be permanently stopped. Due to continuing anticoagulation, he had multiple hospitalisations with recurrent right knee haemarthrosis. Intraarticular right knee yttrium-90 citrate colloid injection led to a cessation of haemarthrosis for eight months. We examined the available literature for the role of radiosynovectomy in such circumstances.

Pulse electroplating of copper film: a study of process and microstructure

Copper films with high density of twin boundaries are known for high mechanical strength with little tradeoff in electrical conductivity. To achieve such a high density, twin lamellae and spacing will be on the nanoscale. In the current study, 10 microm copper films were prepared by pulse electrodeposition with different applied pulse peak current densities and pulse on-times. It was found that the deposits microstructure was dependent on the parameters of pulse plating. Higher energy pulses caused stronger self-annealing effect on grain recrystallization and growth, thus leading to enhanced fiber textures, while lower energy pulses gave rise to more random microstructure in the deposits and rougher surface topography. However in the extremes of pulse currents we applied, the twin densities were not as high as those resulted from the medium or relatively high pulse currents. The highest amount of nanoscale twinning was found to form from a proper degree of self-annealing induced grain structure evolution. The driving force behind the self-annealing is discussed.

Survival among Chinese women with lung cancer in Singapore: a comparison by stage, histology and smoking status

Lung cancer generally carries a poor prognosis and the determinants of survival have been of interest. However, survival estimates in Asian populations are scarce. This study describes survival rates and their determinants in Singapore Chinese women, a primarily non-smoking population. Three hundred and twenty-six Chinese women, diagnosed with primary lung carcinoma in three major hospitals in Singapore between April 1996 and December 1998, were followed up till 31 December 2000. The Kaplan-Meier method was used for survival analysis. Two hundred and eighty (85.7%) died from the disease during follow-up. The median survival time was 0.7 years and the three-year survival was 15.8%. These survival rates are similar to those of Western populations, and they provide a basis for examining trends over time. Age at diagnosis was an independent prognostic factor [adjusted hazard ratio (relative risk) 1.4, 95% confidence intervals (CI) 1.1-1.9 for women above 65 years relative to younger women]. Most (70.5%) tumours were stage III/IV at diagnosis. Three-year survival ranged from 72% among patients with stage I tumours to 7% for stage IV tumours. Overall, there was no survival difference among different histological types in all stages combined. When limited to stages I and II cancers, adenocarcinomas were associated with a better outcome relative to other histological subtypes combined (adjusted relative risk 0.4, 95% CI 0.1-1.0). Smoking was an independent risk factor (adjusted relative risk 1.3, 95% CI 1.0-1.8). Nevertheless, non-smokers comprised 57.4% of this series, highlighting the importance of increased awareness among health professionals and the public that lung cancer is not only a disease of smokers. The high proportion of late-stage tumours in this study and the impact of disease stage on outcome underline the importance of early detection in improving survival of lung cancer.

An unusual case of nephrocutaneous fistula

An 86-year-old Caucasian woman presented with a 2-day history of a painful swelling in the left upper thigh anteriorly. She also gave a recent history of recurrent urinary tract infection associated with macroscopic haematuria, against a background of a long-term indwelling catheter for complete urinary incontinence. She denied any change in bowel habit and her weight had also been stable. Her past history included a hysterectomy, dynamic hip screw insertion for fractured right neck of femur and coronary artery disease.

On examination she was apyrexial with no signs of anaemia, jaundice or lymphadenopathy. The left thigh swelling was confirmed to be an abscess. Abdominal and rectal examinations were unremarkable. The abscess was subsequently incised and drained. A substantial amount of pus was released. Culture of the pus yielded Proteus and Escherichia coli. Unfortunately the left thigh wound failed to heal up completely resulting in a constantly discharging sinus (Figure 1).

A sonogram was then performed which revealed a fistulous track passing closely to the left greater trochanter and then superiorly projected over the left iliac wing. It then tracked medially towards the spine and particularly towards a small staghorn-like calculus on the left side. At no time was contrast seen to spill intra-abdominally (Figure 2). A subsequent computed tomography scan demonstrated that the fistulous track lay anterior to the neck of femur and passed superiorly in front of the hip joint before entering the iliacus muscle compartment retroperitoneally. The contrast then tracked superiorly until it reached the iliac crest. It continued superomedially and retroperitoneally towards the lower pole of the left kidney which contained a staghorn-like calculus. Contrast was also seen in the bladder (Figure 3). The patient did not have intravenous pyelography.

A diethylene triamine pentaacetic acid (DTPA) renogram was carried out which confirmed that the patient had a non-functioning left kidney but good function of the right kidney.

This woman subsequently underwent a left nephrectomy through a midline incision. The left kidney was shrunken and tethered retroperitoneally, and was associated with a well-defined fistulous track. The track was opened and curetted and an associated abscess cavity involving iliacus muscle drained.

Histology of the kidney confirmed chronic pyelonephritis with scarring and presence of calculus in the dilated pelvicalyceal system.

The patient made a straightforward postoperative recovery. At follow-up 3 months postoperatively, the thigh sinus had healed completely and the patient was asymptomatic.

Talk your way round--a speech interface to a virtual museum

PURPOSE

To explore the development of a speech interface to a virtual world and to consider its relevance for disabled users.

METHOD

The system was developed using mainly software that is available at minimal cost. How well the system functioned was assessed by measuring the number of times a group of users with a range of voices had to repeat commands in order for them to be successfully recognized. During an initial session, these users were asked to use the system with no instruction to see how easy this was.

RESULTS

Most of the spoken commands had to be repeated less than twice on average for successful recognition. For a set of 'teleportation' commands this figure was higher (2.4), but it was clear why this was so and could easily be rectified. The system was easy to use without instruction. Comments on the system were generally positive.

CONCLUSIONS

While the system has some limitations, a virtual world with a reasonably reliable speech interface has been developed almost entirely from software which is available at minimal cost. Improvements and further testing are considered. Such a system would clearly improve access to virtual reality (VR) technologies for those without the skills or physical ability to use a standard keyboard and mouse. It is an example of both assistive technology (AT) and universal design.

Mandibular advancement splints and continuous positive airway pressure in patients with obstructive sleep apnoea: a randomized cross-over trial

This prospective, randomized, cross-over trial was designed to compare the efficacy of a mandibular advancement splint (MAS) with that of nasal continuous positive airway pressure (nCPAP) in patients with obstructive sleep apnoea (OSA). Twenty-four patients (20 males and four females) with mild to moderate OSA (AHI between 10 and 49 events per hour) were enrolled in the study. Each patient used both MAS and nCPAP, with the initial therapy being allocated at random. Treatment periods lasted for two months with a two-week wash-out interval between. Polysomnography was performed prior to the study and after each clinical intervention. Patient and partner questionnaires were used to assess changes in general health and daytime somnolence. The AHI decreased from 22.2 to 3.1 using nCPAP, and to 8.0 using the MAS (P < 0.001 for both devices) and there was no statistically significant difference between the two treatments. The Epworth Sleepiness Score (ESS) fell from 13.4 to 8.1 with nCPAP, and to 9.2 with MAS (P < 0.001), again with no differences between the use of MAS or nCPAP. The questionnaire data showed an improvement in general health scores (P < 0.001) after both treatments, but daytime sleepiness only improved significantly using nCPAP (P < 0.001). Despite this, 17 out of the 21 subjects who completed both arms of the study preferred the MAS. The splints were well tolerated and their efficacy suggests that the MAS may be a suitable alternative to nCPAP in the management of patients with mild or moderate OSA.

Recording compliance of dental splint use in obstructive sleep apnoea patients by force and temperature modelling

Fibre-optic sensors are used to monitor the force and temperature of dental splints worn by patients suffering from sleep apnoea. Owing to the small size of the sensors, they can be easily embedded within the splint in a way that does not affect the effectiveness of the splint, and, at the same time, are able to indicate whether the splint has been properly worn by the patient. The overall dimensions of the sensor are approximately 0.375 mm thickness, 1 cm length and 3 mm width. The force and temperature sensors are calibrated and found to have sensitivities of better than 0.5 N and 0.1 degrees C, respectively. Trials performed on patients show that the measurement of pressure and temperature is an effective way of monitoring the proper usage of the dental splint by the patients.

Bilateral gynaecomastia as the primary complaint in hyperthyroidism

Association of gynaecomastia with hyperthyroidism is uncommon but has been well documented in the past. Gynaecomastia in a patient with hyperthyroidism rarely presents as a primary complaint. When this occurs, it may present a diagnostic challenge to the clinician. We present the case of a patient who was referred initially to the breast clinic with bilateral gynaecomastia. Hyperthyroidism was subsequently confirmed and treated; gynaecomastia regressed with return to the euthyroid state.

Building a generic architecture for medical information exchange among healthcare providers

Due to the inability to exchange clinical information among hospitals, continuity of care cannot be maintained and a tremendous amount of medical resource has been wasted. This paper describes an architecture that would facilitate exchange of clinical information among heterogeneous hospital information systems. It is dubbed 'Medical Information Exchange Center' or MIEC as part of a six-year Health Information Network Project hosted by the Department of Health. MIEC was designed so that it is innovative yet technically feasible today. It is convenient for authorized users yet secure enough so people can trust and has minimal impact to participated hospitals. Authorized users will be able to access information through two web-based interfaces directed to physician and non-physician users respectively. Hospitals are connected through a virtual private network to exchange patient information and users need to obtain a private key from the certificate authority in order to securely connect to MIEC. A pilot project was conducted to demonstrate the feasibility of this architecture and the problems encountered were discussed.

Induction chemotherapy followed by concurrent chemoradiotherapy in stage III unresectable non-small cell lung cancer

The favourable experience with the combination regimen of vinorelbine, ifosfamide and cisplatin (NIP) in patients with metastatic non-small cell lung cancer (NSCLC) has led to a protocol assessing this regimen as an induction treatment in patients with stage III unresectable NSCLC, followed by thoracic radiotherapy with concurrent daily cisplatin as a radiosensitizer. Two cycles of NIP were administered 21 days apart; each cycle comprised i.v. vinorelbine 25 mg/m2 on days 1 and 8, i.v. ifosfamide 3 g/m2 on day 1 with MESNA as uroprotection, and i.v. cisplatin 50 mg/m2 on day 1. Radical thoracic radiotherapy commenced on day 43 to a total dose of 64 Gy and i.v. cisplatin 6 mg/m2 was given concurrently prior to each fraction of radiation as a sensitiser. Two more cycles of NIP were given to patients who responded favourably to the induction treatment about 2 weeks after completion of radiation. Between July 1995 and July 1997, 44 patients were treated with this protocol. This treatment schedule was generally well tolerated. Grade 3-4 neutropenia occurred in 50% of the patients and neutropenic sepsis was seen in 8. Grade 3-4 oesophagitis was uncommon. Most of the patients were able to complete the induction and concurrent chemoradiotherapy phase. Major response occurred in 75% of the patients with 2 (4.5%) complete responses (CR). A total of 6 patients achieved CR after chemoradiotherapy. At a median follow-up of 35 months, the median overall survival for all patients was 15 months with a 3-year survival rate of 24%. The median overall survival for stage IIIA patients was 19 months with a 3-year survival rate of 39% in contrast to 13 months' median overall survival and only 15% 3-year survival rate for stage IIIB. The NIP regimen results in a high response rate in NSCLC and this treatment programme seems to benefit selected patients with stage III disease.

Endobronchial mass in a patient with Burkholderia pseudomallei infection

INTRODUCTION

Burkholderia pseudomallei infection, the great mimicker of infectious diseases, has protean clinical manifestations.

CLINICAL PICTURE

A 37-year-old man who presented with community-acquired pneumonia affecting the right upper lobe had unremitting fever. Bronchoscopy showed an endobronchial mass in the right upper lobe bronchus.

TREATMENT

Intravenous ceftriaxone and oral erythromycin, with empiric antituberculous treatment added later. This was subsequently switched to intravenous ceftazidime and oral doxycycline after the diagnosis was made.

OUTCOME

There was resolution of the endobronchial mass.

CONCLUSION

This case illustrates a unique and unreported presentation of melioidosis.

Digital photoplethysmography in the diagnosis of suspected lower limb DVT: is it useful?

OBJECTIVE

to determine the role of digital photoplethysmography (D-PPG) in the diagnosis of deep-vein thrombosis (DVT), in comparison to the "gold standard" of either contrast ascending venography (ACV) or colour-flow duplex imaging (CFDI).

METHOD

prospective study of 100 hospital inpatients (103 legs) referred to the X-ray department for ACV or CFDI with clinically suspected lower limb DVT in a district general hospital. Each patient was assessed by either ACV or CFDI, and D-PPG.

RESULTS

thirty-seven limbs were found to have DVT as demonstrated by ACV or CFDI. All patients with a venous refilling time (RT) of greater than 20 s and venous pump (VP) of greater than 35 had a normal ACV or CFDI. Using RT of less than 21 s as the optimal cut-off point, D-PPG achieved a sensitivity of 100%, negative-predictive value of 100%, specificity of 47% and positive-predictive value of 51%. By using VP of less than 36 as the optimal cut-off point, a sensitivity of 100%, a negative-predictive value of 100%, a specificity of 35% and positive-predictive value of 46% were achieved.

CONCLUSIONS

these results validate the use of portable D-PPG as a useful screening tool for the diagnosis of clinically suspected lower limb DVT. A positive test requires further confirmation by one of the "gold standard" methods, whereas a negative test effectively excludes DVT.

Rapid mycobacterial tuberculosis detection in bronchoalveolar lavage samples by polymerase chain reaction in patients with upper lobe infiltrates and bronchiectasis

In areas where tuberculosis is endemic, a positive sputum acid-fast bacilli (AFB) smear is frequently regarded as almost diagnostic of pulmonary tuberculosis (PTB). The main problem arises when the AFB smear is negative. The main aim of this study was to determine the clinical utility of rapid mycobacterial tuberculosis (MTB) detection in bronchoalveolar lavage (BAL) samples by polymerase chain reaction (PCR) in 52 patients who underwent diagnostic bronchoscopy for suspected PTB. These patients had either upper lobe infiltrates (n = 31) or bronchiectasis (n = 21). Mycobacterial culture is usually used as the gold standard of diagnosis. We chose to define active PTB based on positive mycobacterial cultures and/or histological evidence of caseous necrosis and AFB, and/or when there was clinical plus radiological improvement following therapy. We compared AFB smear, respiratory mycobacterial culture, BAL PCR for MTB and clinical active PTB. Four patients who were smear and culture negative had clinical and radiological clearance following anti-tuberculous therapy showing that using mycobacterial culture as a gold standard may have its limitations. When Kappa (a chance-corrected measure of agreement) was calculated for acid-fast bacilli smear and BAL PCR against our definition of active PTB, it was 0.28 (fair agreement) and 0.73 (substantial agreement), respectively. BAL PCR gave a sensitivity, specificity, positive and negative predictive values of 66.7%, 100%, 100% and 88%, respectively, for the group with upper lobe infiltrates. We also demonstrated that BAL for PCR has a good concordance with the final diagnosis of active tuberculosis.

Ethnicity, obstructive sleep apnoea and ischaemic heart disease

We studied the relationship between different ethnic groups, obstructive sleep apnoea (OSA) and ischaemic heart disease. Four hundred and thirty-two inpatients from the medical wards were interviewed. Limited overnight sleep studies were done in 129 of those who had habitual snoring, daytime sleepiness based on an Epworth sleepiness scale of 8 or more, or a large neck size of 40 cm or more. There were 315 Chinese (72.9%), 67 Malays (15.5%), 43 Indians (10%) and 3 from other races (1.4%). The prevalence of OSA was 19.7%, 30% and 12% among the Chinese, Malays and Indians, respectively. The prevalence ratio for OSA was 1.52 in Malays using Chinese patients as the baseline (P = 0.07). The median neck circumference was 37 cm in both racial groups. The median body mass index was 22.7 kg/m2 in Chinese compared to 23.6 kg/m2 in Malays. The median apnoea-hypopnoea index was 22.7, 19.0 and 26.9 events/hour among the Chinese, Malays and Indians, respectively. OSA was independently associated with the prevalence of IHD (adjusted prevalence ratio 1.68; 95% CI: 1.15, 2.46; P = 0.009). The prevalence of ischaemic heart disease (IHD) was 31%, 24% and 28% in Chinese, Malays and Indians, respectively. The prevalence ratio for IHD in Malays compared to Chinese was 0.77. After adjusting for OSA, there was an even greater reduction in the risk of IHD (adjusted prevalence ratio 0.70). This suggests that OSA is a confounder in the relationship between race and ischaemic heart disease.

Aetiology and outcome of severe community-acquired pneumonia in Singapore

The aim of this study was to determine the aetiology and outcome of severe community-acquired pneumonia, and to assess whether the existing guidelines for initial antimicrobial therapy are being applied. The records of 57 consecutive nonimmunocompromised patients admitted to the medical intensive care unit (ICU) between January 1989 and May 1993 with this diagnosis were reviewed. The microbiological data, chest radiographic changes and outcome were analysed. Nine (16%) of the 57 patients had pulmonary tuberculosis. When these patients were excluded from further analysis, a microbiological diagnosis was made in 41 (72%) cases. The most commonest pathogens were Burkholderia pseudomallei (n=10), Klebsiella spp. (n=5) and Staphylococcus aureus (n=5), Mycoplasma pneumoniae (n=4) and Streptococcus pneumoniae (n=2) were less common. This microbiological spectrum was quite different from that in the West, where the incidence of S. pneumoniae was higher. Also, when pulmonary tuberculosis was excluded, the mortality (67%) was much higher than that in other series. This was attributed to the high incidence of unrecognized B. pseudomallei infection, which is associated with a very high mortality in the region under study. In addition to applying published guidelines on severe community-acquired pneumonia, the endemicity of certain organisms such as Mycobacterium tuberculosis and Burkholderia pseudomallei in different geographical regions needs to be considered when choosing initial empirical antimicrobial therapy.

Four cases of developmental foregut cysts

Four patients with developmental foregut cysts were seen in the Singapore General Hospital between 1991 and 1994. Three had bronchogenic cysts while one had features consistent with both enteric and bronchogenic origin. Among those patients with bronchogenic cysts, only one was symptomatic, having presented with cough and dysphagia. Two other patients presented incidentally on chest radiographs done for pre-National Service enlistment while one patient was picked up when a repeat chest radiograph was done following a course of antibiotics. The diagnosis of our first patient with the symptomatic bronchogenic cyst was based on barium swallow and a computerised tomographic scan of the thorax. Two patients were diagnosed on histology following open thoracotomy and surgical resection of the cysts to have a bronchogenic and a cyst of mixed origin as described above respectively. The last patient who underwent video-assisted thoracoscopic surgery with resection of the cyst was confirmed histologically to have a bronchogenic cyst.

Two cases of lower respiratory tract infection due to Chlamydia pneumonia in Singapore

Chlamydia pneumoniae, previously known as Chlamydia psittaci strain TWAR, causes both upper and lower respiratory tract infection. We report the first two cases of culture-positive Chlamydia pneumoniae lower respiratory infection in Singapore. Both patients had underlying fibrosing alveolitis and presented with a history of prolonged productive cough and fever. Chlamydia pneumoniae was isolated from the bronchoalveolar lavage fluid in the absence of other pathogens. The patients responded clinically to three weeks of oral doxycycline therapy. Infection due to Chlamydia pneumoniae should be considered when a patient with community-acquired pneumonia fails to respond to the usual standard antimicrobial therapy.

Nebulized albuterol in acute childhood asthma: comparison of two doses

Thirty-three children and adolescents from 5 to 17 years of age with moderate to severe acute asthma were given nebulized albuterol therapy in either a high (0.30 mg/kg body weight) or standard (0.15 mg/kg) dose administered at three hourly intervals in a randomized double-blind study. The high-dose hourly regimen resulted in significantly greater improvement in the forced expiratory volume in 1 second (FEV1). Furthermore, patients receiving the high dose showed a steady improvement in the FEV1 from the start to the end of the study, whereas FEV1 plateaued after the second dose in the standard-dose group. Although a rise in heart rate and a fall in serum potassium level occurred, neither of these changes nor other side effects were different in the two groups. The high-dose therapy resulted in much higher serum albuterol levels than the standard dose. There was no correlation between the drug levels and side effects or initial and subsequent FEV1. It is concluded that occasional hourly high-dose albuterol therapy should be considered for some pediatric patients with acute asthma of moderate severity, especially those who relapse between doses.