Molecular Characterization of Circulating Tumor DNA in Pediatric Rhabdomyosarcoma: A Feasibility Study

PURPOSE

Rhabdomyosarcomas (RMS) are rare neoplasms affecting children and young adults. Efforts to improve patient survival have been undermined by a lack of suitable disease markers. Plasma circulating tumor DNA (ctDNA) has shown promise as a potential minimally invasive biomarker and monitoring tool in other cancers; however, it remains underexplored in RMS. We aimed to determine the feasibility of identifying and quantifying ctDNA in plasma as a marker of disease burden and/or treatment response using blood samples from RMS mouse models and patients.

METHODS

We established mouse models of RMS and applied quantitative polymerase chain reaction (PCR) and droplet digital PCR (ddPCR) to detect ctDNA within the mouse plasma. Potential driver mutations, copy-number alterations, and DNA breakpoints associated with PAX3/7-FOXO1 gene fusions were identified in the RMS samples collected at diagnosis. Patient-matched plasma samples collected from 28 patients with RMS before, during, and after treatment were analyzed for the presence of ctDNA via ddPCR, panel sequencing, and/or whole-exome sequencing.

RESULTS

Human tumor-derived DNA was detectable in plasma samples from mouse models of RMS and correlated with tumor burden. In patients, ctDNA was detected in 14/18 pretreatment plasma samples with ddPCR and 7/7 cases assessed by sequencing. Levels of ctDNA at diagnosis were significantly higher in patients with unfavorable tumor sites, positive nodal status, and metastasis. In patients with serial plasma samples (n = 18), fluctuations in ctDNA levels corresponded to treatment response.

CONCLUSION

Comprehensive ctDNA analysis combining high sensitivity and throughput can identify key molecular drivers in RMS models and patients, suggesting potential as a minimally invasive biomarker. Preclinical assessment of treatments using mouse models and further patient testing through prospective clinical trials are now warranted.

POS1361 THE CANADIAN RESEARCH GROUP OF RHEUMATOLOGY IN IMMUNO-ONCOLOGY (CanRIO): A NATIONWIDE MULTI-CENTER PROSPECTIVE COHORT

Background

Immune Checkpoint Inhibitors (ICI) have altered the landscape of cancer therapy. However, toxicities are common and up to 80% of patients will develop immune-related adverse events (irAE), including rheumatic irAEs (Rh-irAE), which can often limit their cancer treatment. Our knowledge of clinical manifestations and optimal management of patients with Rh-irAE continues to evolve as these agents are being used to treat a wider variety of cancers. Currently available data is limited to retrospective case series and case reports. There is also scarce data on the use of ICI in patients with pre-existing autoimmune disease (PAD) as these patients are often excluded from clinical trials.

Objectives

To describe the clinical presentation, management and early outcomes of patients exposed to ICI with Rh-irAE or PAD recruited and followed prospectively from multiple sites across Canada.

Methods

Adult patients with Rh-irAE from cancer immunotherapy (CTLA-4, PD-1 or PDL-1 inhibitors) or those with PAD exposed to cancer immunotherapy are prospectively recruited across 9 academic sites in Canada. Standardized clinical and biologic data are also collected. We describe clinical characteristics and management of patients recruited between January 2020 and October 2021, stratified based on the presence or absence of PAD.

Results

103 patients were recruited from 9 sites. From those, 85 had Rh-irAE, 47 had pre-existing musculoskeletal and rheumatic diseases, and 20 had other PAD. The most frequent Rh-irAE were joint manifestations (n = 73). Other Rh-irAE included muscle symptoms (n = 7), connective tissue disease (n = 6), vasculitis (n=2) and sarcoid (n = 3). Prednisone was the most common treatment (n = 53). Intraarticular corticosteroids were used in 7 patients. Eleven patients required conventional synthetic disease-modifying anti-rheumatic drugs (DMARD) and only one required biologic DMARD to control the Rh-irAE. Anti-PD-1 therapies were the most used ICI (56.3%), followed by combination therapy (35.9%). Response to index immunotherapy at 6 months was available for 21 patients. Most patients had partial response (57.1%) and only 4 patients had tumor progression (19.1%). The ICI was permanently discontinued due to an irAE in 21 patients (38.1% with PAD and 61.9% without PAD). There were no deaths related to Rh-irAE.

Conclusion

The initial sample of the CanRIO prospective national cohort suggests that demographic characteristics and tumor representation in people with PAD and without PAD is similar. Patients with PAD are less likely to receive combination therapy (n= 12 vs. n=25) and are less likely to have tumor progression on ICI (n=1) compared to those without PAD (n=3). Selection bias is noted in this initial sample since half of recruited patients have PAD. The CanRIO cohort provides valuable insight into real-world spectrum and management of Rh-irAE secondary to immunotherapy for cancer.

Disclosure of Interests

Shahin Jamal Grant/research support from: CanRIO has received financial support from BMS and Organon, Lourdes Gonzalez Arreola: None declared, Julia Tan: None declared, Carrie Ye: None declared, Janet Roberts: None declared, Aurore Fifi-Mah: None declared, Marie Hudson: None declared, Sabrina Hoa: None declared, Janet Pope: None declared, Ines Colmegna: None declared, C. Thomas Appleton: None declared

Circulating tumour DNA sequencing to determine therapeutic response and identify tumour heterogeneity in patients with paediatric solid tumours

OBJECTIVE

Clinical diagnostic sequencing of circulating tumour DNA (ctDNA) is well advanced for adult patients, but application to paediatric cancer patients lags behind.

METHODS

To address this, we have developed a clinically relevant (67 gene) NGS capture panel and accompanying workflow that enables sensitive and reliable detection of low-frequency genetic variants in cell-free DNA (cfDNA) from children with solid tumours. We combined gene panel sequencing with low pass whole-genome sequencing of the same library to inform on genome-wide copy number changes in the blood.

RESULTS

Analytical validity was evaluated using control materials, and the method was found to be highly sensitive (0.96 for SNVs and 0.97 for INDEL), specific (0.82 for SNVs and 0.978 for INDEL), repeatable (>0.93 [95% CI: 0.89-0.95]) and reproducible (>0.87 [95% CI: 0.87-0.95]). Potential for clinical application was demonstrated in 39 childhood cancer patients with a spectrum of solid tumours in which the single nucleotide variants expected from tumour sequencing were detected in cfDNA in 94.4% (17/18) of cases with active extracranial disease. In 13 patients, where serial samples were available, we show a close correlation between events detected in cfDNA and treatment response, demonstrate that cfDNA analysis could be a useful tool to monitor disease progression, and show cfDNA sequencing has the potential to identify targetable variants that were not detected in tumour samples.

CONCLUSIONS

This is the first pan-cancer DNA sequencing panel that we know to be optimised for cfDNA in children for blood-based molecular diagnostics in paediatric solid tumours.

399 Complex Limb Injuries – Limb Salvage vs Amputation: An Overview of the Factors Influencing Decision-Making and Outcomes

Aim

Complex limb injuries usually comprise of a combination of osseous, soft tissue, vascular and neural damage, necessitating prompt and accurate initial examination and decision-making to maximise optimal patient outcomes. We present the factors affecting the decision-making as well as the outcomes following primary limb amputation or salvage of complex extremity injuries, with an emphasis on the various scoring systems present that endeavour to offer prognostic and therapeutic guidance to orthopaedic surgeons.

Method

We performed the literature search on PubMed and Embase, and collated the relevant data comprising of demographics, injury, scoring system, primary and secondary outcome metrics and complications.

Results

Many scoring systems, each with variable factors, have been proposed to predict limb salvage vs amputation in complex extremity injury (MESS, PSI, LSI, NISSSA, HFS-97), however the landmark LEAP trial concluded in its final analysis that they could not validate them. Whilst the scores were useful in predicting limb salvage, they were inaccurate and unreliable in predicting amputation with low sensitivities

Conclusions

Many scoring systems attempt to provide guidance regarding decision-making in limb salvage vs primary amputation, however the LEAP study has shown poor predictive standards of these systems. As such, there is no gold standard algorithmic approach or scoring system when making this difficult decision – instead, the poor predictors of limb salvage have been identified, and the surgeons need to be judicious and make a joint decision considering these variables and other patient factors (social, economic, and psychological status).

358 Surgical Management of Spinal Cord Injuries: An Overview of Controversies

Aim

Spinal Cord Injuries (SCI) are incredibly debilitating injuries associated with significant morbidity and financial burden, with an incidence of 12-16 per million population in the UK. There is currently no cure for SCI, with majority of interventions focusing on primary prevention of SCI or of further damage once SCI is sustained. We present an overview of the role of closed reduction, timing of surgery and role of steroids, and provide an algorithm for management of SCI.

Method

A search was carried out on PubMed, looking at notable reviews, consensus statements and trends in management of spinal cord injuries. This was cross-referenced with the NICE and BOAST guidelines for SCI.

Results

The efficacy of closed reduction in cervical fractures and necessity of pre-reduction MRI is still equivocal and remains a source of major debate amongst spinal surgeons. The timing of surgery remains controversial as studies have not consistently shown improved outcomes with early, aggressive surgery but there have been trends noted in the newer studies with some benefit of early surgery. The use of steroids in acute SCI has fallen out of favour with most guidelines not recommending them due to their equivocal benefit and unequivocal side-effect profile.

Conclusions

Prevention and pre-hospital management are crucial in the management of SCI, along with early spinal alignment restoration, decompression and stabilisation augmented by good long-term rehabilitation measures. There is a need for new randomised controlled trials assessing the role of closed reduction, need for pre-reduction MRI and timing of surgery in SCI.

Genomic Classification and Clinical Outcome in Rhabdomyosarcoma: A Report From an International Consortium

PURPOSE

Rhabdomyosarcoma is the most common soft tissue sarcoma of childhood. Despite aggressive therapy, the 5-year survival rate for patients with metastatic or recurrent disease remains poor, and beyond PAX-FOXO1 fusion status, no genomic markers are available for risk stratification. We present an international consortium study designed to determine the incidence of driver mutations and their association with clinical outcome.

PATIENTS AND METHODS

Tumor samples collected from patients enrolled on Children's Oncology Group trials (1998-2017) and UK patients enrolled on malignant mesenchymal tumor and RMS2005 (1995-2016) trials were subjected to custom-capture sequencing. Mutations, indels, gene deletions, and amplifications were identified, and survival analysis was performed.

RESULTS

DNA from 641 patients was suitable for analyses. A median of one mutation was found per tumor. In FOXO1 fusion-negative cases, mutation of any RAS pathway member was found in > 50% of cases, and 21% had no putative driver mutation identified. BCOR (15%), NF1 (15%), and TP53 (13%) mutations were found at a higher incidence than previously reported and TP53 mutations were associated with worse outcomes in both fusion-negative and FOXO1 fusion-positive cases. Interestingly, mutations in RAS isoforms predominated in infants < 1 year (64% of cases). Mutation of MYOD1 was associated with histologic patterns beyond those previously described, older age, head and neck primary site, and a dismal survival. Finally, we provide a searchable companion database (ClinOmics), containing all genomic variants, and clinical annotation including survival data.

CONCLUSION

This is the largest genomic characterization of clinically annotated rhabdomyosarcoma tumors to date and provides prognostic genetic features that refine risk stratification and will be incorporated into prospective trials.

COVID-19 recovery: tackling the 2-week wait colorectal pathway backlog by optimising CT colonography utilisation

AIM

To review the indications for computed tomography colonography (CTC) performed on patients referred via the 2-week wait colorectal pathway (2WWCP).

MATERIALS AND METHODS

A retrospective study was performed on all patients referred through the 2WWCP between October 2018 and September 2019. The referrals were audited against the National Institute for Health and Care Excellence (NICE) NG12/DG30 guidelines for referral to the 2WWCP, and against the Royal College of Radiologists (RCR) 2017 guidelines for CTC.

RESULTS

Over the study period, there were 1,707 2WWCP referrals, and 362 (21.2%) of these patients underwent CTC. The median age was 66 years, and 55% were female. Forty-six patients did not meet the NICE NG12/DG30 guidelines for referral to the 2WWCP, and a further 268, although meeting the NICE guidelines, did not meet the RCR 2017 guidelines for CTC. In total, only 13% of CTCs performed complied with both guidelines.

CONCLUSION

This audit demonstrated a significant opportunity to reallocate CTC resources in the recovery stage of the COVID-19 pandemic. To improve outcomes for colorectal cancer (CRC) in the UK, establishing a selective straight-to-test CTC 2WWCP should be considered. Documented consent detailing the risks and benefits of CTC versus colonoscopy should take place in order to assist the patient in making an informed choice.

Association between known risk factors and colorectal cancer risk in Indigenous people participating in the Ontario Familial Colon Cancer Registry

Introduction

Colorectal cancer is one of the most common cancers in Ontario and imposes a high burden on many Indigenous populations. There are two aims for this short communication: ■ Highlight colorectal risk factor findings from a population-based case-control study■ Highlight trends and challenges of colorectal cancer research in Indigenous populations in Ontario.

Methods

Prevalences of cigarette smoking, obesity, fruit and vegetable consumption, and family history of colorectal cancer were estimated using the Indigenous identifier in the Ontario Familial Colon Cancer Registry for 1999-2007 and then compared for cases and controls using age-adjusted odds ratios (ors) with 95% confidence intervals (cis).

Results

The registry search identified 66 Indigenous cases and 23 Indigenous controls. Cigarette smoking (or: 1.88; 95% ci: 0.63 to 5.60) and obesity (or: 2.16; 95% ci: 0.72 to 6.46) were higher in cases, but not statistically significantly so.

Conclusions

Findings were consistent with previous literature describing Indigenous populations. A small sample size and poor Indigenous identification questions make it challenging to comprehensively understand cancer risk factors and burden in Indigenous populations.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

A tailored molecular profiling programme for children with cancer to identify clinically actionable genetic alterations

BACKGROUND

For children with cancer, the clinical integration of precision medicine to enable predictive biomarker-based therapeutic stratification is urgently needed.

METHODS

We have developed a hybrid-capture next-generation sequencing (NGS) panel, specifically designed to detect genetic alterations in paediatric solid tumours, which gives reliable results from as little as 50 ng of DNA extracted from formalin-fixed paraffin-embedded (FFPE) tissue. In this study, we offered an NGS panel, with clinical reporting via a molecular tumour board for children with solid tumours. Furthermore, for a cohort of 12 patients, we used a circulating tumour DNA (ctDNA)-specific panel to sequence ctDNA from matched plasma samples and compared plasma and tumour findings.

RESULTS

A total of 255 samples were submitted from 223 patients for the NGS panel. Using FFPE tissue, 82% of all submitted samples passed quality control for clinical reporting. At least one genetic alteration was detected in 70% of sequenced samples. The overall detection rate of clinically actionable alterations, defined by modified OncoKB criteria, for all sequenced samples was 51%. A total of 8 patients were sequenced at different stages of treatment. In 6 of these, there were differences in the genetic alterations detected between time points. Sequencing of matched ctDNA in a cohort of extracranial paediatric solid tumours also identified a high detection rate of somatic alterations in plasma.

CONCLUSION

We demonstrate that tailored clinical molecular profiling of both tumour DNA and plasma-derived ctDNA is feasible for children with solid tumours. Furthermore, we show that a targeted NGS panel-based approach can identify actionable genetic alterations in a high proportion of patients.

Engineering a palette of eukaryotic chromoproteins for bacterial synthetic biology

Background

Coral reefs are colored by eukaryotic chromoproteins (CPs) that are homologous to green fluorescent protein. CPs differ from fluorescent proteins (FPs) by intensely absorbing visible light to give strong colors in ambient light. This endows CPs with certain advantages over FPs, such as instrument-free detection uncomplicated by ultra-violet light damage or background fluorescence, efficient Förster resonance energy transfer (FRET) quenching, and photoacoustic imaging. Thus, CPs have found utility as genetic markers and in teaching, and are attractive for potential cell biosensor applications in the field. Most near-term applications of CPs require expression in a different domain of life: bacteria. However, it is unclear which of the eukaryotic CP genes might be suitable and how best to assay them.

Results

Here, taking advantage of codon optimization programs in 12 cases, we engineered 14 CP sequences (meffRed, eforRed, asPink, spisPink, scOrange, fwYellow, amilGFP, amajLime, cjBlue, meffBlue, aeBlue, amilCP, tsPurple and gfasPurple) into a palette of Escherichia coli BioBrick plasmids. BioBricks comply with synthetic biology’s most widely used, simplified, cloning standard. Differences in color intensities, maturation times and fitness costs of expression were compared under the same conditions, and visible readout of gene expression was quantitated. A surprisingly large variation in cellular fitness costs was found, resulting in loss of color in some overnight liquid cultures of certain high-copy-plasmid-borne CPs, and cautioning the use of multiple CPs as markers in competition assays. We solved these two problems by integrating pairs of these genes into the chromosome and by engineering versions of the same CP with very different colors.

Conclusion

Availability of 14 engineered CP genes compared in E. coli, together with chromosomal mutants suitable for competition assays, should simplify and expand CP study and applications. There was no single plasmid-borne CP that combined all of the most desirable features of intense color, fast maturation and low fitness cost, so this study should help direct future engineering efforts.

Electronic supplementary material

The online version of this article (10.1186/s13036-018-0100-0) contains supplementary material, which is available to authorized users.

Primary tuberculosis of palate

Primary tuberculosis (TB) of the hard palate is very rare. A 74-year-old man was presented with 6-month history of dysphagia along with an irregular mass in the hard and soft palate. Magnetic resonance imaging (MRI) revealed thickened and increased signal intensity within hard and soft palate. Tissue biopsy showed focal caseating granulomatous-like lesion and the histochemical staining using Ziehl-Neelsen stain for acid-fast bacilli was positive. Positive histochemical studies provided evidences that the hard palate mass was most likely due to TB. Thus, the patient was started on antituberculous therapy.

Is universal sample processing methodology better than conventional techniques for detection of tuberculosis?

BACKGROUND

The identification of infectious cases is a crucial first step for tuberculosis control programmes worldwide. It relies exclusively on the detection of acid-fast bacilli in sputum by smear microscopy. Therefore, there is an urgent and definite need to improve the sensitivity of smear microscopy.

OBJECTIVE

The USP method was compared with the two most commonly used conventional methods of smear microscopy namely; direct smear microscopy and the microscopy by modified Petroff's method.

MATERIALS AND METHODS

Two samples from each patient were taken from 197 patients of presumptive tuberculosis. One smear was made for direct Ziehl-Neelsen staining and two smears were made after processing by two concentration methods i.e., modified Petroff's and USP solution. LJ media were inoculated for culture after processing by both concentration methods.

RESULTS

Among 197 cases 93 were culture positive by either method. Out of 93 culture-positive sample, 78.5% were direct smear positive, 89% were 4%NaOH smear positive and 96% were USP smear-positive samples but difference in diagnostic accuracy of USP (96%) and modified Petroff method (93%) is not statistically significant (P>0.01).

CONCLUSION

The present study evaluated the smear microscopy by USP method with two conventional methods, direct microscopy and microscopy by modified Petroff's method. The study concludes that although USP method is more sensitive than conventional methods, it is not feasible to include it in diagnosis of early tuberculosis within RNTCP.

A novel approach to analyzing concentration polarization of polysaccharide solutions

This paper describes a novel approach to analyzing the concentration polarization (CP) in the short-time constant flux filtration of polysaccharide solutions. With application of the pearl-necklace model based polymer solution permeability correlation, a transmembrane pressure (TMP) increase rate model was developed to relate the linear TMP increase rate measured in the short-time constant flux filtration to the solid concentration at the membrane surface, the polymer critical overlapping concentration, and the radius of gyration of the polymer molecules. Establishment of such a theoretical model allows analysis of the gelation propensity of the CP layer formed by polysaccharides based on the experimentally determined linear TMP increase rate.

Spindle cell rhabdomyosarcoma of the tongue – A rare entity

Spindle cell variant of Rhabdomyosarcoma is a rare malignant tumor in adults but even more so in tongue. We report a case of a 17 year old boy who presented with a polypoidal swelling on the tip of the tongue. The mass was excised and the specimen was sent to the Histopathology Department of Armed Forces Institute of Pathology for Histomorphological diagnosis. The histological evaluation showed a malignant spindle cell tumor. On the basis of morphological features and immunohistochemistry findings a final diagnosis of Rhabdomyosarcoma, Spindle cell variant was made. Journal of College of Medical Sciences-Nepal,2011,Vol-7,No-4, 63-66 DOI: http://dx.doi.org/10.3126/jcmsn.v7i4.6814

A clinical decision rule to enhance targeted bone mineral density testing in healthy mid-life women

SUMMARY

The rates of bone mineral density testing for osteoporosis among healthy mid-life women are high, although their osteoporosis or fracture risk is low. To reduce unnecessary testing, we created and evaluated a tool to guide bone density testing based on the woman's age, weight, fracture history, and menopausal status.

INTRODUCTION

This study aims to improve case finding of mid-life women with low bone mass on bone mineral density (BMD) assessment.

METHODS

Among healthy women aged 40-60 years having their first BMD test, osteoporosis risk factors were assessed by questionnaire and BMD by dual-energy X-ray absorptiometry. The combination of risk factors that best discriminated women with/without low bone mass (T-score ≤ -2.0) was determined from the logistic regression model area under the curve (AUC) and internally validated using bootstrapping. Using the model odds ratios, a clinical prediction rule was created and its discriminative properties assessed and compared with that of the osteoporosis self-assessment tool (OST). Sensitivity analyses examined results for pre-/peri- and post-menopausal women, separately.

RESULTS

Of 1,664 women referred for baseline BMD testing, 433 with conditions known to be associated with bone loss were excluded. Of 1,231 eligible women, 944 (77%) participated and 87 (9.2%) had low bone mass (35 pre-/peri- and 52 post-menopausal). Four risk factors for low bone mass were identified and incorporated into a clinical prediction rule. Selecting women for BMD testing with weight of ≤70 kg or any two of age >51, years' post-menopause of ≥1, and history of fragility fracture after age 40 was associated with 93% sensitivity to identify women with low bone mass, compared with 47% sensitivity for an OST score of ≤1 (AUC 0.75 versus OST AUC 0.69, p = 0.04). Results restricted to post-menopausal women were similar.

CONCLUSIONS

Among healthy mid-life women receiving a baseline BMD test, few had low bone mass, supporting the need for guidance about testing. A prediction rule with four risk factors had improved sensitivity over the OST. Further validation is warranted.

Construction and validation of a simplified fracture risk assessment tool for Canadian women and men: results from the CaMos and Manitoba cohorts

A procedure for creating a simplified version of fracture risk assessment tool (FRAX®) is described. Calibration, fracture prediction, and concordance were compared with the full FRAX tool using two large, complementary Canadian datasets.

INTRODUCTION

The Canadian Association of Radiologists and Osteoporosis Canada (CAROC) system for fracture risk assessment is based upon sex, age, bone mineral density (BMD), prior fragility fracture, and glucocorticoid use. CAROC does not require computer or web access, and categorizes 10-year major osteoporotic fracture risk as low (<10%), moderate (10-20%), or high (>20%).

METHODS

Basal CAROC fracture risk tables (by age, sex, and femoral neck BMD) were constructed from Canadian FRAX probabilities for major osteoporotic fractures (adjusted for prevalent clinical risk factors). We assessed categorization and fracture prediction with the updated CAROC system in the CaMos and Manitoba BMD cohorts.

RESULTS

The new CAROC system demonstrated high concordance with the Canadian FRAX tool for risk category in both the CaMos and Manitoba cohorts (89% and 88%). Ten-year fracture outcomes in CaMos and Manitoba BMD cohorts showed good discrimination and calibration for both CAROC (6.1-6.5% in low-risk, 13.5-14.6% in moderate-risk, and 22.3-29.1% in high-risk individuals) and FRAX (6.1-6.6% in low-risk, 14.4-16.1% in moderate-risk, and 23.4-31.0% in high-risk individuals). Reclassification from the CAROC risk category to a different risk category under FRAX occurred in <5% for low-risk, 20-24% for moderate-risk, and 27-30% for high-risk individuals. Reclassified individuals had 10-year fracture outcomes that were still within or close to the original nominal-risk range..

CONCLUSION

The new CAROC system is well calibrated to the Canadian population and shows a high degree of concordance with the Canadian FRAX tool. The CAROC system provides s a simple alternative when it is not feasible to use the full Canadian FRAX tool.

Fracture prediction and calibration of a Canadian FRAX® tool: a population-based report from CaMos

A new Canadian WHO fracture risk assessment (FRAX®) tool to predict 10-year fracture probability was compared with observed 10-year fracture outcomes in a large Canadian population-based study (CaMos). The Canadian FRAX tool showed good calibration and discrimination for both hip and major osteoporotic fractures.

INTRODUCTION

The purpose of this study was to validate a new Canadian WHO fracture risk assessment (FRAX®) tool in a prospective, population-based cohort, the Canadian Multicentre Osteoporosis Study (CaMos).

METHODS

A FRAX tool calibrated to the Canadian population was developed by the WHO Collaborating Centre for Metabolic Bone Diseases using national hip fracture and mortality data. Ten-year FRAX probabilities with and without bone mineral density (BMD) were derived for CaMos women (N = 4,778) and men (N = 1,919) and compared with observed fracture outcomes to 10 years (Kaplan-Meier method). Cox proportional hazard models were used to investigate the contribution of individual FRAX variables.

RESULTS

Mean overall 10-year FRAX probability with BMD for major osteoporotic fractures was not significantly different from the observed value in men [predicted 5.4% vs. observed 6.4% (95%CI 5.2-7.5%)] and only slightly lower in women [predicted 10.8% vs. observed 12.0% (95%CI 11.0-12.9%)]. FRAX was well calibrated for hip fracture assessment in women [predicted 2.7% vs. observed 2.7% (95%CI 2.2-3.2%)] but underestimated risk in men [predicted 1.3% vs. observed 2.4% (95%CI 1.7-3.1%)]. FRAX with BMD showed better fracture discrimination than FRAX without BMD or BMD alone. Age, body mass index, prior fragility fracture and femoral neck BMD were significant independent predictors of major osteoporotic fractures; sex, age, prior fragility fracture and femoral neck BMD were significant independent predictors of hip fractures.

CONCLUSION

The Canadian FRAX tool provides predictions consistent with observed fracture rates in Canadian women and men, thereby providing a valuable tool for Canadian clinicians assessing patients at risk of fracture.

Fragility fractures and the osteoporosis care gap in women: the Canadian Multicentre Osteoporosis Study

Canadian women over 50 years old were studied over a 10-year period to see if those who sustained a fracture (caused by minimal trauma) were receiving the recommended osteoporosis therapy. We found that approximately half of these women were not being treated, indicating a significant care gap in osteoporosis treatment.

INTRODUCTION

Prevalent fragility fracture strongly predicts future fracture. Previous studies have indicated that women with fragility fractures are not receiving the indicated treatment. We aimed to describe post fracture care in Canadian women using a large, population-based prospective cohort that began in 1995-1997.

METHODS

We followed 5,566 women over 50 years of age from across Canada over a period of 10 years in the Canadian Multicentre Osteoporosis Study. Information on medication use and incident clinical fragility fractures was obtained during a yearly questionnaire or interview and fractures were confirmed by radiographic/medical reports.

RESULTS

Over the 10-year study period, 42-56% of women with yearly incident clinical fragility fractures were not treated with an osteoporosis medication. During year 1 of the study, 22% of the women who had experienced a fragility fracture were on treatment with a bisphosphonate and 26% were on hormone therapy (HT). We were not able to differentiate HT use for menopause symptoms vs osteoporosis. Use of bisphosphonate therapy increased over time; odds ratio (OR) for use at year 10 compared to use at year 1 was 3.65 (95% confidence interval (CI) 1.83-7.26). In contrast, HT use declined, with an OR of 0.07 (95%CI 0.02-0.24) at year 10 compared to year 1 of the study.

CONCLUSION

In a large population-based cohort study, we found a therapeutic care gap in women with osteoporosis and fragility fractures. Although bisphosphonate therapy usage improved over time, a substantial gap remains.

Arenaviruses and hantaviruses: from epidemiology and genomics to antivirals

The arenaviruses and hantaviruses are segmented genome RNA viruses that are hosted by rodents. Due to their association with rodents, they are globally widespread and can infect humans via direct or indirect routes of transmission, causing considerable human morbidity and mortality. Nevertheless, despite their obvious and emerging importance as pathogens, there are currently no effective antiviral drugs (except ribavirin which proved effective against Lassa virus) with which to treat humans infected by any of these viruses. The EU-funded VIZIER project (Comparative Structural Genomics of Viral Enzymes Involved in Replication) was instigated with an ultimate view of contributing to the development of antiviral therapies for RNA viruses, including the arenaviruses and bunyaviruses. This review highlights some of the major features of the arenaviruses and hantaviruses that have been investigated during recent years. After describing their classification and epidemiology, we review progress in understanding the genomics as well as the structure and function of replicative enzymes achieved under the VIZIER program and the development of new disease control strategies.

Enteropathy associated T-cell lymphoma resulting in restrictive cardiomyopathy and mimicking myocardial infarction

A 64-year-old woman was referred with a short history of abdominal pain, anorexia and weight loss. Investigations revealed a probable enteropathy associated T-cell lymphoma (EATL). Further investigations revealed evidence of what appeared to be a myocardial infarction. After going through laparoscopy to obtain diagnostic tissue, the patient developed cardiogenic shock which proved refractory to medical therapy. Postmortem examination revealed diffuse abdominal lymphoma consistent with EATL. Surprisingly, there was extensive infiltration of the myocardium. This report demonstrates an unusual pathology resulting from EATL and discusses the limited evidence relating to cardiac involvement of this disease.

Understanding the alphaviruses: recent research on important emerging pathogens and progress towards their control

The alphaviruses were amongst the first arboviruses to be isolated, characterized and assigned a taxonomic status. They are globally very widespread, infecting a large variety of terrestrial animals, insects and even fish, and circulate both in the sylvatic and urban/peri-urban environment, causing considerable human morbidity and mortality. Nevertheless, despite their obvious importance as pathogens, there are currently no effective antiviral drugs with which to treat humans or animals infected by any of these viruses. The EU-supported project-VIZIER (Comparative Structural Genomics of Viral Enzymes Involved in Replication, FP6 PROJECT: 2004-511960) was instigated with an ultimate view of contributing to the development of antiviral therapies for RNA viruses, including the alphaviruses [Coutard, B., Gorbalenya, A.E., Snijder, E.J., Leontovich, A.M., Poupon, A., De Lamballerie, X., Charrel, R., Gould, E.A., Gunther, S., Norder, H., Klempa, B., Bourhy, H., Rohayemj, J., L'hermite, E., Nordlund, P., Stuart, D.I., Owens, R.J., Grimes, J.M., Tuckerm, P.A., Bolognesi, M., Mattevi, A., Coll, M., Jones, T.A., Aqvist, J., Unger, T., Hilgenfeld, R., Bricogne, G., Neyts, J., La Colla, P., Puerstinger, G., Gonzalez, J.P., Leroy, E., Cambillau, C., Romette, J.L., Canard, B., 2008. The VIZIER project: preparedness against pathogenic RNA viruses. Antiviral Res. 78, 37-46]. This review highlights some of the major features of alphaviruses that have been investigated during recent years. After describing their classification, epidemiology and evolutionary history and the expanding geographic distribution of Chikungunya virus, we review progress in understanding the structure and function of alphavirus replicative enzymes achieved under the VIZIER programme and the development of new disease control strategies.

Renal function and rate of hip bone loss in older men: the Osteoporotic Fractures in Men Study

Older men with reduced renal function are at increased risk of hip bone loss. Given the robustness of this association across different measures and a growing body of literature, our findings indicate that clinicians should take into account renal function when evaluating older men for osteoporosis risk and bone loss. Future randomized controlled trials should test whether interventions in this high risk population are effective in preventing bone loss and decreasing fracture incidence.

INTRODUCTION

Studies examining whether kidney impairment, not requiring dialysis, is associated with osteoporosis have reported conflicting results.

METHODS

We tested the hypothesis that reduced renal function in older men as manifested by higher concentrations of cystatin C or lower levels of estimated glomerular filtration rate (eGFR) is associated with higher rates of bone loss. We measured serum cystatin C, serum creatinine and total hip bone mineral density (BMD) at baseline in a cohort of 404 older men enrolled in the Osteoporotic Fractures in Men (MrOS) Study and followed them prospectively for an average of 4.4 years for changes in BMD. Associations between renal function and change in hip BMD were examined using linear regression.

RESULTS

In multivariable analysis, the mean rate of decline in total hip BMD showed an increase in magnitude with higher cystatin C concentration (mean annualized percent change -0.29, -0.34, -0.37 and -0.65% for quartiles 1 to 4; p for trend=0.004). Similarly, adjusted rates of hip bone loss were higher among men with lower eGFR as defined by the modification of diet in renal disease formula (mean annualized percent change -0.58, -0.39, -0.37, and -0.31 for quartiles 1 to 4; p for trend=0.02), but not among men with lower eGFR as defined by the Cockcroft-Gault formula (mean annualized percent change -0.47, -0.44, -0.31 and -0.43 for quartiles 1 to 4; p for trend=0.48).

CONCLUSIONS

Older men with reduced renal function are at increased risk of hip bone loss. Our findings suggest that health care providers should consider renal function when evaluating older men for risk factors for bone loss and osteoporosis.

Complementary and alternative medicine use by osteoporosis clinic patients

We describe complementary and alternative medicine use (CAM) in 360 patients attending osteoporosis clinics. Of these patients, 57% were CAM users. Predictors of CAM use included lower mental quality of life, younger age and higher education. Less than half of CAM use was disclosed to physicians, despite potential adverse interactions.

INTRODUCTION

The prevalence of complementary and alternative medicine (CAM) use in osteoporosis clinics is not known. The objective of this study was to describe the pattern of CAM use in this population.

METHODS

We performed a cross-sectional study of 360 patients attending academic osteoporosis clinics in Toronto, Canada in 2001. Subjects completed a self-administered questionnaire on CAM use. Health-related quality of life (HQL) was measured with the Short-Form 36v2. Comparative statistics and logistic regression were performed to identify sociodemographic, HQL and clinical correlates of CAM use.

RESULTS

More than 80% of participants were women, Caucasian and had at least a high school education. Of subjects, 57% used CAM in the previous year. Only 44% of CAM use was disclosed to a medical doctor. CAM users and non-users did not differ in clinical characteristics such as bone mineral density, level of comorbidity and fracture history. In univariate analysis, CAM users were less satisfied with conventional medicine. However, when we explored patient satisfaction, comorbidities and sociodemographic as predictors for CAM use, the multivariable analyses showed that lower mental HQL, younger age, and post-secondary education were the only significant predictors. We identified 35 cases in which the utilization of CAM supplements could possibly exacerbate existing medical conditions.

CONCLUSION

Patients attending osteoporosis clinics frequently use CAM. Conceptually, the predictors of use identified in this study may fit into a socio-behavioral model that helps explain why people turn to CAM. Physicians may need to elicit a history of CAM use more vigilantly so as to better screen for possible adverse clinical interactions.

Building capacity for improved veterinary epidemiosurveillance in southern Africa

A workshop to produce recommendations on training requirements for improved epidemiosurveillance of livestock diseases in southern Africa was organised at the Department of Veterinary Tropical Diseases in the Veterinary Faculty of the University of Pretoria. It was attended by 23 persons representing 10 different southern African countries. The majority of the participants were actively involved in veterinary epidemiosurveillance and many of them were members of the SADC Epidemiology and Informatics Subcommittee. Discussions focused on (i) epidemiosurveillance networks and their 2 main components, i.e. (ii) diagnosis and (iii) information flow. The debates were guided by 3 questions; (i) what are the requirements for an effective network, (ii) what cannot be achieved with existing capacity and (iii) how can the current capacity be improved. Workshop participants developed lists of realistic capacity building needs, which were divided into structural needs and training requirements. Structural needs mainly concerned communication means and quality assurance. With regard to training, the need for appropriate continuing education of all actors at the various disease management levels (non-professional, para-professional, professional) was expressed. Special emphasis was put on capacity building at the lowest level, i.e. the livestock owner and the para-professionals at the community level. At the international level, it was felt that special emphasis should be put on building capacity to improve the understanding of international agreements on trade in animals and animal products and to improve the capacity of negotiating such agreements.

Lymph nodo-venous shunt in the treatment of protein losing enteropathy and lymphedema of leg and scrotum

Protein Losing Enteropathy (PLE) is a syndrome associated with several diseases affecting the gastrointestinal system. Recent comprehensive reviews can be found in eMedicine and Gastroenterology. Treatment by surgery, lympho-venous anastomosis, excision of lymphangiectatic small bowel and gastrectomy and transplantation of the small intestine, depending upon the cause, have all been reported. We obtained a successful result for PLE associated with peripheral lymphedema by combining several sequential operative approaches including lymph nodo- venous shunt in the groin and reduction surgery for edema of the left leg and scrotum.

The susceptibility of Trypanosoma congolense isolated in Zambézia Province, Mozambique, to isometamidium chloride, diminazene aceturate and homidium chloride

Resistance to trypanocidal drugs has been detected in various African countries and is a serious impediment to the control of livestock trypanosomosis. To determine whether drug resistant trypanosome strains are present in the Zambézia Province of Mozambique a study was initiated. To assess the effect of the farming system and the drug-use regimen on the development of drug resistance, trypanosome isolates were collected from cattle from subsistence and commercial livestock production systems. The susceptibility of seven isolates against isometamidium chloride, diminazene aceturate and homidium chloride was tested in mice using a multiple-dose test. In four of the seven isolates high levels of drug resistance to diminazene aceturate and isometamidium chloride were detected. In most cases the observed levels of drug resistance correlated with the drug-use practices in the particular livestock production system.

Investigation of conformational changes induced by binding of pancreatic RNase to anti-RNase IgG derived Fab monomer using optical procedures

The conformational changes induced in Fab fragments of polyclonal anti-RNase antibody molecules obtained by digestion with papain as a result of binding of pancreatic RNase have been studied. The RNase-Fab complex (RN-Fab), being soluble, could be subjected to thermodynamic investigations using optical strategies, also because of the absence of tryptophan in RNase. Internalization of the chromophores (tryptophans and tyrosines) of Fab occurs when it binds to RNase, suggesting an increase in the compactness of Fab due to the binding of RNase.

The role of complement testing in dermatology

An up-to-date knowledge of the molecular events involved in the activation and control of the complement cascade is essential to understand the pathogenesis of a number of conditions presenting to dermatologists. This knowledge underpins the pathogenesis of these conditions but allows the clinician to request the most useful tests in terms of diagnosis and monitoring. In this review we aim to discuss complement biology, the diseases in which complement testing is of particular relevance, the types of laboratory tests available, their utility and interpretation. Additionally it is of critical importance for clinicians not only to choose the most appropriate tests but also to choose to send these to an appropriately accredited laboratory.

The effectiveness of long-acting penicillin (penidur) in preventing recurrences of dermatolymphangioadenitis(DLA) and controlling skin, deep tissues, and lymph bacterial flora in patients with "filarial" lymphedema

Dermatolymphangioadenitis (DLA) is a common and serious complication of so-called "filarial" and bacterial non-filarial lymphedema of the limb, affecting skin, lymphatics and lymph nodes. In our previous studies, we demonstrated that more than 60% of patients revealed presence of bacterial isolates in deep tissues, tissue fluid and lymph from the lymphedematous limbs. The question remained open whether elimination or suppression of bacteria dwelling in lymphedematous tissues by administration of low doses of penicillin for long time periods would prevent recurrence of DLA attacks. In this study, we retrospectively evaluated a self/community-selected group of patients with lymphedema of the lower limbs with respect to the efficacy of long-acting penicillin in preventing episodes of DLA. There were no microfilariae or anti-filarial antibodies detected in the investigated group. The questions we asked were: (a) how effective is the benzathine penicillin in preventing recurrences of DLA attacks and (b) how does its long-term administration influence the bacterial spectrum of leg skin, deep tissues, lymph and lymph nodes and sensitivity to antibiotics. Two randomly selected groups of patients, receiving and not receiving penicillin during the same period of time, were compared. Evidently lower recurrence rate of DLA was observed in the treated group (p < 0.002). There was increased prevalence of cocci and gram-positive bacilli with a concomitant decrease of gram-negative bacilli on the foot and calf skin surface. Simultaneously, decreased prevalence of gram-positive cocci and gram-negative bacilli isolates in limb deep tissues and lymph was seen. No resistance to penicillin and other tested antibiotics developed in isolates from the skin surface, deep tissues and lymph. We conclude that long-lasting penicillin is effective in preventing recurrent DLA attacks.