Blood Test Screening Research Articles

An efficient randomised trial design for multi-cancer screening blood tests: nested enhanced mortality outcomes of screening trial.

Screening aims to detect cancer at an early, curable stage, and is currently recommended for breast, lung, colorectal, and cervical cancers in some countries. Prostate cancer screening might be considered for some men. Individual screening programmes for most other cancer types are unlikely to be worthwhile, mainly because each of these cancers has relatively low incidence and mortality. Leveraging external data in the design and analysis of clinical trials in neuro-oncologyIntegration of external control data, with patient-level information, in clinical trials has the potential to accelerate the development of new treatments in neuro-oncology by contextualising single-arm studies and improving decision making (eg, early stopping decisions). Based on a series of presentations at the 2020 Clinical Trials Think Tank hosted by the Society of Neuro-Oncology, we provide an overview on the use of external control data representative of the standard of care in the design and analysis of clinical trials. Full-Text PDF Basket clinical trial design for targeted therapies for cancer: a French National Authority for Health statement for health technology assessmentDuring the past decade, health technology assessment bodies have faced new challenges in establishing the benefits of new drugs for individuals and health-care systems. A topic of increasing importance to the field of oncology is the so-called agnostic regulatory approval of targeted therapies for cancer (independent of tumour location and histology) granted on the basis of basket trials. Basket trials in oncology offer the advantage of simultaneously evaluating treatments for multiple tumours, even rare cancers, in a single clinical trial. Full-Text PDF Guidelines for cellular and molecular pathology content in clinical trial protocols: the SPIRIT-Path extensionThe 2013 SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) Statement provides evidence-based recommendations for the minimum content to be included in a clinical trial protocol. Assessment of biospecimens is often required for trial eligibility or as part of an outcome evaluation, and precision molecular approaches are increasingly used in trial design. However, cellular and molecular pathology practices within trials have not been codified or formalised. We developed international consensus reporting guidelines for cellular and molecular pathology content in clinical trial protocols (the SPIRIT-Path extension) using an international Delphi process, which assesses candidate items generated from a previous systematic review, followed by an expert consensus meeting. Full-Text PDF Late phase 1 studies: concepts and outcomesOver the past two decades, targeted therapies have become cornerstone treatments for numerous cancers with oncogene addiction. Unfortunately, their effectiveness reduces over time and most patients who receive targeted therapies relapse within 12 months. The emergence of drug-resistance mechanisms in tumours paved the way for next-generation inhibitors. However, insufficient concentration of targeted therapy is a frequent but poorly explored mechanism of treatment failure. Additionally, the maximum tolerated dose (MTD) is not always reached in phase studies, and the recommended phase 2 dose is mostly based on benefit–risk ratio and pharmacokinetic considerations, which could result in a suboptimal dose. Full-Text PDF Correction to Lancet Oncol 2021; 22: 1360–62Hackshaw A, Berg CD. An efficient randomised trial design for multi-cancer screening blood tests: nested enhanced mortality outcomes of screening trial. Lancet Oncol 2021; 22: 1360–62—In this Comment the affiliation details for Christine D Berg have been updated. This correction has been made to the online version as of Nov 1, 2021. Full-Text PDF

Sociodemographic features and patterns of non-participation in colorectal cancer screening in Finland

Colorectal cancer (CRC) screening was run as a randomized health services programme in Finland between 2004 and 2016. This study evaluates sociodemographic features and patterns of non-participation among men and women invited to be screened. The study population in this register-based study includes 233 211 men and women invited to guaiac faecal occult blood test screening on consecutive screening rounds (n = 708 621 invitations). A generalized estimating equation (GEE) was used to estimate incidence rate ratios (IRR) between sociodemographic features and non-participation. The overall proportion of non-participation was 31.6% and was higher in men (38.8%) than in women (24.6%). Birth cohort, education, marital status and country of birth were associated with non-participation. The birth cohort of 1950-54 was less likely to participate than the birth cohort of 1940-44. Men and women with primary education were more likely non-participants (IRR 1.26, CI 1.23-1.29 and IRR 1.22, CI 1.18-1.26, respectively) than men or women with tertiary education. Further, unmarried persons and immigrants had an increased risk of non-participation. Initial non-participation predicted subsequent behaviour, since, e.g. ∼80% of first-round non-participants also remained non-participants in the second round. Education, gender and marital status had a significant effect on non-participation in the CRC screening programme. As high and comprehensive participation is essential for a successful screening programme, attention should be paid in ensuring participation of all sociodemographic groups. Special efforts should be invested in those not participating in the first invitational round, since initial non-participation predicts non-participation to subsequent invitations.

The quality assessment of the University hospital bone bank in Central Serbia: the second audit after fourteen years.

We analyzed the prevalence and predisposing factors for the overall rejection rate after retrieval of 267 fresh femoral head allografts over the past 7 years. The present study aimed to assess the quality system of institutional bone banking that can provide high-standard allografts with a low infection rate. Retrospective analysis of bone banking from June 2013 to December 2019 was conducted on 267 donors and 153 recipients. Of the 267 donated femoral heads, 74 were rejected, giving an overall rejection rate of 27.71%. The leading cause of allograft rejection was the inability to perform serology tests due to donor death; the absence of serological tests itself, and the donor refusal to perform the serology 6-month retest in 42 donors (15.72%). At retrieval, 12 allografts were positive, giving an overall contamination rate of 4.49%. Seven (2.62%) of the 267 allografts failed the blood screening tests. Thirteen allografts (4.86%) were discarded because of suspected damage to the packaging or disuse during surgery. An infection rate of 1.30% was found following transplantation. Over the past 7 years of bone banking, our results show that the overall rejection rate and the allograft-related infection rate correlate with international standards. The leading cause of allograft rejection was the inability to perform serology tests due to donor death and their refusal to perform the serology retests. Besides stringent aseptic allograft handling, donor motivation to participate in bone banking is extremely important for its efficient functioning.

Abstract 2610: A high performance blood test for multiple cancer early screening

Abstract Introduction: Early detection is critical to improving cancer patient survival and quality of life. Cell-free DNA (cfDNA) methylation profiling is a promising diagnostic approach for early detection of cancer, even before symptoms appear. We previously reported a non-invasive and cost-effective methylation test, Aurora, which is able to detect three major cancer types with high specificity and sensitivity especially at early stages (I/II), including lung cancer (LC), breast cancer (BC), colorectal cancer (CRC). We have improved this test to include two additional major cancer types, gastric cancer (GC) and esophageal cancer (EC). Taking together, these five cancer types represent 56% of new cancer cases and 60% of cancer-related deaths in China. Methods: We developed a novel high-throughput targeted methylation profiling platform, Aurora 2.0 (an improved version of Aurora 1.0, as presented in AACR 2020), to efficiently enrich and capture cancer-specific DNA methylation markers in plasma, prior to analysis via next-generation sequencing on a MiSeqDx system. About 100 cases each for GC and EC patients (mostly at Stage I/II), together with ~200 healthy controls, have been analyzed by using Aurora 2.0 and used for model development and validation. Results and Discussion: cfDNA methylation profiles have been obtained from 409 plasma samples, comprising 206 healthy controls, 98 GC and 105 EC patients. Logistic regression model has been developed with the Area Under Curve (AUC) of 94.0% and 93.5% for GC and EC, respectively. Overall, the performance (AUC) of Aurora 2.0 for LC/BC/CRC/GC/EC are 97.3%, 96.2%, 92%, 94% and 93.5%, respectively. An independent cohort (~2,000 plasma samples, five cancer types including lung, breast, colorectal, gastric and esophageal cancers with healthy controls) study is undergoing to further validate this test prospectively. The superior performance and cost-effectiveness (~$100) of the test could make early cancer screening of multiple major cancers in symptom-free and average-risk populations more achievable. Citation Format: Linhao Xu, Jun Wang, Weifeng Ma, Xin Liu, Ting Yang, Sihui Li, Qian Hu, Jinsheng Tao, Zhujia Ye, Zhiwei Chen, Jian-Bing Fan. A high performance blood test for multiple cancer early screening [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2610.

The Statistical Analysis of Factors Explaining the Intention of Public for Blood Donation in Jamshoro, Sindh

Purpose: The purpose of this research is to determine different factors explaining the intention of public in context of blood donation in the district of Jamshoro, Sindh.
 Methodology: The data were collected of 400 samples from four different tehsils of Jamshoro. The data was collected through well-structured questionnaire. The survey was conducted in 2019 and cluster sampling technique was used. The internal consistency of the questionnaire was examined, and Chi-Square test was applied for final analysis.
 Findings: The public's willingness to donate blood is limited, according to this study (χ2 (1) = 0.88, p=0.39). The media does not perform any significant role in awareness generating and educating the general public about the importance of donating blood (χ2 (1) = 24.35, p=0.001). Women make up a small percentage of blood donors in society (χ2 (1) = 0.05, p=0.82). This research also compares blood donors and non-donors based on gender and age. The contribution of blood donors in younger age was higher (χ2 (3) = 19.31, p=0.01) in males (χ2 (1) = 27.98, p=0.001).
 Conclusion: The awareness of blood donation was higher in males, higher education, and young age peoples (18-28) years. Furthermore, the awareness about blood donation should be made known through electronic and print media along with the educational programs at educational institutions.
 Blood bank lab assistants should be given training to keep up to date with the latest information on blood donation, samples, and screening tests.

Utility of interim blood tests for cancer screening in Li-Fraumeni syndrome.

Comprehensive annual screening reduces cancer-related mortality in Li-Fraumeni syndrome (LFS), a cancer-prone disorder caused by pathogenic germline TP53 variants. Blood tests at months 4 and 8 between annual screening are recommended but their effectiveness in early cancer detection has not been established. Interim blood counts and inflammatory biomarkers were evaluated in 132 individuals with LFS (112 adults, 87 female, median age 36years [range 3-68], median follow-up 37months [range 2-70]) and test abnormalities were observed in 225 (35%). Thirteen cancers in 12 individuals were diagnosed between annual screenings but only one cancer (colorectal adenocarcinoma) was diagnosed due to an abnormal interim blood test. Fisher's exact test and generalized estimating equation models found no statistical associations between cancer diagnoses and any test abnormality. Four- and 8-monthly interim screening blood tests may not be of independent benefit for cancer detection in LFS, but annual cancer screening and personalized follow-up remain essential.

ID: 3521534 MAJORITY OF INDIVIDUALS WHO HAVE DECLINED COLONOSCOPY AND STOOL TEST ARE WILLING TO UNDERGO BLOOD TEST FOR CRC SCREENING

One-third of Americans between age 50 and 75 years are not up to date with colorectal cancer (CRC) screening. Barriers to colonoscopy and stool-based testing have led to ongoing interest in blood-based screening tests. As part of a clinical trial assessing the impact of offering a Septin9 blood test for CRC screening in individuals who’ve previously declined colonoscopy and fecal immunochemical testing (FIT), we conducted a questionnaire to understand patient perspectives on different CRC screening methods.

P012 Raynaud's phenomenon: a primary care problem?

Abstract Background/Aims Despite an established awareness of Raynaud’s phenomenon (RP), defined as an episodic vasospasm of the arteries in the extremities, no studies have yet described the way in which the phenomenon is assessed and managed within a primary care setting. The primary aim of this study is to evaluate the way in which Raynaud’s Phenomenon commonly presents, is investigated, and managed within a UK general practice (GP); auditing concordance with the National Institute for Health and Care Excellence (NICE) Clinical Knowledge Summary (CKS) 2020 guidance. Methods An audit of 79 patients with a coded diagnosis of RP was completed at Green Lane Medical Centre, a Merseyside General Practice. Patient care was audited against standards within the NICE CKS. Results The patient group was comprised of 53 females (67.1%) and 26 males (32.9%). 89.9% (71/79) of patients have a working diagnosis of primary RP. Patient age at the time of audit: 4% aged 0-18; 29% aged 19-45; 30% aged 46-60; 37% aged 60+. 59.5% (47/79) of patients had 2 or more troubling symptoms of RP documented by their GP, with 12.7% (10/79) describing a classic triphasic colour change. Examination findings were documented for 55.7% (44/79) of patients and 27.9% (22/79) received an autoantibody screen. 26.6% (21/79) of patients were referred to secondary care, with 42.9% (9/21) of these referrals specifying an intention to rule out Secondary RP. Documentation available regarding patient management indicated that conservative advice was provided to 62.5% (40/64) of patients, the most common being a patient information sheet (26/64). Medical management was offered to 39.1% (25/64) of patients but was declined by 24.0% (6/25) of those to whom it was offered, with most (16/19) patients who were commenced on medical therapy discontinuing by the time of audit. In secondary care, 81.0% (17/21) of referred patients had further investigations, 57.1% (12/21) received reassurance before or after the investigations and conservative advice was the most common management. Conclusion This study suggests that GPs play a major role in the assessment and management of patients with RP; 73.4% (58/79) of patients were not referred to secondary care. Of those that were referred, the majority were due to worsening or severe symptoms, or suspected secondary RP, in line with the CKS guidance. Most patients present with 2 or more of the symptoms described in the NICE CKS guidance and the use of examination and screening blood tests in primary care appears to be the mainstay of assessment. In accordance with the CKS guidance, most patients are provided with information and lifestyle advice. High rates of medical therapy discontinuation suggest that assessment of severity of symptoms and improved patient education of medication side effects may play a role in determining the most appropriate candidates for medical therapy. Disclosure K.E. Winstone: None. M.E. Anderson: None. A.E. Stickland: None.

Issue Highlights

Issue Highlights

Over-use of thyroid testing in Canadian and UK primary care in frequent attenders: A cross-sectional study.

Thyroid-stimulating hormone (TSH) is a common test used to detect and monitor clinically significant hypo- and hyperthyroidism. Population-based screening of asymptomatic adults for thyroid disorders is not recommended. The research objectives were to determine patterns of TSH testing in Canadian and English primary care practices, as well as patient and physician practice characteristics associated with testing TSH for primary care patients with no identifiable indication. In this 2-year cross-sectional observational study, Canadian and English electronic medical record databases were used to identify patients and physician practices. Cohorts of patients aged 18years or older, without identifiable indications for TSH testing, were generated from these databases. Analyses were performed using a random-effects logistic regression to determine patient and physician practice characteristics associated with increased testing. We determined the proportion of TSH tests performed concurrently with at least one common screening blood test (lipid profile or hemoglobin A1c). Standardised proportions of TSH test per family practice were used to examine the heterogeneity in the populations. At least one TSH test was performed in 35.97% (N=489663) of Canadian patients and 29.36% (N=1030489) of English patients. Almost all TSH tests in Canada and England (95.69% and 99.23% respectively) were within the normal range (0.40-5.00mU/L). A greater number of patient-physician encounters was the strongest predictor of TSH testing. It was determined that 51.40% of TSH tests in Canada and 76.55% in England were performed on the same day as at least one other screening blood test. There was no association between the practice size and proportion of asymptomatic patients tested. This comparative binational study found TSH patterns suggestive of over-testing and potentially thyroid disorder screening in both countries. There may be significant opportunities to improve the appropriateness of TSH ordering in Canada and England and therefore improve the allocation of limited system resources.

Microbiome Analysis of More Than 2,000 NHS Bowel Cancer Screening Programme Samples Shows the Potential to Improve Screening Accuracy.

There is potential for fecal microbiome profiling to improve colorectal cancer screening. This has been demonstrated by research studies, but it has not been quantified at scale using samples collected and processed routinely by a national screening program. Between 2016 and 2019, the largest of the NHS Bowel Cancer Screening Programme hubs prospectively collected processed guaiac fecal occult blood test (gFOBT) samples with subsequent colonoscopy outcomes: blood-negative [n = 491 (22%)]; colorectal cancer [n = 430 (19%)]; adenoma [n = 665 (30%)]; colonoscopy-normal [n = 300 (13%)]; nonneoplastic [n = 366 (16%)]. Samples were transported and stored at room temperature. DNA underwent 16S rRNA gene V4 amplicon sequencing. Taxonomic profiling was performed to provide features for classification via random forests (RF). Samples provided 16S amplicon-based microbial profiles, which confirmed previously described colorectal cancer-microbiome associations. Microbiome-based RF models showed potential as a first-tier screen, distinguishing colorectal cancer or neoplasm (colorectal cancer or adenoma) from blood-negative with AUC 0.86 (0.82-0.89) and AUC 0.78 (0.74-0.82), respectively. Microbiome-based models also showed potential as a second-tier screen, distinguishing from among gFOBT blood-positive samples, colorectal cancer or neoplasm from colonoscopy-normal with AUC 0.79 (0.74-0.83) and AUC 0.73 (0.68-0.77), respectively. Models remained robust when restricted to 15 taxa, and performed similarly during external validation with metagenomic datasets. Microbiome features can be assessed using gFOBT samples collected and processed routinely by a national colorectal cancer screening program to improve accuracy as a first- or second-tier screen. The models required as few as 15 taxa, raising the potential of an inexpensive qPCR test. This could reduce the number of colonoscopies in countries that use fecal occult blood test screening.

How do I create a partnership between a blood bank and a milk bank to provide safe, pasteurized human milk to infants?

The now 5-year collaboration between the Indiana Blood Center, now Versiti Blood Center of Indiana, and The Milk Bank has increased the number of human milk donors, improved the collection and processing of donor milk, and improved awareness of this lifesaving resource. The Indiana Blood Center provides greater visibility for The Milk Bank, creating more opportunities to reach potential donors, and can provide the screening blood test for potential donors to become approved human milk donors. The resources of the multiple locations of the Indiana Blood Center permitted the formation of new milk depots in five different cities and quicker transportation of donated milk through their active courier system. This partnership most importantly has improved awareness for both lifesaving missions to the communities they serve.

Real-world cost-effectiveness of stool-based colorectal cancer screening in a Medicare population

Aim Multiple screening strategies are guideline-endorsed for average-risk colorectal cancer (CRC). The impact of real-world adherence rates on the cost-effectiveness of non-invasive stool-based CRC screening strategies remains undefined. Methods This cost-effectiveness analysis from the perspective of Medicare as a primary payer used the Colorectal Cancer and Adenoma Incidence and Mortality Microsimulation Model (CRC–AIM) to estimate cost and clinical outcomes for triennial multi-target stool DNA (mt-sDNA), annual fecal immunochemical test (FIT) and annual fecal occult blood test (FOBT) screening strategies in a simulated cohort of US adults aged 65 years, who were assumed to either be previously unscreened or initiating screening upon entry to Medicare. Reported real-world adherence rates for initial stool-based screening and colonoscopy follow up (after a positive stool test result) were defined as 71.1% and 73.0% for mt-sDNA, 42.6% and 47.0% for FIT, and 33.4% and 47.0% for FOBT, respectively. The incremental cost-effectiveness ratio using quality-adjusted life years (QALY) was defined as the primary outcome of interest; other cost and clinical outcomes were also reported in secondary analyses. Multiple sensitivity and scenario analyses were conducted. Results When reported real-world adherence rates were included only for initial stool-based screening, mt-sDNA was cost-effective versus FIT ($62,814/QALY) and FOBT ($39,171/QALY); mt-sDNA also yielded improved clinical outcomes. When reported real-world adherence rates were included for both initial stool-based screening and follow-up colonoscopy (when indicated), mt-sDNA was increasingly cost-effective compared to FIT and FOBT ($31,725/QALY and $28,465/QALY, respectively), with further improved clinical outcomes. Limitations Results are based on real-world cross-sectional adherence rates and may vary in the context of other types of settings. Only guideline-recommended stool-based strategies were considered in this analysis. Conclusion Comparisons of the effectiveness and benefits of specific CRC screening strategies should include both test-specific performance characteristics and real-world adherence to screening tests and, when indicated, follow-up colonoscopy.

Post-bariatric surgery nutritional follow-up in primary care: a population-based cohort study.

BackgroundBariatric surgery is the most effective treatment for severe obesity. However, without recommended follow-up it has long-term risks.AimTo investigate whether nutritional and weight monitoring in primary care meets current clinical guidance, after patients are discharged from specialist bariatric care.Design and settingRetrospective cohort study in primary care practices contributing to IQVIA Medical Research Data in the UK (1 January 2000 to 17 January 2018).MethodParticipants were adults who had had bariatric surgery with a minimum of 3 years’ follow-up post-surgery, as this study focused on patients discharged from specialist care (at 2 years post-surgery). Outcomes were the annual proportion of patients from 2 years post-surgery with a record of recommended nutritional screening blood tests, weight measurement, and prescription of nutritional supplements, and the proportions with nutritional deficiencies based on blood tests.ResultsA total of 3137 participants were included in the study, and median follow-up post-surgery was 5.7 (4.2–7.6) years. Between 45% and 59% of these patients had an annual weight measurement. The greatest proportions of patients with a record of annual nutritional blood tests were for tests routinely conducted in primary care, for example, recorded haemoglobin measurement varied between 44.9% (n = 629/1400) and 61.2% (n = 653/1067). Annual proportions of blood tests specific to bariatric surgery were low, for example, recorded copper measurement varied between 1.2% (n = 10/818) and 1.5% (n = 16/1067) where recommended. Results indicated that the most common deficiency was anaemia. Annual proportions of patients with prescriptions for recommended nutritional supplements were low.ConclusionThis study suggests that patients who have bariatric surgery are not receiving the recommended nutritional monitoring after discharge from specialist care. GPs and patients should be supported to engage with follow-up care. Future research should aim to understand the reasons underpinning these findings.

Abstract 16738: Association Between First and Second Trimester Maternal Screening Biochemistry, Ultrasound, and Fetal Brain Growth in Presence of Fetal or Maternal Congenital Heart Disease

Introduction: Newer research has highlighted significant neurological impairments in children and adults with congenital heart disease (CHD). The more severe the heart defect, the higher the neurologic impairment. Pregnancies complicated by fetal or maternal CHD carry a higher risk of placental abnormalities. We studied the association between pregnancy hormonal levels and fetal head and body growth. Hypothesis: Placental dysfunction in pregnancies with fetal or maternal CHD alters pregnancy hormonal levels affecting fetal brain and somatic growth. Methods: We performed a retrospective case-control study on pregnant women (year 2010-2019) at the University of Iowa. Only women with first and/or second trimester prenatal screening (ultrasound and blood test) were included. Pregnancies with fetal chromosomal abnormalities, multiple gestation, maternal diabetes, smoking, or hypertension were excluded. Pregnancies were either healthy controls (n=36), women with CHD (MCHD; n=26), or fetus with CHD (FCHD; n=23). Pregnancy hormonal levels, ultrasound findings, and fetal/neonatal growth percentiles and/or z-scores data were analyzed. Results: Women with CHD were younger (p=0.004) with increased fetal nuchal translucency (p=0.003) compared to controls. Women in MCHD (p=0.02) and FCHD (p=0.02) group delivered earlier than controls. FCHD had significantly lower pregnancy associated plasma protein-A (PAPP-A) levels than controls (p=0.04). The groups had no difference in the second trimester fetal head circumference (HC) and femur length. FCHD group had significantly smaller HC percentile (p=0.03) and z-scores (p=0.03) at birth than controls. Both FCHD and MCHD had smaller birth weight and length compared to controls. However, only FCHD group demonstrated significantly lower HC to birth weight ratio (p=0.01). The controls had a positive correlation between human chorionic gonadotropin level and head circumference z-score at birth (r=0.34;p=0.053). Conclusions: Pregnant women with CHD have increased fetal nuchal translucency and deliver at earlier gestational age. Women with fetal CHD have smaller neonatal head and body size at birth with associated low PAPP-A level early in their pregnancy probably related to placental dysfunction.

Cluster randomized controlled trial of volitional and motivational interventions to improve bowel cancer screening uptake: A population-level study.

Colorectal cancer (CRC) is a leading cause of cancer death worldwide, although effective uptake of bowel cancer screening is below 60% in England. This trial investigated the influence of volitional and motivational interventions and their combination on increasing guaiac fecal occult blood testing (gFOBT) screening uptake. In total, 34,633 participants were recruited (via North-East of England bowel cancer screening hub) into a 2×2 factorial cluster randomized controlled trial. Social norm-based motivational intervention (SNA); Implementation intention-based Volitional Help Sheet (VHS); Combined intervention (SNA+VHS); Treatment as usual control. Screening rate (gFOBT kit return rate within 8 weeks of invitation) was the primary outcome. Screening kits were returned by 60% of participants (N=20,847/34,633). A substantial imbalance was observed in participant characteristics, participants in the combined intervention group were younger and more likely to be first time invitees. Adjusted analyses found insufficient evidence that any of the interventions were different to control (Combined: OR = 1.18, 95% CI 0.97-1.44; SNA alone: OR=0.93; 95% CI: 0.76-1.15; VHS alone OR= 0.88; 95% CI: 0.75-1.03). Subgroup analyses demonstrated a significant beneficial effect of the combined intervention in the youngest age group compared to control (OR = 1.27; 95% CI: 1.05-1.54). The study did not support any benefit of either VHS or SNA interventions alone on bowel cancer screening uptake. The combined SNA+VHS intervention was significantly different from control only in the youngest age group in adjusted analyses. However, the magnitude of effect in the youngest age group suggests that further testing of VHS plus SNA interventions in carefully targeted populations may be warranted.

Association between faecal occult bleeding and medicines prescribed for chronic disease: a data linkage study

AimsThe presence of detectable faecal haemoglobin (f-Hb) has been shown to be associated with all-cause mortality and with death from a number of chronic diseases not known to cause gastrointestinal...

False positive antigen test for Dirofilaria immitis after heat treatment of the blood sample in a microfilaremic dog infected with Acanthocheilonema dracunculoides

BackgroundDirofilaria immitis is responsible for heartworm disease in dogs in endemic areas worldwide. Screening for this infection is done by blood tests. Antigen testing is the most sensitive method to detect an infection with adult (female) worms. Microscopic examination of a blood smear or Knott’s test can be used to detect circulating microfilariae, the infective larvae. To increase the sensitivity of the antigen test by decreasing the false negative test results, heating of the blood sample has been recommended in recent guidelines. Heating is believed to remove blocking immune-complexes. Circulating microfilariae are not specific findings for heartworm infection, as other nematodes (among others, Acanthocheilonema dracunculoides) can also result in microfilaremia. Although the type of microfilariae cannot be determined by microscopy alone, real-time PCR can reliably identify the infecting nematode species. Correct identification of the parasite is of major importance, as an infection with D. immitis requires antiparasitic therapy, whereas A. dracunculoides is thought to be a clinically irrelevant coincidental finding. The present case report describes a microfilaremic dog where the initial antigen test for D. immitis turned positive after heat treatment, whereas real-time PCR revealed that the microfilariae were A. dracunculoides (syn. Dipetalonema dracunculoides).ResultsA circa 5-year old, asymptomatic Spanish mastiff dog was referred for heartworm therapy because microfilariae were found via a screening blood test. The dog was recently imported to the Netherlands from Spain, where it had been a stray dog. Antigen tests on a plasma sample for D. immitis were performed with three different test kits, which all turned out to be negative. However, heat treatment of two of these samples were carried out and both of them led to a positive antigen test result. Real-time PCR showed that the circulating microfilariae belonged to A. dracunculoides species. Three administrations of moxidectin spot-on at monthly intervals resulted in a negative antigen and a negative Knott’s tests one month after the last treatment.ConclusionsWe conclude that heat treatment of initially negative blood samples for D. immitis could lead to false positive antigen test results if the dog is infected with A. dracunculoides.

S0276 Can iFOBT (Immunochemical Faecal Occult Blood Test) for Bowel Cancer Screening Be Safely Deferred for Five Years After a Colonoscopy?

INTRODUCTION: Australian and international guidelines suggest that immunochemical faecal occult blood test (iFOBT) for colorectal cancer (CRC) screening may be deferred for 5–10 years after a negative colonoscopy. The aim of this retrospective multicentre observational study was to evaluate the outcomes of patients who had a repeat colonoscopy for iFOBT positivity within five years of a previous colonoscopy showing low risk or normal findings, to assess the risk of interval CRC and advanced colorectal neoplasia (ACRN). We sought to determine if having a prior colonoscopy with normal or low risk findings within the last five years would predict for negative findings on a repeat colonoscopy in asymptomatic patients who were iFOBT positive. METHODS: We retrospectively identified patients who underwent a repeat colonoscopy for iFOBT positivity within five years of a previous colonoscopy showing normal or low risk findings from November 2016 to November 2018. Patients identified from Provation, Auscare and the Viewer databases were included from four sites, including The Prince Charles Hospital in Brisbane, Cairns Base Hospital, Innisfail Hospital and Atherton District Hospital in Northern Queensland. We excluded patients with a past history of CRC, patients with a familial malignancy syndrome, patients with poor bowel preparation and patients who were symptomatic. RESULTS: Among 3,795 patients who underwent colonoscopy for a positive iFOBT in the study period, 239 had a previous colonoscopy in the five-year window that met inclusion criteria. Of these, 4 (1.7%) patients had locally advanced CRC at two regional sites, and 19 (7.9%) patients had ACRN. 42 (17.6%) patients had high risk adenoma, 21 (8.8%) patients had sessile serrated adenoma and 87 (36.4%) patients had adenoma of various sizes. Inadequate bowel preparation in the previous colonoscopy was associated with the findings of subsequent high-risk adenomas and CRC. CONCLUSION: Our study observed that a substantial portion of patients have interval ACRN associated with a positive iFOBT performed outside of guidelines. These finding were not uniform between the study sites and may reflect local differences, highlighting the importance of interpretation of guidelines, the ability of the clinician to override guidelines if clinically indicated, the need for colonoscopy care standards and teamwork that may facilitate excellence in practice.

Human babesiosis: recent advances and future challenges.

As human babesiosis caused by apicomplexan parasites of the Babesia genus is associated with transfusion-transmitted illness and relapsing disease in immunosuppressed populations, it is important to report novel findings relating to parasite biology that may be responsible for such pathology. Blood screening tools recently licensed by the FDA are also described to allow understanding of their impact on keeping the blood supply well tolerated. Reports of tick-borne cases within new geographical regions such as the Pacific Northwest of the USA, through Eastern Europe and into China are also on the rise. Novel features of the parasite lifecycle that underlie the basis of parasite persistence have recently been characterized. These merit consideration in deployment of both detection, treatment and mitigation tools such as pathogen inactivation technology. The impact of new blood donor screening tests in reducing transfusion transmitted babesiosis is discussed. New Babesia species have been identified globally, suggesting that the epidemiology of this disease is rapidly changing, making it clear that human babesiosis is a serious public health concern that requires close monitoring and effective intervention measures. Unlike other erythrocytic parasites, Babesia exploits unconventional lifecycle strategies that permit host cycles of different lengths to ensure survival in hostile environments. With the licensure of new blood screening tests, incidence of transfusion transmission babesiosis has decreased.