Screening Asymptomatic Patients Research Articles

Challenges around diagnosis of early onset colorectal cancer, and the case for screening.

Colorectal cancer (CRC) is the third most diagnosed cancer in the world, with an estimated 1.93 million cases diagnosed in 2020. While the overall CRC incidence in many countries is falling there has been a dramatic increase in CRC in those aged under 50 (early onset colorectal cancer, EOCRC). The reason for this increase in EOCRC is unknown. As the best predictor of survival is stage at diagnosis, early diagnosis is likely to be beneficial and population screening may facilitate this. A narrative review of the literature was undertaken. Improving time to diagnosis in symptomatic patients is beneficial. However, by the time symptoms develop, over a third of patients already have metastatic disease. Screening asymptomatic patients (with Faecal Immunochemical test (FIT) and colonoscopy) has been proved to be effective in older patients (>60 years). In younger populations, the decreasing incidence rates of CRC previously made cost effectiveness, compliance and therefore benefit questionable. Now, with the increasing incidence of CRC in those under 50 years of age, modelling suggests screening with FIT and colonoscopy is cost effective from 40 years of age. There is evidence that some countries screening below 50 have prevented the rise in EOCRC incidence. Additionally the use of new and novel non-invasive biomarkers may also be able to improve the accuracy of screening asymptomatic patients. Diagnosis of EOCRC once symptoms develop is often too late, and screening patients from age 40 is the best way to improve outcomes in this group.

Shifting Grounds-Facilitating Self-Care in Testing for Sexually Transmitted Infections Through the Use of Self-Test Technology: Qualitative Study.

Chlamydia remains prevalent worldwide and is considered a global public health problem. However, testing rates among young sexually active people remain low. Effective clinical management relies on screening asymptomatic patients. However, attending face-to-face consultations of testing for sexually transmitted infections is associated with stigmatization and anxiety. Self-testing technology (STT) allows patients to test themselves for chlamydia and gonorrhea without the presence of health care professionals. This may result in wider access to testing and increase testing uptake. Therefore, the sexual health clinic at Odense University Hospital has designed and developed a technology that allows patients to get tested at the clinic through self-collected sampling without a face-to-face consultation. This study aimed to (1) pilot-test STT used in clinical practice and (2) investigate the experiences of patients who have completed a self-test for chlamydia and gonorrhea. The study was conducted as a qualitative study inspired by the methodology of participatory design. Ethnographic methods were applied in the feasibility study and the data analyzed were inspired by the action research spiral in iterative processes using steps, such as plan, act, observe, and reflect. The qualitative evaluation study used semistructured interviews and data were analyzed using a qualitative 3-level analytical model. The findings from the feasibility study, such as lack of signposting and adequate information, led to the final modifications of the self-test technology and made it possible to implement it in clinical practice. The qualitative evaluation study found that self-testing was seen as more appealing than testing at a face-to-face consultation because it was an easy solution that both saved time and allowed for the freedom to plan the visit independently. Security was experienced when the instructions balanced between being detail-oriented while also being simple and illustrative. The anonymity and discretion contributed to preserving privacy and removed the fear of an awkward conversation or being judged by health care professionals thus leading to the reduction of intrusive feelings. Accessible health care services are crucial in preventing and reducing the impact of sexually transmitted infections and STT may have the potential to increase testing uptake as it takes into account some of the barriers that exist. The pilot test and evaluation have resulted in a fully functioning implementation of STT in clinical practice.

Diagnosis and management of blunt cerebrovascular injuries: What you need to know.

Blunt cerebrovascular injuries are not as rare as they were once thought to be-but they still have the same potential for disastrous outcomes. They may occur following any trauma, but more common with higher energy transfer mechanisms. If stroke occurs, prompt recognition and treatment offers the best chance for optimal outcome. Early diagnosis and provision of antithrombotic therapy may prevent strokes, so screening of asymptomatic patients is recommended. Herein we will present what you need to know to diagnose and manage blunt cerebrovascular injury.

SARS-CoV-2 RT-PCR as a universal screening on planned admission in asymptomatic patients

Universal screening for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on admission is reportedly beneficial in preventing nosocomial infections. However, some issues remain, including low positivity rate, cost, and time required for testing. We describe SARS-CoV-2 reverse transcription polymerase chain reaction (PCR) for universal screening in asymptomatic patients on planned admissions. In total, 14,574 patients were included between October 12, 2020, and June 23, 2022. The PCR-positive rate for the period was 0.44 % (64/14,574). The PCR positivity for the epidemic period by strain was 0.28 % (95 % confidence interval [CI] 0.12–0.56 %), 0.16 % (95 % CI 0.05–0.37 %), 0.21 % (95 % CI 0.09–0.41 %), and 0.9 % (95 % CI 0.65–1.2 %) for the wild-type strain, Alpha, Delta, and Omicron variants, respectively. The proportion of Ct values < 30 was higher in the first half of the epidemic (first vs. second, 29.4 % [95 % CI 16.9–44.8 %] vs. 16.7 % [95 % CI 6.0–28.5 %]), whereas that of Ct values ≥ 35 increased significantly in the second half (first vs. second, 32.4 % [95 % CI 19.3–47.8 %] vs. 70.0 % [95 % CI 53.5–83.4 %]). Of all positives, 50 % (32/64) had a coronavirus disease (COVID-19) history before PCR screening, with a median of 28 days (10–105) from COVID-19 onset or positive to PCR screening. PCR screening may help detect positives with high viral loads early in the epidemic for each mutant strain, with an increasing proportion of positives with low viral loads later in the epidemic. PCR testing may be unnecessary for recently diagnosed cases and patients in whom reinfection is unlikely.

213. Do Patients with Candidemia Need an Ophthalmology Exam?

Abstract Background Candidemia can lead to hematogenous seeding of the eye resulting in chorioretinitis or endophthalmitis. IDSA recommends a screening dilated retinal examination for patients with candidemia, whilst American Academy of Ophthalmology (AAO) recently declared this a low value practice. Using an inter-disciplinary team, we evaluated ophthalmology examination for patients with candidemia. Methods We performed a retrospective study of patients with candidemia at an academic medical center and affiliated hospitals between January 2011 – June 2022. Electronic medical records were reviewed for demographics and baseline characteristics. The primary outcome was chorioretinitis and/or endophthalmitis. The study was adjudicated by independent review from infectious disease and ophthalmology providers. Results We included 308 patients with a blood culture positive for candida species. 149 patients (48%) received an ophthalmologic exam, of which 55% (82) were asymptomatic. Abnormal ocular findings concerning for presumed ocular candida complications were found in 12 patients (8%, 12/149), of which 4 had alternative diagnoses to candida choriorentinits or endophthalmitis. All of the remaining 8 patients (5%, 8/149) had presumed candida chorioretinitis with no cases of candida endophthalmitis and this led to a change in management in 88% (7/8) of patients (Table 1). Of the 8 patients, 3 patients were asymptomatic, making the number needed to screen 28 to detect presumed candida chorioretinitis amongst asymptomatic patients. We did not identify statistically significant risk factors for development of abnormal ocular findings (Table 2). Table 1 Clinical diagnosis and management of patients with candida chorioretinitis and/or endophthalmitis Table 2 Clinical features of patients with and without ocular candidiasis Conclusion IDSA and AAO recommend ophthalmologic examination in symptomatic and intubated patients with candidemia. We found a 5% incidence of presumed ocular candidiasis in patients with candidemia. Given the limitations of our study, we could not conclude for or against screening in asymptomatic patients as this did not lead to a significant change in patient outcomes. Inter-disciplinary decisions involving ophthalmology and infectious diseases can help inform best practices for screening in asymptomatic patients. Future studies should evaluate ocular photography and teleophthalmology as screening strategies. Disclosures All Authors: No reported disclosures

Symposium 4

Extra-articular manifestations are common in Rheumatoid-arthritis (RA), involving the skin, eyes, heart, and lung, causing significant comorbidities. In particular, clinically significant rheumatoid arthritis-associated interstitial lung disease (RA-ILD) has a prevalence of about 10%-19% among RA patients. However, the exact prevalence of ILD in RA patients is not well known and there is also a lack of local data in Hong Kong. Early screening and identification of ILD in RA patients is important for improving patient outcomes. Currently, there is no established algorithm for screening in asymptomatic patients with RA. High resolution computed tomography (HRCT) is a standard assessment in ILD diagnosis but is associated with high cost. Pulmonary function test and lung ultrasound might also be useful in identifying ILD. Besides, multiple clinical risk factors and novel biomarkers have been explored for early identification of RA-ILD. To evaluate the usefulness of these predictors and to evaluate the burden of interstitial lung disease (ILD) among patients with RA, a local study (RAISE, Rheumatoid Arthritis-associated ILD: Screening and Evaluation in high-risk patients) was designed in Hong Kong to assess the prevalence of RA-ILD among RA patients with high risk, and to identify potential clinical and biochemical markers associated with the condition. In this session, Dr. Shirley Chan will share the protocol of the RAISE study and the screening approach. The interim results will also be analyzed and presented.

Survey of Retina Specialists’ Attitudes and Practice Patterns of Screening and Management of Candida Endophthalmitis

ABSTRACT Purpose To understand retina specialists’ attitudes and practice patterns for screening for and managing Candida endophthalmitis and any impact of the COVID-19 pandemic on these practice patterns. Methods A survey was developed on Survey Monkey and distributed to ASRS regular members via email in April 2021. Results The survey had 231 respondents, of whom 169 (73%) performed inpatient consultations. Ninety percent responded that they do not recommend routinely screening asymptomatic patients with candidemia. For unresponsive patients with candidemia that lack visible signs of endophthalmitis, 65% did not recommend routine screening. However, 85% reported their affiliated hospitals did not have a policy to defer such screening consultations; this proportion did not significantly change when asked if a policy was implemented in response to the COVID-19 pandemic. For patients with a dilated examination without signs of endophthalmitis, 89% surveyed recommended continuing systemic antifungals and reconsult PRN, while the remainder recommended repeat examinations until off antifungals. For initial management of Candida endophthalmitis, 55% indicated systemic antifungals only; 43% indicated systemic antifungals with tap & inject, and 2% indicated systemic antifungals with vitrectomy and intravitreal antifungals. Conclusion A discordance exists between the prevailing opinion among retina specialists against routine Candida endophthalmitis screening and hospital consultation policies, which were not significantly impacted by the COVID-19 pandemic. In cases of diagnosed endogenous endophthalmitis, slightly more than half of surveyed retina specialists would not initiate additional treatment beyond systemic antifungals while just under half surveyed recommended initial tap and inject in addition to systemic antifungals.

Prevalence of tissue transglutaminase antibodies and IgA deficiency are not increased in juvenile idiopathic arthritis: a case-control study

BackgroundThe prevalence of Celiac Disease (CD) in Juvenile Idiopathic Arthritis (JIA) has been reported to be 0.1–7% in various small studies. As a result of the limited number of research and their inconclusive results there are no clear recommendations for routine CD screening in asymptomatic patients with JIA. Our aim is to estimate the prevalence of IgA deficiency and tissue transglutaminase (tTG) IgA in a cohort of JIA followed in two large academic medical centers.MethodsSerum was collected and stored from all subjects and analyzed in a reference laboratory for total IgA (Quantitative Nephelometry) and tTG IgA antibody levels (Semi-Quantitative Enzyme-Linked Immunosorbent Assay). Fisher’s exact tests were performed for statistical significance. Risk estimates (odds ratios) with 95% confidence intervals were calculated.Results808 JIA cases and 140 controls were analyzed. Majority were non-Hispanic whites (72% vs. 68% p = 0.309). A total of 1.2% of cases were IgA deficient compared to none of the controls (p = 0.373). After excluding IgA deficient subjects, 2% of cases had tTG IgA ≥ 4u/mL compared to 3.6% of controls (p = 0.216) (OR = 0.5; 95% C.I = 0.1–1.4); and 0.8% of cases had tTG IgA > 10u/mL compared to 1.4% of controls (p = 0.627) (OR = 0.5; 95%C.I = 0.1–2.9).ConclusionsUsing the largest JIA cohort to date to investigate prevalence of celiac antibodies, the prevalence of positive tTG IgA was 0.8% and of IgA deficiency was 1.2%. The results did not demonstrate a higher prevalence of abnormal tTG IgA in JIA. The study did not support the routine screening of asymptomatic JIA patients for CD.

Screening asymptomatic patients post PCI with myocardial perfusion imaging

Screening asymptomatic patients post PCI with myocardial perfusion imaging

Predictors of graft failure after first detection of de novo donor-specific HLA antibodies in kidney transplant recipients.

De novo donor-specific antibodies (dnDSAs) may cause antibody-mediated rejection and graft dysfunction. Little is known about the clinical course after first detection of dnDSAs during screening in asymptomatic patients. We aimed to assess the value of estimated glomerular filtration rate (eGFR) and proteinuria to predict graft failure in patients with dnDSAs and their potential utility as surrogate endpoints. All 400 kidney transplant recipients with dnDSAs at our centre (1 March 2000-31 May 2021) were included in this retrospective study. The dates of graft loss, rejection, doubling of creatinine, ≥30% eGFR decline, proteinuria ≥500mg/g and ≥1000mg/g were registered from the first dnDSA appearance. During 8.3years of follow-up, graft failure occurred in 33.3% of patients. Baseline eGFR and proteinuria correlated with 5-year graft loss (area under the receiver operating characteristics curve 0.75 and 0.80, P<.001). Creatinine doubled after a median of 2.8years [interquartile range (IQR) 1.5-5.0] from dnDSA and the time from doubling creatinine to graft failure was 1.0year (IQR 0.4-2.9). Analysing eGFR reduction ≥30% as a surrogate endpoint (148/400), the time from dnDSA to this event was 2.0years (IQR 0.6-4.2), with a positive predictive value (PPV) of 45.9% to predict graft loss, which occurred after 2.0years (IQR 0.8-3.2). The median time from proteinuria ≥500mg/g and ≥1000mg/g to graft failure was identical, 1.8years, with a PPV of 43.8% and 49.0%, respectively. Composite endpoints did not improve PPV. Multivariable analysis showed that rejection was the most important independent risk factor for all renal endpoints and graft loss. Renal function, proteinuria and rejection are strongly associated with graft failure in patients with dnDSA and may serve as surrogate endpoints.

Rethinking coronary heart disease tests in pretransplant evaluation: Cardiologists no longer screen asymptomatic patients for coronary artery disease—so why are transplant centers still doing it?

Rethinking coronary heart disease tests in pretransplant evaluation: Cardiologists no longer screen asymptomatic patients for coronary artery disease—so why are transplant centers still doing it?

SARS-CoV-2 Testing of Emergency Department Patients Using cobas® Liat® and eazyplex® Rapid Molecular Assays.

Rapid testing for Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) of patients presenting to emergency departments (EDs) facilitates the decision for isolation on admission to hospital wards. Differences in the sensitivity of molecular assays have implications for diagnostic workflows. This study evaluated the performance of the cobas® Liat® RT-PCR, which is routinely used as the initial test for ED patients in our hospitals, compared with the eazyplex® RT-LAMP. A total of 378 oropharyngeal and nasal swabs with positive Liat® results were analysed. Residual sample aliquots were tested using NeuMoDx™, cobas® RT-PCR, and the eazyplex® assay. Patients were divided into asymptomatic (n = 157) and symptomatic (n = 221) groups according to the WHO case definition. Overall, 14% of positive Liat® results were not confirmed by RT-PCR. These samples were mainly attributed to 26.8% of asymptomatic patients, compared to 3.8% of the symptomatic group. Therefore, positive Liat® results were used to provisionally isolate patients in the ED until RT-PCR results were available. The eazyplex® assay identified 62% and 90.6% of RT-PCR-confirmed cases in asymptomatic and symptomatic patients, respectively. False-negative eazyplex® results were associated with RT-PCR Ct values > 30, and were more frequent in the asymptomatic group than in the symptomatic group (38.1% vs. 5.1%, respectively). Both the Liat® and eazyplex® assays are suitable for testing symptomatic patients. Their use in screening asymptomatic patients depends on the need to exclude any infection or identify those at high risk of transmission.

Performance of the 2019 ESC/EASD guideline strategy for the screening of silent coronary artery disease in patients with diabetes

BackgroundThe 2019 guidelines for cardiovascular risk stratification by the European Society of Cardiology and European Association for the Study of Diabetes (ESC-EASD) suggested screening for silent coronary disease in very high risk patients with severe target organ damage (TOD) (i.e. peripheral occlusive arterial disease or severe nephropathy) or high coronary artery calcium (CAC) score. This study aimed to test the validity of this strategy.MethodsIn this retrospective study, we included 385 asymptomatic patients with diabetes and no history of coronary disease but with TOD or ≥ 3 risk factors in addition to diabetes. CAC score was measured using computed tomography scan and a stress myocardial scintigraphy was performed to detect silent myocardial ischemia (SMI), with subsequent coronary angiography in those with SMI. Various strategies to select patients to be screened for SMI were tested.ResultsCAC score was ≥ 100 Agatston units (AU) in 175 patients (45.5%). SMI was present in 39 patients (10.1%) and among the 30 patients who underwent angiography, 15 had coronary stenoses and 12 had a revascularization procedure. The most effective strategy consisted in performing myocardial scintigraphy in the 146 patients with severe TOD and, among the 239 other patients without severe TOD, in those with CAC ≥ 100 AU: this strategy provided 82% sensitivity for SMI diagnosis, and identified all the patients with stenoses.ConclusionThe ESC-EASD guidelines suggesting SMI screening in asymptomatic patients with very high risk assessed by severe TOD or high CAC score appears effective and could identify all the patients with stenoses eligible for revascularization.

The Value of Colon Cancer Screening in Developing Countries

Abstract Objectives: Colorectal cancer is the third most diagnosed cancer worldwide and the second most common cause of cancer death. If diagnosed at an early stage, however, it is one of the most curable malignancies. Patients with biopsy-proven adenocarcinoma of the colon without evidence of distant metastasis, and without contraindications to major surgery, are commonly treated with surgical resection. Methods and results: A 49-year-old male patient without any significant history is admitted at Surgery 5 Service, Cluj-Napoca for abdominal pain, diarrhoea, and important weight loss in the last 7 months. CT showed thickening of the sigmoid colon as well as bladder and small bowel invasion. The final diagnosis was completed by a colonoscopy and biopsy which was of stenotic sigmoid tumour, chemo treated. Unfortunately, the chemotherapy was unsuccessful, as the tumour did not regress. A multidisciplinary team was gathered debating the possibility of pelvic exenteration. As of surgical treatment, the following were performed: Sigmoidectomy with manual colo-rectal T-T anastomosis and central lymphadenectomy, ileal segmental resection with manual T-T anastomosis, resection of 2/3 of bladder, jejunostomy, evacuation of bladder abscess and the introduction of a double J ureteral stent. Consecutive to all procedures, the patient is in good health and can live a normal life. Conclusion: Even though surgery is curative in most cases of colorectal cancer, the survival rate of unoperated colorectal cancer is 0%. Thus, it is of utmost importance to diagnose colorectal cancer as soon as possible. Identification of populations at risk and screening of asymptomatic patients are therefore crucial imperatives.

Link between Two Decades of Oral Contraceptives and Bowel Infarction: A Case Report

Abstract Objectives: Partial or total necrosis of the bowel is a frequent cause of obstruction of the mesenteric artery or vein. Mesenteric infarction is usually the consequence of other associated pathologies of the patient and most often revealed by acute intestinal obstruction. Thus, it is of utmost importance to recognize the risk factors and treat all conditions that might have a link with a hypercoagulability state. Acute mesenteric ischemia is pathology difficult to treat due to the nonspecific symptomatology and late diagnosis consequently. Moreover, the majority the patients have other comorbidities resulting a mortality in over 50% of the cases. Methods and results: Identified risk factors in our patient’s case for the thrombus formations were oral contraceptive medication, hypertension, and obesity. Other secondary causes of Superior Mesenteric Vein (SMV) and Portal Vein (PV) thrombosis were investigated but all tests were negative leading to the incrimination of obesity and chronic use of oral contraceptives for over two decades. Conclusion: Rare, life-threatening complications of associated pathologies such as venous mesenteric thrombosis and bowel obstruction are unanticipated. Thus, it is of utmost importance to diagnose complications and risk factors as soon as possible whose resolutions will make it possible to prolong survival of many patients. Identification of populations at risk and screening of asymptomatic patients are therefore crucial imperatives.

Impacto da COVID-19 sobre a função tireoidiana de crianças e adolescentes: uma revisão integrativa

OBJECTIVE: To evaluate changes in thyroid function associated with COVID-19 in pediatric patients, their etiology, clinical and laboratory profile, as well as evolution. METHODS: A search was carried out in PubMed, Scielo, Lilacs and Google Scholar databases, between january 2020 and july 2022, through the combination of the descriptors: COVID-19, thyroid function, and pediatric population, in accordance with MeSH and DeSC, and in Portuguese, English and Spanish. RESULTS: After applying the inclusion and exclusion criteria, 8 of the 842 articles found were considered eligible for review, totalling a sample of 288 patients, aged 1 month to 18 years, affected by different forms of thyroid function disfunctions related to COVID-19, including subacute thyroiditis, TSH elevation in patients with pediatric multisystem inflammatory syndrome, euthyroid sick syndrome, and autoimmune hyper or hypothyroidism diagnosed after COVID-19 or exacerbated by the infection. The articles suggest that periodic assessment of thyroid function in children and adolescents affected by COVID-19 may allow screening of asymptomatic patients and early elucidate clinical conditions associated to thyroid pathology in the post-SARSCoV-2 infection period. CONCLUSIONS: The analysed articles, despite their small number, are relevant because they describe illustrative cases of thyroid dysfunction related to COVID-19 infection in the pediatric population. This work also points to the need for further studies in children and adolescents to define more precisely the evolution of these thyroid disfunctions, the best way to investigate them, and their most appropriate management, considering that thyroid function is essential for a full pediatric development.

Indications for carotid Doppler ultrasound in asymptomatic patients - are we ordering it correctly?

Carotid arteries are frequently the site of pathologies, the most common being atherosclerosis, which may result in the formation of plaques, causing stenosis. Doppler ultrasound is currently the exam of choice for assessment of the carotid arteries in asymptomatic patients to screen for and diagnose vascular lesions. Current guidelines recommend screening patients who have risk factors for carotid stenosis and who are able and willing to undergo medical treatment and/or carotid intervention. Screening asymptomatic patients in the general adult population who have no significant risk factors is not recommended. To assess whether medical experts rely on the literature to request Doppler ultrasound for screening. A retrospective selection of patients was performed based on requests for carotid ultrasound. The data collected were computed and analyzed using RStudio version 1.3.959. The request was evaluated as appropriate as long as the patients presented at least one risk factor for carotid plaques. Fifty-five out of 152 patients met criteria for carotid screening. The most frequent indication in the study population was vascular check-up. Arterial hypertension was the most prevalent risk factor. Vascular surgery specialists were more likely to order the exam correctly (odds ratio for correct indications: 3.52 [CI 1.14 - 10.87], with p=0.02). The rate of correct Doppler ultrasound requests was 36% (95%CI 29 to 42%). An excess of requests for carotid ultrasound screening was found in this study. Vascular surgeons more often requested the test correctly.

Indicações para ecodoppler de carótidas em pacientes assintomáticos - estamos solicitando corretamente?

Abstract Background Carotid arteries are frequently the site of pathologies, the most common being atherosclerosis, which may result in the formation of plaques, causing stenosis. Doppler ultrasound is currently the exam of choice for assessment of the carotid arteries in asymptomatic patients to screen for and diagnose vascular lesions. Current guidelines recommend screening patients who have risk factors for carotid stenosis and who are able and willing to undergo medical treatment and/or carotid intervention. Screening asymptomatic patients in the general adult population who have no significant risk factors is not recommended. Objectives To assess whether medical experts rely on the literature to request Doppler ultrasound for screening. Methods A retrospective selection of patients was performed based on requests for carotid ultrasound. The data collected were computed and analyzed using RStudio version 1.3.959. Results The request was evaluated as appropriate as long as the patients presented at least one risk factor for carotid plaques. Fifty-five out of 152 patients met criteria for carotid screening. The most frequent indication in the study population was vascular check-up. Arterial hypertension was the most prevalent risk factor. Vascular surgery specialists were more likely to order the exam correctly (odds ratio for correct indications: 3.52 [CI 1.14 - 10.87], with p=0.02). The rate of correct Doppler ultrasound requests was 36% (95%CI 29 to 42%). Conclusions An excess of requests for carotid ultrasound screening was found in this study. Vascular surgeons more often requested the test correctly.

Prospective Evaluation of SARS-CoV-2 Rapid Antigen Test for Screening of Asymptomatic Caregivers.

This study aimed to assess clinical performance of a rapid antigen test (RAT) for screening asymptomatic patients during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) omicron outbreak. RAT with the routine real-time reverse transcription-polymerase chain reaction (rRT-PCR) using the same nasopharyngeal swab in universal transport medium was performed for rapid screening of asymptomatic caregivers of emergent patients from March to April 2022 in a tertiary-care hospital in Korea. Clinical performance of RAT compared to that analyzed by rRT-PCR was evaluated. A total of 900 caregivers were enrolled in this study, of which 14 (1.6%) were RAT-positive and 44 (5.0%) were positive for rRT-PCR. Overall sensitivity and specificity of RAT were 31.8% and 100.0%, respectively. Caution must be taken when using RAT as a screening test for asymptomatic caregivers as this may lead to outbreaks among high-risk patients.

The role of biomarkers to increase the detection of early-onset colorectal cancer

Colorectal cancer is the third most diagnosed cancer worldwide with an estimated 1.93 million cases diagnosed in 2020. Over the past few decades there has been a dramatic rise in the incidence of early onset colorectal cancer, defined as colorectal cancer diagnosed in those aged under 50 years. The largest predictor of survival is early stage at diagnosis, therefore ways to improve prompt diagnosis of early onset colorectal cancer at an early stage is an effective way of managing the impact of this rising disease. Diagnosing colorectal cancer in younger patients has unique challenges with patients falling outside the age of most screening programs and early symptoms of colorectal cancer being common, non-specific and initially intermittent. While colonoscopy remains the gold standard investigation, it is a limited and expensive resource, and current patterns of practice result in large numbers of patients being scoped unnecessarily. The development and use of new and novel non-invasive biomarkers may help (either alone or in combination) identify either symptomatic patients in primary care, or aid with screening asymptomatic patients to focus resources where they are needed most. This review discusses challenges around diagnosing early onset colorectal cancer, with an overview of both current and future methods that might help overcome these challenges. These include increased assessment of familial risk, and the measurement of different biomarkers including faecal haemoglobin, markers of inflammation, gut microbiota, and selected metabolites.