Faecal immunochemical tests for the diagnosis of symptomatic colorectal cancer in primary care: the benefit of more than one sample

Objective: Faecal immunochemical tests (FITs) are used to screen for colorectal cancer (CRC) and as diagnostic aids in symptomatic patients. However, the number of samples per FIT varies. It is unclear if there is any advantage to analyse multiple-sample FITs in symptomatic patients.

Design and setting: This is a post hoc analysis of a retrospective study that included all cases of CRC and adenomas with high-grade dysplasia (HGD) between 2005 and 2009 in the county of Jämtland, Sweden.

Subjects: All patients with CRC and adenomas with HGD that initially presented with symptoms to primary care and delivered FITs.

Main outcome measure: The likelihood of a positive FIT in cases of CRC and adenomas with HGD; when analysing one, two or three samples.

Results: Of 195 patients, 160 delivered three-sample FITs. Using the 139 cases in which at least one sample was positive, the likelihood of detecting a positive sample upon analysis of only one of the three samples was 0.91 (95% CI: 0.85–0.95), indicating that 13 positive cases may have been missed.

Conclusion: Use of a one-sample FIT instead of a three-sample FIT as a diagnostic aid may result in the missing of one tenth of symptomatic CRCs and adenomas with HGD.     

Differences in diagnostic activity in general practice and findings for individuals invited to the danish screening programme for colorectal cancer: a population-based cohort study

Objective: To investigate the diagnostic activity in general practice and the cumulative incidence of colorectal cancer (CRC) in individuals invited to the Danish national screening programme for CRC.

Design: A historical population-based cohort study.

Setting: The Danish CRC screening programme and general practice.

Subjects: The 376,198 individuals invited to the Danish CRC screening programme from 1 March to 31 December 2014.

Main outcome Measures: The diagnostic activity (consultations and haemoglobin measures) in general practice in the year preceding the screening invitation and the cumulated incidence of CRC in the year following the screening invitation.

Results: Screening participants had significantly higher diagnostic activity than non-participants. Individuals with a positive faecal immunochemical test (FIT) had higher diagnostic activity compared to individuals with a negative FIT, and a small increase in the months leading up to the invitation. Individuals with a screen-detected CRC had lower diagnostic activity than individuals with no CRC. In total, 308 (25.3%) of CRCs diagnosed in the invited population were diagnosed outside the screening programme. Non-participants with CRC more often had low socio-economic status, high comorbidity and stage IV CRC than participants with CRC.

Conclusions: There was a tendency that participants and those with a positive FIT had a higher diagnostic activity the year before the screening. This was not seen for those with CRC detected through screening. CRC must still be diagnosed in general practice in the invited population and non-participants are of special interest as they have higher risk of late stage CRC.

• Key Points

• Current awareness:Individuals with colorectal cancer (CRC) in screening may be symptomatic and CRC may still occur outside screening in the invited population.

• Most important points:The majority of individuals with CRC in screening cannot be expected to be diagnosed on symptomatic presentation in general practice

• GPs have to be aware that CRC still occurs outside screening in the invited population

• Non-participants with CRC are often deprived and have late stage CRC

     

Health Care Provider Characteristics Associated With Colorectal Cancer Screening Preferences and Use

ObjectiveTo assess health care provider (HCP) preferences related to colorectal cancer (CRC) screening overall, and by HCP and patient characteristics.Participants and MethodsWe developed a survey based on the Theoretical Domains Framework to assess factors associated with CRC screening preferences in clinical practice. The survey was administered online November 6 through December 6, 2019, to a validated panel of HCPs drawn from US national databases and professional organizations. The final analysis sample included 779 primary care clinicians (PCCs) and 159 gastroenterologists (GIs).ResultsHCPs chose colonoscopy as their preferred screening method for average-risk patients (96.9% (154/159) for GIs, 75.7% (590/779) for PCCs). Among PCCs, 12.2% (95/779) preferred multi-target stool DNA (mt-sDNA), followed by fecal immunochemical test (FIT), (7.3%; 57/779) and guaiac-based fecal occult blood test (gFOBT) (4.8%; 37/779). Preference among PCCs and GIs generally shifted toward noninvasive screening options for patients who were unable to undergo invasive procedures; concerned about taking time from work; unconvinced about need for screening; and refusing other screening recommendations. Among PCCs, preference for mt-sDNA over FIT and gFOBT was less frequent in larger compared with smaller clinical practices. Additionally, preference for mt-sDNA over FIT was more likely among PCCs with more years of clinical experience, higher patient volumes (> 25/day), and practice locations in suburban and rural settings (compared to urban).ConclusionBoth PCCs and GIs preferred colonoscopy for CRC screening of average-risk patients, although PCCs did so less frequently and with approximately a quarter preferring stool-based tests (particularly mt-sDNA). PCCs’ preference varied by provider and patient characteristics. Our findings underscore the importance of informed choice and shared decision-making about CRC screening options.     

Circulating cell-free nucleic acids as biomarkers in colorectal cancer screening and diagnosis - an update

Introduction: Screening methods for one of the most frequently diagnosed malignancy, colorectal cancer (CRC), have limitations. Circulating cell-free nucleic acids (cfNA) hold clinical relevance as screening, prognostic and therapy monitoring markers.

Area covered: In this review, we summarize potential CRC-specific cfNA biomarkers, the recently developed sample preparation techniques, their applications, and pitfalls.

Expert opinion: Automated extraction of cfDNA is highly reproducible, however, cfDNA yield is less compared to manual isolation. Quantitative and highly sensitive detection techniques (e.g. digital PCR, NGS) can be applied to analyze genetic and epigenetic changes. Detection of DNA mutations or methylation in cfDNA and related altered levels of mRNA, miRNA, and lncRNA may improve early cancer recognition, based on specific, CRC-related patterns. Detection of cfDNA mutations (e.g. TP53, KRAS, APC) has limited diagnostic sensitivity (40–60%), however, methylated DNA including SEPT9, SFRP1, SDC2 can be applied with higher sensitivity (up to 90%) for CRC. Circulating miRNAs (e.g. miR-21, miR-92, miR-141) provide comparably high sensitivity for CRC as the circulating tumor cell mRNA markers (e.g. EGFR, CK19, CK20, CEA). Automation of cfNA isolation coupled with quantitative analysis of CRC-related, highly sensitive biomarkers may enhance CRC screening and early detection in the future.     

Review of Chlamydia trachomatis viability methods: assessing the clinical diagnostic impact of NAAT positive results

Introduction: Chlamydia trachomatis (chlamydia) is the most commonly diagnosed bacterial sexually transmitted infection (STI) worldwide. The advancement of molecular techniques has made chlamydia diagnostics infinitely easier. However, molecular techniques lack the information on chlamydia viability. Where in routine diagnostics the detection of chlamydia DNA or RNA might suffice, in other patient scenarios, information on the viability of chlamydia might be essential.

Areas covered: In this review, the authors discuss the specific strengths and limitations of currently available methods to evaluate chlamydia viability: conventional cell culture, messenger RNA (mRNA) detection and viability-PCR (V-PCR).

PubMed and Google Scholar were searched with the following terms: Chlamydia trachomatis, Treatment failure, Anal chlamydia, Microbial viability, Culture, Viability-PCR, Messenger RNA, and Molecular diagnostics

Expert commentary: Several techniques are currently available to determine chlamydia viability and thus the clinical relevance of a positive test result in clinical samples. Depending on the underlying research question, all three discussed techniques have their merits when testing for viability. However, mRNA methods show the most promise in determining the presence of a true infection, in case the chlamydia reticulate body can be specifically detected. Further research is needed to understand how to best apply viability testing in current chlamydia diagnostics.     

Validation of a loop-mediated isothermal amplification assay for rapid diagnosis of pertussis infection in nasopharyngeal samples

Objective: To develop and validate a novel loop-mediated amplification (LAMP) assay for rapid diagnosis (<1 hour) of whooping cough in nasopharyngeal samples versus the gold standard: real-time PCR.

Methods: The study included all nasopharyngeal samples (n = 213) collected from children with clinical suspicion of pertussis admitted to Children’s University Hospital Sant Joan de Déu (Barcelona, Spain) during July–December 2014. Fresh samples were routinely analyzed by real-time PCR and stored for retrospective LAMP analysis, following an easy 30 minute DNA extraction step by Chelex-100.

Results: Performance results of the LAMP assay were: linearity, 10⁵–10¹ CFU/ml; Limit of Detection, 2 CFU/ml; precision (mean CV), 7.38%; diagnostic sensitivity, 96.55%; diagnostic specificity, 99.46%; time to detection, 12–30 minutes.

Conclusion: The new test was shown to be 2.5-fold faster than real-time PCR while maintaining similar levels of analytical and clinical performance. Therefore it could become a useful diagnostic tool for molecular point-of-care testing.     

Genetic and epigenetic markers in colorectal cancer screening: recent advances

Introduction: Colorectal cancer (CRC) is a heterogenous disease which develops from benign intraepithelial lesions known as adenomas to malignant carcinomas. Acquired alterations in Wnt signaling, TGFβ, MAPK pathway genes and clonal propagation of altered cells are responsible for this transformation. Detection of adenomas or early stage cancer in asymptomatic patients and better prognostic and predictive markers is important for improving the clinical management of CRC.

Area covered: In this review, the authors have evaluated the potential of genetic and epigenetic alterations as markers for early detection, prognosis and therapeutic predictive potential in the context of CRC. We have discussed molecular heterogeneity present in CRC and its correlation to prognosis and response to therapy.

Expert commentary: Molecular marker based CRC screening methods still fail to gain trust of clinicians. Invasive screening methods, molecular heterogeneity, chemoresistance and low quality test samples are some key challenges which need to be addressed in the present context. New sequencing technologies and integrated omics data analysis of individual or population cohort results in GWAS. MPE studies following a GWAS could be future line of research to establish accurate correlations between CRC and its risk factors. This strategy would identify most reliable biomarkers for CRC screening and management.     

Multicenter evaluation of the Luminex® ARIES® HSV 1&2 Assay for the detection of herpes simplex virus types 1 and 2 in cutaneous and mucocutaneous lesion specimens

Introduction: The ARIES® HSV 1&2 Assay is a new FDA cleared real-time PCR test for detection and differentiation of HSV-1 and HSV-2 DNA from cutaneous and mucocutaneous lesions. The test is performed on the ARIES® System, an automated sample to answer real-time PCR instrument that provides a closed system and simple workflow for performing molecular testing.

Areas covered: This article reports the clinical performance of the ARIES® HSV 1&2 Assay assessed on 1963 prospectively collected specimens. Assay sensitivities were 91.1–95% (cutaneous) and 97–98.5% (mucocutaneous), and specificities were 88.8–94.2% (cutaneous) and 93.2–95.4% (mucocutaneous), as compared to the ELVIS® HSV test system.

Expert commentary: Detection of HSV DNA by PCR is rapid and more sensitive than traditional culture and immunoassay methods and is being widely adopted in many laboratory settings. Sample to answer molecular platforms like ARIES® will enable routine and non-molecular labs to perform sensitive and rapid molecular testing with ease.     

Impact of treatment modality on clinical outcome in metastatic colorectal cancer patients stratified by metastatic sites

Objectives: To investigate the impact of location of metastases, and therapeutic modality on clinical outcomes in patients with metastatic colorectal cancer (CRC).

Methods: Data for metastatic CRC patients were sourced from the Surveillance, Epidemiology, and End Results (SEER) database (SEER ID: 15309-Nov2017). Patients were classified as follows: Group 1 patients had only liver metastasis; Group 2 patients had liver and lung metastasis; Group 3 patients had more than two metastasis sites. Patients were treated with surgery alone, radiation alone, or surgery plus radiation. The main study outcomes were (1) cancer-specific mortality and (2) survival benefit associated with treatment modality.

Results: A total number of 15,510 patients were included in this study. In Groups 1 and 2, patients treated with surgery plus radiation had a higher cumulative survival compared to other treatment groups (p-value <.001). Group 3 patients showed no significant difference in cumulative survival between the different treatment modalities (p-value = .218). Group 1 patients who received surgery plus radiation had a significantly lower risk of mortality compared to the other treatment groups (p-value <.001), and Group 2 patients who either received radiation treatment alone or surgery plus radiation had a significantly lower risk for mortality than patients who received other treatment modalities (p-value <.001). Multivariate analysis adjusting for known prognostic factors such as tumor sidedness and race did not alter the observed risk conferred by metastasis sites and treatment modalities.

Conclusion: Stratification by metastases sites, and by treatment modality can help multidisciplinary teams to reach a treatment consensus for metastatic CRC.     

Profile of the Roche cobas® EGFR mutation test v2 for non-small cell lung cancer

Introduction: The discovery of driver mutations in non-small cell lung cancer (NSCLC) has led to the development of genome-based personalized medicine. Fifteen to 20% of adenocarcinomas harbor an epidermal growth factor receptor (EGFR) activating mutation associated with responses to EGFR tyrosine kinase inhibitors (TKIs). Individual laboratories’ expertise and the availability of appropriate equipment are valuable assets in predictive molecular pathology, although the choice of methods should be determined by the nature of the samples to be tested and whether the detection of only well-characterized EGFR mutations or rather, of all detectable mutations, is required.

Areas covered: The EGFR mutation testing landscape is manifold and includes both screening and targeted methods, each with their own pros and cons. Here we review one of these companion tests, the Roche cobas® EGFR mutation test v2, from a methodological point of view, also exploring its liquid-biopsy applications.

Expert commentary: The Roche cobas® EGFR mutation test v2, based on real time RT-PCR, is a reliable option for testing EGFR mutations in clinical practice, either using tissue-derived DNA or plasma-derived cfDNA. This application will be valuable for laboratories with whose purpose is purely diagnostic and lacking high-throughput technologies.     

Baseline breath alcohol concentration in Nigerian commercial drivers and motorcyclists

Objective: We sought to determine breath alcohol concentration (BrAC) in a sample of consenting Nigerian commercial drivers and motorcyclists and relate values obtained to some social parameters and practices.

Method: A cross-sectional study of randomly selected, consenting commercial drivers, and motorcyclists in two Nigerian cities was undertaken. We obtained data on subjects’ sociodemographics, driving/riding related experiences and practices with the aid of a pretested structured questionnaire. We determined their BrAC and analyzed data using SPSS version 17.0. Statistical significance was inferred at p ≤ 0.05.

Result: One hundred ninety respondents aged 20–65 years mean (SD) 40 (11.28) were studied. They were 112 (58.9%) drivers, 78 (41.1%) motorcyclists, and predominantly males (98.9%). A significant proportion of motorcyclists were aged <40 years and most drivers >40 years (p < 0.001). Respondents’ educational attainment did not differ significantly with age groups and status; however, 6.8% had no formal education.

Alcohol use decreased significantly with increasing years of experience (p < 0.001). Note that 68.9% of respondents tested positive with the breathalyzer with blood alcohol concentration (BAC) levels 0.01–1.8 mg/ml with mean (SD) at 0.16 (0.32) mg/ml. In total, 51.1% of respondents had BAC values ≥0.1% while 7.9% had BAC ≥0.5 mg/ml. A total of 92.6% admitted use of various measures to enhance their performances and overcome fatigue.

Conclusion: The drink driving/riding law in Nigeria needs to be revised to suit prevailing circumstance and enforced.     

Shoulder muscle activity during the modified dynamic relocation test and side-lying shoulder external rotation: a cross-sectional study on asymptomatic individuals

Objectives: (1) to compare activity levels between monitored muscles during the dynamic relocation test (DRT); (2) to assess changes in muscle activation variability over 10 trials; (3) to assess within-muscle difference activity levels between the DRT and the unloaded side-lying shoulder external rotation exercise.

Methods: This is a cross-sectional, laboratory-based, repeated measures study. Thirty asymptomatic individuals performed the DRT and unloaded side-lying external rotation. The order of exercises was randomized. Superficial electromyography was used for recording the supraspinatus, infraspinatus, middle deltoid, posterior deltoid, pectoralis major, and latissimus dorsi muscles. The main outcome measures were mean muscle activity, expressed as % of maximal isometric voluntary contraction.

Results: We found significant between-muscles differences in activity (F_t = 14.11, p < 0.001) during the DRT. Post hoc analysis suggested between-trial variability did not change over the 10 trials, (F = 18.2, p < 0.001). Within-muscle comparisons between the DRT and side-lying shoulder external rotation suggested significant differences between these exercises (F = 32.37, p < 0.001).

Conclusions: considering the monitored muscles, supraspinatus, infraspinatus, pectoralis major, and latissimus dorsi are the main muscles contracting during the DRT. Of all monitored muscles, supraspinatus muscle was the only one presenting higher activity levels during the DRT when compared to the unloaded side-lying shoulder external rotation.     

Secukinumab in moderate-to-severe plaque psoriasis: a multi-center,retrospective, real-life study up to 52 weeks observation

Objectives: To evaluate efficacy and safety of the anti-IL-17 drug secukinumab in a real-life large cohort of patients with moderate-to-severe plaque psoriasis in Central Italy.

Methods: Multicenter, retrospective study with an observation period of up to 52 weeks. Efficacy was assessed by Psoriasis Area and Severity Index (PASI) score; clinical and laboratory examinations were performed at baseline and at weeks 4, 12, 24, 36, and 52.

Results: A 90% and a 100% PASI score reduction (PASI90 and PASI100) were reported in 67.5% and 55% of patients at week 12, respectively. A rapid improvement of skin lesions was observed particularly in young patients and in patients naïve to biologics: at week 4, the achievement of PASI90 and PASI100 was higher in younger patients (odds ratio [OR] 0.95, and 0.95; p = 0.003, and 0.005, respectively); PASI90 was achieved by 42.0% of patients naïve to biologics and by 17.0% of patients with prior exposure to biologics (PBT) (OR 0.24; p = 0.001); and PASI100 was reached by 25.5% of naïve patients and 9.8% of PBT (OR 0.28; p = 0.015).The drug was well tolerated.

Conclusion: Secukinumab was effective in this real-life analysis, with rapid clinical improvement and long-term maintenance of results.     

Lessons learned from the implementation of non-invasive fetal RHD screening

Introduction: In the fight against hemolytic disease of the fetus and newborn, pregnant RhD negative women are offered antenatal and postnatal anti-D immunoglobulin prophylaxis to prevent the development of antibodies against the fetal D antigen. Antenatal prophylaxis has traditionally been provided to all D negative pregnant women, as the fetal RhD type remains unknown until birth. With noninvasive prenatal testing of cell-free DNA, predicting the fetal RhD type has become highly feasible based on analysis of the fetal RHD gene. Fetal RHD screening can guide targeted antenatal prophylaxis, treating only women who carry an RhD positive fetus, thereby avoiding the unnecessary treatment of approximately 40% of the RhD negative women.

Areas covered: Areas covered are the current clinical practice, performance, and challenges of fetal RHD screening, and relevant issues for its implementation.

Expert commentary: Fetal RHD screening is highly accurate, with sensitivities of 99.9%, as reported from clinical programs. From gestational week 10, sensitivities are approximately 99%. Despite challenges in assay design, low levels of cell-free fetal DNA in the maternal plasma, and concerns regarding implementation and medical necessity, the clinical experience with fetal RHD screening and targeted prophylaxis has generated encouraging results, and its future widespread use is expected.     

The importance of pre- and post-test counseling for prenatal cell-free DNA screening for common fetal aneuploidies

Introduction: Prenatal cell-free DNA screening for common fetal aneuploidies has rapidly changed the paradigm of prenatal care. Despite its advantages compared to conventional screening methods, its unexpectedly rapid implementation in clinical practice has generated several ethical and medical issues and misconceptions. Aggressive commercial marketing of cell-free DNA screening and media dissemination of misleading information have added confusion.

Areas covered: This review provides an extensive update and will focus on the importance of pre-and post-test counseling for prenatal cell-free DNA screening not previously discussed extensively in the available literature. Additionally, we report cell-free DNA screening implementation in the largest obstetrical tertiary unit in Finland which is one of few countries that provides all prenatal screening methods free of charge for all women and has a very high uptake of first-trimester screening. This is not a systematical review, but rather a narrative overview which includes the most relevant and recent original publications and reviews covering this issue.

Expert opinion: Despite being the most accurate method for screening of common fetal aneuploidies, the knowledge and counseling should be substantially improved. Cell-free DNA screening is not a replacement for diagnostic testing and its use in prenatal testing is complex and limited.     

Proactive penicillin allergy testing in primary care patients labeled as allergic: outcomes and barriers

Objectives: To promote penicillin allergy testing in an outpatient setting in patients labeled as penicillin allergic, to determine the number of those who are truly allergic, evaluate patient satisfaction with the testing, and educate both patients and clinicians about testing.

Methods: Patients with a history of penicillin allergy listed in their EHR were screened and recruited by their primary care office and referred for penicillin allergy testing. The results of allergy testing and patient satisfaction after testing were the main outcomes. We also surveyed the primary care physicians about perceived barriers to recruitment.

Results: A total of 82 patients were recruited, although only 37 actually underwent testing. None of these 37 had a positive skin test, and none of 36 had a positive oral challenge (1 refused it). Following testing, 2 patients (5%) had subjective reactions within 24 h. Thirty-one patients (84%) responded to a post-testing follow-up questionnaire; 3 (10%) were subsequently treated with a beta-lactam, and all reported that testing provided important information to their medical history. Providers identified time constraints, either their or their patients lack of time, as the major barrier to recruitment.

Conclusions: Penicillin allergy testing safely evaluates patients labeled as penicillin allergic. It is well tolerated, and embraced by the patients who undergo testing. In our study, none of the patients tested had an allergic reaction, but we identified multiple barriers to developing a protocol for testing patients from the primary care setting.     

Impact of shoulder internal rotation on normal sensory response during ulnar nerve-biased neurodynamic testing of asymptomatic individuals

Objective: To determine if substitution of shoulder internal rotation for external rotation during the upper limb neurodynamic test (ULNT₃) evokes comparable ulnar nerve sensory responses in asymptomatic individuals.

Methods: Range of motion, quality, quantity, and distribution of sensory responses in 50 asymptomatic individuals during the traditional ULNT₃ were compared to identical measures during an experimental maneuver using shoulder internal rotation. Quality and quantity of sensory responses were recorded using a 10-cm visual analog scale.

Results: Means of sensory responses for traditional and experimental maneuvers, respectively, were as follows: stretching, 3.84 ± 8.85 and 5.38 ± 2.85 cm; burning, 1.82 ± 2.82 and 2.50 ± 3.10 cm; tingling, 2.13 ± 3.12 and 2.18 ± 2.97 cm; and numbness, 1.04 ± 2.17 and 1.01 ± 2.03 cm. A moderate to strong correlation (ICC = 0.51–0.86) was shown to exist between maneuvers; this relationship was significant (p = .001).

Discussion: Results of this study provide evidence that there was no appreciable difference in sensory responses with regard to burning and tingling when substituting shoulder internal rotation for external rotation during the ULNT₃. The results also suggest that there were only marginal differences in the sensory responses of stretching and numbness during the same substitution.

Conclusion: Patients who have limited glenohumeral external rotation due to pain, instability, and/or articular limitation may benefit from this substitution when presenting with signs of ulnar nerve pathodynamics. Further research will be needed to validate this maneuver in a symptomatic population.

Level of Evidence: Level 2b.     

Clinical performance of the Solana® Point-of-Care Trichomonas Assay from clinician-collected vaginal swabs and urine specimens from symptomatic and asymptomatic women

Background: Solana® (Quidel) is a new rapid (<40 min.) point-of-care (POC) test for qualitative detection of Trichomonas vaginalis (TV) DNA. The assay has two steps: 1) specimen preparation, and 2) amplification and detection using isothermal Helicase-Dependent Amplification (HDA). The objective was to demonstrate the performance of Solana for vaginal swabs and female urines based on comparison to wet mount and TV culture. Performance was also compared to the Aptima-TV assay.

Methods: Urine and four clinician-collected vaginal swabs were collected. The first two were used for FDA composite reference (wet mount; InPouch TV Culture). The third swab was used for Solana. Sensitivity/specificity were based on the reference method. A specimen was considered positive if either test was positive. The fourth swab was for Aptima-TV.

Results: Vaginal swabs and urines were obtained from 501 asymptomatic and 543 symptomatic women. Prevalence of TV by was 11.5%. For swabs, Solana® demonstrated high sensitivity and specificity from asymptomatic (100%/98.9%) and symptomatic (98.6%/98.5%) women, as well as for urines from asymptomatic (98.0%/98.4%) and symptomatic (92.9%/97.9%) women, compared to the reference method. Compared to Aptima-TV, the sensitivity/specificity was 89.7%/99.0% for swabs and 100%/98.9% for urines.

Conclusion: The Solana® assay performed well compared to the reference assays.