Monitoring Treatment Effects Research Articles

Advancing canine mammary tumor diagnostics: Unraveling the diagnostic potential of Cytokeratin 19 through droplet digital PCR analysis

Cytokeratin 19 (CK19) is a complex intracytoplasmic cytoskeletal protein primarily localized in the ducts of the mammary gland and skin epithelial cells. In humans, the expression of CK19 gene within circulating tumor cells (CTCs) extracted from blood samples of breast cancer patients reflects tumor cell activity, offering valuable insights for predicting early metastatic relapse or monitoring treatment effectiveness. However, knowledge of serum tumor markers is limited in veterinary oncology. Recently, droplet digital PCR (ddPCR), has been employed to explore rare target genes due to its heightened sensitivity and accuracy as a novel molecular diagnostic tool. The objectives of this study were to investigate the expression of the CK19 mRNA in CTCs, non-neoplastic mammary tissues, and both benign and malignant canine mammary tumors (CMTs) through ddPCR analysis. In Study I, we optimized the discard volume for blood samples to reduce CK19 contamination from skin epithelial cells post-venipuncture. The results revealed that discarding the initial 3 mL of blood was adequate and effective in eliminating CK19 mRNA contamination. In Study II, after the removal of the initial 3 mL of blood, we investigated CK19 mRNA-positive CTCs in the peripheral blood of normal healthy dogs, including those with benign and malignant CMTs. Intriguingly, CK19 mRNA was undetectable in all blood samples. The expression of CK19 mRNA in mammary tissues was investigated in Study III. The copy number (CN) ratios of the CK19 gene in non-neoplastic mammary tissues (14.77 ± 14.65) were significantly higher (P < 0.05) than those in benign (4.23 ± 3.35) and malignant groups (6.56 ± 5.64). Notably, no difference was observed between the benign and malignant groups. In conclusion, CK19 mRNA appeared unlikely to be a suitable candidate as a biomarker in the peripheral blood of CMTs, while the CN ratio in mammary tissues could serve as a potential discriminator between non-neoplastic and CMT groups, complementing the gold standard of histopathological examination.

Laboratory Tools to Predict CFTR Modulator Therapy Effectiveness and to Monitor Disease Severity in Cystic Fibrosis.

The implementation of cystic fibrosis (CF) transmembrane conductance regulator (CFTR) modulator drugs into clinical practice has been attaining remarkable therapeutic outcomes for CF, a life-threatening autosomal recessive genetic disease. However, there is elevated CFTR allelic heterogeneity, and various individuals carrying (ultra)rare CF genotypes remain without any approved modulator therapy. Novel translational model systems based on individuals' own cells/tissue are now available and can be used to interrogate in vitro CFTR modulator responses and establish correlations of these assessments with clinical features, aiming to provide prediction of therapeutic effectiveness. Furthermore, because CF is a progressive disease, assessment of biomarkers in routine care is fundamental in monitoring treatment effectiveness and disease severity. In the first part of this review, we aimed to focus on the utility of individual-derived in vitro models (such as bronchial/nasal epithelial cells and airway/intestinal organoids) to identify potential responders and expand personalized CF care. Thereafter, we discussed the usage of CF inflammatory biomarkers derived from blood, bronchoalveolar lavage fluid, and sputum to routinely monitor treatment effectiveness and disease progression. Finally, we summarized the progress in investigating extracellular vesicles as a robust and reliable source of biomarkers and the identification of microRNAs related to CFTR regulation and CF inflammation as novel biomarkers, which may provide valuable information for disease prognosis.

Новые подходы к оценке активности и тяжести системной красной волчанки, их применимость в условиях первичной медико-социальной сети

The relevance of systemic lupus erythematosus (SLE) is due to its chronic nature, variety of clinical manifestations and potential severity of organ damage. Epidemiological data indicate an increase in incidence, highlighting the need for accurate diagnosis and effective monitoring of patient conditions. The aim of this review article is to provide an idea of the assessment indices and their place in assessing the severity of SLE. Indices assessing the severity and activity of SLE, such as SLEDAI (Systemic Lupus Erythematosus Disease Activity Index) and SLICC/ACR Damage Index, BILAG (British Isles Lupus Assessment Group), SLAM (Systemic Lupus Activity Measure) and others, play a key role in assessing the condition of patients. They take into account various aspects of the disease, including inflammation, organ damage and overall disease activity. These tools allow standardization of patient assessment and monitoring of treatment effectiveness. For primary care physicians, scoring indices are a valuable tool for screening, diagnosing, and monitoring patients with suspected SLE. They help establish a diagnosis, assess the degree of disease activity and make a decision about referral to a rheumatologist. Thus, the use of indices significantly improves the management of patients with SLE, improving the quality of care and reducing the risk of complications. This article provides an overview of the main assessment tools, taking into account their applicability in the primary health care setting.

The role of bone turnover markers in diagnosis, monitoring, and pathological fractures of osteoporosis.

We investigated the utility of specific biomarkers-namely, c-terminal telopeptide (CTX), n-telopeptide (NTX), deoxypyridinoline (DPD), and tartrate-resistant acid phosphatase (TRAP)-compared to conventional diagnostic methods. We hy-pothesized that these novel biomarkers could hold substantial value in the diagnosis, treatment, and monitoring of osteoporosis. The study was conducted over a three-year period, from January 1, 2020, to January 1, 2023. We enrolled a total of 520 patients aged 50 years or older who had been diagnosed with osteoporosis. Patients undergoing steroid treatments, which are known to contribute to osteoporosis, were excluded from the study. Additionally, we carefully selected and matched a control group consisting of 500 patients based on demographic characteristics relevant to the diagnosis of osteoporosis. This meticulous selection process resulted in a comprehensive cohort comprising 1,020 patients. Throughout the study, patients were closely monitored for a duration of one year to track the occurrence of pathological fractures and assess their overall prognosis. As a result of our rigorous investigation, we identified CTX, NTX, DPD, and TRAP as pivotal biomarkers that play a crucial role in evaluating bone health, monitoring treatment effectiveness, and detecting pathological fractures in the context of osteoporosis. Our study underscores the significance of these biomarkers in advancing the diagnosis and management of osteo-porosis, offering valuable insights into the disease's progression and treatment outcomes.

Reliability and validity of the Turkish version of the New Cleveland Clinic Colorectal Cancer Quality of Life Questionnaire.

This study aims to adapt and validate the Cleveland Clinic Colorectal Cancer Quality of Life Questionnaire (CCF-CaQL) in Turkish, addressing the significant need for reliable, language-specific QoL measures for colorectal cancer (CRC) in Turkiye. This effort fills a critical gap in CRC patient care, enhancing both patient-provider communication and disease-specific QoL assessment. The CCF-CaQL was translated into Turkish, verified for accuracy, and reviewed for clarity and relevance. Eligible patients who underwent colorectal surgery for cancer between July 2021 and July 2022 from six hospitals completed the CCF-CaQL and SF-36 questionnaires. For analysis, confirmatory factor analysis using Smart PLS 4 and descriptive statistics were employed. The questionnaire's reliability and validity were assessed using Cronbach alpha, composite reliability, and the heterotrait-monotrait (HTMT) ratio, along with multicollinearity checks and factor loadings. Nonparametric resampling was used for precise error and confidence interval calculations, and the Spearman coefficient and split-half method were applied for reliability testing. In the study involving 244 colorectal cancer patients, confirmatory factor analysis of the CCF-CaQL indicated effective item performance, with one item removed due to lower factor loading. The questionnaire exhibited high internal consistency, evidenced by a Cronbach alpha value of 0.909. Convergent validity was strong, with all average variance extracted (AVE) values exceeding 0.4. Discriminant validity was confirmed with HTMT coefficients below 0.9, and no significant multicollinearity issues were observed (VIF values < 10). Parallel testing with the SF-36 scale demonstrated moderate to very strong correlations, affirming the CCF-CaQL's comparability in measuring quality of life. The Turkish version of the CCF-CaQL was validated for assessing quality of life in colorectal cancer patients. This validation confirms its reliability and cultural appropriateness for use in Turkiye. The disease-specific nature of the CCF-CaQL makes it a useful tool in clinical and research settings, enhancing patient care by accurately monitoring treatment effects and interventions in the Turkish colorectal cancer patient population.

Mini-review: Biological Movements as Objects of Natural Science

BACKGROUND: Two approaches to biological movement have dominated the field, the computational approach (internal models) and the approach based on laws of nature pioneered by several researchers including Michael Turvey. AIM AND METHOD: We review a body of literature exploring and expanding the approach based on laws of nature. We show, in particular, how this approach fits the philosophical traditions of Merleau-Ponty, the theory of control with spatial referent coordinates, the principle of abundance, and the concept of performance-stabilizing synergies using the uncontrolled manifold hypothesis. RESULTS: Currently, this scheme of motor control has been applied successfully in studies of a variety of effectors, from single motor units to the whole body, a variety of tasks, and various populations. It led to the discovery of new phenomena and new interpretations of known phenomena. It has been productive in studies of neurological patients offering new understanding of some of the common pathologies (e.g., spasticity) and new tools for early diagnosis of various subcortical disorders and monitoring treatment effects. CONCLUSION: Currently, this field faces a number of challenges including the following: Mapping steps in the hierarchical control scheme on neurophysiological structures and circuits, understanding the relative role of intra-muscle (spinal) and multi-effector (supraspinal) synergies, expanding studies of movements in intact animals and animal preparation, and moving beyond the current scheme to fields traditionally associated with psychology. Just like the current scheme represents moving “outside the box” of classical mechanics, a step outside the current thinking is needed.

The role of the albumin-to-creatinine ratio in the diagnosis of diabetic kidney disease (literature review and own findings)

Based on our own practical experience and data from scientific literature, we can assert that measuring the ratio of albumin to creatinine and calculating the glomerular filtration rate are important tools for the timely diagnosis of chronic kidney disease (CKD), monitoring treatment effectiveness, and determining the dynamics of a patient’s renal condition. Early diagnosis of CKD allows us to take necessary measures to slow down or even halt the progression of the disease. By timely administering nephroprotective drugs, such as SGLT-2 inhibitors, we can improve the prognosis and quality of life for patients, which holds medical, social, and economic significance.

Genetic variants underlying the neuro‐anatomical signatures of hypertension measured on structural MRI

AbstractBackgroundHypertension (HTN) is associated with gray matter (GM) atrophy and increased white matter hyperintensity (WMH) burden, increasing their susceptibility to Alzheimer’s disease and related dementias. We developed a machine learning based model to quantify spatial patterns of abnormality recognizing HTN‐related brain changes (SPARE‐HTN) from structural magnetic resonance images (sMRI). We performed a genome wide association study (GWAS) to identify the genetic variants and associated biological traits that underlie the “expression” of HTN‐related brain changes, i.e., the individualized SPARE‐HTN index.MethodSPARE‐HTN model was trained on the large multi‐study iSTAGING dataset, with regional GM volumes from T1‐weighted images and lobar WMH volumes from T2‐weighted FLAIR images used as imaging features. GWAS was carried out in a subset of N = 7490 (46% Female, Age = 65.5±7 years) hypertensive participants from UK‐Biobank. A GWAS of SPARE‐HTN scores was run using linear regression with Plink, correcting for the top 40 genetic principal components, age, sex, and intracranial volume. Significant SNPs were identified and mapped to functional genes using the Functional Mapping and Annotation (FUMA) platform; and candidate SNPs were mapped to the GWAS catalog.ResultSPARE‐HTN was associated with regional atrophy most prominent in perisylvian and temporal cortex and increased WMH volumes, particularly in frontal white matter. SPARE‐HTN scores showed better discriminative power between normal and stage 1 participants (Cohen’s‐d effect size, d = 0.2) and stage 2 (d = 0.71) hypertensive participants when compared to total WMH volume (d = 0.04 and 0.38, respectively). GWAS identified N = 321 independently significant SNPs, of which a subset N = 46 candidate SNPs were mapped to 6 genes (ICA1L, CARF, WDR12, NBEAL1, KRT8P15, CYP20A1) in Chromosome 2 (Figure 2). These genes were previously reported to be associated with several cardiovascular conditions including coronary artery disease and stroke, and with increased WM damage on sMRI and diffusion MRI (Figure 3).ConclusionThe individualized imaging marker, SPARE‐HTN, was associated with genes relevant to HTN with traits including cardiovascular conditions and higher prevalence of WMH, and was more sensitive to HTN than total WMH volume. SPARE‐HTN is a useful tool to characterize HTN‐related brain changes and monitor treatment effects at an individual level.

Genetic variants underlying the neuro‐anatomical signatures of hypertension measured on structural MRI

AbstractBackgroundHypertension (HTN) is associated with gray matter (GM) atrophy and increased white matter hyperintensity (WMH) burden, increasing their susceptibility to Alzheimer’s disease and related dementias. We developed a machine learning based model to quantify spatial patterns of abnormality recognizing HTN‐related brain changes (SPARE‐HTN) from structural magnetic resonance images (sMRI). We performed a genome wide association study (GWAS) to identify the genetic variants and associated biological traits that underlie the “expression” of HTN‐related brain changes, i.e., the individualized SPARE‐HTN index.MethodSPARE‐HTN model was trained on the large multi‐study iSTAGING dataset, with regional GM volumes from T1‐weighted images and lobar WMH volumes from T2‐weighted FLAIR images used as imaging features. GWAS was carried out in a subset of N = 7490 (46% Female, Age = 65.5±7 years) hypertensive participants from UK‐Biobank. A GWAS of SPARE‐HTN scores was run using linear regression with Plink, correcting for the top 40 genetic principal components, age, sex, and intracranial volume. Significant SNPs were identified and mapped to functional genes using the Functional Mapping and Annotation (FUMA) platform; and candidate SNPs were mapped to the GWAS catalog.ResultSPARE‐HTN was associated with regional atrophy most prominent in perisylvian and temporal cortex and increased WMH volumes, particularly in frontal white matter. SPARE‐HTN scores showed better discriminative power between normal and stage 1 participants (Cohen’s‐d effect size, d = 0.2) and stage 2 (d = 0.71) hypertensive participants when compared to total WMH volume (d = 0.04 and 0.38, respectively). GWAS identified N = 321 independently significant SNPs, of which a subset N = 46 candidate SNPs were mapped to 6 genes (ICA1L, CARF, WDR12, NBEAL1, KRT8P15, CYP20A1) in Chromosome 2 (Figure 2). These genes were previously reported to be associated with several cardiovascular conditions including coronary artery disease and stroke, and with increased WM damage on sMRI and diffusion MRI (Figure 3).ConclusionThe individualized imaging marker, SPARE‐HTN, was associated with genes relevant to HTN with traits including cardiovascular conditions and higher prevalence of WMH, and was more sensitive to HTN than total WMH volume. SPARE‐HTN is a useful tool to characterize HTN‐related brain changes and monitor treatment effects at an individual level.

Routes to standardisation for tau protein measurement in CSF

AbstractBackgroundCSF biomarkers are the target of several commercially available in vitro diagnostic (IVD) kits allowing an early diagnosis of Alzheimer’s disease (AD) and eventually the monitoring of treatment effects in clinical trials. Tau hyper‐phosphorylation is one of the main hallmarks of AD and its measurement provides higher accuracy to stratify patients at an early‐stage.Due to the rapid advancements in proteomics, standardisation of measurements can be achieved through the development of reference measurement procedures (RMPs) and certified reference materials (CRMs).MethodSI‐traceable protein and peptide primary calibrators were developed for t‐tau and p‐tau: mass fraction was determined by amino acid analysis and purity was assessed by LC‐MS at high resolution. CSF pools at different tau concentration were used for the development and validation of LC‐IDMS candidate RMP and their commutability was assessed.ResultAn LC‐IDMS candidate reference method was develop and validated in CSF for t‐tau using a SI‐traceable candidate protein primary calibrator. Three different CSF pools (low, medium, high) were successfully quantified with a relative expanded uncertainty below 10%. The commutability of 13 matrix‐based CRMs was assessed involving 8 immunoassays from 5 IVD providers by measuring 40 single CSF donations.According to the AT(N) classification, high levels of p‐tau(181) are highly correlated to tau pathology and commercially available immunoassays are able to target this specific epitope. We conducted a feasibility study on the development of a candidate reference method for p‐tau(181) in CSF relying on a SI‐traceable peptide primary calibrator and an antibody‐free sample preparation workflow.New assays targeting p‐tau(217) in CSF and plasma were also developed, making it necessary the organisation of standardisation initiatives. We sourced and characterised multiple phosphopeptide primary calibrators as well as a GSK3beta‐phosphorylated protein primary calibrator for the development of an LC‐MS RMP including an immunoprecipitation step in the sample preparation workflow.Conclusiontau is considered as a priority for the IFCC WG on NDD and the development of SI traceable RMPs and CRMs is essential to underpin a worldwide standardisation of results. This will help IVD providers to address the traceability requirements of the IVDR thus facilitating regulatory approvals of the kits.

Type of anesthesia for cancer resection surgery: No differential impact on cancer recurrence in mouse models of breast cancer.

Surgery is essential for curative treatment of solid tumors. Evidence from recent retrospective clinical analyses suggests that use of propofol-based total intravenous anesthesia during cancer resection surgery is associated with improved overall survival compared to inhaled volatile anesthesia. Evaluating these findings in prospective clinical studies is required to inform definitive clinical guidelines but will take many years and requires biomarkers to monitor treatment effect. Therefore, we examined the effect of different anesthetic agents on cancer recurrence in mouse models of breast cancer with the overarching goal of evaluating plausible mechanisms that could be used as biomarkers of treatment response. To test the hypothesis that volatile anesthesia accelerates breast cancer recurrence after surgical resection of the primary tumor, we used three mouse models of breast cancer. We compared volatile sevoflurane anesthesia with intravenous propofol anesthesia and used serial non-invasive bioluminescent imaging to track primary tumor recurrence and metastatic recurrence. To determine short-term perioperative effects, we evaluated the effect of anesthesia on vascular integrity and immune cell changes after surgery in animal models. Survival analyses found that the kinetics of cancer recurrence and impact on survival were similar regardless of the anesthetic agent used during cancer surgery. Vascular permeability, immune cell infiltration and cytokine profiles showed no statistical difference after resection with inhaled sevoflurane or intravenous propofol anesthesia. These preclinical studies found no evidence that choice of anesthetic agent used during cancer resection surgery affected either short-term perioperative events or long-term cancer outcomes in mouse models of breast cancer. These findings raise the possibility that mouse models do not recapitulate perioperative events in cancer patients. Nonetheless, the findings suggest that future evaluation of effects of anesthesia on cancer outcomes should focus on cancer types other than breast cancer.

Real-time PCR for diagnosing and monitoring treatment effect of Strongyloides stercoralis infection in a non-endemic setting

Real-time PCR for diagnosing and monitoring treatment effect of Strongyloides stercoralis infection in a non-endemic setting

Interpreting growth hormone and IGF-I results using modern assays and reference ranges for the monitoring of treatment effectiveness in acromegaly.

Standard treatment for acromegaly focuses on the achievement of target absolute levels of growth hormone (GH) and insulin-like growth factor (IGF-I). The appropriateness of these targets when measured using modern assay methods is not well defined. This paper reviews biochemical status assessed using methods available at the time and associated clinical outcomes. GH measurements were shown to provide an indication of changes in tumor size, and failure of GH suppression after glucose stimulation is associated with tumor recurrence. IGF-I levels were more closely associated with changes in symptoms and signs. Reduced GH and IGF-I concentrations were shown to be associated with increased longevity, although the degree of increase has only been analyzed for GH. Lowering of GH and IGF-I has consistently been associated with improved outcomes; however, absolute levels reported in previous studies were based on results from methods and reference ranges that are now obsolete. Applying previously described absolute thresholds as targets (e.g. "normal" IGF-I level) when using current methods is best applied to those with active acromegaly symptoms who could benefit from further lowering of biochemical markers. In asymptomatic individuals with mild IGF-I or GH elevations, targeting biochemical "normalization" would result in the need for combination pharmacotherapy in many patients without proven benefit. Measurement of both GH and IGF-I remains an essential component of diagnosis and monitoring the effectiveness of treatment in acromegaly; however, treatment goals based only on previously identified absolute thresholds are not appropriate without taking into account the assay and reference ranges being employed. Treatment goals should be individualized considering biochemical improvement from an untreated baseline, symptoms of disease, risks, burdens and costs of complex treatment regimens, comorbidities, and quality of life.

First-Year Experience of Managing Urology Patients With Home Uroflowmetry: Descriptive Retrospective Analysis.

Lower urinary tract symptoms affect a large number of people of all ages and sexes. The clinical assessment typically involves a bladder diary and uroflowmetry test. Conventional paper-based diaries are affected by low patient compliance, whereas in-clinic uroflowmetry measurement face challenges such as patient stress and inconvenience factors. Home uroflowmetry and automated bladder diaries are believed to overcome these limitations. In this study, we present our first-year experience of managing urological patients using Minze homeflow, which combines home uroflowmetry and automated bladder diaries. Our objective was 2-fold: first, to provide a description of the reasons for using homeflow and second, to compare the data obtained from homeflow with the data obtained from in-clinic uroflowmetry (hospiflow). A descriptive retrospective analysis was conducted using Minze homeflow between July 2019 and July 2020 at a tertiary university hospital. The device comprises a Bluetooth-connected gravimetric uroflowmeter, a patient smartphone app, and a cloud-based clinician portal. Descriptive statistics, Bland-Altman plots, the McNemar test, and the Wilcoxon signed rank test were used for data analysis. The device was offered to 166 patients, including 91 pediatric and 75 adult patients. In total, 3214 homeflows and 129 hospiflows were recorded. Homeflow proved valuable for diagnosis, particularly in cases where hospiflow was unreliable or unsuccessful, especially in young children. It confirmed or excluded abnormal hospiflow results and provided comprehensive data with multiple measurements taken at various bladder volumes, urge levels, and times of the day. As a result, we found that approximately one-fourth of the patients with abnormal flow curves in the clinic had normal bell-shaped flow curves at home. Furthermore, homeflow offers the advantage of providing an individual's plot of maximum flow rate (Q-max) versus voided volume as well as an average or median result. Our findings revealed that a considerable percentage of patients (22/76, 29% for pediatric patients and 24/50, 48% for adult patients) had a Q-max measurement from hospiflow falling outside the range of homeflow measurements. This discrepancy may be attributed to the unnatural nature of the hospiflow test, resulting in nonrepresentative uroflow curves and an underestimation of Q-max, as confirmed by the Bland-Altman plot analysis. The mean difference for Q-max was -3.1 mL/s (with an upper limit of agreement of 13 mL/s and a lower limit of agreement of -19.2 mL/s), which was statistically significant (Wilcoxon signed rank test: V=2019.5; P<.001). Given its enhanced reliability, homeflow serves as a valuable tool not only for diagnosis but also for follow-up, allowing for the evaluation of treatment effectiveness and home monitoring of postoperative and recurrent interventions. Our first-year experience with Minze homeflow demonstrated its feasibility and usefulness in the diagnosis and follow-up of various patient categories. Homeflow provided more reliable and comprehensive voiding data compared with hospiflow.

Circulating tumor DNA-based copy-number profiles enable monitoring treatment effects during therapy in high-grade serous carcinoma

Circulating tumor DNA (ctDNA) analysis has emerged as a promising tool for detecting and profiling longitudinal genomics changes in cancer. While copy-number alterations (CNAs) play a major role in cancers, treatment effect monitoring using copy-number profiles has received limited attention as compared to mutations. A major reason for this is the insensitivity of CNA analysis for the real-life tumor-fraction ctDNA samples. We performed copy-number analysis on 152 plasma samples obtained from 29 patients with high-grade serous ovarian cancer (HGSC) using a sequencing panel targeting over 500 genes. Twenty-one patients had temporally matched tissue and plasma sample pairs, which enabled assessing concordance with tissues sequenced with the same panel or whole-genome sequencing and to evaluate sensitivity. Our approach could detect concordant CNA profiles in most plasma samples with as low as 5% tumor content and highly amplified regions in samples with ∼1% of tumor content. Longitudinal profiles showed changes in the CNA profiles in seven out of 11 patients with high tumor-content plasma samples at relapse. These changes included focal acquired or lost copy-numbers, even though most of the genome remained stable. Two patients displayed major copy-number profile changes during therapy. Our analysis revealed ctDNA-detectable subclonal selection resulting from both surgical operations and chemotherapy. Overall, longitudinal ctDNA data showed acquired and diminished CNAs at relapse when compared to pre-treatment samples. These results highlight the importance of genomic profiling during treatment as well as underline the usability of ctDNA.

B-150 Impact of Clinical Catastrophic Events on Individual Reference Values for 20 Analytes: Results of a Six-Measurement Study.

Abstract Reference values are an essential aspect of clinical laboratory testing, providing a basis for comparison of results against established norms for specific patient populations. These reference values are used to evaluate diagnostic test results, monitor disease progression, and assess treatment effectiveness. The accuracy and reliability of these values are crucial to the diagnosis and treatment of disease and illness and also important in the monitoring of disease progression and treatment effectiveness. By tracking changes in test results over time, healthcare providers can assess the effectiveness of treatments and make adjustments as needed. This information is critical in the management of chronic conditions such as diabetes and hypertension. Despite their importance, reference values can be subject to variability due to a variety of factors. These include differences in laboratory testing procedures, variations in patient populations, and differences in the methods used to establish reference ranges. To address these issues, clinical laboratories can use individual references calculated based on previous test results. Nevertheless, individual reference values can be subjected to pathophysiological alterations that can modify the values of specific analytes. The aim of this study was to investigate the impact of a clinical catastrophic event, specifically troponin levels above 1000, on the calculation of individual reference values for 21 analytes. Six measurements were taken before and after the event from a sample of 5 to 450 patients. The results showed that the mean and covariance coefficient of the majority of the analytes remained unchanged despite the presence of the clinical event. Applying a Wilcoxon test to the mean before and after the event 10 out of the 21 analytes differ significantly before and after the event. These analytes included glucose, BNP, chloride, gamma GT, hematocrit, hemoglobin, potassium, C-reactive protein and urea. The mean and covariance of the remaining 11 analytes, which included platelets, creatinine, alkaline phosphatase, magnesium, sodium, AST, ALT, TSH, fibrinogen, prothrombin time, and activated partial thromboplastin time (aPTT), were not significantly impacted by the clinical event. These results suggest that despite the presence of a clinical catastrophic event, individual reference values can still be calculated for the majority of the analytes. This is important for the accurate interpretation of clinical laboratory test results, especially in the presence of acute illnesses or injuries. However, caution should be exercised when interpreting results for the three analytes that were significantly impacted by the event. Further studies are needed to determine if similar results can be obtained for other clinical catastrophic events and analytes.

Highly sensitive and rapid point-of-care testing for HIV-1 infection based on CRISPR-Cas13a system

BackgroundHuman immunodeficiency virus type one (HIV-1) is the leading cause of acquired immunodeficiency syndrome (AIDS). AIDS remains a global public health concern but can be effectively suppressed by life-long administration of combination antiretroviral therapy. Early detection and diagnosis are two key strategies for the prevention and control of HIV/AIDS. Rapid and accurate point-of-care testing (POCT) provides critical tools for managing HIV-1 epidemic in high-risk areas and populations.MethodsIn this study, a POCT for HIV-1 RNA was developed by CRISPR-Cas13a lateral flow strip combined with reverse transcriptase recombinase-aided amplification (RT-RAA) technology, the results can be directly observed by naked eyes.ResultsMoreover, with the degenerate base-binding CRISPR-Cas13a system was introduced into the RT-RAA primer designing, the technology developed in this study can be used to test majority of HIV-1 RNA with limit of detection (LOD) 1 copy/μL, while no obvious cross-reaction with other pathogens. We evaluated this method for detecting HIV-1 RNA of clinical samples, the results showed that the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were 91.81% (85.03- 96.19%), 100% (92.60–100%), 100% (96.41–100%), 39.14% (25.59–54.60%) and 92.22% (86.89–95.88%), respectively. The lowest viral load detectable by this method was 112copies/mL.ConclusionAbove all, this method provides a point-of-care detection of HIV-1 RNA, which is stable, simple and with good sensitivity and specificity. This method has potential to be developed for promoting early diagnosis and treatment effect monitoring of HIV patients in clinical.

P11.07.A PERFUSION-MRI BASED DIFFERENTIATION BETWEEN EARLY TUMOR PROGRESSION AND PSEUDOPROGRESSION IN GLIOBLASTOMA AND ITS USE IN CLINICAL PRACTICE

Abstract BACKGROUND Post-gadolinium MRI is considered the mainstay of radiological monitoring of treatment effects in patients with a glioblastoma. However, the radiotherapy(RT)-induced abnormality, pseudoprogression, is difficult to distinguish from real tumor growth. Perfusion MRI (pMRI), including Arterial Spin Labeling (ASL) and Dynamic Susceptibility Contrast (DSC), may help in this differentiation. Evaluation of RT effects is usually discussed during multidisciplinary team meetings (MDTM), after which a decision regarding (dis)continuation of anti-tumor treatment is made. It is currently unknown whether pMRI impacts such treatment decisions. This study evaluated how accurate pMRI and the MDTM are in distinguishing tumor progression from pseudoprogression in glioblastoma. MATERIAL AND METHODS Population and outcome: Glioblastoma patients who received postoperative RT were retrospectively included from 2015 to 2020. ASL, DSC, FLAIR and post-gadolinium 3D-T1 at 3 months post-RT were visually scored for probability of radiological tumor progression. These radiological scores, as well as the outcome of MDTM, were compared to the final outcome (i.e. tumor progression or pseudoprogression) set at 9 months after RT initiation. Statistical analysis: Diagnostic accuracy of pMRI, conventional MRI and MDTM was assessed by 2x2 tables, sensitivity and specificity (including AUC values). In case the MDTM was inconclusive, subsequent analysis was used to determine whether pMRI has additional value. A multivariable logistic regression model was constructed to assess which clinical parameters (age, surgery type, IDH mutation status, MGMT methylation status, KPS score, chemotherapy and pMRI evaluation) were associated with the outcome of the MDTM assessment. RESULTS Sixty-five patients with a glioblastoma met the inclusion criteria (40 male, mean age 60+/-13 years, median KPS of 90). For all METHODS , the sensitivity for detecting true disease progression was poor to moderate (32-62%). Although sensitivity was higher when adding pMRI to conventional imaging (56% versus 32%), specificity was lower (80% versus 93%). AUC values were comparable (range 0.63-0.74), but highest for MDTM evaluation (0.74). For the 26% of patients where MDTM was inconclusive, pMRI shows increased sensitivity compared to conventional MRI in detecting tumor progression (respectively 36% versus 0%). The multivariable regression analysis showed significant associations for KPS score (OR = 0.84 (95% CI: 0.77-0.91)) and radiological assessment based on pMRI with MDTM outcome (OR = 0.09 (95% CI: 0.02-0.52)). CONCLUSION This study shows that perfusion MRI has added value for detection of tumor progression within the MDTM assessment in clinical decision-making for glioblastomas, especially when the MDTM outcome is uncertain. For this decision, the role of perfusion MRI and the KPS score are most important.

Bias in Laboratory Medicine: The Dark Side of the Moon.

Physicians increasingly use laboratory-produced information for disease diagnosis, patient monitoring, treatment planning, and evaluations of treatment effectiveness. Bias is the systematic deviation of laboratory test results from the actual value, which can cause misdiagnosis or misestimation of disease prognosis and increase healthcare costs. Properly estimating and treating bias can help to reduce laboratory errors, improve patient safety, and considerably reduce healthcare costs. A bias that is statistically and medically significant should be eliminated or corrected. In this review, the theoretical aspects of bias based on metrological, statistical, laboratory, and biological variation principles are discussed. These principles are then applied to laboratory and diagnostic medicine for practical use from clinical perspectives.

Use of gadolinium-based contrast agents in multiple sclerosis: a review by the ESMRMB-GREC and ESNR Multiple Sclerosis Working Group.

Magnetic resonance imaging (MRI) is the most sensitive technique for detecting inflammatory demyelinating lesions in multiple sclerosis (MS) and plays a crucial role in diagnosis and monitoring treatment effectiveness, and for predicting the disease course. In clinical practice, detection of MS lesions is mainly based on T2-weighted and contrast-enhanced T1-weighted sequences. Contrast-enhancing lesions (CEL) on T1-weighted sequences are related to (sub)acute inflammation, while new or enlarging T2 lesions reflect the permanent footprint from a previous acute inflammatory demyelinating event. These two types of MRI features provide redundant information, at least in regular monitoring of the disease. Due to the concern of gadolinium deposition after repetitive injections of gadolinium-based contrast agents (GBCAs), scientific organizations and regulatory agencies in Europe and North America have proposed that these contrast agents should be administered only if clinically necessary. In this article, we provide data on the mode of action of GBCAs in MS, the indications of the use of these agents in clinical practice, their value in MS for diagnostic, prognostic, and monitoring purposes, and their use in specific populations (children, pregnant women, and breast-feeders). We discuss imaging strategies that achieve the highest sensitivity for detecting CELs in compliance with the safety regulations established by different regulatory agencies. Finally, we will briefly discuss some alternatives to the use of GBCA for detecting blood-brain barrier disruption in MS lesions. CLINICAL RELEVANCE STATEMENT: Although use of GBCA at diagnostic workup of suspected MS is highly valuable for diagnostic and prognostic purposes, their use in routine monitoring is not mandatory and must be reduced, as detection of disease activity can be based on the identification of new or enlarging lesions on T2-weighted images. KEY POINTS: • Both the EMA and the FDA state that the use of GBCA in medicine should be restricted to clinical scenarios in which the additional information offered by the contrast agent is required. • The use of GBCA is generally recommended in the diagnostic workup in subjects with suspected MS and is generally not necessary for routine monitoring in clinical practice. • Alternative MRI-based approaches for detecting acute focal inflammatory MS lesions are not yet ready to be used in clinical practice.