Diagnostic Limitations Research Articles

Significance and limitations of routine p16/Ki-67 immunohistochemistry as a diagnostic tool for high-grade squamous intraepithelial lesions of the uterine cervix.

To evaluate the diagnostic utility and limitations of routine p16 and Ki-67 immunohistochemistry (IHC) in detecting high-grade squamous intraepithelial lesions (HSILs) in the uterine cervix. We reviewed 2,061 cervical biopsy records, including 271 morphologically indeterminate squamous lesions, evaluated using p16/Ki-67 IHC for HSIL detection or exclusion. HSIL was diagnosed based on p16 positivity and a high Ki-67 labeling index (Ki-LI). In cases that remained inconclusive after IHC, follow-up histological and/or cytological outcomes were assessed. p16/Ki-67 IHC established a definitive diagnosis of either HSIL or non-HSIL in 74.2% (201/271) of morphologically indeterminate cases, whereas 25.8% (70/271) remained inconclusive. p16/Ki-67 IHC contributed to the diagnosis of HSIL in 120 cases, representing 11.9% (120/1,011) of all HSILs cases and 44.3% (120/271) of morphologically indeterminate cases. Among the 70 inconclusive cases, 58 had available follow-up data, of which 22 were subsequently diagnosed with HSIL, including 12 within 1 month of the initial biopsy. HSIL outcomes were more frequent in cases with suspicious HSIL on the initial biopsy (66.7 [12/18]). Based on the p16/Ki-LI status, patients with HSIL outcomes were categorized into three groups: p16-positive/low Ki-LI (54.2 [13/24]), p16-negative/high Ki-LI (50.0 [5/10]), and p16-negative/low Ki-LI (16.7 [4/24]). Multiple comparisons revealed a significant difference between the p16-positive/low Ki-LI and p16-negative/low Ki-LI groups (Benjamini-Yekutieli adjusted P=0.0435), whereas no significant difference was found between other groups. IHC using p16/Ki-67 significantly improved the diagnostic performance for HSIL. In cases that remain inconclusive after IHC, IHC-based risk stratification offers a valuable approach for surveillance, thus mitigating delays in HSIL diagnosis.

Cat scratch disease in children with nocturnal fever: A case report

BACKGROUND Cat scratch disease (CSD) is the most common human infection caused by Bartonella henselae (B. henselae ). The main manifestation is self-limited lymphadenopathy that primarily affects adolescents, and typically resolves without treatment within 2-4 months. However, individuals with compromised immune systems or immunodeficiency require specific antibacterial therapy following diagnosis. Due to its low incidence, nonspecific clinical manifestations, and diagnostic limitations, this condition often poses challenges for clinicians in terms of missed diagnoses and misdiagnoses. CASE SUMMARY The child was ultimately diagnosed with CSD. The primary manifestations included nocturnal fever, enlargement of lymph nodes in the neck, axilla and groin, and suspected brucellosis; however, both brucellosis tests conducted during the course of the illness yielded negative results. Bone marrow cytology indicated stimulated proliferation. Lymph node biopsy indicated hyperplasia of lymphoid tissue in the cervical lymph nodes (right), with combined immunohistochemical findings indicating reactive hyperplasia. Immunohistochemical analysis revealed CD20 B (+), CD3 T (+), BCL-6 (+), and BCL-2 (). CD21 FDC networks were present and Ki67 expression in the germinal center was ~80%. Blood next-generation sequencing indicated B. henselae sequence number was 3. Serological test results demonstrated positive antibody response to B. henselae IgG (+), B. henselae IgM (+), Bartonella quintana (B. quintana ) IgG () and B. quintana IgM (), and the final diagnosis was CSD. CONCLUSION In patients presenting with fever at night and swollen lymph nodes of unknown origin, CSD should be considered.

FIGO-GCH joint consensus statement on the current status and recommendations for the use of blind intrauterine procedures in the evaluation and management of women withsuspected intrauterine pathologies.

Historically, blind intrauterine procedures such as dilation and curettage (D&C) and blind endometrial biopsies have been the primary approach for diagnosing and managing intrauterine pathologies. However, these techniques lack direct visualization, leading to diagnostic limitations, incomplete treatment, and increased complication rates. Despite substantial advances in hysteroscopic technology, including high-definition imaging and minimally invasive instruments, blind procedures remain widely used. This paper examines the limitations of blind intrauterine procedures, underscoring the advantages of hysteroscopy, which provides real-time visualization and allows for more accurate, targeted interventions. With the adoption of the "See and Treat" philosophy, hysteroscopy enables nearly 90% of procedures to be performed in an office setting, enhancing both patient convenience and outcomes. FIGO and GCH advocate for the gradual replacement of blind procedures with hysteroscopic approaches whenever feasible, noting that hysteroscopy improves diagnostic accuracy, reduces risks, and minimizes the need for repeat interventions. Recommendations include expanding access to hysteroscopy through targeted training, especially in low- and middle-income countries, where financial and logistical barriers limit access to advanced gynecological care. Furthermore, this paper emphasizes the importance of patient-centered care, encouraging transparent counseling to support informed decision-making.

Histopathological diagnostics of infections in rheumatology

The histopathological differential diagnoses of inflammatory infectious and inflammatory noninfectious diseases of the musculoskeletal system, particularly infectious and noninfectious arthritis, soft tissue inflammation and osteomyelitis in rheumatology are presented with afocus on the differential diagnostic possibilities and limitations; however, adiverse spectrum of pathogenic mechanisms underly these diseases, which can present with similar inflammatory response patterns. This wide spectrum of inflammatory pathogenesis of infectious and noninfectious diseases includes diseases such as rheumatoid arthritis, gouty arthritis, osteomyelitis and pyoderma gangrenosum, which cannot clinically be manifested thus necessitating a histopathological clarification. In terms of tissue sampling the following general principle applies: the larger the tissue sample and the more diverse the sites of tissue extraction, the more conclusive are the histopathological diagnostics. This diagnostic approach to infections, especially in arheumatological context, is generally considered complementary and even supplementary to microbiological diagnostics. Furthermore, consideration of the virulence-resistance relationship, which can alter the inflammatory pattern, is of additional relevance. Consequently, definitive causal diagnostics are only achievable within the clinical, rheumatological, microbiological, laboratory medical and infectiological context.

Analysis of time-to-positivity data in tuberculosis treatment studies: Identifying a new limit of quantification.

The BACTEC Mycobacteria Growth Indicator Tube (MGIT) machine is the standard globally for detecting viable mycobacteria in patients' sputum. Samples are observed for no longer than 42 days, at which point the sample is declared "negative" for tuberculosis (TB). This time to detection of bacterial growth, referred to as time-to-positivity (TTP), is increasingly of interest not solely as a diagnostic tool, but as a continuous biomarker wherein change in TTP can be used for comparing the bactericidal activity of different TB treatments. However, as a continuous measure, there are oddities in the distribution of TTP values observed, particularly at higher values. We explored whether there is evidence to suggest setting an upper limit of quantification for modeling purposes (ULOQM) lower than the diagnostic limit of detection (LOD) using data from several TB-PACTS randomized clinical trials and PanACEA MAMS-TB. Across all trials, less than 7.1% of weekly samples returned TTP measurements between 25 and 42 days. Further, the relative absolute prediction error (%) was highest in this range. When modeling with ULOQMs of 25 and 30 days, estimator precision improved for 23 of 25 regimen-level slopes compared to models using the LOD. Discrimination between regimens based on Bayesian posteriors also improved. While TTP measurements between 25 days and the diagnostic LOD may be important for diagnostic purposes, TTP values in this range may not contribute meaningfully to its use as a quantitative measure, particularly when assessing treatment response, and may lead to under-powered clinical trials.

Advancing Diagnostics: The Role of Ultrasound and MR Imaging in Evaluating Musculotendinous Pathologies of the Shoulder Joint – A Comprehensive Literature Review

Musculotendinous pathologies of the shoulder joint are a common source of pain and functional impairment, often requiring precise imaging for accurate diagnosis and management. This review explores the roles of ultrasound (US) and magnetic resonance imaging (MRI) in evaluating these conditions, focusing on their diagnostic strengths, limitations, and clinical applications. Ultrasound offers dynamic, real-time assessment with high accuracy for superficial structures, making it a cost-effective option for evaluating rotator cuff tears and tendinopathies. MRI, on the other hand, is the gold standard for comprehensive imaging of deep soft tissues, labral injuries, and subtle intra-articular abnormalities. Recent advances in both modalities, including AI-powered ultrasound and faster MRI sequences, have enhanced diagnostic capabilities. This review synthesizes evidence from the past decade, comparing the sensitivity, specificity, and cost-effectiveness of US and MRI while discussing scenarios where their integration can provide the most benefit. The findings emphasize the need for modality selection tailored to clinical presentations, the expertise of practitioners, and healthcare resource availability. Future research should aim to standardize imaging protocols and explore innovative multimodal approaches to improve diagnostic accuracy further.

Progress in diagnosis of peri-implantitis

Peri-implantitis is one of the most common biological complications after implant restoration which is difficult to be cured. Early and correct diagnosis is of great significance for the prevention and treatment of peri-implantitis. Although there have been consensus reports to make guiding suggestions in diagnosis, the diagnostic criteria are not uniform, resulting in many confusions. This review summarizes published consensuses on the diagnosis of peri-implantitis, analyzes the diagnostic values and limitations of traditional examination methods, and summarizes the recent advances in examination methods for peri-implant soft and hard tissues, aiming to provide a reference for clinical diagnosis of peri-implantitis.

Liver Transplant Beyond the Milan Criteria: Distant Metastases of Hepatocellular Carcinoma (Part II)

Liver transplant is one of the most effective ways to treat hepatocellular carcinoma (HCC). Thanks to the implementation of the Milan criteria, developed almost 30 years ago, 5-year survival rates for patients who underwent a transplant for HCC increased and reached the rates for patients with nontumor indications. Despite the emergence of alternative stratification systems, extrahepatic metastases remain a key contraindication to a liver transplant. Nevertheless, there have been reported cases of liver transplants in spite of the contraindication not only in times of diagnostic limitations but also in the 21st century.We have previously reported our own case of a patient who underwent a liver transplant in spite of pulmonary lesions, which postoperatively were found to be HCC metastases. In this part of the review, we discuss similar cases from the literature.If metastatic lesions are successfully treated, a related donor is available, and other modalities are seen as less preferable in terms of the disease prognosis, a liver transplant may be considered an appropriate way to prolong the patient’s life, although such approach should not be recommended for widespread use.

Abstract IA004: Early cancer dissemination: Circulating tumor cells in ductal carcinoma in situ patients

Abstract Raised awareness about the importance of early breast cancer diagnostics has led to an increased detection rate of ductal carcinoma in situ (DCIS) through mammographic screening. DCIS, often termed as 'Stage 0' carcinoma, is characterized by neoplastic cells confined within the basement membrane. Despite the significant treatment efforts for most DCIS patients, the 20-year breast cancer mortality rate post-diagnosis, with or without treatment, remains at 3.3%. To deepen the understanding of breast cancer oncogenesis, recent studies have highlighted the clonal diversity within the DCIS tumor microenvironment and the presence of disseminated tumor cells in DCIS patients. Nonetheless, significant gaps persist in identifying diagnostic characteristics that predict which DCIS patients are more likely to experience progression or recurrence. Ultimately, this project aims to enhance DCIS patient stratification through the high-throughput isolation and analysis of circulating biomarkers. In this study, we establish a novel workflow that addresses the limitations of traditional tissue-based diagnostics by transitioning to liquid biopsies. This research not only builds upon emerging evidence of early breast cancer cell dissemination during carcinogenesis but also explores the utility of circulating tumor cells (CTCs) as biomarkers in DCIS. The use of the labyrinth, a high-throughput inertial microfluidic device, has shown success in isolating CTCs based on their larger size relative to white blood cells. Unlike antigen- based isolation methods, inertial microfluidic devices can capture heterogeneous CTCs with varying surface proteins. Leveraging this technology, we successfully isolated and identified CTCs in DCIS patients. Furthermore, single-cell RNA sequencing of the isolated DCIS CTCs allowed us to identify prognostically significant signatures. Overall, our study presents a workflow capable of identifying characteristics associated with a greater risk of progression, thus contributing valuable insights into the stratification and management of DCIS patients. Citation Format: Sunitha Nagrath, Neha Nagpal, Brittany Rupp, Yan Hong, Fariba Behbod, Max Wicha. Early cancer dissemination: Circulating tumor cells in ductal carcinoma in situ patients [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr IA004.

Clarifying the place of p300 in the empirical structure of psychopathology over development.

Psychophysiology can help elucidate the structure and developmental mechanisms of psychopathology, consistent with the Research Domain Criteria initiative. Cross-sectional research using categorical diagnoses indicates that P300 is an electrocortical endophenotype indexing genetic vulnerability to externalizing problems. However, current diagnostic systems' limitations impede a precise understanding of risk. The Hierarchical Taxonomy of Psychopathology (HiTOP) overcomes these limitations by delineating reliable dimensions ranging in specificity from broad spectra to narrow syndromes. The current study used a HiTOP-aligned approach to clarify P300's associations with a higher-order externalizing factor versus syndrome-specific manifestations within externalizing and internalizing spectra during middle and late adolescence. Participants from the Minnesota Twin Family Study's Enrichment Sample contributed psychophysiological and clinical data at age 14 (N = 930) and follow-up clinical data at age 17 (N = 913). Blunted target P300 at age 14 was selectively associated with externalizing as manifested at age 17 at the superspectrum level (rather than specific externalizing syndromes). Unlike in prior work, target P300 amplitude was positively associated with age 17 depressive symptoms (once controlling for standard stimuli). No association was observed with lifetime symptoms of childhood externalizing or depression evident by age 14. The results indicate that blunted target P300 elucidates specific risk for the development of late-adolescent/young-adult expressions of general externalizing, over and above symptoms evident by middle adolescence. Additionally, the findings speak to the synergistic utility of studying HiTOP-aligned dimensions using multiple measurement modalities to build a more comprehensive understanding of the development of psychopathology. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Histology Agnostic Drug Development: An Updated Review.

Recent advancements in oncology have led to the development of histology-agnostic therapies, which target genetic alterations irrespective of the tumor's tissue of origin. This review aimed to provide a comprehensive update on the current state of histology-agnostic drug development, focusing on key therapies, including pembrolizumab, larotrectinib, entrectinib, dostarlimab, dabrafenib plus trametinib, selpercatinib, trastuzumab deruxtecan, and reprotrectinib. We performed a detailed analysis of each therapy's mechanism of action, clinical trial outcomes, and associated biomarkers. The review further explores challenges in drug resistance, such as adaptive signaling pathways and neoantigen variability, as well as diagnostic limitations in identifying optimal patient populations. While these therapies have demonstrated efficacy in various malignancies, significant hurdles remain, including intratumoral heterogeneity and resistance mechanisms that diminish treatment effectiveness. We propose considerations for refining trial designs and emerging biomarkers, such as tumor neoantigen burden, to enhance patient selection. These findings illustrate the transformative potential of histology-agnostic therapies in precision oncology but highlight the need for continued research to optimize their use and overcome existing barriers.

Comparative imaging modalities for diagnosing rotator cuff injuries

Rotator cuff injuries are a significant cause of shoulder pain and dysfunction, with their prevalence increasing with age. Diagnosing these injuries accurately is crucial for determining appropriate treatment strategies. Various imaging modalities, such as high-resolution ultrasonography (HRUS), magnetic resonance imaging (MRI), and magnetic resonance arthrography (MRA), play a pivotal role in identifying rotator cuff injuries. MRI, considered the gold standard, offers detailed insights into tendon degeneration, partial tears, and full-thickness tears. Meanwhile, HRUS is favored for its cost-effectiveness, non-invasive nature, and real-time dynamic assessments. This review compares these imaging techniques, highlighting their diagnostic accuracy, strengths, and limitations in the context of rotator cuff injuries. Although MRI provides comprehensive information on tendon pathology and associated conditions like muscle atrophy, HRUS remains a valuable tool due to its accessibility and accuracy in diagnosing both partial and full-thickness tears. Understanding the comparative efficacy of these imaging modalities is essential for clinicians to make informed decisions about patient management.

Comorbid mental illness and intellectual disability: impact on employment

Objectives In the general population, studies have revealed that mental health concerns negatively impact employment. Research has also begun to reveal similar negative employment outcomes among individuals with an intellectual disability and co-occurring mental health disorder. This study sought to expand upon these findings and examine whether specific diagnoses relate to inclusive employment. Methods We conducted Chi-square tests to examine if reported diagnoses and challenging behaviors related to paid community employment among 378 individuals with an intellectual disability in Pennsylvania who participated in the Independent Monitoring for Quality program. We selected participants from a statewide database compiled via stratified random sampling and structured interview. Results We found statistically significant differences in community-based employment rates between those with and without a mood disorder (χ 2 (2) = 6.07; p = 0.01) and behavior challenges (χ 2 (2) = 5.04; p = 0.03). Anxiety disorders approached statistical significance (χ 2 (2) = 3.73; p = 0.05). Conclusions The significant relationships between employment and mental health is consistent with studies in the general population. We discuss diagnostic challenges and limitations of this study, proposing future research explore a transdiagnostic approach to targeting mental health concerns for those with an intellectual disability.

Outer membrane protein C is a protective and unique vaccine antigen against Shigella flexneri 3a

The anti-Shigella vaccine is one of the WHO’s top priorities. Every year the disease kills more than 200,000 people worldwide and poses a serious threat to children under 5 years of age and the elderly. Increasing antibiotic resistance and limitations in diagnostics emphasize the need to develop an effective vaccine. Recent research and clinical trials report multiple approaches used in Shigella-vaccine development. However, despite the efforts of researchers, pharmaceutical companies and health care organizations, there is no licensed vaccine against shigellosis available to the community. Here, we expressed, broadly characterized and demonstrated the protective properties of outer membrane protein C as an effective molecule serving as a universal antigen for Shigella vaccine. Most of the current approaches to the development of Shigella vaccine are based on the polysaccharide antigens, which are serotype specific and have always been challenging in terms of their high specificity, targeting the most exposed surface antigens identified for certain Shigella serotypes. Here, we confirm immunogenic and protective properties of the recombinant OmpC protein, which protects mice against a lethal dose of a virulent strain 2 weeks after active immunization.

Detection of anti-leptospiral antibodies using recombinant ErpY-like lipoprotein based latex agglutination test for serodiagnosis of animal leptospirosis.

Precise and timely diagnosis is essential to prevent severe outcomes of leptospirosis in humans and animals. Existing diagnostic methods face challenges and limitations, underscoring the need for novel, field-applicable screening, and diagnostic tests/assays. This study evaluates the diagnostic utility of a recombinant ErpY-like lipoprotein (rErpY-LIC11966) in a latex agglutination test (LAT) for diagnosis of animal leptospirosis. The ErpY gene sequence from Leptospira interrogans serovar Pomona, excluding the signal peptide, was amplified, cloned into the pETite vector, and expressed in Escherichia coli. The expressed rErpY (∼16kDa) was characterized by Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis and Western blot using Leptospira-specific standard sera. To assess the diagnostic potential of rErpY, Ni-NTA affinity-purified protein was used to sensitize latex-coated beads (0.8µm colour beads), which were then employed in the LAT for standardization and optimization with standard positive and negative sera. For evaluation, the rErpY-LAT was tested on serum samples from 177 suspected animal cases and compared to the microscopic agglutination test. It showed a relative diagnostic sensitivity of 90.6%, a specificity of 89.1%, and an overall accuracy of 90%. This study proposes rErpY-LAT as a field testing/screening diagnostic tool for preliminary serodiagnosis of leptospirosis, highlighting the potential of recombinant protein-based assays to address current diagnostic challenges.

Concordance Between Platelet Expression Assay (PEA) and Serotonin Release Assay (SRA) in Heparin-Induced Thrombocytopenia: Implications for Diagnostic Accuracy and Laboratory Test Utilization

Abstract Introduction The Serotonin Release Assay (SRA) serves as the gold standard functional assay for heparin-induced thrombocytopenia (HIT) diagnosis at our institution. The present turnaround time (TAT) for SRA results ranges from 4-5 days, occasionally extending beyond 8 days, given outsourcing to a reference laboratory. Recently, an alternative functional assay, the Platelet Expression Assay (PEA), has been introduced. The PEA detects platelet activation through p-selectin expression by flow cytometry, with a reported sensitivity of 100% and specificity of 95% for HIT. The PEA is also a send-out test, and thus has similar TAT and cost profiles as the SRA, but with potential to transition into an in-house assay in the future. Herein, we sought to determine the concordance of the PEA and SRA for the detection and diagnosis of HIT within our patient population. Methods A retrospective review was conducted on all cases in which a HIT ELISA (screening immunoassay) was performed by the Special Coagulation Laboratory during a one-year period. A 4Ts score was calculated if not already documented by chart review. In a subset analysis, specimens with a positive screening ELISA were concurrently tested by both SRA and PEA to compare performance. Results Of the 1341 cases, a 4Ts score was calculated and found to be less than 4 for 30-50% of cases. A total of 490 cases were sent out for SRA, of which 49 (10%) returned positive results. In a subset analysis of 20 samples from 14 patients, all with positive ELISAs, results revealed concordance between the SRA and PEA for all but one sample (19/20, 95%). Specifically, three successive samples from one patient had [negative, negative, positive] results for SRA, and [negative, positive, positive] results for PEA, respectively. This discordant result suggests a potential difference in sensitivity between the two assays. Further subset analysis focused on an additional 13 samples from 10 patients, all with SRA-positive results. Only 8 samples were concordant (8/13, 62%). One case showed a negative PEA and presumed false positive SRA, given the clinical history, while 4 samples showed likely true positive SRA results, given strength of ELISA results and 4Ts score, but were negative by PEA. Conclusions The lack of adherence to the 4Ts score algorithm to drive laboratory test utilization resulted in unnecessary ELISA and functional assay testing, potentially resulting in increased costs and false positive results. This result underscores the need for vigilance in assessing and refining diagnostic strategies. Additionally, our discordant findings in the subset analysis underscore the importance of evaluating the concordance and discordance between SRA and PEA results, providing insights into the diagnostic accuracy and potential limitations of each assay in identifying HIT.

Diagnostic Accuracy of Beta-2 Transferrin Gel Electrophoresis for Detecting Cerebrospinal Fluid Rhinorrhea.

Unilateral thin clear rhinorrhea (UTCR) may represent a variety of pathologies including cerebrospinal fluid (CSF) rhinorrhea. Beta-2 transferrin (B2Tf) gel electrophoresis (GE) has become the preferred testing modality due to reportedly high sensitivity (87%-100%) and specificity (71%-100%). However, there have been relatively few studies assessing its diagnostic accuracy. The purpose of this single-institution study was to determine the accuracy of B2Tf GE in detecting CSF rhinorrhea. A single-center retrospective review was conducted from 2016 and 2024 for all patients who presented with UTCR and underwent B2Tf GE. Institutional review board approval was obtained. The gold standard for diagnostic confirmation of true and false positives (TP, FP) as well as false negatives (FN) was endoscopic exploration. The gold standard for true negative (TN) was response to medical therapy. A total of 105 patients underwent 149 B2Tf GE tests. 40 (38.1%) patients were diagnosed with CSF rhinorrhea. Of the 149 B2-Tf GE tests, there were 51 TPs, 72 TNs, 20 FPs, and 6 FNs yielding 89.5% sensitivity, 78.3% specificity, 71.8% positive predictive value, and 92.3% negative predictive value, respectively. Of the false results the most common causes for error were purulent sinusitis (n = 6, 23.1%), possible mucous contamination from nose-blowing during collection (n = 3, 11.5%), patient collection error (n = 3, 11.5%), and blood contamination (n = 1, 3.8%). Although these single-institutional data demonstrate test accuracy within ranges previously reported in the literature, they also demonstrate diagnostic limitations. Future studies should explore reasons for erroneous B2Tf GE results and how these may change clinical decision-making. IV Laryngoscope, 2024.

Artificial intelligence-enhanced detection of subclinical coronary artery disease in athletes: diagnostic performance and limitations.

This study evaluates the diagnostic performance of artificial intelligence (AI)-based coronary computed tomography angiography (CCTA) for detecting coronary artery disease (CAD) and assessing fractional flow reserve (FFR) in asymptomatic male marathon runners. We prospectively recruited 100 asymptomatic male marathon runners over the age of 45 for CAD screening. CCTA was analyzed using AI models (CorEx and Spimed-AI) on a local server. The models focused on detecting significant CAD (≥ 50% diameter stenosis, CAD-RADS 3, 4, or 5) and distinguishing hemodynamically significant stenosis (FFR ≤ 0.8) from non-significant stenosis (FFR > 0.8). Statistical analysis included sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy. The AI model demonstrated high sensitivity, with 91.2% for any CAD and 100% for significant CAD, and high NPV, with 92.7% for any CAD and 100% for significant CAD. The diagnostic accuracy was 73.4% for any CAD and 90.4% for significant CAD. However, the PPV was lower, particularly for significant CAD (25.0%), indicating a higher incidence of false positives. AI-enhanced CCTA is a valuable non-invasive tool for detecting CAD in asymptomatic, low-risk populations. The AI model exhibited high sensitivity and NPV, particularly for identifying significant stenosis, reinforcing its potential role in screening. However, limitations such as a lower PPV and overestimation of disease indicate that further refinement of AI algorithms is needed to improve specificity. Despite these challenges, AI-based CCTA offers significant promise when integrated with clinical expertise, enhancing diagnostic accuracy and guiding patient management in low-risk groups.

B-104 Correlation of Anti-Centromere Antibodies (ACA) Detection by Indirect Immunofluorescence (IFA) on HEp-2 Cells and by ELISA Demonstrates High Concordance but Highlights Advantage of IFA

Abstract Background Anti-centromere antibodies (ACA), a type of anti-nuclear antibody (ANA) first identified as a discrete speckled pattern on indirect immunofluorescence assay (IFA), are a hallmark of systemic sclerosis (SSc), especially in its limited cutaneous form (lcSSc) or CREST (calcinosis, Raynaud’s, esophageal dysmotility, sclerodactyly and telangiectasia). These mitosis-related autoantibodies mainly recognize three centromere proteins (CENP), CENP-A, CENP-B, and CENP-C, that comprise the kinetochore important to chromosome segregation, but more recently, at least three other CENP antigens have been identified (CENP-D, CENP-E and CENP-F). Anti-CENP-B is considered the main autoantibody, and many, if not most, ELISA utilize recombinant CENP-B such that antibodies to CENP antigens other than CENP-B are not detected. Here, an ELISA using both CENP-B and CENP-A is compared to the reference method, HEp-2 cell IFA, highlighting its high, but still less than 100%, sensitivity due to multiple centromere subcomponents. Methods Anti-centromere antibodies are determined in patient serum using the reference method, IFA on the HEp-2 cell substrate (Sprinter XL/EUROpattern®, Euroimmun, NJ) which is also the current method for standalone ACA testing as well as screening by selected ANA profiles designed for the rheumatology specialist. Here ACA IFA- positive and negative serum samples were further analyzed by enzyme immunosorbent assay (ELISA) utilizing recombinant CENP-A and CENP-B (QuantaLyzer® 3000, Werfen, CA). Results When compared, samples between ACA pattern by HEp-2 cell IFA and anti- centromere antibodies by ELISA yielded an agreement of 93.2%. McNemar’s Test Chi Square of p>0.999, with a relative sensitivity of 89.7% and a specificity of 100.0%. Conclusions This study demonstrated very high concordance between ELISA and accurate ACA pattern identification on HEp-2 IFA. The ELISA studied here identifies autoantibodies to both CENP-A and CENP-B where many other ELISA identify only anti-CENP-B. Although ACA are relatively specific for SSc, they have also been reported in systemic lupus erythematosus (SLE), primary biliary cholangitis (PBC), rheumatoid arthritis (RA), Sjogren Syndrome, Raynaud's phenomenon and in cancer in individuals with or without evidence of systemic autoimmune rheumatic disease (SARD). Of note, many other commercially available ELISA for anti-centromere antibodies identify only anti-CENP-B, but there at least four other known CENP antigen targets for autoantibodies causing centromere pattern on IFA. Furthermore, almost all laboratories use the ELISA for ACA on ANA panel (or other connective tissue disease) screening. Hence, it should be duly noted that these testing strategies will not detect autoantibodies to all anti-centromere antibodies. Only specialized ANA profiles designed for the difficult-to-diagnose autoimmune patient begin screening using the IFA method for anti-centromere and therefore, are capable of detecting autoantibodies to all CENP antigens. Laboratorians should advise clinicians of these diagnostic limitations especially as our knowledge about centromere subcomponents and their clinical associations increases.

Babesiosis: Analysis of the Evidence for Infections in the United Kingdom.

Human babesiosis is caused when erythrocytes are invaded by Babesia. Infection can occur from the bite of an infected tick, blood transfusion or congenitally. Issues related to the infecting species, symptomology and testing technology are discussed and the implications of accurate incidence and prevalence of the disease discussed. Human babesiosis is considered to be relatively rare in the UK. With a considerable number of non-specific symptoms and diagnostic testing limitations, it is probable that true positives are being missed. Based on co-infection data for Borrelia and Babesia from Rhode Island and Connecticut, and on Borrelia seropositivity data from northeastern France, the prevalence of babesiosis in those aged under 35 years, 35 to 44 years, 45 to 54 years and 55 years and over would be expected to be 0.6%, 1.8%, 2.8% and 3.5%, respectively. Based on the prevalence of infections in ticks and canines and a disease model previously published, it is estimated that the UK incidence of human babesiosis is likely to be approximately 18,500 cases per year.