MRI and CT imaging characteristics in parotid tumors with false-negative fine-needle aspirations.

BACKGROUNDS: Preoperative imaging, particularly with magnetic resonance imaging (MRI) and computed tomography (CT) scans, plays a crucial role in distinguishing between benign and malignant parotid gland tumors, while the reliability of Ultrasound-Guided Fine Needle Aspiration (FNA) in diagnosing these masses remains a topic of debate. METHODS: This two-center retrospective analysis was conducted on 347 patients with parotid gland tumors who had FNA and preoperative imaging (CT or MRI). All patients underwent surgery and final histopathological examination was available, along with complete medical records between January 2008 and May 2023. RESULTS: Among the 347 patients, 318 (92%) had benign and 10 (3%) had malignant tumors based on FNA, with 19 (5%) unsatisfactory specimens. Final histological diagnosis revealed 303 (87%) benign and 44 (13%) malignant lesions, with a false-negative rate of 10.6% for FNA. Multivariate analysis identified irregular shape and invasion as independent predictors of malignancy in patient with benign or unsatisfactory FNA results. The odds ratio for irregular shape was 3.06 and for invasion was 12.73. CONCLUSION: Imaging characteristics, such as irregular shape and invasion may indicate towards malignant parotid tumors, even in patients with false-negative benign findings in FNA.

Laboratory-based molecular test alternatives to RT-PCR for the diagnosis of SARS-CoV-2 infection.

BACKGROUND: Diagnosing people with a SARS-CoV-2 infection played a critical role in managing the COVID-19 pandemic and remains a priority for the transition to long-term management of COVID-19. Initial shortages of extraction and reverse transcription polymerase chain reaction (RT-PCR) reagents impaired the desired upscaling of testing in many countries, which led to the search for alternatives to RNA extraction/purification and RT-PCR testing. Reference standard methods for diagnosing the presence of SARS-CoV-2 infection rely primarily on real-time reverse transcription-polymerase chain reaction (RT-PCR). Alternatives to RT-PCR could, if sufficiently accurate, have a positive impact by expanding the range of diagnostic tools available for the timely identification of people infected by SARS-CoV-2, access to testing and the use of resources. OBJECTIVES: To assess the diagnostic accuracy of alternative (to RT-PCR assays) laboratory-based molecular tests for diagnosing SARS-CoV-2 infection. SEARCH METHODS: We searched the COVID-19 Open Access Project living evidence database from the University of Bern until 30 September 2020 and the WHO COVID-19 Research Database until 31 October 2022. We did not apply language restrictions. SELECTION CRITERIA: We included studies of people with suspected or known SARS-CoV-2 infection, or where tests were used to screen for infection, and studies evaluating commercially developed laboratory-based molecular tests for the diagnosis of SARS-CoV-2 infection considered as alternatives to RT-PCR testing. We also included all reference standards to define the presence or absence of SARS-CoV-2, including RT-PCR tests and established clinical diagnostic criteria. DATA COLLECTION AND ANALYSIS: Two authors independently screened studies and resolved disagreements by discussing them with a third author. Two authors independently extracted data and assessed the risk of bias and applicability of the studies using the QUADAS-2 tool. We presented sensitivity and specificity, with 95% confidence intervals (CIs), for each test using paired forest plots and summarised results using average sensitivity and specificity using a bivariate random-effects meta-analysis. We illustrated the findings per index test category and assay brand compared to the WHO's acceptable sensitivity and specificity threshold for diagnosing SARS-CoV-2 infection using nucleic acid tests. MAIN RESULTS: We included data from 64 studies reporting 94 cohorts of participants and 105 index test evaluations, with 74,753 samples and 7517 confirmed SARS-CoV-2 cases. We did not identify any published or preprint reports of accuracy for a considerable number of commercially produced NAAT assays. Most cohorts were judged at unclear or high risk of bias in more than three QUADAS-2 domains. Around half of the cohorts were considered at high risk of selection bias because of recruitment based on COVID status. Three quarters of 94 cohorts were at high risk of bias in the reference standard domain because of reliance on a single RT-PCR result to determine the absence of SARS-CoV-2 infection or were at unclear risk of bias due to a lack of clarity about the time interval between the index test assessment and the reference standard, the number of missing results, or the absence of a participant flow diagram. For index tests categories with four or more evaluations and when summary estimations were possible, we found that: a) For RT-PCR assays designed to omit/adapt RNA extraction/purification, the average sensitivity was 95.1% (95% CI 91.1% to 97.3%), and the average specificity was 99.7% (95% CI 98.5% to 99.9%; based on 27 evaluations, 2834 samples and 1178 SARS-CoV-2 cases); b) For RT-LAMP assays, the average sensitivity was 88.4% (95% CI 83.1% to 92.2%), and the average specificity was 99.7% (95% CI 98.7% to 99.9%; 24 evaluations, 29,496 samples and 2255 SARS-CoV-2 cases); c) for TMA assays, the average sensitivity was 97.6% (95% CI 95.2% to 98.8%), and the average specificity was 99.4% (95% CI 94.9% to 99.9%; 14 evaluations, 2196 samples and 942 SARS-CoV-2 cases); d) for digital PCR assays, the average sensitivity was 98.5% (95% CI 95.2% to 99.5%), and the average specificity was 91.4% (95% CI 60.4% to 98.7%; five evaluations, 703 samples and 354 SARS-CoV-2 cases); e) for RT-LAMP assays omitting/adapting RNA extraction, the average sensitivity was 73.1% (95% CI 58.4% to 84%), and the average specificity was 100% (95% CI 98% to 100%; 24 evaluations, 14,342 samples and 1502 SARS-CoV-2 cases). Only two index test categories fulfil the WHO-acceptable sensitivity and specificity requirements for SARS-CoV-2 nucleic acid tests: RT-PCR assays designed to omit/adapt RNA extraction/purification and TMA assays. In addition, WHO-acceptable performance criteria were met for two assays out of 35 when tests were used according to manufacturer instructions. At 5% prevalence using a cohort of 1000 people suspected of SARS-CoV-2 infection, the positive predictive value of RT-PCR assays omitting/adapting RNA extraction/purification will be 94%, with three in 51 positive results being false positives, and around two missed cases. For TMA assays, the positive predictive value of RT-PCR assays will be 89%, with 6 in 55 positive results being false positives, and around one missed case. AUTHORS' CONCLUSIONS: Alternative laboratory-based molecular tests aim to enhance testing capacity in different ways, such as reducing the time, steps and resources needed to obtain valid results. Several index test technologies with these potential advantages have not been evaluated or have been assessed by only a few studies of limited methodological quality, so the performance of these kits was undetermined. Only two index test categories with enough evaluations for meta-analysis fulfil the WHO set of acceptable accuracy standards for SARS-CoV-2 nucleic acid tests: RT-PCR assays designed to omit/adapt RNA extraction/purification and TMA assays. These assays might prove to be suitable alternatives to RT-PCR for identifying people infected by SARS-CoV-2, especially when the alternative would be not having access to testing. However, these findings need to be interpreted and used with caution because of several limitations in the evidence, including reliance on retrospective samples without information about the symptom status of participants and the timing of assessment. No extrapolation of found accuracy data for these two alternatives to any test brands using the same techniques can be made as, for both groups, one test brand with high accuracy was overrepresented with 21/26 and 12/14 included studies, respectively. Although we used a comprehensive search and had broad eligibility criteria to include a wide range of tests that could be alternatives to RT-PCR methods, further research is needed to assess the performance of alternative COVID-19 tests and their role in pandemic management.

One Case of Abnormal Decrease of Interferon Gamma Release Assay Result Caused by Melphalan.

BACKGROUND: Interferon gamma release assay (IGRA) is an important method to detect the specific antigen of tuberculosis, which is crucial to the diagnosis of tuberculosis or potential tuberculosis infection. METHODS: We report a case of myelosuppression caused by the use of Melphalan in the treatment of multiple myeloma, resulting in an abnormal decrease in interferon gamma release assay results. RESULTS: We collected blood samples from the patient for retesting and the result of the test did not differ significantly. Upon reviewing the case, it was found that the patient's use of Melphalan treatment resulted in bone marrow suppression and extreme reduction of peripheral blood lymphocytes. Therefore, it is speculated that the abnormal decrease of the interferon gamma release assay result is caused by bone marrow suppression, which is caused by the use of Melphalan. CONCLUSIONS: When patients with multiple myeloma are treated with Melphalan, it can lead to bone marrow suppression and result in false negative interference gamma release assay results. Laboratory staff should consider the existence of such interference and communicate with clinical doctors in a timely manner.

Early Detection of Parkinson's Disease Using Deep NeuroEnhanceNet With Smartphone Walking Recordings.

With the development of digital medical technology, ubiquitous smartphones are emerging as valuable tools for the detection of complex and elusive diseases. This paper exploits smartphone walking recording for early detection of Parkinson's disease (PD) and finds that walking recording empowered by deep learning is a valid digital biomarker for early-recognizing PD patients. Specifically, the inertial sensor data is preprocessed, including normalization, scaling, and rotation, and then the processed data is fed into the proposed deep NeuroEnhanceNet. Finally, determine the individual prediction score using the PD-prone strategy and generate the detection results. The proposed deep NeuroEnhanceNet, specifically designed for inertial sensor data, can focus on both the long-term data characteristics within a single channel and the inter-channel correlations. Our method obtains a low false negative rate of 0.053 for the early detection of PD. We further analyze and compare the effectiveness of digital biomarkers captured from the walking and resting processes for early detection of PD. All the code for this work is available at: https://github.com/heyiyia/NeuroEnhanceNet.

Histidine-rich protein (hrp) 2-based RDT false-negatives and Plasmodium falciparum hrp 2 and 3 gene deletions in low, seasonal and intense perennial transmission zones in Cameroon: a cross - sectional study.

BACKGROUND: False negative rapid diagnostic tests (RDTs) accruing to the non-detection of Plasmodium falciparum histidine-rich protein 2/3 (Pfhrp2/3) is threatening the diagnosis and management of malaria. Although regular monitoring is necessary to gauge the level of efficacy of the tool, studies in Cameroon remain limited. This study assessed Plasmodium spp. prevalence and Pfhrp2/3 gene deletions across ecological and transmission zones in Cameroon. METHODS: This is a cross-sectional, multi-site, community- and hospital- based study, in 21 health facilities and 14 communities covering all five ecological settings in low seasonal (LS) and intense perennial (IPT) malaria transmission zones between 2019 and 2021. Participants were screened for malaria parasite using Pfhrp2 RDT and light microscopic examination of thick peripheral blood smears. DNA was extracted from dried blood spot using chelex®-100 and P. falciparum confirmed using varATS real-time quantitative Polymerase Chain Reaction (qPCR), P. malariae and P. ovale by real-time qPCR of Plasmepsin gene, and P. vivax using a commercial kit. Isolates with amplified Pfcsp and Pfama-1 genes were assayed for Pfhrp 2/3 gene deletions by conventional PCR. RESULTS: A total of 3,373 participants enrolled, 1,786 Plasmodium spp. infected, with 77.4% P. falciparum. Discordant RDT and qPCR results (False negatives) were reported in 191 (15.7%) P. falciparum mono-infected samples from LS (29%, 42) and IPT (13.9%, 149). The Pfhrp2+/Pfhrp3 + genotype was most frequent, similar between LS (5.5%, 8/145) and IPT (6.0%, 65/1,076). Single Pfhrp2 and Pfhrp3 gene deletions occurred in LS (0.7%, 1/145 each) and IPT (3.6%, 39/1,076 vs. 2.9%, 31/1,076), respectively. Whilst a single sample harboured Pfhrp2-/Pfhrp3- genotype in LS, 2.4% (26/1,076) were double deleted at IPT. Pfhrp2+/Pfhrp3- (0.3%, 3/1,076) and Pfhrp2-/Pfhrp3+ (1.2%, 13/1,076) genotypes were only observed in IPT. Pfhrp2, Pfhrp3 deletions and Pfhrp2-/Pfhrp3- genotype accounted for 78.8% (26), 69.7% (23) and 63.6% (21) RDT false negatives, respectively. CONCLUSION: Plasmodium falciparum remains the most dominant and widely distributed Plasmodium species across transmission and ecological zones in Cameroon. Although the low prevalence of Pfhrp2/3 gene deletions supports the continued use of HRP2-based RDTs for routine malaria diagnosis, the high proportion of false-negatives due to gene deleted parasites necessitates continued surveillance to inform control and elimination efforts.

False-negative sentinel lymph node biopsy for melanoma: a single-surgeon experience.

BACKGROUND: The status of the regional lymph node basin is of prognostic importance in patients with melanoma, making the performance of sentinel lymph node biopsies (SLNBs) a key component of patient care management, particularly with the advent of immunotherapy for adjuvant treatment. The primary goal of our study was to assess the false-negative rate of SLNBs among patients with melanoma. METHODS: We conducted a retrospective review of patients with melanoma undergoing SLNB by a single surgeon between Jan. 1, 2005, and Dec. 31, 2020. We extracted and cross-referenced patient demographic and pathologic information. RESULTS: During the study period, 501 patients underwent an SLNB. Of these, 97 (19.4%) patients had pathologically positive sentinel lymph nodes and 404 (80.6%) patients had negative results. The latter were subject to further review; 84 (20.8%) patients subsequently developed recurrence, with 25 (6.2%) recurrences within the primary nodal basin. Isolated regional recurrence occurred in 11 (2.7%) patients and conjunction with a false-negative rate was 10.2%. Unadjusted recurrence rates were similar across each lymph node basin, including the axilla (2.7%), groin (3.6%), and neck (1.4%). CONCLUSION: The false-negative SLNB rate was 10.2% for isolated regional recurrences. These findings need to be considered in the era of using adjuvant systemic therapy for patients with melanoma.

A brief harvesting-freezing delay significantly alters the kidney metabolome and leads to false positive and negative results.

Abnormalities in distinct metabolic pathways have been associated with the pathogenesis and progression of many forms of kidney disease. Metabolomics analyses can be used to determine organ-specific metabolic fingerprints and, ideally, should represent the metabolic state of the organ at the exact moment the sample is harvested. However, conventional harvesting methods depend on posteuthanasia tissue harvest, which results in ischemia conditions and metabolome changes that could potentially introduce artifacts into the final studies. We recently optimized a modified clamp-freezing technique for rodent kidney harvesting and freezing, significantly reducing ischemia and freezing times and granting a closer snapshot of in vivo metabolism. In this study, we characterized and compared the metabolome of kidneys harvested using our modified approach versus traditional techniques to determine which metabolites are preferentially affected by a brief lapse of ischemia and freezing delay and which are more stable. We used Sprague-Dawley rats as a model of wild-type (WT) kidneys and PCK [polycystic kidney disease (PKD)] rats as a model of chronic kidney disease kidneys. Finally, we compared the metabolic profile of clamp-frozen and delayed WT and PKD kidneys to determine which metabolic changes are most likely observed in vivo in PKD and which could be subjected to false positive or negative results. Our data indicate that a short harvesting-freezing delay is sufficient to impart profound metabolic changes in WT and PKD kidneys, leading to false positive and negative differences when comparing these genotypes. In addition, we identified a group of metabolites that were more stable. Interestingly, while the delay had a similar effect between WT and PKD, there were notable differences. The data obtained indicate that the quick clamp-freezing technique for kidney metabolomics provides a more accurate interpretation of the in vivo metabolic changes associated with the disease state. NEW & NOTEWORTHY Our study shows that a brief harvesting-freezing delay associated with organ collection and freezing can significantly alter the kidney metabolic profile of both male and female wild-type and a genetic model of chronic kidney disease. Importantly, given that the effect of this delay differs among genotypes, it is not safe to assume that equally delaying harvesting-freezing in wild-type and polycystic kidney disease kidneys adequately controls this effect, ultimately leading to false positive and negative results among different renal diseases.

Clinical Evaluation of a New Chemiluminescence Assay for the Detection of Treponema Pallidum Antibodies.

BACKGROUND: A new chemiluminescence assay, the Anti-TP-Ⅱ assay, is going to be commercially available in clinical laboratories in China and other countries. This study examined the performance of the new assay for the detection of TP infection and compared it with that of the Anti-TP assay by using large amounts of clinical samples. METHODS: The precision, accuracy, anti-interference ability, and the clinical sensitivity and specificity of the Anti-TP-Ⅱ assay were evaluated. In addition, compared with those of the Anti-TP assay, the false positive and false negative rates of the Anti-TP-Ⅱ assay were evaluated for 2,436 clinical routine samples and 711 preselected Anti-TP assay reactive samples. Discrepancy of the samples was investigated with the recomLinec Treponema IgM/IgG kit or the Elecsys syphilis assay. RESULTS: The precision, accuracy, and anti-interference ability of the Anti-TP-Ⅱ assay met the national standard of China, and there was an overall agreement of 96.75% (Kappa = 0.91) between the two assays. The sensitivity and specificity of the Anti-TP-Ⅱ assay were 100% (95% CI: 94.13% to 100%) and 99.92% (95% CI: 99.70% to 99.99%), respectively. Compared with the Anti-TP assay, the Anti-TP-Ⅱ assay significantly reduced the number of borderline samples and the false positive rate. CONCLUSIONS: Considering its excellent performance, the Anti-TP-Ⅱ assay is a good screening test for high-throughput laboratories and can replace the previous generation of reagents, the Anti-TP assay, with a superior specificity.

Evaluation of COVID-19 rapid antigen test against polymerase chain reaction test in immunocompromised patients.

On the 11th of March 2020, the world faced a new global pandemic, COVID-19 which is a disease caused by the novel coronavirus, it had multiple devastating outcomes on multiple sectors along with significant rates of mortality. These challenges encouraged the development of multiple testing methods, as well as anti-viral medications such as Molnupiravir, as well as evaluating the efficacy of available medications against it, like; Azithromycin, Ritonavir and Hydroxychloroquine. Vaccination against COVID-19 forged into a significant challenge, few months ensuing the first case of SARS-CoV-2, which was diagnosed in December 2019, in Wuhan-China, thus, multiple vaccines were approved for use around the world to combat this pandemic. Our study includes a sample of 556 oncology patients at Augusta Victoria Hospital in Jerusalem, all patients were tested using Panbio rapid antigen test and Allplex PCR Assay. The main objective was to study the sensitivity and specificity of Rapid antigen test, which contributes to a faster isolation call and management of infected patients, thus decreasing the risk on spread to other patients and health care. Patients were categorized based on two factors: Ct range and age group and studying their possible effect on false-negative results. Patients with Ct value less than 20, had the highest detection rate which is consistent with other studies in the literature. The sensitivity and specificity of Panbio Rapid Antigen testing were of 69.9% and 100%, respectively. A correlation between age group and false negative results could not be made, but a correlation between Ct value and false negative result was noticed, Ct value was directly related to false negative results. P-value of 0.007 indicated that results were statistically significant where PCR test is considered more sensitive compared to rapid antigen test.

A Case of False Decrease of Plasma D-Dimer.

BACKGROUND: D-dimer, a specific product of cross-linked fibrin degradation, is of great clinical value in the early diagnosis of thrombotic diseases and in monitoring the efficacy of thrombolysis; therefore, the accuracy of D-dimer test results is crucial. METHODS: This article reports a case of a patient with disseminated intravascular coagulation (DIC) who experienced a false decrease in D-dimer due to the hook effect. RESULTS: The three D-dimer test results for DIC patients were 1.09 mg/L, 0.93 mg/L, and 1.43 mg/L. After sample dilution, the results were: first time (1:128) 842.24 mg/L, second time (1:128) 1,505.28 mg/L, third time (1:32) 415.68 mg/L. There was a significant difference in the three test results before and after dilution, because the D-dimer concentration was too high, exceeding the detection range and causing the hook effect, which falsely lowered the D-dimer value. CONCLUSIONS: When the D-dimer value of DIC patients does not match the clinical situation, the possibility of the hook effect should be considered, and the false decrease can be ruled out by the sample dilution method. In this way, accurate clinical results can be obtained to avoid delaying the diagnosis and treatment of DIC patients.

Kaiser score diagnosis of breast MRI lesions: Factors associated with false-negative and false-positive results.

PURPOSE: We sought factors associated with false-negative and false-positive results in the diagnosis of breast lesions using the Kaiser score (KS) on breast magnetic resonance imaging (MRI). METHODS: We retrospectively analyzed 1058 patients with 1058 breast lesions who underwent preoperative breast MRI with successful histopathologic results. Two radiologists assessed each lesion according to KS criteria, and clinicopathologic features and MRI findings were analyzed. Multivariate regression analysis was conducted to identify factors associated with false-negative and false-positive KS results. RESULTS: Of the 1058 lesions, 859 were malignant and 199 were benign. Particularly high misdiagnosis rates were observed for intraductal papilloma, inflammatory lesion, and mucinous carcinoma. For breast cancer, KS yielded 821 (95.6 %) true-positive and 38 (4.4 %) false-negative results. Multivariate analysis showed that smaller lesion size (≤1 cm) (OR, 3.698; 95 %CI, 1.430-9.567; p = 0.007), absence of ipsilateral breast hypervascularity (OR, 3.029; 95 %CI, 1.370-6.693; p = 0.006), and presence of hyperintensity on T2WI (OR, 2.405; 95 %CI, 1.121-5.162; p = 0.024) were significantly associated with false-negative breast cancer results. For benign lesions, KS yielded 141 (70.9 %) true-negative and 58 (29.1 %) false-positive results. Multivariate regression analysis revealed that non-mass enhancement lesions (OR, 4.660; 95 %CI, 2.018-10.762; p＜0.001), moderate/high background parenchymal enhancement (OR, 2.402; 95 %CI, 1.180-4.892; p = 0.016), and the presence of hyperintensity on T2WI (OR, 2.986; 95 %CI, 1.386-6.433; p = 0.005) were significantly associated with false-positive KS results. CONCLUSION: Several clinicopathologic and MRI features influence the accuracy of KS diagnosis. Understanding these factors may facilitate appropriate use of KS and guide alternative diagnostic approaches, ultimately improving diagnostic accuracy in the evaluation of breast lesions.

Combination of 2 Quantitative Immunoassays and Clinical Score Algorithm to Reduce False-Negative Results in Heparin-Induced Thrombocytopenia: Prevalence Study of Mauriziano Hospital in Turin, Italy.

BACKGROUND: Heparin-induced thrombocytopenia (HIT) is a serious adverse effect of heparin treatment caused by platelet-activating anti-platelet factor 4 (PF4)/heparin antibodies. Accurate diagnosis of HIT is essential but remains challenging. The aim of our study was to explore the performance of our optimized diagnostic laboratory algorithm, based on Chemiluminescence (CliA) and ELISA immunoassays, on suspected HIT patients. The study compared the prevalence of HIT diagnosis in A.O. Mauriziano with the literature. METHODS: 163 consecutive patients were investigated for suspected HIT with CliA HemosIL Acustar HIT-IgG, Werfen. HIT was ruled out in all patients with CliA <0.13 U/mL. All patients with CliA >0.13 U/mL were further investigated with Zymutest-HIA anti-PF4 IgG ELISA immunoassay. In these patients, HIT was ruled out on the combination of CliA between 0.13 and 1.0 U/mL followed by ELISA assay <0.300 OD. HIT was ruled in patients whose plasma tested positive or doubtful with CliA and positive with ELISA immunoassay and confirmed positive with a platelet aggregation test (PAT). Suspicion of HIT was revealed with clinical 4Ts score or recent suggestive anamnestic history. RESULTS: Our diagnostic algorithm ruled out HIT diagnosis in 144/163 patients (88%) and predicted a positive PAT in 5/19 (26%) of CliA positive (4/5) or ELISA positive and CliA doubtful (1/5) patients. CONCLUSIONS: Our prevalence was 3.1%, comparable with the literature. The approach combining 2 quantitative immunoassays' (CliA and ELISA) results and 4Ts score probability was able to rule out the diagnosis within 1 h in 66% of patients with suspected HIT and within 24 h in 88% of patients. In the remaining 12% of cases, management decisions have to be based on individualized judgment while awaiting functional confirming results (48-72 h).