Non- fumigatus Aspergillus infection associated with a negative Aspergillus precipitin test in patients with chronic pulmonary aspergillosis

Aspergillus antibody testing is key for the clinical diagnosis of chronic pulmonary aspergillosis (CPA) with high sensitivity. However, false-negative results in patients with CPA might be obtained, depending on the Aspergillus species. The aim of this study was to investigate which factors are associated with false-negative results in Aspergillus precipitin tests and whether the sensitivity of precipitin tests in CPA is influenced by Aspergillus fumigatus and non- fumigatus Aspergillus species. Between February 2012 and December 2020, 116 consecutive antifungal treatment-naïve patients with CPA were identified and included in this retrospective chart review. Aspergillus species isolated from the respiratory tract of patients were identified by DNA sequencing. Characteristics of patients with positive and negative results for Aspergillus precipitin tests were compared. The sensitivity of the Aspergillus precipitin tests was compared between patients with A. fumigatus -associated CPA and non- fumigatus Aspergillus -associated CPA. A non- fumigatus Aspergillus species was the only factor significantly associated with negative Aspergillus precipitin test results in patients with CPA in the multivariate analysis (hazard ratio: 8.3, 95% confidence interval: 3.2–22.1, p < 0.0001). The positivity of the Aspergillus precipitin test in patients with non- fumigatus Aspergillus -associated CPA was lower than that in patients with A. fumigatus -associated CPA (84.8% vs. 37.9%; p < 0.0001). These results revealed that the presence of non- fumigatus Aspergillus -associated CPA should be considered with a negative Aspergillus precipitin test; this finding may prevent diagnostic delay or misdiagnosis for CPA.

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Visualization of Lesions of Metaphyses and Epiphyses of Bones in Newborns and Young Children

Radiology - Practice ◽

10.52560/2713-0118-2021-5-82-90 ◽

2021 ◽

pp. 82-90

Author(s):

N. A. Sholokhova

Keyword(s):

Young Children ◽

False Negative ◽

Age Groups ◽

High Sensitivity ◽

Negative Results ◽

False Negative Results ◽

Inflammatory Processes ◽

Group 5 ◽

Magnetic Resonance Imaging Mri ◽

Diagnostic Capabilities

The aim of this study was to determine the diagnostic capabilities of various methods of radiological diagnostics for lesions of the metaphyses and epiphyses of bones in newborns and young children.The study involved 108 children in the age group 5 days – 12 months with pathological changes in the pineal gland and bone metaphysis. The possibilities and advantages of standard radiography (СR), ultrasound examination (US) and magnetic resonance imaging (MRI) in the early and differential diagnosis of the osteomyelitis process and epiphyseolysis have been determined. High sensitivity (98 %), specificity (99 %) and accuracy (98 %) for ultrasound and sensitivity (94 %), specificity (89 %) and accuracy (95 %) of MRI in diagnosing osteomyelitis in patients of this age groups. At the same time, the possibilities of standard radiography at the stages of early diagnosis of inflammatory processes in the distal parts of the bones were limited due to a number of factors. The use of diagnostic algorithms greatly facilitates the work of a radiologist and reduces the number of false negative results during the initial treatment of patients.

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CLINICAL APPLICATION OF COVID-19 REPORTING AND DATA SYSTEM IN COMPUTED TOMOGRAPHY OF BILATERAL PNEUMONIA DIAGNOSTIC

10.35988/sm-hs.2021.118 ◽

2021 ◽

Vol 31 (4) ◽

pp. 40-45

Author(s):

Ugnė Kulnickaitė ◽

Laura Dobrovaitė ◽

Kamilė Grigaitė ◽

Edvardas Jukna

Keyword(s):

Computed Tomography ◽

False Negative ◽

High Sensitivity ◽

Chest Ct ◽

Data System ◽

Negative Results ◽

Radiological Society ◽

Evaluation Scheme ◽

False Negative Results ◽

Standardized Reporting

Background: the 2019 coronavirus disease pandemic (COVID-19) has spread at an astonishing speed across the world, causing major morbidity and mortality. Computed tomography (CT) examination plays an important role in crisis areas in the diagnosis of COVID-19. COVID-19 Reporting and Data System (CO-RADS) has a five-point scale of suspicion for COVID-19 pneumonia in chest CT picture which standardizes the evaluation scheme and simplifies reporting. Aim: to summarise and present the role of COVID-19 Reporting and Data System in computed tomography of bilateral pneumonia diagnostic. Materials and methods: recently published studies were reviewed to evaluate COVID-19 Reporting and Data System scale as effective tool to detect COVID-19 pneumonia on chest CT scans. Databases from the subscription list of Lithuanian University of Health Sciences were selected: Medline (PubMed), SpringerLink and ScienceDirect. Results: chest CT features, as bilateral involvement, subpleural or peripherally distributed GGO, consolidation, reticulation, crazy paving pattern, air bronchogram signs, intralobular septal thickening, pulmonary vascular enlargement, are considered to be characteristic manifestations of COVID-19 infection. Studies show that Dutch Radiological Society presented CO-RADS scale sensitivity and specificity may vary from 61-88% and 66,4-98%, respectively. Conclusion: chest CT scan has a high sensitivity for COVID-19 diagnosis and could reduce false negative results obtained from RT-PCR tests. Furthermore, a standardized reporting system could increase clarification, minimize reporting variability and help radiologists recognize the results they observe, especially, for less experienced specialists.

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Pearls and Pitfalls of Interpretation in CT Colonography

Canadian Association of Radiologists Journal ◽

10.1177/0846537119892881 ◽

2020 ◽

Vol 71 (2) ◽

pp. 140-148

Author(s):

Michael Schonberger ◽

Philippe Lefere ◽

Abraham H. Dachman

Keyword(s):

Computed Tomography ◽

Sensitivity And Specificity ◽

False Positive ◽

Ct Colonography ◽

False Negative ◽

High Sensitivity ◽

Negative Results ◽

False Negative Results ◽

The Common

The accuracy of computed tomography (CT) colonography (CTC) requires that the radiologist be well trained in the recognition of pitfalls of interpretation. In order to achieve a high sensitivity and specificity, the interpreting radiologist must be well versed in the causes of both false-positive and false-negative results. In this article, we review the common and uncommon pitfalls of interpretation in CTC.

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Prozone-like phenomenon in travellers with fatal malaria: report of two cases

The Journal of Infection in Developing Countries ◽

10.3855/jidc.5454 ◽

2015 ◽

Vol 9 (03) ◽

pp. 321-324 ◽

Cited By ~ 6

Author(s):

Lurdes Santos ◽

Nuno Rocha Pereira ◽

Paulo Andrade ◽

Paulo Figueiredo Dias ◽

Carlos Lima Alves ◽

...

Keyword(s):

Diagnostic Tests ◽

False Negative ◽

Specific Antigen ◽

Malaria Diagnosis ◽

High Sensitivity ◽

Rapid Diagnostic Tests ◽

Microscopy Observation ◽

Negative Results ◽

False Negative Results ◽

Potential Benefits

Malaria diagnosis remains a concern in non-endemic countries, with rapid diagnosis being crucial to improve patients’ outcome. Rapid diagnostic tests have high sensitivity but they also have flaws and false-negative results that might jeopardize malaria diagnosis. Some false-negative results might relate to a prozone-like effect. The authors describe two patients with false-negative rapid diagnostic tests in which a prozone-like effect might have been involved. The authors highlight that these tests should not be used without accompanying light microscopy observation of blood films and discuss potential benefits of using rapid diagnostic tests with more than one specific antigen for Plasmodium falciparum.

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COVID-19 Testing – Impact of Prevalence, Sensitivity, and Specificity on Patient Risk and Cost

10.20944/preprints202006.0279.v2 ◽

2020 ◽

Author(s):

Zoe C. Brooks ◽

Saswati Das

Keyword(s):

False Positive ◽

False Negative ◽

Test Methods ◽

Antibody Testing ◽

Patient Risk ◽

Advantages And Disadvantages ◽

Negative Results ◽

False Negative Results ◽

Antigen Tests ◽

Positive Agreement

Since the beginning of the year 2020, the global healthcare system has been challenged by the threat of the SARS-COV 2 virus. Molecular, antigen, and antibody testing are the mainstay to identify infected patients and fight the virus. Molecular and antigen tests that detect the presence of the virus are relevant in the acute phase only. Serological assays detect antibodies to the Sars-CoV-2 virus in the recovering and recovered phase. Each testing methodology has its advantages and disadvantages. To evaluate the test methods, sensitivity (percent positive agreement - PPA) and specificity (percent negative agreement – PNA) are the most common metrics utilized, followed by the positive and negative predictive value (PPV and NPV), the probability that a positive or negative test result represents a true positive or negative patient. In this paper, we illustrate how patient risk and clinical costs are driven by false-positive and false-negative results. We demonstrate the value of reporting PFP (probability of false positive results), PFN (probability of false negative results), and costs to patients and healthcare. These risk metrics can be calculated from the risk drivers of PPA and PNA combined with estimates of prevalence, cost, and Reff number (people infected by one positive SARS COV-2).

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Cell-free DNA screening for aneuploidies in 7113 pregnancies: single Italian centre study

Genetics Research ◽

10.1017/s001667232000004x ◽

2020 ◽

Vol 102 ◽

Cited By ~ 1

Author(s):

Alvaro Mesoraca ◽

Katia Margiotti ◽

Claudio Dello Russo ◽

Anthony Cesta ◽

Antonella Cima ◽

...

Keyword(s):

Sex Chromosome ◽

Clinical Performance ◽

False Negative ◽

Prenatal Testing ◽

High Sensitivity ◽

Trisomy 13 ◽

Sequencing Platform ◽

Non Invasive ◽

Negative Results ◽

False Negative Results

Abstract Introduction Non-invasive prenatal testing (NIPT) using cell-free foetal DNA has been widely accepted in recent years for detecting common foetal chromosome aneuploidies, such as trisomies 13, 18 and 21, and sex chromosome aneuploidies. In this study, the practical clinical performance of our foetal DNA testing was evaluated for analysing all chromosome aberrations among 7113 pregnancies in Italy. Methods This study was a retrospective analysis of collected NIPT data from the Ion S5 next-generation sequencing platform obtained from Altamedica Medical Centre in Rome, Italy. Results In this study, NIPT showed 100% sensitivity and 99.9% specificity for trisomies 13, 18 and 21. Out of the 7113 samples analysed, 74 cases (1%) were positive by NIPT testing; foetal karyotyping and follow-up results validated 2 trisomy 13 cases, 5 trisomy 18 cases, 58 trisomy 21 cases and 10 sex chromosome aneuploidy cases. There were no false-negative results. Conclusion In our hands, NIPT had high sensitivity and specificity for common chromosomal aneuploidies such as trisomies 13, 18 and 21.

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Unexplained False Negative Results in Noninvasive Prenatal Testing: Two Cases Involving Trisomies 13 and 18

Case Reports in Genetics ◽

10.1155/2015/926545 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 4

Author(s):

R. Hochstenbach ◽

G. C. M. L. Page-Christiaens ◽

A. C. C. van Oppen ◽

K. D. Lichtenbelt ◽

J. J. T. van Harssel ◽

...

Keyword(s):

False Negative ◽

Prenatal Testing ◽

High Sensitivity ◽

Trisomy 13 ◽

Maternal Weight ◽

Noninvasive Prenatal Testing ◽

Root Cause ◽

Negative Results ◽

False Negative Results ◽

Negative Case

Noninvasive prenatal testing (NIPT) validation studies show high sensitivity and specificity for detection of trisomies 13, 18, and 21. False negative cases have rarely been reported. We describe a false negative case of trisomy 13 and another of trisomy 18 in which NIPT was commercially marketed directly to the clinician. Both cases came to our attention because a fetal anatomy scan at 20 weeks of gestation revealed multiple anomalies. Karyotyping of cultured amniocytes showed nonmosaic trisomies 13 and 18, respectively. Cytogenetic investigation of cytotrophoblast cells from multiple placental biopsies showed a low proportion of nontrisomic cells in each case, but this was considered too small for explaining the false negative NIPT result. The discordant results also could not be explained by early gestational age, elevated maternal weight, a vanishing twin, or suboptimal storage or transport of samples. The root cause of the discrepancies could, therefore, not be identified. The couples involved experienced difficulties in accepting the unexpected and late-adverse outcome of their pregnancy. We recommend that all parties involved in caring for couples who choose NIPT should collaborate to clarify false negative results in order to unravel possible biological causes and to improve the process of patient care from initial counseling to communication of the result.

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Assessment of the IgA Immunoassay Diagnostic Potential of the Mycobacterium tuberculosis MT10.3-MPT64 Fusion Protein in Tuberculous Pleural Fluid

Clinical and Vaccine Immunology ◽

10.1128/cvi.00372-10 ◽

2010 ◽

Vol 17 (12) ◽

pp. 1963-1969 ◽

Cited By ~ 10

Author(s):

Leonardo Silva Araujo ◽

Renata Maciel Moraes ◽

Anete Trajman ◽

Maria Helena Féres Saad

Keyword(s):

Pleural Fluid ◽

Histopathological Examination ◽

False Negative ◽

High Sensitivity ◽

Enzyme Linked Immunosorbent Assay ◽

Negative Results ◽

Diagnostic Potential ◽

False Negative Results ◽

Sds Page ◽

Increased Sensitivity

ABSTRACT Pleural tuberculosis (PL-TB) remains difficult to diagnose. An enzyme-linked immunosorbent assay (ELISA) was developed based on a construction containing the fusion of the Rv3019c (MT10.3) and Rv1980c (MPT64) gene sequences, and its performance was evaluated in an area where TB is endemic. A total of 92 pleural fluid (PF) samples at serial dilutions of 1:50 to 1:800 were included in the ELISA IgA MT10.3-MPT64 evaluation: 70 from TB patients and 22 from patients with other pleurisies. Confirmation of the expression and subsequent purification of the protein was made by SDS-PAGE and Western blot assays, resulting in a 36-kDa protein. ELISA IgA MT10.3-MPT64 showed sensitivities of 61.4%, 58.6%, 62.9%, 67.1%, and 70% at each PF dilution, respectively. The cumulative results of all dilutions increased sensitivity to 81.4% without jeopardizing specificity. Similar results were also obtained at the combined dilutions of 1:50, 1:200, and 1:800 or 1:50 plus 1:800 dilutions (80%). The overall sensitivity of the reference test, i.e., histopathological examination, was 74%. But, via the ELISA IgA MT10.3-MPT64 test, sensitivity was high for specimens with a negative culture (23/27; 85.2%) or nonspecific histopathology (17/18; 94.4%). Our findings demonstrated the promising use of this test as an adjunct in PL-TB diagnoses, particularly in cases with lower bacterial loads and false-negative results in the reference tests, since the new test includes such important features as quick and easy application, high sensitivity and, perhaps most importantly, affordability, which is so crucial for its widespread use in developing countries.

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Role and limits of testicular phleboscintigraphy in the diagnostic evaluation of varicocele

Urologia Journal ◽

10.1177/039156039406100202 ◽

1994 ◽

Vol 61 (2) ◽

pp. 98-102

Author(s):

A. Raimoldi ◽

G.L. Berti ◽

V. Giola ◽

G.L. Leidi ◽

A. Maccaroni ◽

...

Keyword(s):

Doppler Ultrasonography ◽

Low Cost ◽

False Negative ◽

High Sensitivity ◽

Diagnostic Evaluation ◽

Ultrasound Technique ◽

Negative Results ◽

False Negative Results ◽

First Choice ◽

Choice Method

The Authors wanted to check the reliability of testicular phleboscintigraphy in the diagnostic evaluation of varicocele, comparing it to Doppler ultrasonography. To this end, 98 patients affected by clinically evident left idiopathic varicocele were tested. The two methods gave equivalent results in all patients affected by 2nd and 3rd clinical degree varicocele, while testicular phleboscintigraphy gave false negative results in 7 patients with 1st degree varicocele, due to renospermatic retrograde flow. Therefore, in the Authors' opinion, the Doppler ultrasound technique can be considered as a first choice method in the study of varicocele, thanks to its high sensitivity associated with low cost, whereas testicular phleboscintigraphy can be used either when Doppler ultrasonography evaluation is not reliable or as a second examination to confirm the Doppler results, especially in patients with 2nd and 3rd clinical degree varicocele.

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Development of a Direct and Rapid Detection Method for Viable but Non-culturable State of Pediococcus acidilactici

Frontiers in Microbiology ◽

10.3389/fmicb.2021.687691 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yu Guan ◽

Kan Wang ◽

Yang Zeng ◽

Yanrui Ye ◽

Ling Chen ◽

...

Keyword(s):

Detection Method ◽

Ph Value ◽

False Negative ◽

High Sensitivity ◽

Pediococcus Acidilactici ◽

Propidium Monoazide ◽

Vbnc State ◽

Negative Results ◽

False Negative Results ◽

Standard Culture

Pediococcus acidilactici may significantly reduce the pH-value, and thus has different influence, including serving as a probiotic in human microbiota but a spoilage in human food as it could change the flavor. Pediococcus acidilactici is also capable of entering into the viable but non-culturable (VBNC) state causing false negative results of standard culture-based detection method. Thus, development of detection method for VBNC state P. acidilactici is of great significance. In this study, propidium monoazide (PMA) combined with cross priming amplification (CPA) was developed to detect the VBNC cells of P. acidilactici and applied on the detection in different systems. With detection limit of 104 cells/ml, high sensitivity, and 100% specificity, PMA-CPA can successfully detect VBNC cells of P. acidilactici and be applied in with high robustness.

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