Diagnostic accuracy of seven radiographic views, alone and in combination, for diagnosis of pectoral girdle fractures in wild passerines after window collisions

2022 ◽  
pp. 1-6
Author(s):  
Crystal L. Matt ◽  
Nicola Di Girolamo ◽  
Ruth M. Hallman ◽  
Keith L. Bailey ◽  
Timothy J. O’Connell ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
False Positive ◽  
Clinical Relevance ◽  
False Negative ◽  
Pectoral Girdle ◽  
Blinded Observer ◽  
Positive Results ◽  
Limited Accuracy

Abstract OBJECTIVE To determine the prevalence of pectoral girdle fractures in wild passerines found dead following presumed window collision and evaluate the diagnostic accuracy of various radiographic views for diagnosis of pectoral girdle fractures. SAMPLE Cadavers of 103 wild passerines that presumptively died as a result of window collisions. PROCEDURES Seven radiographic projections (ventrodorsal, dorsoventral, lateral, and 4 oblique views) were obtained for each cadaver. A necropsy was then performed, and each bone of the pectoral girdle (coracoid, clavicle, and scapula) was evaluated for fractures. Radiographs were evaluated in a randomized order by a blinded observer, and results were compared with results of necropsy. RESULTS Fifty-six of the 103 (54%) cadavers had ≥ 1 pectoral girdle fracture. Overall accuracy of using individual radiographic projections to diagnose pectoral girdle fractures ranged from 63.1% to 72.8%, sensitivity ranged from 21.3% to 51.1%, and specificity ranged from 85.7% to 100.0%. The sensitivity of using various combinations of radiographic projections to diagnose pectoral girdle fractures ranged from 51.1% to 66.0%; specificity ranged from 76.8% to 96.4%. CLINICAL RELEVANCE Radiography alone appeared to have limited accuracy for diagnosing fractures of the bones of the pectoral girdle in wild passerines after collision with a window. Both individual radiographic projections and combinations of projections resulted in numerous false negative but few false positive results.

scholarly journals Fast Detection And Quantification of Plasmodium Species Infected Erythrocytes In A Non-Endemic Region By Using The Sysmex XN-31 Analyzer

2021 ◽  
Author(s):  
T.A. Khartabil ◽  
Y.B. de Rijke ◽  
R. Koelewijn ◽  
J.J. van Hellemond ◽  
H. Russcher
Keyword(s):  
Diagnostic Accuracy ◽  
Red Blood Cells ◽  
False Positive ◽  
Blood Cells ◽  
False Negative ◽  
Screening Method ◽  
Plasmodium Species ◽  
Endemic Region ◽  
Positive Results ◽  
Detection And Quantification

Abstract BACKGOUND: Due to increased travel from endemic countries, malaria occurs more frequently in non-endemic regions. It is a challenge for diagnostic laboratories in non-endemic countries to provide reliable results, as experience of staff is often limited to only a few cases per year. In this study, we evaluated the diagnostic accuracy of the fully automated Sysmex XN-31 malaria analyzer in a routine diagnostic setting in a non-endemic region. METHODS: Samples from 112 patients suspected for malaria were examined by the Sysmex XN-31 analyzer to determine the absolute count of malaria-infected red blood cells count (MI-RBC/µl). Microscopic examination of both Quantitative Blood Coat capillary tubes and thick and thin blood films were used as reference methods. Limits of blank (LoB), detection (LoD) and quantification (LoQ) were investigated using an in vitro Plasmodium falciparum culture . Nine hundred twenty samples of patients with RBC abnormalities were included to determine which RBC abnormalities trigger indeterminate or false positive results. RESULTS: No false positive nor false negative results were obtained for the examined patient samples suspected for malaria. For 3% of samples an indeterminate result by the XN-31 was obtained. The Passing-Bablok regression line for diagnostic accuracy of the parasitemia was y = 39.75 + 0.7892x showing a positive bias of about 21% when comparing the MI-RBC results to microscopy. The LoB, LoD and LoQ were calculated to be 4.7, 5.9, and 19.0 infected RBC/mL, respectively. From the 920 abnormal RBC samples collected, 4.6% resulted in a false positive MI-RBC result and almost half of the samples produced indeterminate results. These results were related to increases in nucleated red blood cells, reticulocytes and other abnormal RBC morphologies such as sickle cells. CONCLUSIONS: Based on the results we conclude that the XN-31 is a fast and reliable screening method in the detection and quantification of Plasmodium species in patients However, if an abnormal red blood cell morphology is present, the results of the XN-31 should be interpreted with caution as false positive results can be caused by interfering abnormal erythrocytes.

Critical Evaluation of Impedance Phlebography for the Diagnosis of Deep Vein Thrombosis

1974 ◽  
Vol 31 (02) ◽  
pp. 273-278
Author(s):  
Kenneth K Wu ◽  
John C Hoak ◽  
Robert W Barnes ◽  
Stuart L Frankel
Keyword(s):  
Deep Vein Thrombosis ◽  
False Positive ◽  
False Negative ◽  
Critical Evaluation ◽  
Original Method ◽  
Vein Thrombosis ◽  
Negative Results ◽  
False Negative Results ◽  
Deep Vein ◽  
Positive Results

SummaryIn order to evaluate its daily variability and reliability, impedance phlebography was performed daily or on alternate days on 61 patients with deep vein thrombosis, of whom 47 also had 125I-fibrinogen uptake tests and 22 had radiographic venography. The results showed that impedance phlebography was highly variable and poorly reliable. False positive results were noted in 8 limbs (18%) and false negative results in 3 limbs (7%). Despite its being simple, rapid and noninvasive, its clinical usefulness is doubtful when performed according to the original method.

Three Years of Experience With Random Urinary Homovanillic and Vanillylmandelic Acid Levels in the Diagnosis of Neuroblastoma

PEDIATRICS ◽  
1987 ◽  
Vol 79 (2) ◽  
pp. 203-205
Author(s):  
Mendel Tuchman ◽  
Margaret L. R. Ramnaraine ◽  
William G. Woods ◽  
William Krivit
Keyword(s):  
False Positive ◽  
Homovanillic Acid ◽  
False Negative ◽  
False Negative Rate ◽  
Urine Samples ◽  
Vanillylmandelic Acid ◽  
Test Results ◽  
Upper Limit ◽  
Positive Results ◽  
Rule Out

During the last 3 years, random urine samples from 408 patients were tested for elevated homovanillic acid (HVA) and vanillylmandelic acid (VMA) levels to rule out the diagnosis of neuroblastoma. Thirty-seven of these patients had elevated HVA and/or VMA levels, and neuroblastoma was subsequently diagnosed. In three additional patients with negative test results (normal HVA and VMA levels), tumors were subsequently diagnosed (false-negative rate of 7.5%). Ten percent of the patients with neuroblastoma had normal HVA and 27.5% had normal VMA levels at the time of diagnosis. Only one patient (2.5%) with neuroblastoma had elevated VMA levels in the presence of normal HVA levels. More than 60% of the patients with neuroblastoma had urinary HVA and/or VMA levels higher than twice the upper limit of normal. No false-positive results were encountered. Age and stage distributions of the patients are shown, and the significance of the results is discussed.

N.B.T. TEST—FALSE-NEGATIVE AND FALSE-POSITIVE RESULTS

The Lancet ◽  
1972 ◽  
Vol 299 (7764) ◽  
pp. 1341-1342 ◽  
Author(s):  
RonaldP. Ng ◽  
T.K. Chan ◽  
D. Todd
Keyword(s):  
False Positive ◽  
False Negative ◽  
Positive Results

Interpretation of Abnormal Dexamethasone Suppression Test is Enhanced With Use of Synchronous Free Cortisol Assessment

2021 ◽  
Author(s):  
Natalia Genere ◽  
Ravinder Jeet Kaur ◽  
Shobana Athimulam ◽  
Melinda A Thomas ◽  
Todd Nippoldt ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
False Positive ◽  
Medical Center ◽  
Dexamethasone Suppression Test ◽  
Total Cortisol ◽  
Normal Ranges ◽  
Free Cortisol ◽  
Suppression Test ◽  
Dexamethasone Suppression ◽  
Positive Results

Abstract Context Interpretation of dexamethasone suppression test (DST) may be influenced by dexamethasone absorption and metabolism and by the altered cortisol binding Objective We aimed to determine the normal ranges of free cortisol during DST in participants without adrenal disorders, and to identify the population of patients where post-DST free cortisol measurements add value to the diagnostic work up. Design and Setting Cross-sectional study conducted in a tertiary medical center Participants Adult volunteers without adrenal disorders (n=168; 47 women on oral contraceptive therapy (OCP), 66 women not on OCP, 55 men) and patients undergoing evaluation for hypercortisolism (n=196; 16 women on OCP) Measurements Post-DST dexamethasone and free cortisol (mass spectrometry) and total cortisol (immunoassay). Main Outcome Measures Reference range for post-DST free cortisol, diagnostic accuracy of post-DST total cortisol. Results Adequate dexamethasone concentrations (≥0.1 mcg/dL) were seen in 97.6% volunteers and 96.3% patients. Only 25.5% of women volunteers on OCP had abnormal post-DST total cortisol (>1.8 mcg/dL). In volunteers, the upper post-DST free cortisol range was 48 ng/dL in men and women not on OCP, and 79 ng/dL in women on OCP. When compared to post-DST free cortisol, diagnostic accuracy of post-DST total cortisol was 87.3% (95%CI 81.7-91.7); all false positive results occurred in patients with post-DST cortisol between 1.8 and 5 mcg/dL. OCP use was the only factor associated with false positive results (21.1% vs 4.9%, p=0.02). Conclusions Post-DST free cortisol measurements are valuable in patients with optimal dexamethasone concentrations and post-DST total cortisol between 1.8 and 5 mcg/dL.

Thyroid Screening for Early Discharged Infants

PEDIATRICS ◽  
1996 ◽  
Vol 98 (1) ◽  
pp. 41-44
Author(s):  
Judy G. Saslow ◽  
Ernest M. Post ◽  
Carol A. Southard
Keyword(s):  
New Jersey ◽  
Congenital Hypothyroidism ◽  
False Positive ◽  
False Negative ◽  
Negative Results ◽  
Thyroid Screening ◽  
False Negative Results ◽  
Positive Results

Objective. As neonatal discharge before 24 hours of life becomes commonplace, the rejection of congenital hypothyroidism (CH) screening specimens obtained too early has created the need for numerous additional tests. We sought to determine whether the specimens obtained before 24 hours could be used safely. Methods. During a 31-day period we measured thyrotropin in all thyroid-screening specimens that had been obtained before 24 hours. We also examined the early specimens from every infant diagnosed in New Jersey with CH during 1993 or 1994. Results. Among the 663 specimens, those obtained at or before 12 hours and those from infants with birth weights less than 2500 g had too many low thyroxine results to be useful. Among the 515 specimens obtained at more than 12 to 24 hours from newborns weighing 2500 g or more, 37 (7%) had low thyroxine levels and 12 (2.3%) had thyrotropin levels of 20 µIU/mL (mU/L) or higher. Four hundred seventy-one of the 515 infants had subsequent specimens obtained at more than 24 hours, and none of the results were abnormal. There was no child weighing more than or equal to 2500 g who was diagnosed with CH in 1993 and 1994 whose specimen obtained at 24 hours or less was normal. Conclusions. Accepting specimens obtained at more than 12 to 24 hours from infants weighing 2500 g or more would have resulted in more than the usual number of false-positive results but no false-negative results. This would have decreased the requests for additional specimens by more than 90%.

scholarly journals Factors associated with false negative and false positive results of prostate-specific antigen (PSA) and the impact on patient health

Medicine ◽  
2019 ◽  
Vol 98 (40) ◽  
pp. e17451 ◽  
Author(s):  
Mari Carmen Bernal-Soriano ◽  
Lucy A. Parker ◽  
Maite López-Garrigos ◽  
Ildefonso Hernández-Aguado ◽  
Juan P. Caballero-Romeu ◽  
...  
Keyword(s):  
Prostate Specific Antigen ◽  
False Positive ◽  
False Negative ◽  
Specific Antigen ◽  
Factors Associated ◽  
Patient Health ◽  
The Impact ◽  
Positive Results

Simple modifications of three routine in vitro tests of thyroid function.

1976 ◽  
Vol 22 (10) ◽  
pp. 1715-1718 ◽  
Author(s):  
R W Pain
Keyword(s):  
Diagnostic Accuracy ◽  
Thyroid Function ◽  
False Positive ◽  
Reference Range ◽  
False Negative ◽  
Work Load ◽  
In Vitro Tests ◽  
Free Thyroxine Index ◽  
Total Thyroxine

Abstract Semi-automation of equipment and simple modifications of technique reduced the work load without loss of diagnostic accuracy for three commonly used in vitro tests of thyroid function (total thyroxine, thyrobinding index, and free thyroxine index). Major innovations were the use of serum standards for all tests and having each duplicate for tests performed by a different technician. Attention is drawn to the false-positive and false-negative errors that occur when the 95% euthyroid limits is the sole reference range used.

Sign in / Sign up

Export Citation Format

Share Document