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Diagnostic Performance (diagnostic + performance)
Selected AbstractsDiagnostic Performance of Various QTc Interval Formulas in a Large Family with Long QT Syndrome Type 3: Bazett's Formula Not So Bad After All ,ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 4 2003Jan Brouwer M.D., M.Sc., Ph.D. Background: Recently, we identified a novel mutation of SCN5A (1795insD) in a large family with LQTS3. The aim of this study was to assess whether the various proposed corrections of the QT interval to heart rate help to improve the identification of carriers of the mutant gene. Methods: The study group consisted of 101 adult family members: 57 carriers and 44 noncarriers (mean age 44.6 ± 14.6 and 40.3 ± 12.8 years, respectively). In all individuals a 12-lead ECG, exercise ECG, and 24-hour Holter ECG were obtained. Results: Correction for heart rate significantly improved the diagnostic performance of the QT interval. Diagnostic performance of the Bazett formula was similar to that of the newer formulas (Fridericia, Hodges, Framingham, and a logarithmic formula). At a cut-off value of 440 ms, the Bazett corrected QT interval was associated with a sensitivity and specificity of 90% and 91%, respectively. Using the 24-hour Holter ECG, a prolonged QTc at heart rates less than 60 beats/min was almost pathognomonic for genetic mutation (sensitivity and specificity both 99%), whereas the QTc calculated at the lowest heart rate using Bazett's formula provided full discrimination. Conclusion: In the present family, the resting ECG gave a good indication about the presence or absence of genetic mutation but a 24-hour Holter recording was mandatory to ascertain the diagnosis. In the diagnosis of this form of LQTS3, Bazett's formula was at least as good as other proposed corrections of the QT interval to heart rate. [source] Diagnostic performance of clinical motor and non-motor tests of Parkinson disease: a matched case,control studyEUROPEAN JOURNAL OF NEUROLOGY, Issue 7 2008N. I. Bohnen Background and purpose:, The diagnosis of Parkinson disease (PD) is made typically on the basis of motor abnormalities. PD is now recognized to have both motor and non-motor manifestations, indicating a need for the development of reliable non-motor diagnostic tests for PD. The aim of the present study was to compare the accuracy of various clinical motor and non-motor tests for the diagnosis of PD. Methods:, Forty-five PD patients (Hoehn and Yahr stages 1,3; mean age 59.5 ± 10.0 years) and 45 healthy controls matched for gender and age completed a clinimetric motor test battery to assess limb bradykinesia, tremor and balance. Non-motor tests consisted of depression, anxiety and smell identification ratings. Area under the receiver operator characteristic curve (AUC) analysis was used. Results:, We found that smell identification was the most accurate predictor of the presence of PD within the overall group of patients and matched control subjects (AUC = 0.886) and also in the subgroups of mild severity (Hoehn and Yahr stages 1,1.5; AUC = 0.923), young-onset (AUC = 0.888) and female PD patients (AUC = 0.797). The second best diagnostic test was the grooved pegboard test for the clinically most affected body side. Conclusions:, We conclude that olfactory function is the most accurate diagnostic predictor within a heterogeneous sample of patients with PD. [source] The Use of Impedance Cardiography in Predicting Mortality in Emergency Department Patients With Severe Sepsis and Septic ShockACADEMIC EMERGENCY MEDICINE, Issue 4 2010Anthony M. Napoli MD Abstract Objectives:, Pulmonary artery catheterization poses significant risks and requires specialized training. Technological advances allow for more readily available, noninvasive clinical measurements of hemodynamics. Few studies exist that assess the efficacy of noninvasive hemodynamic monitoring in sepsis patients. The authors hypothesized that cardiac index, as measured noninvasively by impedance cardiography (ICG) in emergency department (ED) patients undergoing early goal-directed therapy (EGDT) for sepsis, would be associated with in-hospital mortality. Methods:, This was a prospective observational cohort study of patients age over 18 years meeting criteria for EGDT (lactate > 4 or systolic blood pressure < 90 after 2 L of normal saline). Initial measurements of cardiac index were obtained by ICG. Patients were followed throughout their hospital course until discharge or in-hospital death. Cardiac index measures in survivors and nonsurvivors are presented as means and 95% confidence intervals (CI). Diagnostic performance of ICG in predicting mortality was tested by receiver operating characteristic (ROC) curve and areas under the ROC curves (AUC) were compared using Wilcoxon test. Results:, Fifty-six patients were enrolled; one was excluded due to an inability to complete data acquisition. The mean cardiac index in nonsurvivors (2.3 L/min·m2, 95% CI = 1.6 to 3.0) was less than that for survivors (3.2, 95% CI = 2.9 to 3.5) with mean difference of 0.9 (95% CI = 0.12 to 1.71). The AUC for ICG in predicting mortality was 0.71 (95% CI = 0.58 to 0.88; p = 0.004). A cardiac index of < 2 L/min·m2 had a sensitivity of 43% (95% CI = 18% to 71%), specificity of 93% (95% CI = 80% to 95%), positive likelihood ratio of 5.9, and negative likelihood ratio of 0.6 for predicting in-hospital mortality. Conclusions:, Early, noninvasive measurement of the cardiac index in critically ill severe sepsis and septic shock patients can be performed in the ED for those who meet criteria for EGDT. There appears to be an association between an initial lower cardiac index as measured noninvasively and in-hospital mortality. ACADEMIC EMERGENCY MEDICINE 2010; 17:452,455 © 2010 by the Society for Academic Emergency Medicine [source] Diagnostic performance of the variant lymphocyte flag of the Abbott Cell-Dyn 4000 haematology analyserINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 1 2004J. J. M. L. Hoffmann Summary Background: In addition to differential cell counts, modern haematology analysers generate suspect flags if abnormal cells are detected. Reports on validation of suspect flags are scarce. We have routine experience with the Abbott Cell-Dyn 4000 analyser for over 5 years and have previously demonstrated the utility of the blast flag. Here we report a similar study on the performance of the analyser's Variant Lymphocyte (VL) flag. Aim of the study: Evaluation of the diagnostic performance of the Cell-Dyn 4000 VL flag, as compared with lymphocyte morphology in blood smears. In addition, we investigated the usefulness of the numerical VL flag confidence index as provided by the analyser. Materials and methods: All samples generating a VL flag were reviewed over a 5-month period. We also reviewed smears from patients with known lymphoid disorders, even if the analyser did not flag the sample. Two experienced investigators assessed lymphocyte morphology independently. Results: In total, 187 samples were included in the study, of which 183 had a VL flag and four had not. Of the 183 flagged samples, 83 appeared to have abnormal lymphocyte morphology and 100, normal lymphocyte morphology. The sensitivity of the VL flag for detecting abnormal lymphocytes was 0.95 and the positive predictive value was 0.44. Using ROC analysis of the VL flag confidence index, the area under the ROC curve was 0.58 (95% confidence interval 0.50,0.65). Conclusions: The Cell-Dyn VL flag has reasonable sensitivity but a high false-positive rate. In addition, its performance is insufficient for detecting clinically relevant abnormal lymphocytes. As the VL flag appeared to rely mainly on numerical criteria, it has no added value over numerical criteria defined by the laboratory. [source] Diagnostic performance of three-dimensional ultrasound extended imaging at scrotal mass lesionsINTERNATIONAL JOURNAL OF UROLOGY, Issue 11 2007Salah Elwagdy Objectives: High resolution two-dimensional ultrasound (2D US) difficulty in evaluation of some scrotal mass lesions is not frequent. The aim of the present study was to prospectively evaluate the diagnostic performance of three-dimensional ultrasound extended imaging (3D XI) in characterization of those lesions. Methods: The study protocol had the approval of the University's review board all participants' informed consents were obtained. The study included 28 selected patients (12 testicular and 16 para-testicular mass lesions) examined by 2D US and 3D XI applications including computed multi-slice view (MSV) and multi-resolution enhanced images (XI MR). Results were correlated with histopathological findings. Results: Two-dimensional ultrasound did not adequately characterize 28 patients out of 329 (8.5%). 3D XI interrogation was an easy procedure and distinctive of the pathological findings in 27 patients out of 28 (96.4%). The performance of XI MR with respect to characterization provided additional diagnostic information over MSV. Conclusions: The performance of 3D XI with respect to testicular mass characterization proved better than static 2D US. Subsequently, the results of this study suggest that the routine use of 2D US in diagnosis of scrotal mass lesions should preferably be upgraded to 3D XI methods. [source] Evaluation of local recurrence after treatment for hepatocellular carcinoma by contrast-enhanced ultrasonography using Sonazoid: Comparison with dynamic computed tomographyJOURNAL OF CLINICAL ULTRASOUND, Issue 4 2010Kazue Shiozawa MD Abstract Purpose. To evaluate the effectiveness of contrast-enhanced ultrasonography (CEUS) using Sonazoid for the diagnosis of the local recurrence after treatment for hepatocellular carcinoma (HCC) by comparing it with dynamic CT. Methods. Seventy-one patients with 87 HCC lesions (mean ± SD; 19.5 ± 9.6 mm) underwent CEUS using Sonazoid and dynamic CT after radiofrequency ablation (n = 55), transcatheter arterial chemoembolization (n = 22), or radiofrequency ablation combined with transcatheter arterial chemoembolization (n = 10). Two hepatologists (observer 1; 10 years of experience, and 2; 20 years of experience) reviewed the CEUS and dynamic CT images independently and evaluated presence or absence of the local recurrence. Diagnostic performance for the local recurrence was assessed using receiver operating characteristic curve analysis. Results. The Az value for dynamic CT was significantly lower in observer 1 than 2 (p < 0.05). The sensitivity of CEUS was 79% in observer 1 and 83.9% in observer 2, and that of dynamic CT was 83.9% and 90.3%, respectively. The specificity of CEUS was 96%, and that of dynamic CT was 92%, in both observers. Conclusion. This study suggests that CEUS using Sonazoid is less affected by the observer's experience and is more accurate in the diagnosis of local recurrence after treatment for HCC than dynamic CT. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound, 2010 [source] Diagnostic Performance of Various QTc Interval Formulas in a Large Family with Long QT Syndrome Type 3: Bazett's Formula Not So Bad After All ,ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 4 2003Jan Brouwer M.D., M.Sc., Ph.D. Background: Recently, we identified a novel mutation of SCN5A (1795insD) in a large family with LQTS3. The aim of this study was to assess whether the various proposed corrections of the QT interval to heart rate help to improve the identification of carriers of the mutant gene. Methods: The study group consisted of 101 adult family members: 57 carriers and 44 noncarriers (mean age 44.6 ± 14.6 and 40.3 ± 12.8 years, respectively). In all individuals a 12-lead ECG, exercise ECG, and 24-hour Holter ECG were obtained. Results: Correction for heart rate significantly improved the diagnostic performance of the QT interval. Diagnostic performance of the Bazett formula was similar to that of the newer formulas (Fridericia, Hodges, Framingham, and a logarithmic formula). At a cut-off value of 440 ms, the Bazett corrected QT interval was associated with a sensitivity and specificity of 90% and 91%, respectively. Using the 24-hour Holter ECG, a prolonged QTc at heart rates less than 60 beats/min was almost pathognomonic for genetic mutation (sensitivity and specificity both 99%), whereas the QTc calculated at the lowest heart rate using Bazett's formula provided full discrimination. Conclusion: In the present family, the resting ECG gave a good indication about the presence or absence of genetic mutation but a 24-hour Holter recording was mandatory to ascertain the diagnosis. In the diagnosis of this form of LQTS3, Bazett's formula was at least as good as other proposed corrections of the QT interval to heart rate. [source] Diagnosing bipolar disorder in trauma exposed primary care patientsBIPOLAR DISORDERS, Issue 4 2007Ruth Elaine Graves Objectives:, Bipolar disorder (BD) is often under-recognized in non-psychiatric settings, especially in African Americans. The Mood Disorder Questionnaire (MDQ) is a screening instrument proposed to show adequate sensitivity and specificity for bipolar spectrum disorders. The current study is an examination of the usefulness of this instrument in a trauma exposed subgroup of mainly African American patients attending primary care clinics. Methods:, The sample is a part of a larger study exploring traumatic stress exposure and psychopathology. Consenting patients in 3 academically affiliated primary care clinics were asked to complete the MDQ. Ninety percent of the participants were African American. Diagnostic performance was determined in a trauma exposed subgroup by employing the Structured Clinical Interview for DSM-IV (SCID) as a gold standard. Results:, Of the total group of 579 participants, 178 (30.7%) screened positive for BD along with 77 (33.7%) of the 228 trauma exposed subjects who were SCID interviewed. Only 13 (27%) of the MDQ positives met SCID criteria for BD and were true positives. The sensitivity was 61.9% and the specificity was 69%, with a positive predictive value of 16.8% and a negative predictive value of 94.7%. Conclusions:, The MDQ was found to have low specificity in a predominately African American group of trauma exposed patients attending primary care. [source] Diagnostic performance of urine dipstick testing in children with suspected UTI: a systematic review of relationship with age and comparison with microscopyACTA PAEDIATRICA, Issue 4 2010R Mori Abstract Background:, Prompt diagnosis of urinary tract infection (UTI) in children is needed to initiate treatment but is difficult to establish without urine testing, and reliance on culture leads to delay. Urine dipsticks are often used as an alternative to microscopy, although the diagnostic performance of dipsticks at different ages has not been established systematically. Method:, Studies comparing urine dipstick testing in infants versus older children and urine dipstick versus microscopy were systematically searched and reviewed. Meta-analysis of available studies was conducted. Results:, Six studies addressed these questions. The results of meta-analysis showed that the performance of urine dipstick testing was significantly less in the younger children when compared with older children (p < 0.01). Positive likelihood ratio (LR) of both nitrite and leucocyte positive 38.54 [95% confidence interval (CI) 22.49,65.31], negative LR for both negative 0.13 (95% CI 0.07,0.25) are reasonably good, and those for young infants are less reliable [positive LR 7.62 (95% CI 0.95,51.85) and negative LR 0.34 (95% CI 0.66,0.15)]. Comparing microscopy and urine dipstick testing, using bacterial colony count on urine culture showed no significant difference between the two methods. Conclusion:, Urine dipstick testing is more effective for diagnosis of UTI in children over 2 years than for younger children. [source] Diagnostic performance of cardiac magnetic resonance imaging in coronary artery diseaseCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 2 2010Jussi P. Pärkkä Summary Background:, Cardiac magnetic resonance imaging (CMR) is a promising method for detecting coronary artery disease (CAD). The first reports of new diagnostic techniques indicated generally unrealistic diagnostic performance relying on retrospectively observed cut-off values of quantitative parameters. Although visual analysis of CMR is the most applicable method for clinical work, its diagnostic performance is not fully elucidated for study components such as wall motion, perfusion and late enhancement in patients with different severity of CAD. Methods:, A total of 30 subjects including 20 patients with CAD and 10 healthy volunteers were selected for the study. Of the patients, ten had stable CAD, five confirmed myocardial infarction (MI) without Q-waves in electrocardiogram (ECG) and five confirmed MI with Q-waves in ECG. All patients underwent coronary angiography and CMR for evaluating resting wall motion, rest and stress perfusion and late enhancement. Results:, Combining the data from the three CMR techniques, 12 out of 20 patients were correctly identified as having CAD, and all controls were found to be healthy. Sensitivity, specificity, accuracy, positive and negative predictive values were 60·0%, 100·0%, 73·0%, 100·0% and 55·6%, respectively. Of the CMR components, resting wall motion and late enhancement gave the most diagnostic yield. Conclusions:, We conclude that evaluation of CAD is feasible in patients with different severity of CAD using visually analysed CMR, especially when available CMR methodologies are combined together. [source] Cytological diagnosis of basal cell carcinoma and actinic keratosis, using Papanicolaou and May,Grünwald,Giemsa stained cutaneous tissue smearCYTOPATHOLOGY, Issue 5 2008E. Christensen Objective:, Cytology may become the diagnostic method of choice with the advent of new non-invasive treatments for non-melanoma skin cancer, as the sampling technique for cytology entails little tissue disfiguration. The aim of this study was to compare and evaluate the diagnostic performance of scrape cytology using two different cytological staining techniques, and to evaluate additional touch imprint cytology, with that of histopathology of basal cell carcinoma (BCC) and actinic keratosis (AK). Methods:, We investigated 50 BCC and 28 AK histologically verified lesions, from 41 and 25 patients, respectively. Two separate skin scrape samples and one touch imprint sample were taken from each lesion. The smears were stained with Papanicolaou (Pap) or May,Grünwald,Giemsa (MGG) stains. All cytological specimens were examined in random order by pathologists without knowledge of the histology. Cytodiagnostic results were compared with the histopathological report. Results:, Scrape cytodiagnosis agreed with histopathology in 48 (Pap) and 47 (MGG) of the 50 BCC cases, and in 26 of 28 (Pap) and 21 of 26 (MGG) AK cases, yielding sensitivities of 96%, 94%, 93% and 81%, respectively. No significant difference in sensitivity between the two staining methods was found but a trend towards higher Pap sensitivity for AK was noted (P = 0.10). Touch imprint cytology confirmed histopathology in 38 of the 77 cases of BCC and AK. Conclusion:, Cytological diagnosis with either Pap or MGG stain for BCC and AK is reliable, and differentiates well between BCC and AK. Imprint cytology proved to be non-diagnostic in half of the examined cases. [source] A CRITICAL LOOK AT PAP ADEQUECY: ARE OUR CRITERIA SATISFACTORY?CYTOPATHOLOGY, Issue 2006D.R. Bolick Liquid based Pap (LBP) specimen adequacy is a highly documented, yet poorly understood cornerstone of our GYN cytology practice. Each day, as cytology professionals, we make adequacy assessments and seldom wonder how the criteria we use were established. Are the criteria appropriate? Are they safe? What is the scientific data that support them? Were they clinically and statistically tested or refined to achieve optimal patient care? In this presentation, we will take a fresh look at what we know about Pap specimen adequacy and challenge some of the core assumptions of our daily practice. LBP tests have a consistent, well-defined surface area for screening, facilitating the quantitative estimates of slide cellularity. This provides an unprecedented opportunity to establish reproducible adequacy standards that can be subjected to scientific scrutiny and rigorous statistical analysis. Capitalizing on this opportunity, the TBS2001 took the landmark step to define specimen adequacy quantitatively, and set the threshold for a satisfactory LBP at greater than 5,000 well visualized squamous epithelial cells. To date, few published studies have attempted to evaluate the validity or receiver operator characteristics for this threshold, define an optimal threshold for clinical utility or assess risks of detection failure in ,satisfactory' but relatively hypocellular Pap specimens. Five years of cumulative adequacy and cellularity data of prospectively collected Pap samples from the author's laboratory will be presented, which will serve as a foundation for a discussion on ,Pap failure'. A relationship between cellularity and detection of HSIL will be presented. Risk levels for Pap failure will be presented for Pap samples of different cellularities. The effect of different cellularity criterion on unsatisfactory Pap rates and Pap failure rates will be demonstrated. Results from this data set raise serious questions as to the safety of current TBS2001 adequacy guidelines and suggest that the risk of Pap failure in specimens with 5,000 to 20 000 squamous cells on the slide is significantly higher than those assumed by the current criteria. TBS2001 designated all LBP to have the same adequacy criterion. Up to this point, it has been assumed that ThinPrep, SurePath, or any other LBP would be sufficiently similar that they should have the same adequacy criteria. Data for squamous cellularity and other performance characteristics of ThinPrep and SurePath from the author's laboratory will be compared. Intriguing data involving the recently approved MonoPrep Pap Test will be reviewed. MonoPrep clinical trial data show the unexpected finding of a strong correlation between abundance of endocervical component and the detection of high-grade lesions, provoking an inquiry of a potential new role for a quantitative assessment of the transition zone component. The current science of LBP adequacy criteria is underdeveloped and does not appear to be founded on statistically valid methods. This condition calls us forward as a body of practitioners and scientists to rigorously explore, clarify and define the fundamental nature of cytology adequacy. As we forge this emerging science, we will improve diagnostic performance, guide the development of future technologies, and better serve the patients who give us their trust. Reference:, Birdsong GG: Pap smear adequacy: Is our understanding satisfactory? Diagn Cytopathol. 2001 Feb; 24(2): 79,81. [source] Systematic review of methods to diagnose infection in foot ulcers in diabetesDIABETIC MEDICINE, Issue 4 2006S. O'Meara Abstract Aim, To undertake a systematic review of the diagnostic performance of clinical examination, sample acquisition and sample analysis in infected foot ulcers in diabetes. Methods, Nineteen electronic databases plus other sources were searched. To be included, studies had to fulfil the following criteria: (i) compare a method of clinical assessment, sample collection or sample analysis with a reference standard; (ii) recruit diabetic individuals with foot ulcers; (ii) present 2 × 2 diagnostic data. Studies were critically appraised using a 12-item checklist. Results Three eligible studies were identified, one each on clinical examination, sample collection and sample analysis. For all three, study groups were heterogeneous with respect to wound type and a small proportion of participants had foot ulcers due to diabetes. No studies identified an optimum reference standard. Other methodological problems included non-blind interpretation of tests and the time lag between index and reference tests. Individual signs or symptoms of infection did not prove to be useful tests when assessed against punch biopsy as the reference standard. The wound swab did not perform well when assessed against tissue biopsy. Semiquantitative analysis of wound swab might be a useful alternative to quantitative analysis. The limitations of these findings and their impact on recommendations from relevant clinical guidelines are discussed. Conclusion, Given the importance of this topic, it is surprising that only three eligible studies were identified. It was not possible to describe the optimal methods of diagnosing infection in diabetic patients with foot ulceration from the evidence identified in this systematic review. Diabet. Med. 23, 341,347 (2006) [source] Reliability and construct validity of the compatible MRI scoring system for evaluation of elbows in haemophilic childrenHAEMOPHILIA, Issue 2 2008A. S. DORIA Summary., We assessed the reliability and construct validity of the Compatible MRI scale for evaluation of elbows, and compared the diagnostic performance of MRI and radiographs for assessment of these joints. Twenty-nine MR examinations of elbows from 27 boys with haemophilia A and B [age range, 5,17 years (mean, 11.5)] were independently read by four blinded radiologists on two occasions. Three centres participated in the study: (Toronto, n = 24 examinations; Atlanta, n = 3; Cuiaba, n = 2). The number of previous joint bleeds and severity of haemophilia were reference standard measures. The inter-reader reliability of MRI scores was substantial (ICC = 0.73) for the additive (A)-scale and excellent (ICC = 0.83) for the progressive (P)-scale. The intrareader reliability was excellent for both P-scores (ICC = 0.91) and A-scores (ICC = 0.93). The total P- and A-scores correlated poorly (r = 0.36) or moderately (r = 0.54), but positively, with clinical-laboratory measurements. The total MRI scores demonstrated high accuracy for discrimination of presence or absence of arthropathy [P-scale, area-under-the-curve (AUC) = 0.94 ± 0.05; A-scale, AUC = 0.89 ± 0.06], as did the soft tissue scores of both scales (P-scale, AUC = 0.90 ± 0.06; A-scale, AUC = 0.86 ± 0.06). Areas-under-the-curve used to discriminate severe disease demonstrated high accuracy for both P-MRI scores (AUC = 0.83 ± 0.09) and A-MRI scores (AUC = 0.87 ± 0.09), but non-diagnostic ability to discriminate mild disease. Similar results were noted for radiographic scales. In conclusion, both MRI scales demonstrated substantial to excellent reliability and accuracy for discrimination of presence/absence of arthropathy, and severe/non-severe disease, but poor to moderate convergent validity for total scores and non-diagnostic discriminant validity for mild/non-mild disease. Compared with radiographic scores, MRI scales did not perform better for discrimination of severity of arthropathy. [source] Depression in dementia: a comparative and validation study of four brief scales in the elderly ChineseINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 5 2004Chee Kum Lam Abstract Aim The study aimed to determine: (i) the diagnostic accuracy of four brief depression scales, the Geriatric Depression Scale (GDS), Even Briefer Assessment Scale for Depression (EBAS DEP), Single Question and Cornell Scale for Depression in Dementia (Cornell) in an elderly Chinese population with varying dementia severity; and (ii) which scale had the best diagnostic performance. Method All four scales were administered to 88 elderly outpatients with dementia: 66 without and 22 with depression. Receiver Operating Characteristic (ROC) analysis was used to establish the optimal cut-off scores of the GDS, EBAS DEP and Cornell scales. The patients' dementia-severity was dichotomously categorized into mild and moderate-severe dementia, and the above analysis was repeated in both these groups to look at changes in the scales' diagnostic performance as dementia advances. Results The best diagnostic scale for detecting depression in dementia was the Cornell scale. Its optimal cut-off score was 6/7 (sensitivity 91.7%, specificity 80.0%) in the mild dementia group and 12/13 (sensitivity 70.0%, specificity 87.0%) in the more advanced dementia group. The optimal cut-off scores of the GDS and EBAS DEP also shifted to higher values when moving from the mild to the more advanced dementia groups, indicating the increasing difficulty on all these scales to detect depression with worsening cognitive impairment. The Single Question, however, was more robust with much less changes in its diagnostic parameters in both dementia cohorts: sensitivity 58.3%, specificity 90.0% for mild dementia, and 60.0 and 84.8%, respectively, for more advanced dementia. Conclusion An efficient strategy to diagnose depression in dementia amongst elderly Chinese patients is to administer the Single Question followed by, when necessary, the Cornell scale. Copyright © 2004 John Wiley & Sons, Ltd. [source] Diagnostic performance of the variant lymphocyte flag of the Abbott Cell-Dyn 4000 haematology analyserINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 1 2004J. J. M. L. Hoffmann Summary Background: In addition to differential cell counts, modern haematology analysers generate suspect flags if abnormal cells are detected. Reports on validation of suspect flags are scarce. We have routine experience with the Abbott Cell-Dyn 4000 analyser for over 5 years and have previously demonstrated the utility of the blast flag. Here we report a similar study on the performance of the analyser's Variant Lymphocyte (VL) flag. Aim of the study: Evaluation of the diagnostic performance of the Cell-Dyn 4000 VL flag, as compared with lymphocyte morphology in blood smears. In addition, we investigated the usefulness of the numerical VL flag confidence index as provided by the analyser. Materials and methods: All samples generating a VL flag were reviewed over a 5-month period. We also reviewed smears from patients with known lymphoid disorders, even if the analyser did not flag the sample. Two experienced investigators assessed lymphocyte morphology independently. Results: In total, 187 samples were included in the study, of which 183 had a VL flag and four had not. Of the 183 flagged samples, 83 appeared to have abnormal lymphocyte morphology and 100, normal lymphocyte morphology. The sensitivity of the VL flag for detecting abnormal lymphocytes was 0.95 and the positive predictive value was 0.44. Using ROC analysis of the VL flag confidence index, the area under the ROC curve was 0.58 (95% confidence interval 0.50,0.65). Conclusions: The Cell-Dyn VL flag has reasonable sensitivity but a high false-positive rate. In addition, its performance is insufficient for detecting clinically relevant abnormal lymphocytes. As the VL flag appeared to rely mainly on numerical criteria, it has no added value over numerical criteria defined by the laboratory. [source] Diagnostic performance of three-dimensional ultrasound extended imaging at scrotal mass lesionsINTERNATIONAL JOURNAL OF UROLOGY, Issue 11 2007Salah Elwagdy Objectives: High resolution two-dimensional ultrasound (2D US) difficulty in evaluation of some scrotal mass lesions is not frequent. The aim of the present study was to prospectively evaluate the diagnostic performance of three-dimensional ultrasound extended imaging (3D XI) in characterization of those lesions. Methods: The study protocol had the approval of the University's review board all participants' informed consents were obtained. The study included 28 selected patients (12 testicular and 16 para-testicular mass lesions) examined by 2D US and 3D XI applications including computed multi-slice view (MSV) and multi-resolution enhanced images (XI MR). Results were correlated with histopathological findings. Results: Two-dimensional ultrasound did not adequately characterize 28 patients out of 329 (8.5%). 3D XI interrogation was an easy procedure and distinctive of the pathological findings in 27 patients out of 28 (96.4%). The performance of XI MR with respect to characterization provided additional diagnostic information over MSV. Conclusions: The performance of 3D XI with respect to testicular mass characterization proved better than static 2D US. Subsequently, the results of this study suggest that the routine use of 2D US in diagnosis of scrotal mass lesions should preferably be upgraded to 3D XI methods. [source] Ambulatory or Home Measurement of Blood Pressure?JOURNAL OF CLINICAL HYPERTENSION, Issue 4 2009Philippe Gosse MD Ambulatory blood pressure monitoring (ABPM) and home blood pressure (HBPM) monitoring have been shown to be superior to conventional measurement of blood pressure in terms of reproducibility, relationship to the impact of high blood pressure on target organs, and the prediction of cardiovascular events. Nevertheless, these 2 techniques have yet to find their place in the diagnosis of hypertension and during evaluation of the efficacy of antihypertensive treatment. Although these 2 methods do not give identical results in approximately 20% of cases, their diagnostic performance and prognostic value are quite comparable. Although ABPM remains a valuable tool in clinical research, its utilization in routine clinical practice is limited by cost and availability. HBPM is increasingly employed for informed and well-managed patients, and it can help to improve control of the patient's blood pressure. Physicians involved in the management of hypertensive patients should be aware of its value in order to assist patients in their care. [source] Nasogastric Aspiration and Lavage in Emergency Department Patients with Hematochezia or Melena Without HematemesisACADEMIC EMERGENCY MEDICINE, Issue 2 2010Nicholas Palamidessi MD Abstract Objectives:, The utility of nasogastric aspiration and lavage in the emergency management of patients with melena or hematochezia without hematemesis is controversial. This evidence-based emergency medicine review evaluates the following question: does nasogastric aspiration and lavage in patients with melena or hematochezia and no hematemesis differentiate an upper from lower source of gastrointestinal (GI) bleeding? Methods:, MEDLINE, EMBASE, the Cochrane Library, and other databases were searched. Studies were selected for inclusion in the review if the authors had performed nasogastric aspiration (with or without lavage) in all patients with hematochezia or melena and performed esophagogastroduodenal endoscopy (EGD) in all patients. Studies were excluded if they enrolled patients with history of esophageal varices or included patients with hematemesis or coffee ground emesis (unless the data for patients without hematemesis or coffee ground emesis could be separated out). The outcome was identifying upper GI hemorrhage (active bleeding or high-risk lesions potentially responsible for hemorrhage) and the rate of complications associated with the nasogastric tube insertion. Quality of the included studies was assessed using standard criteria for diagnostic accuracy studies. Results:, Three retrospective studies met our inclusion and exclusion criteria. The prevalence of an upper GI source for patients with melena or hematochezia without hematemesis was 32% to 74%. According to the included studies, the diagnostic performance of the nasogastric aspiration and lavage for predicting upper GI bleeding is poor. The sensitivity of this test ranged from 42% to 84%, the specificity from 54% to 91%, and negative likelihood ratios from 0.62 to 0.20. Only one study reported the rate complications associated with nasogastric aspiration and lavage (1.6%). Conclusions:, Nasogastric aspiration, with or without lavage, has a low sensitivity and poor negative likelihood ratio, which limits its utility in ruling out an upper GI source of bleeding in patients with melena or hematochezia without hematemesis. ACADEMIC EMERGENCY MEDICINE 2010; 17:126,132 © 2010 by the Society for Academic Emergency Medicine [source] Chronic hepatitis: Role of diffusion-weighted imaging and diffusion tensor imaging for the diagnosis of liver fibrosis and inflammationJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 1 2008Bachir Taouli MD Abstract Purpose To determine the diagnostic performance of liver apparent diffusion coefficient (ADC) measured with conventional diffusion-weighted imaging (CDI) and diffusion tensor imaging (DTI) for the diagnosis of liver fibrosis and inflammation. Materials and Methods Breathhold single-shot echo-planar imaging CDI and DTI with b-values of 0 and 500 second/mm2 was performed in 31 patients with chronic liver disease and 13 normal volunteers. Liver biopsy was performed in all patients with liver disease with a median delay of two days from MRI. Fibrosis and inflammation were scored on a 5-point scale (0,4). Liver ADCs obtained with CDI and DTI were compared between patients stratified by fibrosis stage and inflammation grade. Receiver operating characteristic (ROC) curve analyses were conducted to evaluate the utility of the ADC measures for prediction of fibrosis and inflammation. Results Patients with liver fibrosis and inflammation had significantly lower liver ADC than subjects without fibrosis or inflammation with CDI and DTI. For prediction of fibrosis stage , 1 and stage , 2, area under the ROC curve (AUC) of 0.848 and 0.783, sensitivity of 88.5% to 73.7%, and specificity of 73.3% to 72.7% were obtained, for ADC ,1.40 × 10,3 mm2/second and ,1.30 × 10,3 mm2/second (using CDI), respectively. For prediction of inflammation grade , 1, AUC of 0.825, sensitivity of 75.0%, and specificity of 78.6% were obtained using ADC , 1.30 × 10,3 mm2/second (using CDI). CDI performed better than DTI for diagnosis of fibrosis and inflammation. Conclusion Liver ADC can be used to predict liver fibrosis and inflammation with acceptable sensitivity and specificity. J. Magn. Reson. Imaging 2008;28:89,95. © 2008 Wiley-Liss, Inc. [source] Detection of choline signal in human breast lesions with chemical-shift imagingJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 5 2008Hyeon-Man Baek PhD Abstract Purpose To investigate the application of MR spectroscopy using chemical-shift imaging (CSI) for characterizing human breast lesions at 1.5T, and to evaluate the diagnostic performance using ROC (receiver operating characteristics) analysis. Materials and Methods Thirty-six patients (35,73 years old, mean 52), with 27 malignant and 9 benign lesions, underwent anatomical imaging, dynamic contrast-enhanced MR imaging, and CSI. The ROC analysis was performed and the cutoff point yielding the highest accuracy was found to be a choline (Cho) signal-to-noise ratio (SNR) >3.2. Results The mean Cho SNR was 2.8 ± 0.8 (range, 1.8,4.3) for the benign group and 5.9 ± 3.4 (2.1,17.5) for the malignant group (P = 0.01). Based on the criterion of Cho SNR >3.2 as malignant, CSI correctly diagnosed 22 of 27 malignant lesions and 7 of 9 benign lesions, resulting in a sensitivity of 81%, specificity of 78%, and overall accuracy of 81%. If the criterion was set higher at Cho SNR >4.0 the specificity improved to 89% but sensitivity was lowered to 67%. Conclusion The ROC analysis presented in this work could be used to set an objective diagnostic criterion depending on preferred emphasis on sensitivity or specificity. J. Magn. Reson. Imaging 2008;27:1114,1121. © 2008 Wiley-Liss, Inc. [source] Differentiation of intraductal papillary mucinous neoplasms from other pancreatic cystic masses: Comparison of multirow-detector CT and MR imaging using ROC analysisJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 1 2007Su Jin Song MD Abstract Purpose To compare the diagnostic performance of multirow-detector computed tomography (MDCT) and magnetic resonance imaging (MRI) in the differentiation of intraductal papillary mucinous neoplasms (IPMNs) from other pancreatic cystic masses. Materials and Methods A total of 53 patients with pathologically proven pancreatic cystic lesions who had undergone MDCT and MRI were included in this study. Two radiologists analyzed the morphologic features of the lesions and graded the lesion conspicuity on each examination. The readers assigned their confidence level regarding the differentiation of IPMN from other lesions and predicting ductal communication of the lesion. The radiologists' diagnostic confidence was compared using receiver operating characteristic (ROC) analysis. Results The Az values for each observer for predicting ductal communication of the lesion and differentiating IPMN from other lesions were as follows: For MRI they were respectively 0.949 and 0.995 for reader 1, and 0.916 and 0.932 for reader 2. For MDCT they were respectively 0.790 and 0.875 for reader 1, and 0.774 and 0.850 for reader 2. In addition, for differentiating IPMNs from other lesions, MRI was significantly more accurate than MDCT (P < 0.05) for one observer, but for the other observer there was no significant difference between the two examinations (P = 0.059). For predicting ductal communication of the cystic lesions for both observers, MRI was significantly more accurate than MDCT (P < 0.05). The weighted , values indicate good agreement (, = 0.61) between observers for MDCT, and excellent agreement (, = 0.82) for MRI. Conclusion Pancreatic MRI shows better diagnostic performance than MDCT for differentiating IPMNs from other cystic lesions of the pancreas. J. Magn. Reson. Imaging 2007;26:86,93. © 2007 Wiley-Liss, Inc. [source] Transvaginal Hysterosalpingo-Contrast Sonography (HyCoSy) Compared with ChromolaparoscopyJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 1 2000Dr. Somchai Tanawattanacharoen Abstract Objective: To compare the efficacy and safety of HyCoSy with chromolaparoscopy for the diagnosis of tubal occlusion and uterine abnormalities. Methods: Sixty infertile women in whom the cause of infertility was thought to be tubal occlusion or uterine abnormalities and who satisfied the inclusion and exclusion criteria as specified in the study protocol were included. HyCoSy was performed during the first half of the menstrual cycle at least 24 hours prior to chromolaparoscopy. The results from both HyCoSy and chromolaparoscopy were compared in assessing tubal occlusion and uterine pathology. Results: For the evaluation of fallopian tubes, we found corresponding results between HyCoSy and chromolaparoscopy in 80.0%. The agreement between both procedures in assessing the uterine pathology was 80.4%. Twenty-two women experienced adverse events. The most common complaint was pelvic pain. Other events encountered were: nausea (3 women) and vaginal bleeding (2 women). All events were thought to be not related to the study drug. Conclusion: HyCoSy showed good diagnostic performance in the evaluation of the fallopian tubes and uterus in infertile women. The adverse events reported in this study are minor and procedure-related (catheter insertion) rather than the trial substance. [source] Noninvasive Diagnosis of Large Esophageal Varices by Fibroscan: Strong Influence of the Cirrhosis EtiologyALCOHOLISM, Issue 7 2010Eric Nguyen-Khac Background:, Large esophageal varices (LOV) were diagnosed by endoscopy in patients with cirrhosis. Noninvasive method would be valuable. Aims:, To evaluate the diagnostic performance of Fibroscan for LOV prediction and to investigate the prognostic value of liver stiffness (LS) in cirrhosis. Patients and Methods:, One hundred and eighty-three patients with cirrhosis (103 alcohol, 58 viral, and 22 others) underwent an endoscopy and a Fibroscan. Of those patients, 41 (22.4%) had LOV. Results:, Median LS was 33.66 kPa (range: 12,75), higher in patients with LOV than those without (51.24 ± 1.61 vs. 29.81 ± 1.82 kPa, p < 0.0001), and in alcoholic than nonalcoholic (40.39 ± 1.75 vs. 25.73 ± 1.82, p < 0.0001). In whole population, a LS ,48 kPa predicted LOV with sensitivity, specificity, positive, negative predictive values (PPV, NPV) of 73.2, 73.2, 44.1, and 90.4%, respectively, and an area under ROC curve (AUROC) of 0.75 (CI 95%: 0.69,0.82). For alcoholic cirrhosis, LS was ,47.2 kPa with sensitivity, specificity, PPV, NPV of 84.6, 63.6, 44, and 92.5%, respectively, AUROC 0.77 (0.68,0.85). For viral cirrhosis, a LS ,19.8 kPa generated diagnostic values of 88.9, 55.1, 26.7, and 96.4% and 0.73 (0.60,0.84). Sixteen (8.75%) patients died at 1 year. In multivariate analysis, LS was not predictive of mortality. Conclusions:, Etiology of cirrhosis has strong impact on LS cutoff for diagnosis of LOV. Studies should be performed with homogenous cirrhosis etiology. [source] Sensitivity of Bedside Ultrasound and Supine Anteroposterior Chest Radiographs for the Identification of Pneumothorax After Blunt TraumaACADEMIC EMERGENCY MEDICINE, Issue 1 2010R. Gentry Wilkerson MD Abstract Objectives:, Supine anteroposterior (AP) chest radiographs in patients with blunt trauma have poor sensitivity for the identification of pneumothorax. Ultrasound (US) has been proposed as an alternative screening test for pneumothorax in this population. The authors conducted an evidence-based review of the medical literature to compare sensitivity of bedside US and AP chest radiographs in identifying pneumothorax after blunt trauma. Methods:, MEDLINE and EMBASE databases were searched for trials from 1965 through June 2009 using a search strategy derived from the following PICO formulation of our clinical question: patients included adult (18 + years) emergency department (ED) patients in whom pneumothorax was suspected after blunt trauma. The intervention was thoracic ultrasonography for the detection of pneumothorax. The comparator was the supine AP chest radiograph during the initial evaluation of the patient. The outcome was the diagnostic performance of US in identifying the presence of pneumothorax in the study population. The criterion standard for the presence or absence of pneumothorax was computed tomography (CT) of the chest or a rush of air during thoracostomy tube placement (in unstable patients). Prospective, observational trials of emergency physician (EP)-performed thoracic US were included. Trials in which the exams were performed by radiologists or surgeons, or trials that investigated patients suffering penetrating trauma or with spontaneous or iatrogenic pneumothoraces, were excluded. The methodologic quality of the studies was assessed. Qualitative methods were used to summarize the study results. Data analysis consisted of test performance (sensitivity and specificity, with 95% confidence intervals [CIs]) of thoracic US and supine AP chest radiography. Results:, Four prospective observational studies were identified, with a total of 606 subjects who met the inclusion and exclusion criteria. The sensitivity and specificity of US for the detection of pneumothorax ranged from 86% to 98% and 97% to 100%, respectively. The sensitivity of supine AP chest radiographs for the detection of pneumothorax ranged from 28% to 75%. The specificity of supine AP chest radiographs was 100% in all included studies. Conclusions:, This evidence-based review suggests that bedside thoracic US is a more sensitive screening test than supine AP chest radiography for the detection of pneumothorax in adult patients with blunt chest trauma. ACADEMIC EMERGENCY MEDICINE 2010; 17:11,17 © 2010 by the Society for Academic Emergency Medicine [source] Diagnostic Accuracy of Emergency Doppler Echocardiography for Identification of Acute Left Ventricular Heart Failure in Patients with Acute Dyspnea: Comparison with Boston Criteria and N-terminal Prohormone Brain Natriuretic PeptideACADEMIC EMERGENCY MEDICINE, Issue 1 2010Peiman Nazerian MD Abstract Objectives:, Echocardiography is a fundamental tool in the diagnosis of acute left ventricular heart failure (aLVHF). However, a consultative exam is not routinely available in every emergency department (ED). The authors investigated the diagnostic performance of emergency Doppler echocardiography (EDecho) performed by emergency physicians (EPs) for the diagnosis of aLVHF in patients with acute dyspnea. Methods:, A convenience sample of acute dyspneic patients was evaluated. For each patient, the Boston criteria score for heart failure was calculated, and N-terminal prohormone brain natriuretic peptide (NT-proBNP) and EDecho were contemporaneously performed. Four investigators, after a limited echocardiography course, performed EDechos and evaluated for a "restrictive" pattern on pulsed Doppler analysis of mitral inflow and reduced left ventricular (LV) ejection fraction. The final diagnosis, established after reviewing all patient clinical data except NT-proBNP and EDecho results, served as the criterion standard. Results:, Among 145 patients, 64 (44%) were diagnosed with aLVHF. The median time needed to perform EDecho was 4 minutes. Pulsed Doppler analysis was feasible in 125 patients (84%). The restrictive pattern was more sensitive (82%) and specific (90%) than reduced LV ejection fraction and more specific than the Boston criteria and NT-proBNP for the diagnosis of aLVHF. Considering noninterpretable values of the restrictive pattern and uncertain values ("gray areas") of Boston criteria (4 < Boston criteria score < 7) and of NT-proBNP (300 < NT-proBNP < 2,200 pg/mL) as false results, the accuracy of the restrictive pattern in the overall population was 75%, compared with accuracy of 49% for both NT-proBNP and Boston criteria. Conclusions:, EDecho, particularly pulsed Doppler analysis of mitral inflow, is a rapid and accurate diagnostic tool in the evaluation of patients with acute dyspnea. ACADEMIC EMERGENCY MEDICINE 2010; 17:18,26 © 2010 by the Society for Academic Emergency Medicine [source] Systematic review: accuracy of symptom-based criteria for diagnosis of irritable bowel syndrome in primary careALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 7 2009P. JELLEMA Summary Background, Despite the trend towards making a positive diagnosis of irritable bowel syndrome (IBS), many health care providers approach IBS as a diagnosis of exclusion. Aim, To summarize available evidence on the diagnostic performance of symptom-based IBS criteria in excluding organic diseases, and of individual signs and symptoms in diagnosing IBS and to additionally assess the influence of sources of heterogeneity on diagnostic performance. Methods, We searched PubMed and EMBASE and screened references. Studies were selected if the design was a primary diagnostic study; the patients were adults consulting because of non-acute abdominal symptoms; the diagnostic test included an externally validated set of IBS criteria, signs, or symptoms. Data extraction and quality assessment were performed by two reviewers independently. The review adhered to the most recent guidelines as described in the Cochrane Diagnostic Reviewers' Handbook. Results, A total of 25 primary diagnostic studies were included in the review. The performance of symptom-based criteria in the exclusion of organic disease was highly variable. Patients fulfilling IBS criteria had, however, a lower risk of organic diseases than those not fulfilling the criteria. Conclusions, With none of the criteria showing sufficiently homogeneous and favourable results, organic disease cannot be accurately excluded by symptom-based IBS criteria alone. However, the low pre-test probability of organic disease especially among patients who meet symptom-based criteria in primary care argues against exhaustive diagnostic evaluation. We advise validation of the new Rome III criteria in primary care populations. [source] 13C-methacetin breath test as a quantitative liver function test in patients with chronic hepatitis C infection: continuous automatic molecular correlation spectroscopy compared to isotopic ratio mass spectrometryALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 2 2007O. GOETZE Summary Background The 13C-methacetin breath test (MBT) has been proposed for the non-invasive evaluation of hepatic microsomal activity. Aim To test a new continuous breath analysis system (BreathID) in comparison with gold-standard isotopic ratio mass spectrometry (IRMS) in patients with chronic hepatitis C infection and to assess the diagnostic performance of these validation data compared with liver biopsy for the quantification of liver fibrosis. Methods Fifty patients at different METAVIR stages received 75 mg of 13C-methacetin. Breath isotopic ratio was analysed over 90 min by BreathID (one sample/3 min; BreathID) and IRMS (one sample/10 min). Results were expressed as delta over baseline [DOB (%)] at each time interval and maximal DOB [DOBmax(%)]. Results A high linear association between both methods was observed (R2 = 0.95, P < 0.001). For all DOB and DOBmax, the limits of agreement by Bland,Altman analysis were within the predefined maximal width of s.d. <2.5%. MBT parameters in patients with high-grade fibrosis were different from patients with low-grade fibrosis (P < 0.001). Conclusion The MBT obtained by an easy to operate, automated BreathID provides results comparable with standard IRMS and differentiates fibrosis grades in patients with chronic hepatitis C infection. [source] Automatic generation and evaluation of sparse protein signatures for families of protein structural domainsPROTEIN SCIENCE, Issue 1 2005Matthew J. Blades Abstract We identified key residues from the structural alignment of families of protein domains from SCOP which we represented in the form of sparse protein signatures. A signature-generating algorithm (SigGen) was developed and used to automatically identify key residues based on several structural and sequence-based criteria. The capacity of the signatures to detect related sequences from the SWISSPROT database was assessed by receiver operator characteristic (ROC) analysis and jack-knife testing. Test signatures for families from each of the main SCOP classes are described in relation to the quality of the structural alignments, the SigGen parameters used, and their diagnostic performance. We show that automatically generated signatures are potently diagnostic for their family (ROC50 scores typically >0.8), consistently outperform random signatures, and can identify sequence relationships in the "twilight zone" of protein sequence similarity (<40%). Signatures based on 15%,30% of alignment positions occurred most frequently among the best-performing signatures. When alignment quality is poor, sparser signatures perform better, whereas signatures generated from higher-quality alignments of fewer structures require more positions to be diagnostic. Our validation of signatures from the Globin family shows that when sequences from the structural alignment are removed and new signatures generated, the omitted sequences are still detected. The positions highlighted by the signature often correspond (alignment specificity >0.7) to the key positions in the original (non-jack-knifed) alignment. We discuss potential applications of sparse signatures in sequence annotation and homology modeling. [source] Comparing serum and pleural fluid pro-brain natriuretic peptide (NT-proBNP) levels with pleural-to-serum albumin gradient for the identification of cardiac effusions misclassified by Light's criteriaRESPIROLOGY, Issue 5 2007José M. PORCEL Background and objectives: To assess the diagnostic performance of the amino-terminal fragment of pro-brain natriuretic peptide (NT-proBNP) in pleural fluid and serum for the identification of pleural effusions owing to heart failure, and to determine if these measurements allow better categorization of cardiac effusions that have been misclassified by Light's criteria, than do serum-pleural fluid albumin and protein gradients. Methods: The study prospectively evaluated NT-proBNP in serum and pleural fluid from patients with effusions owing to heart failure (n = 53) and other causes (n = 40). Measurements were made of levels of NT-proBNP by an electrochemiluminiscence immunoassay, and serum-pleural fluid protein and albumin gradients. Results: Using a cut-off value of 1500 pg/mL for serum and pleural samples, the accuracy of NT-proBNP for identifying pleural effusions from cardiac causes was 89% and 90%, respectively. The area under the receiver operating characteristic curve for the diagnosis of pleural effusions from heart failure was similar for pleural fluid (0.931, 95% CI: 0.871,0.991) and serum (0.919, 95% CI: 0.855,0.984) NT-proBNP. Six (75%) of eight patients with cardiac effusions that were misclassified as exudates by Light's criteria would have been correctly categorized by either NT-proBNP or the albumin gradient, whereas only four (50%) would have been correctly classified by the protein gradient. Conclusions: NT-proBNP is a useful marker for the diagnosis of pleural effusions from heart failure when measured in either serum or pleural fluid. At a cut-off of 1500 pg/mL, NT-proBNP is at least as accurate as the albumin gradient to correctly identify cardiac effusions misclassified as exudates by standard criteria, but at much higher cost. [source] | ||||||||||||||||||||||||||||