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At least 595 records · Page 33Linked to original sources
PubMed1999

Metastases from non-small cell lung cancer: mediastinal staging in the 1990s--meta-analytic comparison of PET and CT.

PURPOSE: To meta-analytically compare 2-[fluorine 18]fluoro-2-deoxy-D-glucose positron emission tomography (PET) and computed tomography (CT) for the demonstration of mediastinal nodal metastases in patients with non-small cell lung cancer. MATERIALS AND METHODS: English-language reports on the diagnostic performance of PET (14 studies, 514 patients) and/or CT (29 studies, 2,226 patients) for demonstration of mediastinal nodal metastases from NSCLC were selected by using the MEDLINE database. In eligible studies, an objective diagnostic standard was used, data were presented to allow recalculation of contingency tables, and established diagnostic criteria were used for abnormal test results. Summary receiver operating characteristic (ROC) curves were calculated. RESULTS: Pooled point estimates of diagnostic performance and summary ROC curves indicated that PET was significantly more accurate than CT for demonstration of nodal metastases (P < .001). Mean sensitivity and specificity (+/- 95% CI) were 0.79 +/- 0.03 and 0.91 +/- 0.02, respectively, for PET and 0.60 +/- 0.02 and 0.77 +/- 0.02, respectively, for CT. The log odds ratios were 1.79 (95% CI: 1.49, 2.09) for CT and 3.77 (95% CI: 2.77, 4.77) for PET (P < .001). Subgroup analyses did not alter findings. CONCLUSION: PET is superior to CT for mediastinal staging of non-small cell lung cancer, independent of performance index or clinical context of PET imaging.

Carcinoma, Non-Small-Cell Lung↗
PubMed2005

Arthroscopy -- a potential "gold standard" for the diagnosis of the chondropathy of early osteoarthritis.

OBJECTIVES: The aims of this study were to: 1. Evaluate the performance of arthroscopy for the diagnosis of chondropathy and to compare it to that of direct non-arthroscopic assessments; 2. Determine intra-observer reliability of arthroscopic assessments; 3. Evaluate the effects of the arthroscopic video quality and probing upon diagnostic performance. DESIGN: The ovine medial meniscectomy (MMx) model of early osteoarthritis (OA) was used assuming that pre-MMx articular cartilage (AC) was "normal" and post-MMx AC "chondropathic". Video recordings of arthroscopic assessments of each stifle compartment were evaluated. Scores were given for the quality of the video and the amount of probing. The diagnostic performances of dynamic shear modulus (G), light microscopic assessment and superficial zone collagen birefringence assessments were evaluated and compared to that of arthroscopy. Intra-observer reliability of arthroscopic assessments was also evaluated. RESULTS: Arthroscopic assessments had high sensitivity (91-100%), specificity (62-88%) and accuracy (75-93%) for the diagnosis of chondropathy 16 weeks after MMx. Arthroscopy compared favourably with the direct non-arthroscopic assessments in the lateral compartment and was found to have extremely high intra-observer reliability (kappa 0.78-1.00). The quality of arthroscopic video recordings and the amount of probing did not significantly influence accuracy or reliability. CONCLUSIONS: Arthroscopy performs as well as direct non-arthroscopic assessments of AC for diagnosis of early OA. These results suggest that arthroscopy can be used as a "gold standard" for the validation of non-invasive assessments like magnetic resonance imaging and that arthroscopic diagnosis can be based on small amounts of video footage without AC probing.

Animals↗
PubMed1999

Value of additional two-hour myoglobin for the diagnosis of myocardial infarction in the emergency department.

Myoglobin has been described as an early marker of myocardial injury. It increases within 1 to 3 hours of myocardial injury, and falls back to normal early after the event. Few data suggest that myoglobin can be used to triage patients with chest pain. To assess the diagnostic utility of second myoglobin levels drawn within 2 to 3 hours after presentation to the emergency department for detecting myocardial infarction, we prospectively collected myoglobin levels in 368 patients aged > or = 30 years who were admitted with chest pain. Myoglobin levels were measured at admission and 2 to 3 hours later. Sensitivity and specificity for detecting acute myocardial infarction for a twofold increase in myoglobin level from baseline were 39% and 98%, respectively. The early diagnostic performance of myoglobin at admission, the second level drawn 2 to 3 hours later, and creatine kinase-MB mass drawn at admission were similar (receiver-operating characteristic curves 0.80, 0.86, and 0.85). The diagnostic performance of each of these markers was significantly superior to the absolute change from baseline to second myoglobin (receiver-operating characteristic curve 0.77). In patients who presented within 4 hours of symptom onset, myoglobin drawn 2 to 3 hours later had the highest yield for detecting myocardial infarction. These results suggest that serial myoglobin measurement aiming to detect changes over time is not superior to single marker determinations. Myoglobin measured in 2 to 3 hours from admission may be helpful in triaging patients who present within 4 hours from onset of symptoms.

Creatine Kinase↗
PubMed2006

Neutrophil CD64 is an improved indicator of infection or sepsis in emergency department patients.

CONTEXT: Sepsis, affecting millions of individuals annually with an associated high mortality rate, is among the top 10 causes of death. In addition, improvements in diagnostic tests for detecting and monitoring sepsis and infection have been limited in the last 25 years. Neutrophil CD64 expression has been proposed as an improved diagnostic test for the evaluation of infection and sepsis. OBJECTIVE: To evaluate the diagnostic performance of a quantitative flow cytometric assay for leukocyte CD64 expression in comparison with the standard tests for infection/sepsis in an ambulatory care setting. DESIGN: Prospective analysis of 100 blood samples from patients from an emergency department setting in a 965-bed tertiary care suburban community hospital was performed for neutrophil CD64 expression, C-reactive protein, erythrocyte sedimentation rate, and complete blood count. The laboratory findings were compared with a clinical score for the likelihood of infection/sepsis, which was obtained by a blinded retrospective chart review. RESULTS: The diagnostic performance, as gauged by the clinical score, varied with neutrophil CD64 (sensitivity 87.9%, specificity 71.2%, efficiency 76.8%) and outperformed C-reactive protein (sensitivity 88.2%, specificity 59.4%, efficiency 69.4%), absolute neutrophil count (sensitivity 60.0%, specificity 50.8%, efficiency 53.8%), myeloid left shift (sensitivity 68.2%, specificity 76.3%, efficiency 73.3%), and sedimentation rate (sensitivity 50.0%, specificity 65.5%, efficiency 61.0%). CONCLUSION: Neutrophil CD64 expression quantitation provides improved diagnostic detection of infection/sepsis compared with the standard diagnostic tests used in current medical practice.

Blood Sedimentation↗
PubMed2006

Evaluation of the Binax NOW Streptococcus pneumoniae urinary antigen assay in intensive care patients hospitalized for pneumonia.

OBJECTIVE: To evaluate the diagnostic performance of Binax Now S. pneumoniae urinary antigen rapid immunochromatographic membrane test (ICT) for patients with suspicion of community-acquired pneumonia hospitalized in intensive care and to assess the impact of prior antibiotics on its diagnostic performance. DESIGN AND SETTING: Retrospective study in a medicosurgical ICU in a 700-bed general hospital. PATIENTS: Charts of patients with ICT performed (result blinded) were reviewed between May 2002 and July 2004. ICT has been performed in 140 of the 1,006 patients hospitalized in the unit; two-thirds had received antibiotics prior to admission. MEASUREMENTS AND RESULTS: Diagnosis of pneumonia was made according to usual criteria. All patients had at least one microbiological test. Pneumonia diagnosis confirmed in 108 patients including 32 pneumococcal. ICT was positive in 23 of 32 patients with pneumococcal pneumonia, in 11 of 108 without, and in none of the 32 patients without pneumonia, resulting in sensitivity, specificity, and positive and negative predictive values of, respectively: 72%, 90%, 68% and 92%. Positive likelihood ratios were comparable among patients with or without prior antibiotics (respectively 6 and 12 for 7 in the overall population). CONCLUSIONS: This first clinical evaluation of ICT in intensive care patients hospitalized for suspicion of community-acquired pneumonia, demonstrated performance in accordance with published data even in the case of prior antibiotics. Its clinical interest and impact on antibiotics policy remain to be refined.

Adult↗
PubMed1997

Focal hepatic lesions: effect of three-dimensional wavelet compression on detection at CT.

PURPOSE: To evaluate the effect of three-dimensional, wavelet-based compression on the detection of focal hepatic lesions at computed tomography (CT). MATERIALS AND METHODS: CT images obtained in 69 patients with focal hepatic lesions were studied (35 consecutive cases and 34 cases selected to be difficult on the basis of lesion size or contrast). Image data were compressed by means of a three-dimensional, wavelet-based algorIthm at ratios of 10:1, 15:1, and 20:1. Normal and abnormal sections (on original and compressed images) were reviewed by using an interactive workstation. Four readers rated the presence or absence of a lesion with a five-point scale. RESULTS: At receiver operating characteristic analysis, no statistically significant difference was detected for all cases considered together. Differences approached but did not reach statistical significance for the diagnostic performance of one reader with compressed images (15:1, P = .054; 20:1, P = .051). For the subset of difficult cases, a significant difference was observed with 20:1 compressed images for one reader (P = .026). Diagnostic performance of readers was less certain in normal than in abnormal cases with both original and compressed images (difference was significant for 15:1 [P = .035] and 20:1 [P < .0001] compressed images). CONCLUSION: Three-dimensional wavelet compression is satisfactory at ratios of at least 10:1. Additional studies with a larger sample would help confirm findings with higher ratios.

Cysts↗
PubMed2006

Utility of N-terminal pro-B-type natriuretic peptide to differentiate cardiac diseases from noncardiac diseases in young pediatric patients.

BACKGROUND: Previous studies comparing children with cardiac disease with children with lung disease or healthy children indicated that natriuretic peptides are promising markers in pediatric patients. The aim of this study was to further clarify the diagnostic usefulness of N-terminal pro-B-type natriuretic peptide (NT-proBNP) measurements in a less preselected population of children younger than 3 years, a population in which clinical symptoms are frequently unspecific. METHODS: NT-proBNP concentrations (Roche Diagnostics) were measured in sera of 142 pediatric patients (age range, 33-1070 days) presenting at the Gynaecologic and Pediatric Hospital (Linz, Austria) between January 2003 and January 2004. ROC curve analysis for the diagnostic performance of NT-proBNP, the Mann-Whitney U-test for group comparison, and linear regression analysis for influencing factors were performed. RESULTS: NT-proBNP concentrations were significantly increased in infants with cardiac diseases [median (25th-75th percentile), 3681 (1045-13557) ng/L; n = 23] compared with infants with other diseases [241 (116-542) ng/L; n = 119], and ROC analysis revealed good performance for NT-proBNP in differentiating between infants with and without cardiac diseases [mean area under the curve (AUC) with 95% confidence interval (CI), 0.87 (0.76-0.94)]. A subgroup analysis of exactly age- and sex-matched infants was performed, which revealed results comparable to those for the whole study population [mean (95% CI) AUC, 0.84 (0.68-0.93)]. CONCLUSION: In a heterogeneous group of pediatric patients < 3 years of age, NT-proBNP showed good diagnostic performance to distinguish between cardiac diseases and various noncardiac diseases.

Brain Diseases↗
PubMedDate not supplied

Using recombinant human thyroid-stimulating hormone for the diagnosis of recurrent thyroid cancer.

BACKGROUND: Recombinant human thyroid-stimulating hormone (rhTSH) has been suggested as a diagnostic agent in the diagnosis of recurrent thyroid cancer, instead of the current practice of thyroid hormone (THT) withdrawal. METHODS: An evidenced-based literature review was used as the basis for a cost-utility, decision-analytic model. Outcome measures were safety, efficacy (diagnostic performance and quality of life) and cost effectiveness of rhTSH. RESULTS: The literature search identified six comparative studies of rhTSH versus THT withdrawal. The most common adverse events associated with the use of rhTSH were headache (3.5-11.1%) and nausea (7.7-17%). When used as a diagnostic agent, the unadjusted sensitivity and specificity for rhTSH were 87% and 95%, respectively. Thus the use of rhTSH instead of THT withdrawal would result in a reduction in diagnostic accuracy, with 11% of patients' disease status being misclassified. Use of rhTSH resulted in a higher quality of life in the period prior to diagnostic testing than THT withdrawal (P < 0.001). When the impact of diagnostic performance, patient compliance to follow-up and modified quality of life were modelled over a 5 year time-frame, the incremental cost per QALY of rhTSH relative to THT withdrawal was $51 344.42. CONCLUSIONS: The use of rhTSH as a diagnostic agent appears to be safe but less diagnostically accurate and less cost-effective (on whole of healthcare cost basis) when used in the follow-up of patients with thyroid cancer who have had a previous negative radioiodine scan after thyroid hormone withdrawal.

Decision Support Techniques↗
PubMed1995

A study of biochemical markers of reperfusion early after thrombolysis for acute myocardial infarction. The PERM Study Group. Prospective Evaluation of Reperfusion Markers.

BACKGROUND: In acute myocardial infarction (AMI), early noninvasive identification of patients with occluded infarct-related arteries (IRAs) after thrombolysis has important prognostic and therapeutic implications. The aims of this study were to evaluate biochemical methods for the early diagnosis of patency after thrombolysis prospectively and to establish the optimal diagnostic criteria retrospectively. METHODS AND RESULTS: In 97 patients with AMI treated with thrombolytic agents < or = 6 hours after the onset of symptoms, myoglobin, troponin T, creatine kinase, the MB isoenzyme and MM isoforms of creatine kinase were measured just before thrombolysis began and 90 minutes later. IRA patency was assessed by means of 90-minute coronary angiography. For each marker, compared with the expected sensitivity and specificity based on published thresholds for the diagnosis of patency, the observed values were consistently lower but were markedly improved in a subset of patients treated > 3 hours after the onset of symptoms. With receiver-operator characteristic curve analysis of the slopes of increase and relative increases in each marker over 90 minutes, the best diagnostic performance was achieved by use of the relative increase in myoglobin, troponin T, and MM3/MM1 creatine kinase isoforms in patients treated > 3 hours after onset (areas under the curve of 0.84, 0.83, and 0.85, respectively). CONCLUSIONS: Effective early noninvasive diagnosis of patency after thrombolysis is possible in patients treated > 3 hours after symptom onset by use of criteria derived from the relative increase over 90 minutes in plasma markers, particularly myoglobin, troponin T, and MM3/MM1 creatine kinase isoforms. The diagnostic performance of the relative increase in myoglobin appears to be less susceptible to small changes in the diagnostic threshold value.

Biomarkers↗
PubMed2006

New insights into the diagnostic accuracy of complexed and total prostate specific antigen using discordance analysis characteristics.

PURPOSE: Comparison of diagnostic performances of total and complexed prostate specific antigen (tPSA, cPSA) using ROC curve analysis resulted in controversial interpretations. To overcome the biases due to analysis of subgroups selected by concentration ranges of only 1 marker the novel approach named discordance analysis characteristics is presented. MATERIALS AND METHODS: DAC method includes only patients who are discordantly categorized by the tests under investigation using cutoffs with identical sensitivity. Within those patients parameters describing diagnostic accuracy are calculated. The systematic nature of the results is confirmed by varying the cutoffs. DAC method is demonstrated considering the example of cPSA and tPSA data from 2 prostate cancer studies with a total of 1,624 patients (study A and B, of 283 and 565 with as well as 417 and 359 men without prostate cancer, respectively). PSA concentrations were measured using the Bayer assays. RESULTS: The DAC method proved that cPSA outperformed tPSA regarding the criteria diagnostic specificity and positive predictive value. Among discordantly tested patients cPSA detected patients with an about 2-fold higher risk to have prostate cancer and with a 3.6 to 5.5-fold better specificity than tPSA. Using cPSA instead of tPSA more than 10% of unnecessary biopsies could be avoided in the tPSA range of 3 to 5 ng/ml. CONCLUSIONS: The superior diagnostic performance of cPSA in comparison with tPSA warrants the recommendation to use cPSA as initial test in prostate cancer diagnostics. The DAC method is generally recommended to replace comparative ROC analyses of subgroups to evaluate the diagnostic usefulness of markers.

Humans↗
PubMed2005

CT screening for lung cancer: update 2005.

Currently available results on CT screening for lung cancer show that (1) the work-up on baseline screening can be confined to less than 15% of the individuals and to less than 6% on annual repeat screening, (2) almost all cases are detected by screening with very few diagnoses made between screening on the prompting of symptoms, and (3) over 80% of all the diagnoses are of stage I. This diagnostic performance results from following the I-ELCAP regimen of screening which defines a positive result of the initial CT in the regimen as well as the work-up leading to a diagnosis of lung cancer. The diagnostic performance raises prognostic questions as to the genuineness and curability of these screen-diagnosed lung cancers. All diagnoses of malignancy were confirmed by an expert pathology review and found to represent genuine lung cancer as defined by the 2004 World Health Organization pathologic criteria. Estimates based on growth rates suggest that about 90% of the baseline-diagnosed stage I cancers are genuine cancers, as are essentially all of those diagnosed on annual repeat screening. Preliminary results of the curability of genuine screen-diagnosed stage I lung cancers indicate a high curability rate of more than 90%. This suggests that more than a high proportion of deaths from lung cancer can be prevented by CT screening followed by early resection. Using these results, the benefit of a single round of CT screening can be determined for an individual based on the age and smoking history.

Cause of Death↗
PubMed2005

An update of CT screening for lung cancer.

Currently available results on CT screening for lung cancer show that 1) the work-up on baseline screening can be confined to less than 15% of the individuals and to less than 6% on annual repeat screening, 2) almost all cases are detected by screening with very few diagnoses made between screening on the prompting of symptoms, and 3) over 80% of all the diagnoses are of Stage I. This diagnostic performance results from following the I-ELCAP regimen of screening which defines a positive result of the initial CT in the regimen as well as the work-up leading to a diagnosis of lung cancer. The diagnostic performance raises prognostic questions as to the genuineness and curability of these screen-diagnosed lung cancers. All diagnoses of malignancy were confirmed by an expert pathology review and found to represent genuine lung cancer as defined by the 2004 World Health Organization pathologic criteria. Estimates based on growth rates suggest that about 90% of the baseline-diagnosed Stage I cancers are genuine cancers as are essentially all of those diagnosed on annual repeat screening. Preliminary results of the curability of genuine screen-diagnosed Stage I lung cancers indicate a high curability rate of more than 90%. This suggests that more than a high proportion of deaths from lung cancer can be prevented by CT screening followed by early resection.

Coronary Artery Disease↗
PubMed1998

Three-dimensional FISP imaging in the evaluation of carotid cavernous fistula: comparison with contrast-enhanced CT and spin-echo MR.

PURPOSE: The purpose of this study was to assess the value of three-dimensional fast imaging with steady-state precession (FISP) MR sequences relative to contrast-enhanced CT and spin-echo MR imaging in the diagnosis of carotid cavernous fistula (CCF). METHODS: Seventeen patients with 19 angiographically proved CCFs had contrast-enhanced CT, spin-echo MR imaging, and 3-D FISP imaging. Three observers assessed these imaging studies as well as those of 43 control sides in a blinded manner for the presence or absence of CCF. Receiver operating characteristic analysis was used to assess the diagnostic utility of each imaging technique. In a nonblinded study, contrast-enhanced 3-D FISP images were also evaluated. RESULTS: Higher diagnostic accuracy was obtained with 3-D FISP sequences, as the shunt flow within the cavernous sinus was well seen. Sensitivity of 3-D FISP images was 83% and specificity was 100% in the blinded study. In the receiver operating characteristic analysis, the diagnostic performance of observers was found to be better with the 3-D FISP images than with the spin-echo MR images. Although there were no significant difference between 3-D FISP and contrast-enhanced CT, higher diagnostic performance was obtained with 3-D FISP images. In three CCFs without anterior drainage, a diagnosis was made only from the 3-D FISP images. The contrast-enhanced 3-D FISP images were not helpful, since the cavernous sinuses enhanced. CONCLUSION: Three-dimensional FISP imaging is superior to spin-echo MR imaging and contrast-enhanced CT in the diagnosis of CCF. Contrast-enhanced 3-D FISP images are not helpful for the evaluation of CCF.

Adolescent↗
PubMed2002

Comparative study of different enzyme immunoassays for measurement of IgM and IgA rheumatoid factors.

OBJECTIVE: To compare the value of various IgM and IgA rheumatoid factor (RF) tests for the diagnosis of rheumatoid arthritis (RA). METHODS: Firstly, the latex test, one global assay (for IgM, IgA, and IgG RF), six IgM, and four IgA RF assays were compared in a particularly challenging situation-that is, with 67 patients with RA, many of whom were latex negative, and 91 non-RA controls, many of whom were latex positive. More detailed evaluation followed with three IgM RF tests (two commercially available kits and one assay developed in our laboratory) and two IgA RF tests (one commercially available and one from our laboratory) in two more representative samples of rheumatological patients (146 RA and 75 non-RA controls). RESULTS: Diagnostic performance differed considerably between the assays. For IgM RF detection the highest sensitivity (88%) was obtained with the Diamedix kit (specificity 67%) and for IgA RF with the Inova kit (sensitivity 65%, specificity 88%). Combining one IgM and one IgA RF test improved diagnostic performance when both tests were in agreement, but at the cost of yielding 15-27% of discrepant results which did not help in ruling RA in or out. Mean concentration values differed significantly among IgM RF tests, and in most cases concentrations were not correlated. CONCLUSIONS: Available tests for IgM RF isotype vary in accuracy, and none is uniformly better than all the others. For IgA RF isotype, the Inova kit appears to be the best. Quantitative results cannot be compared across tests. Combination of one IgM and one IgA RF test may improve diagnostic accuracy.

Adult↗
PubMed2000

The efficacy of hormone assays in the differential diagnosis of amenorrhea and menopause.

The differential diagnosis of menopause and amenorrhea is currently based on the assay of circulating follicle stimulating hormone, luteinising hormone, and estradiol. The diagnostic performance of the three hormone assays, both as single and combined tests, was evaluated considering as reference data the results from 300 subjects for either condition, and assuming menopause-amenorrhea prevalence ratios corresponding to 1 and 10. In the calculation an "allocation" scheme was adopted, and the uncertainty associated with the diagnostic performance parameters was accounted for. The results obtained clearly demonstrate that the addition of a test for luteinising hormone or estradiol (or both) to the testing for follicle stimulating hormone is not justified in terms of improvement of the diagnostic information.

Adolescent↗
PubMed2006

Meta-analysis of diagnostic and screening test accuracy evaluations: methodologic primer.

OBJECTIVE: Interest in evidence-based diagnosis is growing rapidly as diagnostic and screening techniques proliferate. In this article we provide an overview of systematic reviews of diagnostic performance and discuss in detail statistical methods for the most common variant of the problem: meta-analysis of studies in which a pair of estimates of sensitivity and specificity is reported. The need to account for possible variations in threshold for test positivity across studies led to the formulation of the Summary ROC (SROC) curve method. We discuss graphical and model-based ways to estimate, summarize, and compare SROC curves, and we present an example from a meta-analysis of data on techniques for staging cervical cancer. We also present a brief survey of the methodologic literature for addressing heterogeneity, correlated data, multiple thresholds per study, and systematic reviews of ROC studies. We conclude with a discussion of the significant methodologic challenges that continue to face investigators in this area of diagnostic medicine research. CONCLUSION: Systematic reviews of diagnostic performance are a rigorous approach to examining and synthesizing evidence in the evaluation of diagnostic and screening tests. The information from such reviews is needed by clinicians, health policy makers, researchers in diagnostic medicine, developers of diagnostic techniques, and the general public. However, despite progress in study quality and reporting and in methodologic development, major challenges confront investigators undertaking these reviews.

Diagnostic Techniques and Procedures↗
PubMed1998

Diagnostic value of sural nerve biopsy in chronic inflammatory demyelinating polyneuropathy.

OBJECTIVE: To investigate the additional diagnostic value of sural nerve biopsy of 64 patients in whom chronic inflammatory demyelinating polyneuropathy (CIDP) was considered, as sural nerve biopsy is recommended in the research criteria of an ad hoc subcommittee to diagnose CIDP. METHODS: Firstly, the additional diagnostic value of sural nerve biopsy was analysed with multivariate logistic regression. Six clinical features (remitting course, symmetric sensorimotor neuropathy in arms and legs, areflexia, raised CSF protein concentration, nerve conduction studies consistent with demyelination, and absence of comorbidity or relevant laboratory abnormalities) were entered into a logistic model. Afterwards, all significant features identified from this model, as well as the results of sural nerve biopsy were forced into a second logistic model. Secondly, the diagnostic performance of a neurologist experienced in diagnosis of peripheral nerve disorders was studied by receiver operating characteristics (ROC) curve analysis. RESULTS: The results of the first logistic analysis showed that CSF protein concentration >1 g/l (odds ratio (OR)=38.5) and neurophysiological studies consistent with demyelination (OR=51.7) were strong predictors of CIDP. When forcing the significant features and the sural nerve biopsy data into the model, an independent predictive value of sural nerve biopsy could not be found. The neurologist was able to discriminate patients with and without CIDP (area under the curve (AUC)=0.95). His diagnostic performance did not improve significantly by offering him the results of sural nerve biopsy. CONCLUSION: Any additional diagnostic value of sural nerve biopsy in the diagnosis of CIDP could not be shown.

Adolescent↗
PubMed2002

Microalbumin measurement alone or calculation of the albumin/creatinine ratio for the screening of hypertension patients?

BACKGROUND: Spot urine sampling seems to be a reliable screening method for the detection of microalbuminuria in hypertensive patients. It remains unclear whether microalbumin measurement alone or calculation of the albumin/creatinine ratio (ACR) are more reliable for the detection of microalbuminuria in non-selected hypertensive patients. METHODS: Following collection of a spot, midstream urine sample, urine was collected for 24 h for the measurement of microalbumin in 264 hypertensive patients. We compared microalbumin concentration in the spot urine with microalbumin measured in the 24-h urine sample and examined the utility of the ACR in evaluating microalbuminuria in hypertensive patients. Pathologic microalbuminuria was assumed when the microalbumin concentration exceeded 30 mg/l in the 24-h urine sample. Diagnostic performance is expressed in terms of specificity, sensitivity, positive (PPV) and negative predictive value (NPV), and area under receiver operating characteristics curve (AUC). RESULTS: A total of 47 samples (17.8%) showed pathologic microalbuminuria in the 24-h urine sample. The diagnostic performance expressed as AUC was 0.94 (95% CI 0.90-0.98) for microalbumin measurement alone and 0.94 (95% CI 0.89-0.97) for ACR. The PPV and NPV were 44.2 and 97.9% for microalbumin measurement alone. ACR revealed a PPV of 29.3% and a NPV of 96.2% for males and 42.9 and 98% for females, if a cut-off value of 2.5 mg/mmol for males and of 4.0 mg/mmol for females was used. CONCLUSIONS: The ACR did not provide any advantage compared with microalbumin measurement alone, but requires an additional determination of creatinine and the use of gender-specific cut-off values. Therefore, measurement of microalbuminuria alone in the spot urine sample is more convenient in daily clinical practice and should be used as the screening method for hypertensive patients.

Adult↗