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Negative Test (negative + test)
Terms modified by Negative Test Selected AbstractsDiagnostic and Prognostic Use of Stress Echocardiography in Stable PatientsECHOCARDIOGRAPHY, Issue 5 2000Steven C. Smart M.D. Stress echocardiography is an effective diagnostic and prognostic technique in stable patients with known or suspected coronary artery disease (CAD), myocardial infarction, or chronic left ventricular dysfunction and those undergoing noncardiac surgery. Stress echocardiography is sensitive and specific for the detection and extent of CAD. Negative tests confer a high negative predictive value for cardiac events regardless of the clinical risk. Positive studies confer a high positive predictive value for ischemic events in patients with intermediate to high clinical risk. Stress echocardiography provides incremental prognostic information relative to clinical, resting echocardiographic, and angiographic data. Meta-analysis studies have shown that the diagnostic and prognostic information provided by stress echocardiography is comparable to that from radionuclide scintigraphic stress tests. Stress echocardiography may be more specific for the detection and extent of CAD, whereas radionuclide scintigraphy may be more sensitive for one-vessel disease. Sensitivities are similar for the detection and extent of disease in patients with multivessel CAD. [source] HPV triage testing or repeat Pap smear for the management of atypical squamous cells (ASCUS) on Pap smear: is there evidence of process utility?HEALTH ECONOMICS, Issue 5 2008Kirsten Howard Abstract A two-stage standard gamble was used to evaluate women's preferences for alternative managements of atypical squamous cells of undermined significance (ASCUS) on Pap smear (repeat Pap smear compared with immediate HPV test), and to test for the evidence of process utility. Women's utilities for the health state scenarios were clustered towards the upper end of the 0,1 scale with considerable variability in women's preferences. There was evidence of process utility, with immediate human papillomavirus (HPV) testing strategies having lower valuations than repeat Pap smear, where the clinical outcome was the same. Mean (95% CI) utilities for HPV testing (negative test) followed by resolution were 0.9967 (0.9957,0.9978) compared with repeat Pap smear followed by resolution: 0.9972 (0.9964,0.9980). Mean (95% CI) utilities for immediate HPV testing (positive test), followed by colposcopy, biopsy and treatment were 0.9354 (0.8544,1.0) compared with repeat Pap smear followed by colposcopy, biopsy and treatment: 0.9656 (0.9081,1.0). Our results add to the existing evidence that the impact of healthcare interventions on well-being is not limited to the effect of the intervention on the health outcomes expected from the intervention; process of care can have quality of life implications for the individual. A modelled application of trial-based data will allow characterisation of the true population costs, benefits, risks and harms of alternative triage strategies and subsequent policy implications thereof. Copyright © 2007 John Wiley & Sons, Ltd. [source] The Positions of the Patients in the Diagnosis of Patent Foramen Ovale by Transcranial DopplerJOURNAL OF NEUROIMAGING, Issue 4 2003Gregory Telman ABSTRACT Background and Purpose. There is no information about the optimal position of a patient for the performance of a transcranial Doppler (TCD) examination to detect patent foramen ovale (PFO). Such information is important to improving the sensitivity of the test in comparison to the gold standard of transesophageal echocardiography (TEE). Methods. Thirty-four patients with TEE-proved PFO were examined by contrast TCD. Examinations were done in both the sitting and supine positions in random order. Results. Eight hundred ninety-two microemboli were recorded. Patients'positions and the sequence of testing did not affect the number of microemboli detected. Yet for each individual, 1 of the 2 positions was more sensitive. Conclusions. To improve the sensitivity of TCD in the detection of PFO, it is recommended, in the case of a first negative test, to change the patient's position for a repeated TCD examination. [source] Utility of consecutive repeat HIT ELISA testing for heparin-induced thrombocytopeniaAMERICAN JOURNAL OF HEMATOLOGY, Issue 3 2008Maren Chan Heparin-induced thrombocytopenia (HIT) is a serious complication of heparin therapy. Limited data are available regarding repeat HIT antibody testing after an initial negative test. We conducted a retrospective study to determine the utility of repeat testing. Heparin antibodies were detected using the GTI-PF4 enzyme-linked immunoabsorbent assay, ELISA (GTI Diagnostics, Waukesha, WI). Patients (n = 137) were assigned to one of three groups based upon the initial negative test optical density (OD) range of low = 0,0.132, medium = 0.133,0.267, and high = 0.268,0.399. A pretest clinical score was retrospectively determined using the "4T's" (Thrombocytopenia, Timing of platelet fall, Thrombosis, and the absence of oTher causes of thrombocytopenia). A subsequent positive ELISA was found in 16% (22/137) of patients who underwent repeat testing. Most of these patients had a low pretest clinical score (62%). Four patients had an interval change in the pretest score between the initial negative and subsequent positive tests. Only these four patients developed HIT with thrombosis (HITT). Eighty percent of patients with a high initial negative test OD value had a positive ELISA on repeat testing; however, the initial negative test OD value could not predict whether a patient developed HITT. In contrast, an increase in the pretest clinical probability between initial and repeat testing better predicted HITT. Consecutive repeat ELISA testing for heparin antibodies may be warranted in patients with an increase in their pretest clinical score after an initial negative test as an adjunct to confirm the diagnosis of HIT. Am. J. Hematol., 2008. © 2007 Wiley-Liss, Inc. [source] Anti,Heat Shock Protein 70 Antibodies in Meniere's Disease ,THE LARYNGOSCOPE, Issue 9 2000Steven D. Rauch MD Abstract Objectives To determine the prevalence of anti,heat shock protein 70 (anti-HSP70) antibodies in patients with Meniere's disease and healthy subjects and to probe the relationship between antibody status and clinical features of Meniere's disease. Study Design Prospective cohort study of consecutive consenting patients with Meniere's disease. Methods Serum samples were obtained prospectively from 134 patients with Meniere's disease and 124 blood donors. Serial samples were taken at 3-month intervals in 38 of 134 patients with Meniere's disease. Demographic data and clinical characterization of vestibular and auditory status were acquired with each sample. Serum was assayed for anti-HSP70 antibodies by Western blot using bovine renal extract, recombinant bovine HSP70, and recombinant human HSP70 antigens. Results Immunoreactivity against bovine renal extract HSP70 was found in 38% of patients with Meniere's disease, compared with 25% of blood donors (P < .04). Reactivity with recombinant antigens was not significantly different between patients with Meniere's disease and healthy control subjects. Patients with Meniere's disease who reacted with all three antigens were more likely to have simultaneously active hearing and balance symptoms (P = .03). Neither univariate nor multivariate statistical analysis established any other association between serological findings and clinical features of Meniere's disease. Tests performed on serial samples of patients with Meniere's disease also showed no association of positive or negative test results with changes in clinical course. Conclusions Because of the high prevalence of anti-HSP70 antibodies in healthy subjects and the very limited association of anti-HSP70 antibody status with clinical features or course of Meniere's disease, we conclude that, at present, the detection of anti-HSP70 antibodies by Western blotting offers little clinically useful information in Meniere's disease. [source] Emergency Thoracic Ultrasound in the Differentiation of the Etiology of Shortness of Breath (ETUDES): Sonographic B-lines and N-terminal Pro-brain-type Natriuretic Peptide in Diagnosing Congestive Heart FailureACADEMIC EMERGENCY MEDICINE, Issue 3 2009Andrew S. Liteplo MD Abstract Objectives:, Sonographic thoracic B-lines and N-terminal pro-brain-type natriuretic peptide (NT-ProBNP) have been shown to help differentiate between congestive heart failure (CHF) and chronic obstructive pulmonary disease (COPD). The authors hypothesized that ultrasound (US) could be used to predict CHF and that it would provide additional predictive information when combined with NT-ProBNP. They also sought to determine optimal two- and eight-zone scanning protocols when different thresholds for a positive scan were used. Methods:, This was a prospective, observational study of a convenience sample of adult patients presenting to the emergency department (ED) with shortness of breath. Each patient had an eight-zone thoracic US performed by one of five sonographers, and serum NT-ProBNP levels were measured. Chart review by two physicians blinded to the US results served as the criterion standard. The operating characteristics of two- and eight-zone thoracic US alone, compared to, and combined with NT-ProBNP test results for predicting CHF were calculated using both dichotomous and interval likelihood ratios (LRs). Results:, One-hundred patients were enrolled. Six were excluded because of incomplete data. Results of 94 patients were analyzed. A positive eight-zone US, defined as at least two positive zones on each side, had a positive likelihood ratio (LR+) of 3.88 (99% confidence interval [CI] = 1.55 to 9.73) and a negative likelihood ratio (LR,) of 0.5 (95% CI = 0.30 to 0.82), while the NT-ProBNP demonstrated a LR+ of 2.3 (95% CI = 1.41 to 3.76) and LR, of 0.24 (95% CI = 0.09 to 0.66). Using interval LRs for the eight-zone US test alone, the LR for a totally positive test (all eight zones positive) was infinite and for a totally negative test (no zones positive) was 0.22 (95% CI = 0.06 to 0.80). For two-zone US, interval LRs were 4.73 (95% CI = 2.10 to 10.63) when inferior lateral zones were positive bilaterally and 0.3 (95% CI = 0.13 to 0.71) when these were negative. These changed to 8.04 (95% CI = 1.76 to 37.33) and 0.11 (95% CI = 0.02 to 0.69), respectively, when congruent with NT-ProBNP. Conclusions:, Bedside thoracic US for B-lines can be a useful test for diagnosing CHF. Predictive accuracy is greatly improved when studies are totally positive or totally negative. A two-zone protocol performs similarly to an eight-zone protocol. Thoracic US can be used alone or can provide additional predictive power to NT-ProBNP in the immediate evaluation of dyspneic patients presenting to the ED. [source] 1242: Over-reliance on negative test resultsACTA OPHTHALMOLOGICA, Issue 2010V PURVIN Purpose This course focuses on areas of frequent diagnostic confusion in the field of neuro-ophthalmology. Methods The course uses a case-based method. Cases are presented as unknowns, each illustrating the specific clinical feature or features that should point to the correct diagnosis. Results Certain tests may provide misleading information, apparently "ruling out" a particular disorder, when in fact that is the correct diagnosis. Examples include serologic tests for ocular myasthenia, falsely negative temporal artery biopsy for giant cell arteritis and MRI scans in certain some disorders. Conclusion In order to interpret the results of ancillary testing we must know the clinical features of the disease in question and the limitations of the tests we use. [source] Usefulness of skin testing in cutaneous drug eruptions in routine practiceCONTACT DERMATITIS, Issue 3 2009Tatiana Tchen Background: Cutaneous drug eruptions are common side-effects. The imputation score combining intrinsic (chronology, clinical and paraclinical signs) and extrinsic criteria used in Pharmacovigilance Centres is insufficient alone to identify with certainty a responsible drug. Objective: To evaluate the imputation score before and after performing skin testing in patients with cutaneous drug eruptions. Patients/Methods: A single-centre retrospective study was performed on 339 patients tested between 2001,2006. Imputation scores were calculated before and after skin tests for each cutaneous drug eruption according to the clinical type of skin eruption and the type of drug. Results: Among 121 patients meeting inclusion criteria, 46% showed an increase of the imputation score as shown by 25/41 cases of maculo-papular exanthema, 4/11 cases of acute generalized exanthematous pustulosis and 17/41 cases of urticaria/anaphylaxis. The imputation score increased in 25/70 cases of the tested antibiotic drugs, in 14/56 cases of cardiovascular drugs, and it increased in 19 patients (34%) with I1 or I2 imputation scores before skin testing and in 29 (52%) with an I3 imputation score before skin testing. Conclusions: Drug skin testing appeared useful in investigating cutaneous drug eruptions in routine practice, including not only drugs with a high imputation score (I3) but also those with a lower score (I1, I2). Drug skin testing should lead to oral rechallenge of drugs with negative tests in order to determine which drugs may be used safely. [source] Breast lymphoma in Sjögren's syndrome complicated by acute monocular blindnessINTERNATIONAL JOURNAL OF RHEUMATIC DISEASES, Issue 2 2010Helmar F. SOLDEVILLA Abstract A 69-year-old hypertensive woman presented with eye and mouth dryness, bilateral parotid gland enlargement, associated with anasarca and proteinuria. Family history was notable for malignancies including breast, nasopharyngeal and colon cancers. Physical exam disclosed hypertension, bilaterally enlarged, firm, non-tender parotid glands, fine bibasilar crackles and bipedal edema. Anti Ro/Sjögren's syndrome antigen A antibody was positive, with negative tests for anti La/Sjögren's syndrome antigen B and anti-nuclear antibody (ANA). Chest radiographs showed basal infiltrates. Sjögren's syndrome associated with glomerulonephritis and interstitial lung disease was diagnosed, and she received pulse methylprednisololone followed by oral prednisone with dramatic improvement. Two months later, while on prednisone 5 mg/day, she returned to the clinic with an enlarging fixed non-tender right breast mass. She underwent modified radical mastectomy of the right breast, and pathologic report revealed diffuse, small cell, non-Hodgkin's lymphoma of the breast; axillary lymph nodes were negative for tumor. She opted for alternative therapy and did not return to the clinic until 7 months later when she developed sudden monocular blindness in the right eye with no other systemic manifestations. Magnetic resonance imaging (MRI) revealed swelling and enhancement of intracanalicular and pre-chiasmatic segments of the right optic nerve and right side of the optic chiasm. Considerations were Devic's disease versus metastases. She received pulse methylprednisolone therapy (1 g/day for 3 days) with partial recovery of vision. She is scheduled for lymphoma chemotherapy to include rituximab. [source] Non-alcoholic fatty liver syndrome: A hepatic consequence of common metabolic diseasesJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 5 2003FRANCESCO ANGELICO Abstract Background and Aims: The association of liver steatosis with a number of common metabolic conditions has been suggested. The aim of the present study was to evaluate the clinical features of subjects with different severities of steatosis. Methods: The present study was performed in 282 consecutive patients with ,bright liver' at ultrasonography and in 58 subjects without steatosis. They had no history of alcohol abuse and negative tests for the presence of hepatitis B and C virus. Patients underwent clinical examination, anthropometry, laboratory tests and routine liver ultrasonography. Steatosis was graded as absent, mild, moderate and severe. Results: A progressive increase in the prevalence of obesity (P < 0.001), type 2 diabetes (P < 0.001), alanine aminotransferase (ALT) elevation (P < 0.001) and hypertriglyceridemia (P < 0.001), and a decrease of hypercholesterolemia (P < 0.05) was observed from the control group to the groups with mild, moderate and severe steatosis. More than half the subjects with liver steatosis had insulin resistance metabolic syndrome. Obesity, diabetes and hypertriglyceridemia were more common by 5.3-fold, 4.0-fold, and 6.7-fold, respectively, in subjects with severe steatosis, as compared to controls. Prevalence of obesity, diabetes and hyperlipidemia was significantly higher in subjects with fatty liver and ALT elevation. Conclusion: Fatty liver can be considered as the hepatic consequence of common metabolic diseases. © 2003 Blackwell Publishing Asia Pty Ltd [source] Hair Analysis Versus Conventional Methods of Drug Testing in Substance Abusers Seeking Organ TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2010D. L. Haller As substance abusers need to demonstrate abstinence prior to transplant, valid/reliable drug tests are needed. Patients may deny use, fearing surgery will be delayed. Breath, blood and urine tests have brief detection windows that allow patients to evade detection. Routine laboratory tests do not include all substances of abuse. Hair analysis overcomes these barriers, increasing the likelihood that active users will be identified. This study compared results for alcohol, opioids and cocaine based on 445 self-report, breath, urine and hair samples from 42 patients who had been denied a transplant due to recent substance abuse. Compared to hair toxicology, sensitivity for conventional drug tests was moderate for cocaine and opioids, but poor for alcohol. Of positive hair tests, only half were corroborated through other tests. In contrast, specificity was high across tests and substances, with positive findings from conventional tests confirmed through hair toxicology. Based on a 90-day detection window for hair analysis, two negative tests suggest 6 months of continuous abstinence. Hair testing should be considered as an alternative approach for monitoring substance use in the transplant population, either as a routine procedure or when the veracity of findings from conventional tests is in doubt. [source] Long-Term Follow-Up of Patients with Syncope Evaluated by Head-Up Tilt TestANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 2 2010Giulia Domenichini M.D. Background: Clinicians may be tempted to consider a positive head-up tilt test (HUTT) an unfavorable prognostic indicator. We investigated whether results of routine HUTT predict long-term recurrence of syncope. Methods: We analyzed syncope recurrence at long-term among 107 patients (mean age 51 ± 20 years) receiving HUTT for diagnostic evaluation of unexplained/suspected neurocardiogenic syncope in our Institute. Results: HUTT was positive in 76 patients (vasodepressive response, n = 58; cardioinhibitory, n = 5; mixed, n = 13). During a median follow-up of 113 months (range, 7,161), 34 (32%) patients experienced recurrence (24 [32%] with positive HUTT during 110 months (7,159); 10 [32%] with negative HUTT during 120 [22,161] months). Actuarial freedom from recurrence at 10 years did not significantly differ for patients with positive/negative test results (after passive/active phases) or with different positive response patterns (vasodepressive, cardioinhibitory, mixed). By contrast, history of >4 syncopes in the 12 months preceding HUTT stratified risk of recurrence, irrespective of HUTT positivity/negativity. At Cox proportional hazards analysis, history of >4 syncopes in the 12 months preceding HUTT was the single independent risk factor for recurrence both in the overall study population (HR, 1.7; 95% CI, 1.07,2.69) and within the subset of patients who tested positive (HR, 1.83; 95% CI, 1.07,3.17). Conclusions: This long-term follow-up study reinforces the concept that a positive HUTT should not be considered an unfavorable prognostic indicator; frequency of recent occurrences may be a more valid predictor. Ann Noninvasive Electrocardiol 2010;15(2):101,106 [source] | ||||||||||