False Negative

Background Real world cardiology is faced with a low diagnostic yield of coronary angiography (CXA) in patients presenting with ACC/AHA class II CXA indication. Our aim was to analyze the clinical implication of a Cardiac MR (CMR) protocol including adenosine stress perfusion in this patient population. We examined whether CMR could enhance appropriate CXA indication and thus reduce the rate of pure diagnostic CXA. In addition, we compared the relative impact of CMR exam components (perfusion, function and viability assessment) in achieving this target. Methods 176 patients were referred for CXA with class II indication. 171 underwent complete additional CMR exam in a 1.5-T whole body CMR-scanner for myocardial function, ischemia and viability prior to CXA. The routine protocol for assessment of CAD consisted of functional imaging (long and short axes), adenosine stress- and rest-perfusion in short axis orientation and “late enhancement” imaging in long and short axes. Images were analyzed by two independent and blinded investigators. Interobserver differences were resolved by a third reader. Results There was a high association between CMR results and subsequent invasive findings (chi square for CMR perfusion deficit and stenosis >70% in CXA: 113.7, p70%. Four (2.3%) patients had false negative CMR findings. In 58 patients (33.9%) no relevant coronary artery stenosis could be observed, correctly predicted by CMR in 48 cases; in 10 (5.8%) patients CMR provided false positive results. Sensitivity of CMR to detect relevant CAD (>70% luminal narrowing) was 0.96, specificity 0.83, positive predictive value 0.92 and negative predictive value 0.92. Of the CMR components, perfusion deficit was the strongest independent predictor (odds ratio 132.3, p Conclusion In a great number of patients being referred to cath lab with ACC/AHA class II indication for CXA, CMR provides a high accuracy for decision making regarding appropriateness of the invasive exam. CMR prior to CXA could substantially reduce pure diagnostic coronary angiographies in patients with intermediate probability for CAD, in our patient-cohort from approximately 34% to 6%. Further studies are warranted to identify rare false negative CMR results.

The aim of this study was to evaluate the accuracy of a new, continuous real time (13)C-urea breath test, BreathID, for the diagnosis of Helicobacter pylori in patients taking proton pump inhibitors (PPIs). Fifty-two consecutive patients, positive for H. pylori by BreathID, were prospectively evaluated. Patients were randomized to receive either omeprazole 20 mg/day or pantoprazole 40 mg/day for 14 days. A repeat breath test was performed on day 14 while patients received their last PPI pill. Patients were given a test drink containing 75 mg (13)C-urea and 4.0 g citric acid. Real time, continuously sampled expired (13)CO(2), obtained within 6-20 min, was compared with measurement of expired (13)CO(2) by isotope ratio mass spectrometry (IRMS). A full set of test data was available for 43 patients. After 14 days of treatment with PPIs, false negative detection of H. pylori occurred in only 1/43 (2.3%) patients examined by continuous real time (13)C-urea breath test compared with 2/43 ...

The purpose of this study was to evaluate prospectively the sensitivity and specificity of scintimammography in the detection of both primary breast cancer and axillary lymph node involvement. Sixty-five consecutive women referred for a suspicious breast lesion on clinical examination and/or with abnormal mammographies suggestive of malignancies were studied with scintimammography using planar prone imaging (with a chest positioning device with semicircular lateral aperture on the imaging table) performed 15 min postinjection of 25-30 mCi 99mTc-sestamibi. Three planar views, right and left lateral prone and anterior supine thoracic views, were obtained (8-10 min/view). The entire breast and ipsilateral axillary region were included in the field of view. Excisional breast biopsy and/or fine needle aspiration cytology were performed in all patients within 4 wk after scintimammography. Axillary node dissection was also performed. The largest primary tumor measured 2 x 3 cm. There were ...

KEYWORDS Recurrent pregnancy loss; immunity; pro-inflammatory cytokines; homogenous samples ... ABSTRACT It is a well-known fact that pro-inflammatory cytokines exert an adverse effect on conceptus and result in pregnancy failure and there are mutations reported in ...

Abstract The problem of detecting the QRS complex in the presence of noise was analysed. Most QRS detectors contain a filter to improve the signal-to-noise ratio and compare the signal with a threshold. In an earlier paper we identified an optimal filter. Various techniques to generate threshold and detector designs were studied. Automatic gain-control circuits with a fixed threshold have a very slow response to different rhythms. Automatic threshold circuits based on simple peak-detection schemes have a fast response, but are very sensitive to ...

Laboratory diagnosis of feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) usually involves both viruses, as the clinical signs are similar and coinfection may occur. Serological methods may not represent an accurate diagnosis: maternal antibodies or cross-reactions may give false positive results to FIV, and false negative results may occur in latent FeLV status, or in certain FIV infection stages. A nested polymerase chain reaction (PCR) technique was designed to detect FeLV, FIV and feline endogenous retrovirus simultaneously. The detection of endogenous sequences was considered indicative of successful DNA extraction. The technique was used to diagnose FIV and FeLV in the blood cells of 179 cats. The kappa value with the serological data was 0.69 for FeLV and 0.87 for FIV. The joint detection of FeLV and FIV by this novel nested PCR is sensitive, specific, fast and convenient, and its applicability for clinical diagnosis is promising, as the direct evidence of the presence of the virus is more realistic than the indirect data provided by the serological detection.

The aim of this study was to use the Eating Attitudes Test-26 (EAT-26) as a screening instrument on a specific population with a marked prevalence of binge eating disorder (BED) and eating disorder not otherwise specified (EDNOS). The EAT-26 questionnaire was used in order to identify the high-risk subjects for referral to clinical evaluation. EAT-26 was administered to 845 subjects who, for the first time, came to the Nutritional Medicine Service looking for a diet between January 1999 and December 2002. From this initial sample, subsequently, 250 subjects were randomly selected and administered a semistructured clinical interview for DSM-IV (SCID I, version 2.0). Discriminant analysis provided a cutoff value of EAT-26=11. Logistic regression analysis indicated high Dieting (D) or Bulimia (B) subscale scores as a risk factor of EDNOS or bulimia nervosa (BN) cases, respectively; on the other hand, a high Oral Control (O) subscale score represented a protecting factor for BED cases. ...