Diagnostic accuracy of clinical symptoms in obstructive airway diseases varied within different health care sectors.

OBJECTIVE: To determine the diagnostic accuracy and diagnostic patterns of clinical symptoms in patients suspected to suffer from obstructive airway diseases (OADs) within different health care sectors. STUDY DESIGN AND SETTING: Ten general practices (219 patients), one practice of pneumologists (259 patients) and one specialist hospital (300 patients). Sensitivities, specificities, positive (LR+), and negative (LR-) likelihood ratios of clinical symptoms were compared with lung function testing. RESULTS: Thirty-one percent had chronic obstructive pulmonary disease (COPD), 21% had asthma. Sensitivities increased and specificities decreased from outpatient to hospital setting. The multivariate model of adjusted likelihood ratios for COPD showed LR+=4.86 (95% confidence interval [CI]=2.09-11.29) and LR-=0.07 (95% CI=0.01-0.43) of the combination "wheezing," "dyspnea when going upstairs," "smoking" in general practice. In hospital, the combination "dyspnea when going upstairs," "dyspnea during minimal exercise," and "smoking" showed LR+=3.34 (95% CI=2.08-5.31) and LR-=0.02 (95% CI=0.01-0.12). The combination "no coughing," "dyspnea attacks," and "no smoking" showed LR+=4.08 (95% CI=1.67-10.4) and LR-=0.24 (95% CI=0.12-0.58) for asthma in general practice. The combination "dyspnea attacks" and "no dyspnea when walking" showed LR+=6.48 (95% CI=1.01-40.94) and LR-=0.28 (95% CI=0.11-0.75) for asthma in hospital. CONCLUSION: Clinical decision rules for OAD need to be derived from original studies in their respective settings or assessed on their transferability to other settings.

Techniques for the detection of coronary atherosclerosis: multi-detector row CT coronary angiography.

PURPOSE: To investigate the accuracy of different computed tomographic (CT) reformation techniques in assessing the coronary arteries. MATERIALS AND METHODS: Sixty-four patients undergoing both multi-detector row CT and invasive coronary angiography were consecutively included in a retrospective study. CT scans were obtained with collimation of 4 x 1 mm, pitch of 1.5, and rotation time of 500 msec. Retrospective electrocardiographic gating was used for image reconstruction, with 1.25-mm section thickness and 0.5-mm increment. The CT data set of each patient was evaluated by independent observers using transverse scanning, virtual endoscopic, and three-dimensional reformation and multiplanar reformation. RESULTS: Hemodynamically relevant stenoses (>50%) were detected with highest sensitivity at transverse scanning (58 of 79 [73.4%] stenoses), followed by virtual endoscopic (38 of 79 [48.1%] stenoses) and three-dimensional reformation (34 of 79 [43.0%] stenoses), and multiplanar reformation (37 of 79 [46.8%] stenoses). Atherosclerotic plaques were identified with comparable sensitivities at transverse scanning (143 of 218 plaques [65.6%]) and at three-dimensional (139 of 218 [63.8%] plaques) and virtual endoscopic reformation (136 of 218 [62.4%] plaques). Multiplanar reformation had distinctly poorer results (217 of 218 [58.3%] plaques). Combined interpretation with all four techniques increased sensitivity to 74.7% (59 of 79) for stenosis and 71.6% (156 of 218) for atherosclerosis. Calculated overall specificity was 91.4% or greater. Sufficient vascular evaluation was possible only in vessels larger than 1.6 mm in diameter. Thus, even in patients with heart rates below 60 bpm, only 80.0% of all coronary segments could be visualized, while at higher frequencies, visibility decreased to 66.2%. CONCLUSION: Although multi-detector row CT is a favorable alternative procedure in evaluating coronary arteries, its clinical value still is restricted to low heart rates and proximal coronary arterial segments.