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At least 1,711 records · Page 95Linked to original sources
PubMed1998

Localized fibrous tumours of the pleura: 15 new cases and review of the literature.

OBJECTIVE: To present a series of localized fibrous tumours of the pleura (LFTP), to define the clinical and histopathological diagnostic criteria of this tumour, and to determine the optimal treatment and follow-up. METHODS: Review of the charts of the patients with the diagnosis of LFTP (formerly called benign fibrous mesothelioma), as well as of all the histological sections, including immunohistochemical stains. Review of the literature with special emphasis on the clinical and histological criteria of malignancy. RESULTS: During the last 30 years, we found 15 patients with a complete clinical chart and histological material, particularly paraffin blocks of the tumour. The mean age was 57 years (range 27-79). Eight patients were asymptomatic, and the remaining seven presented with non-specific symptoms. All but one had complete resection of the tumour, including partial lung resection in two and partial chest wall resection in three. The diagnosis was confirmed by histological review in 15 cases. Immunohistochemical stainings showed positivity for vimentin in all cases, for CD 34 in 80%, but were consistently negative for cytokeratins. Nine tumours were histologically classified as malignant. Among them, five recurred, two of which were responsible for death. One benign tumour recurred after 1 year, and was treated successfully by repeat resection and radiotherapy. Overall, 13 patients (86%) were alive with no evidence of disease between 10 months and 27 years after the first resection. CONCLUSIONS: LFTP is a rare tumour which has a benign clinical course in over 80% of the cases, and is asymptomatic in half the patients. The diagnosis is difficult to establish before operation. Treatment consists of complete resection including adjacent structures if necessary. The clinical behaviour of LFTP cannot be predicted on the basis of histological aspects only. If histologically malignant tumours are more prone to recurrence and poor outcome, broad-based and locally invasive tumours bear a higher risk of recurrence. Long term follow-up is therefore mandatory in all cases in order to perform early re-resection when recurrence occurs.

Female↗
PubMed2005

Understanding B-type natriuretic peptide and its role in diagnosing and monitoring congestive heart failure.

Congestive heart failure (CHF) is a complex clinical syndrome characterized by dysfunction of the left, right, or both ventricles, which results in the impairment of the heart's ability to circulate blood at a rate sufficient to maintain the metabolic needs of peripheral tissues and various organs. Owing to the drastic increase in cardiovascular risk factors such as obesity, diabetes, and improved survival rate after acute myocardial infarction and subsequent development of CHF in the last quarter of a century, CHF has become a major and increasing cause of death and disability in the United States. Unfortunately, the signs and symptoms are nonspecific for CHF Also, routine laboratory values, electrocardiograms, and X-rays are not always accurate enough to make the appropriate diagnosis. Recently, the US Food and Drug Administration approved a new biomarker, B-type natriuretic peptide (BNP), for the purpose of diagnosing and assessing severity of CHE BNP is synthesized, stored, and released primarily by the ventricular myocardium in response to volume expansion and pressure overload. The use of SNP, along with other diagnostic tools, can enable care providers to facilitate and optimize care of heart failure patients in a variety of clinical settings. Emerging clinical data will help further refine biomarker-guided therapeutic and monitoring strategies involving BNP.

Acute Disease↗
PubMed1994

Oligonucleotide probe design--a new approach.

The use of oligonucleotides for gene amplification, as diagnostic probes or antisense-based drugs can be optimized by minimizing the possibility of nonspecific hybridization.

Base Sequence↗
PubMed2004

Moving towards individualized medicine with pharmacogenomics.

Individuals respond differently to drugs and sometimes the effects are unpredictable. Differences in DNA that alter the expression or function of proteins that are targeted by drugs can contribute significantly to variation in the responses of individuals. Many of the genes examined in early studies were linked to highly penetrant, single-gene traits, but future advances hinge on the more difficult challenge of elucidating multi-gene determinants of drug response. This intersection of genomics and medicine has the potential to yield a new set of molecular diagnostic tools that can be used to individualize and optimize drug therapy.

Drug Design↗
PubMed2000

Using the free-to-total prostate-specific antigen ratio to detect prostate cancer in men with nonspecific elevations of prostate-specific antigen levels.

BACKGROUND: Prostate-specific antigen (PSA) levels between 4.0 to 10.0 ng/ml have poor specificity in prostate cancer screening, leading to unnecessary biopsies. OBJECTIVE: To determine whether the free-to-total PSA ratio (F/T PSA) improved the diagnostic accuracy of these nonspecific PSA levels. MEASUREMENTS AND MAIN RESULTS: MEDLINE searchedwas from 1986 to 1997. Additional studies were identified from article bibliographies and by searching urology journals. Two investigators independently identified English-language studies providing F/T PSA ratio test-operating characteristics data on > or = 10 cancer patients with PSA values between 2.0 and 10.0 ng/ml. Twenty-one of 90 retrieved studies met selection criteria. Two investigators independently extracted data on methodology and diagnostic performance. Investigator-selected cut points for the optimal F/T PSA ratio had a median likelihood ratio of 1.76 (interquartile range, 1.40 to 2.11) for a positive test and 0.27 (0.20 to 0.40) for a negative test. Assuming a 25% pretest probability of cancer, the posttest probabilities were 37% following a positive test and 8% following a negative test. The summary receiver operating characteristic curve showed that maintaining test sensitivity above 90% was associated with false positive rates of 60% to 90%. Methodologic problems limited the validity and generalizability of the literature. CONCLUSIONS: A negative test reduced the posttest probability of cancer to approximately 10%. However, patients may find that this probability is not low enough to avoid undergoing prostate biopsy. The optimal F/T PSA ratio cut point and precise estimates for test specificity still need to be determined.

Data Interpretation, Statistical↗
PubMed2001

[Histology and tumor biology of microinvasive cervix carcinoma].

Microinvasive squamous cell carcinomas account for up to 21% of cervical carcinomas. In this early tumor stage characterized by a maximum depth of 5 mm and a horizontal growth up to 7 mm even an increase in tumor size of only a few millimeters leads to a worse prognosis. Therefore a morphology-based therapy is needed that requires additional prognostically relevant markers. Depth of invasion and capillary-lymphatic space invasion are the most important prognostic parameters. Detection of invasion-associated proteases might be helpful in searching for additional diagnostic and prognostic markers which are necessary for an optimal staging-related therapy. In future studies specific concerns must be addressed to microinvasive adenocarcinomas to ensure a correct staging and an optimal therapy.

Adenocarcinoma↗
PubMed1997

[The effect of a lower stimulation frequency on the AV synchronicity of VDD pacemakers].

BACKGROUND AND OBJECTIVE: Implantation of a VDD pacemaker (ventricular pacing; dual sensing [atrial and ventricular]; dual response [triggered + inhibited]) together with a single VDD electrode catheter restores synchronous AV ventricular stimulation in patients with higher-grade AV block and intact sinus function. If higher-frequency stimulation occurs it may be a sign of pacemaker malfunction or of inadequate pacemaker programming. This study was undertaken to determine, at first follow-up examination, in how many patients with a VDD pacemaker VVI stimulation occurred more than 5% of the time; how such patients differed from those with 5% or fewer VVI stimulations; and whether a changed program reduced the proportion of VVI stimulations. PATIENTS AND METHODS: 67 consecutive patients were tested 1 to 3 months after implantation of the Unity VDD pacemaker (Sulzer Intermedics). The frequency of VVI stimulations was determined via a diagnostic pacemaker memory store. After intermediate analysis, programming was optimized and the patients then re-tested 12 months after the initial implantation. RESULTS: At the first follow-up examination 54 patients had VVI stimulations of < or = 5% (0.5 +/- 0.9%) and 13 had > 5% of the time (19.8 +/- 10.7%). The two groups differed significantly from one another in their lower intervention frequency (< or = 5% VVI stimulations: 47 +/- 6/min; > 5% VVI stimulations: 58 +/- 5/min). In particular, the pacemakers in patients with > 5% VVI stimulations had been significantly more often programmed to values of > 50/min. As a result, the pacemakers of these patients were reprogrammed to a lower frequency. A year after implantation there was no longer any difference in the lower intervention frequency, 44 +/- 4/min, between patients with initially > 5% VVI stimulations and those with initially < or = 5% stimulations. At the same time, the proportion of VVI stimulations fell to 4 +/- 6%, with 67% of patients having AV synchronicity of > 95%. INTERPRETATION: At first follow-up, patients with > 5% VVI stimulations differed from those with < or = 5% stimulations with regard to an increased lower intervention frequency. In most of these patients the proportion of AV stimulations was increased to > 95% by reducing the lower intervention frequency to < or = 50/min.

Aged↗
PubMed1999

Assessment of ambiguous coronary lesions by intravascular ultrasound.

Until recently, coronary angiography has been regarded as the 'gold standard' for visualizing and quantifying coronary artery disease. Coronary angiography, however, is a luminographic technique revealing only the inner lumen of the coronary artery. In contrast, intravascular ultrasound investigations yield a detailed morphological description of the vessel wall and plaque characteristics. Based on these analyses, new insights into the pathogenesis of atherosclerotic coronary disease have evolved, including the remodeling phenomena. Thus, nowadays intravascular ultrasound can be regarded as the new 'gold standard' for the morphological assessment of lesion severity during cardiac catheterizations. Likewise, intracoronary Doppler and intracoronary pressure measurements have demonstrated their superiority in the functional assessment of coronary stenoses. Intravascular ultrasound investigations can be performed with high success and low complication rates. The present manuscript concentrates on the value of IVUS for the assessment of ambiguous lesions. Several forms of ambiguous lesions based on the angiographic appearance, i.e. intermediate lesion with undetermined stenosis severity, aneurysmatic widening of the coronary segment, ostial lesions, branching vessels, vessel tortuosity, main stem lesions, focal spasm, sites of plaque rupture, dissections, unclear haziness and contrast density changes are discussed and illustrated by respective angiographic and IVUS examples. Both the advantages and the limitations of angiographic and intravascular ultrasound examination are discussed in detail. In conclusion, additional intravascular ultrasound examination helps to diagnose accurately the underlying atherosclerotic disease, to define lesion characteristics and to optimize individual patient care and cost with respect to diagnostic catheterizations and coronary interventions.

Journal Article↗
PubMed2005

A brief case-finding questionnaire for common mental disorders: the CMDQ.

OBJECTIVES: The aim of the study was to validate a new case-finding instrument for common mental disorders (CMDQ). METHODS: A cross-sectional, stratified, two-phase study was carried out in 28 general practices in Aarhus County, Denmark. 1785 consecutive patients, 18-65 years old, consulting 38 GPs with a new health problem participated. Patients were screened before consultation using a one-page screening questionnaire including subscales for somatisation (SCL-SOM and Whiteley-7), anxiety (SCL-ANX4), depression (SCL-DEP6) and alcohol abuse (CAGE). A stratified subsample of 701 patients was interviewed using the Schedules for Clinical Assessment in Neuropsychiatry (SCAN) interview. We tested the external validity of the scales using the SCAN interview as gold standard. All data were analysed using appropriate weighted procedures to control for the two-phase sampling design and non-response bias. RESULTS: Estimates of sensitivity and specificity for relevant ICD-10 diagnoses at theoretical optimal cut-off points on subscales: Depressive disorder: 78/86 (SCL-DEP6); Alcohol abuse or dependence: 78/97 (CAGE); Severe anxiety disorder: 77/85 (SCL-ANX4); Somatisation disorder: 83/56 (SCL-SOM); and 75/52 (Whiteley-7); any mental disorder: 72/72 (SCL-8). At the theoretical optimal cut-off points the CMDQ demonstrated higher diagnostic accuracy than GPs on any diagnosis evaluated. CONCLUSION: The study results suggest that the CMDQ has excellent external validity for use as a diagnostic aid in primary care settings.

Adolescent↗
PubMed1999

The misdiagnosis of epilepsy and the management of refractory epilepsy in a specialist clinic.

We assessed the frequency, causes and consequences of erroneous diagnosis of epilepsy, and the outcome of patients referred with 'refractory epilepsy', by retrospective analysis of the case records of 324 patients. The sample was divided into those exposed to anti-epileptic drugs (n = 184), of whom 92 were said to have refractory seizures, and those who had not received treatment (n = 140). The latter group is reported elsewhere. The overall misdiagnosis rate was 26.1% (46/184), with incomplete history-taking and misinterpretation of the EEG equally responsible. Side-effects were reported by 19/40, while unnecessary driving restrictions and employment difficulties were encountered by 12/33 and 5/33, respectively. Of those labelled 'refractory epilepsy', 12 did not have epilepsy. Sixteen were rendered seizure-free and 25 significantly improved by the optimal use of anti-epileptic drugs or surgery. Diagnostic and management services for patients with suspected and established epilepsy are suboptimal, with psychological and socio-economic consequences for individual patients. The resulting economic burden on the health and welfare services is probably substantial.

Ambulatory Care↗
PubMed1980

Assessment of the AUTOGRP patient classification system.

This study was conducted to assess the adaptability of the AUTOGRP Patient Classification System (APCS) to the patient population of western Pennsylvania. The APCS consists of a fixed sex of 383 patient categories, each of which is purported to contain similar patients with respect to resource consumption as measured by length of stay. The assessment of the APCS examines both the reproducibility of the classification using western Pennsylvania patient date and the homogeneity of the resultant categories. The results indicate that the APCS categories examined were not statistically optimal using western Pennsylvania data, and that individual diagnostic-related groups within the APCS do not contain similar patients with respect to resource consumption and with respect to other patient and hospital characteristics.

Computers↗
PubMed2001

The additive value of gated SPET myocardial perfusion imaging in patients with known and suspected coronary artery disease.

In myocardial perfusion scintigraphy, the clinical significance of fixed defects presents some difficulty. In this study, we evaluated whether additional information on left ventricular function assessed by quantitative gated single-photon emission computed tomography (gated SPET) would increase the diagnostic yield of the study in such patients. We studied 55 patients with a previous myocardial infarction and 20 patients without a previous myocardial infarction using gated SPET 99Tc(m)-tetrofosmin myocardial perfusion imaging. Each patient had to have a persistent perfusion defect consisting of at least three contiguous segments in the same vascular territory. The left ventricle was divided into 20 segments which were analysed for perfusion and wall thickening on a 4-point severity scale. Of the 55 patients with myocardial infarction, 19 (35%) patients showed preserved wall thickening in the region of the previous infarction with fixed perfusion abnormalities, which suggested residual myocardial viability. In the 20 patients without myocardial infarction, preserved wall thickening was seen in 10 (50%) patients with fixed perfusion defects, suggesting an attenuation artefact. Conversely, in 16 (29%) patients in the myocardial infarction group and two (10%) patients in the non-myocardial infarction group normal perfusion was associated with severely diminished wall thickening possibly due to stunning. We found an excellent correlation between wall thickening and left ventricular ejection fraction both for the patients with myocardial infarction and the patients without myocardial infarction (r = 0.86 and r = 0.82, respectively, both P<0.0001). A reasonable correlation between perfusion and left ventricular ejection fraction was found for the patients with myocardial infarction (r = 0.41, P = 0.002), and a non-significant correlation for the patients without myocardial infarction (r = 0.37, P = 0.1). Quantitative gated SPET myocardial imaging allows the detection of residual wall thickening in patients with a previous myocardial infarction who show severe fixed perfusion defects. In patients without myocardial infarction, gated SPET imaging allows differentiation between an attenuation artefact and a fixed perfusion defect due to coronary artery disease. In addition, gated SPET may show diminished ventricular function in normally perfused segments possibly due to myocardial stunning. The addition of gated SPET myocardial perfusion imaging increases diagnostic confidence and may have direct clinical implications for optimal patient management.

Aged↗
PubMed2005

Acute low back pain: diagnostic and therapeutic practices reported by Brazilian rheumatologists.

STUDY DESIGN: A cross-sectional study. OBJECTIVES: To assess resource utilization in the diagnosis, management, and hospitalization of patients with low back pain (LBP) as prescribed by Brazilian rheumatologists. SUMMARY OF BACKGROUND DATA: LBP is an important cause of disability, suffering, and social costs. Two to five percent of patients miss workdays because of LBP; it is the second highest cause of physician visits and absenteeism. METHODS: Rheumatologists taking part in a national rheumatology medical congress answered a questionnaire to assess management of patients with LBP. It consisted of two hypothetical scenarios describing patients with acute LBP (scenario 1) and sciatica (scenario 2). There were 29 questions mainly related to education, protective measures, rest, and medication. RESULTS: A total of 207 questionnaires were returned. In scenario 1, 70% of the participants ordered some diagnostic test at first visit; lumbar radiograph was the most ordered (92%), while more than 80% prescribed rest and 100% at least one drug. Nonsteroidal anti-inflammatory drugs were prescribed by 69% of the participants. In scenario 2, 93% of the physicians ordered diagnostic tests at first visit, with computed tomography being the most ordered test (69%). Rest was prescribed by 90% (average 18 days) of the participants and physical therapy was counseled by 84%. CONCLUSIONS: Considering the hypothetical scenarios, participants overused diagnostic and therapeutic procedures. A dissemination of guidelines for optimizing resource use in LBP diagnosis and management is needed.

Acute Disease↗
PubMed2004

Role of polymerase chain reaction and liver biopsy in the evaluation of patients with asymptomatic transaminitis: implications in diagnostic approach.

BACKGROUND AND AIM: Detection of an asymptomatic rise in the hepatic aminotransferase (ARHA) value has become a distinct and frequent clinical problem. We evaluated a three-step diagnostic algorithm in such patients for maximum yield. METHODS: Consecutive patients with an ARHA value 1.5-fold the upper limit of normal for at least 4 weeks and who were apparently healthy were included in the study. Each patient underwent standard biochemical investigations and a stepwise investigative protocol. In the first step, serological markers for hepatitis viruses, serum ferritin, 24-h urinary copper, alpha-1-antitrypsin phenotyping, and autoimmune markers were carried out. In step two, patients who tested negative for all the above markers had polymerase chain reaction (PCR) analysis for hepatitis B virus (HBV)-DNA and hepatitis C virus (HCV)-RNA. Patients without a diagnosis despite the above investigations underwent a liver biopsy as part of step three. RESULTS: Of 105 patients with ARHA, 38 were excluded for various reasons and 67 were included for the final analysis. The mean age was 35.11 +/- 11.96 years and 56 patients were men. The mean body mass index was 24.17 +/- 3.2 kg/m(2). The stepwise diagnostic algorithm achieved a diagnosis in 65/67 (97%) patients. Non-alcoholic steatohepatitis (NASH) and chronic viral hepatitis were the most common diagnoses, in 24 (36%) patients each. Using the diagnostic algorithm a diagnosis was reached in 34% of patients with only serological and biochemical investigations, whereas PCR for HBV and HCV could further detect the presence of active HBV or HCV viremia in 21% (14/97) and a liver biopsy was necessary to establish the diagnosis in 28/67 (42%) patients. CONCLUSIONS: A stepwise diagnostic algorithm in patients with ARHA resulted in an optimal use of PCR and invasive tests such as liver biopsy. Cryptic HBV and HCV infection was frequent among these patients and PCR was necessary in such cases. NASH and chronic viral hepatitis were the most frequent causes of ARHA.

Adolescent↗
PubMed1993

Pitfalls in the echo-Doppler diagnosis of prosthetic valve disorders.

Assessment of artificial heart valves is a classic example of pitfalls in Doppler and color flow echocardiography. These limitations should be analyzed in the context of the most common clinical conditions associated with prosthetic valve dysfunction, that is, assessment of stenosis, regurgitation, endocarditis, and source of emboli. Estimation of the mean transvalvular gradient in addition to valve areas may avoid potential problems of over- or underestimation of stenotic lesions. The combination of acoustic attenuation, acoustic shadowing, and jet(s) eccentricity makes accurate grading of prosthetic regurgitation difficult and often frustrating. Reverberations and side lobe are frequent artifacts that decrease the ability of two-dimensional echocardiography to identify endocarditis-induced lesions such as vegetations and abscesses, as well as potential sources of emboli such as thrombus and atrial septal abnormalities. Transesophageal echocardiography has provided a new window in the evaluation of prosthetic cardiac valve function. With this approach, high frequency, high resolution transducers greatly improve the quality of ultrasound and color flow Doppler images that result in a higher diagnostic yield. In patients with suspected mitral prosthesis malfunction, transesophageal echocardiography is the method of choice. Contrast study during the transesophageal examination increases the sensitivity to detect potential sources of emboli such as patent foramen ovale. The improvement in diagnostic accuracy may allow one to avoid further diagnostic tests and, in selected patients, it may facilitate optimal timing of a surgical intervention.

Echocardiography, Doppler↗
PubMed2005

Quality of reporting of diagnostic accuracy studies.

PURPOSE: To evaluate quality of reporting in diagnostic accuracy articles published in 2000 in journals with impact factor of at least 4 by using items of Standards for Reporting of Diagnostic Accuracy (STARD) statement published later in 2003. MATERIALS AND METHODS: English-language articles on primary diagnostic accuracy studies in 2000 were identified with validated search strategy in MEDLINE. Articles published in journals with impact factor of 4 or higher that regularly publish articles on diagnostic accuracy were selected. Two independent reviewers evaluated quality of reporting by using STARD statement, which consists of 25 items and encourages use of a flow diagram. Total STARD score for each article was calculated by summing number of reported items. Subgroup analyses were performed for study design (case-control or cohort study) by using Student t tests for continuous outcomes and chi(2) tests for dichotomous outcomes. RESULTS: Included were 124 articles published in 2000 in 12 journals: 33 case-control and 91 cohort studies. Only 41% of articles (51 of 124) reported on more than 50% of STARD items, while no articles reported on more than 80%. A flow chart was presented in two articles. Assessment of reporting on individual items of STARD statement revealed wide variation, with some items described in 11% of articles and others in 92%. Mean STARD score (0-25 points available) was 11.9 (range, 3.5-19.5). Mean difference in STARD score between cohort studies and case-control studies was 1.53 (95% confidence interval: 0.24, 2.82). CONCLUSION: Quality of reporting in diagnostic accuracy articles published in 2000 is less than optimal, even in journals with high impact factor. Authors, editors, and reviewers should pay more attention to reporting by checking STARD statement items and including a flow diagram to represent study design and patient flow.

Case-Control Studies↗
PubMed1986

Interaction sleep and epilepsy.

In order to improve the diagnosis of epilepsy, a routine EEG recording can be supplemented with a long-lasting sleep recording or with an ambulatory EEG recording. In this paper we compare the all-night polygraphic sleep recording with the 3- to 5-hour recording after 1 night total sleep deprivation, and we discuss the outcome with each. In the first part we have analyzed the relationship between the clinical form of epilepsy and the kind and depth of sleep and we have tried to determine the optimal registration time (in hours) to obtain a maximum diagnostic gain. In the second part we have evaluated the changes in the sleep composition induced by the occurrence of epileptic EEG phenomena and by the intake of antiepileptic drugs. In the third part we have analyzed the changes in the morphological aspects of the epileptic EEG phenomena which can occur under influence of light (NREM 1-2) and deep (NREM 3-4) slow-wave sleep and REM sleep. A sufficient knowledge of these changes is very important to avoid misinterpretations.

Electroencephalography↗
PubMed1986

The myocardial signature: absolute backscatter, cyclical variation, frequency variation, and statistics.

This paper studies the absolute myocardial backscatter as a function of the frequency and phase of the cardiac cycle. This was achieved by calibration of the ultrasonic instrumentation and the random diffraction process. We have discovered a first-order model in which the scattering from the myocardium is Rayleigh scattering with a cardiac cycle variation in the scattering cross section. Furthermore, the statistics are approximately those of a radio frequency waveform with two independent Gaussian components (Rayleigh envelope). Deviations from the first-order model suggest measurable fine structure related to myocardial ultrastructure. This model has profound effects on the choice of optimal radiation patterns and signal processing schemes for preparing diagnostic parameters (e.g., integrated backscatter).

Animals↗