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At least 289 records · Page 16Linked to original sources
PubMed1989

[Diagnostic methods in aneurysms of the abdominal aorta].

Various diagnostic procedures are currently used for the correct diagnosis of abdominal aortic aneurysms. The different procedures are selected in order to detect the morphology of the lesion (craniocaudal extension), associated steno-obliterative lesions and, on the basis of clinical findings, presence of possible aneurysmatic ruptures. In this paper the limits and advantages of different diagnostic procedures are compared and the use of these various techniques discussed.

Angiography↗
PubMedDate not supplied

[Celiac disease: correlation of different diagnostic methods (author's transl)].

The results of four diagnostic tests have been critically evaluated (xylosemia, serum Ig A level, steatorrhea, X-Ray of the digestic tract) in 80 cases of atrophy of the small intestinal mucosa discovered by biopsy, and in 20 cases in which the biopsy has proved normal. In the celiac subjects the best correlation with the biopsy was found with xylosemia (90%), followed by serum Ig A (87%), by X-Ray of the digestive tract (86%) and finally by steatorrhea (59%). Even in cases without histological alteration of the mucosa, and xylosemia proved abnormal in 70% of the cases, the seric IgA resulted higher greater than 2 delta in 35%, the steatorrhea in 29% while the X-Ray of the digestive tract has never given a false diagnosis. The presence of false negative or positive results in all four tests (except the radiological tests) reconfirms the absolute necessity for biopsy of the digestive tract in the diagnosis of celiac disorder, and has led the AA. Carry out whenever possible the xylosemia, the steatorrhea and the serum IgA level because in none of the 80 cases of celiac disorder has there been a false negative result in all three such tests at the same time.

Celiac Disease↗
PubMed1997

Regulatory issues unique to clinical trials on periodontal diagnostic methods and devices.

A wide variety of in vitro diagnostic products have been proposed for use in patients with periodontal disease. The Food and Drug Administration (FDA) review focuses on three important issues. First, the product must exhibit acceptable analytical performance (accuracy, precision, analytical sensitivity, and analytical specificity). Second, the effectiveness of the device must be clearly defined. The studies required to establish this will depend largely on the proposed intended use of the product. At a minimum, clinical or diagnostic sensitivity and specificity should be established. Finally, the product must meet the labeling requirements for in vitro devices. These requirements outlined in CFR 809.10(b) are comprehensive and cover 15 key elements including information about the principles of the analytical method; handling of instruments, reagents, and patient samples; test limitations; and test performance. Applicants developing products for any in vitro diagnostic device are encouraged to review the labeling regulations along with other divisional and office guidance material to help in defining the submission requirements. The FDA is willing to meet and work with companies prior to and during preclinical and clinical trials to assist in the development of appropriate study protocols.

Clinical Trials as Topic↗
PubMed1999

Efficacy of PCR and other diagnostic methods for the detection of respiratory adenoviral infections.

Five methods were evaluated for the detection of adenovirus directly from nasopharyngeal aspirates (NPA), including conventional and rapid virus culture, two antigen detection tests, and the polymerase chain reaction (PCR). NPA specimens were obtained from 269 military conscripts suffering from an acute respiratory infection during an adenovirus outbreak. In 133 cases, paired blood specimens were also available. Virus culture followed by a hexon-specific immunofluorescence revealed 159 (59%) adenovirus-positive specimens and it was used as a reference method. In comparison to conventional culture, a rapid 2-day culture method had a sensitivity of 71%. The sensitivities of an enzyme immunoassay and time-resolved fluoroimmunoassay were 53% and 46%, respectively. The PCR method employing Ad7 hexon-specific primers showed a high sensitivity of 94%, and revealed an additional 15 (6%) specimens that could not be confirmed by virus culture. Serology based on significant adenovirus antibody rises had a diagnostic efficacy nearly equal to the virus culture and PCR methods, but a relatively high number of discordant results was found. The present study demonstrates that PCR is a very sensitive rapid diagnostic method for detecting adenovirus specific DNA in NPA specimens of adults.

Adenovirus Infections, Human↗
PubMed1989

[Psychological aspects of diagnostic methods in pregnancy].

Psychological effects and sequelae of prenatal diagnostics are presented using material of clinical trials and the results of client-centered counselling. All methods (ultrasound, alpha-fetoproteinscreening, amniocentesis and chorionic villous sampling) can only be understood with their effects upon mother - fetal bonding. A decision process, invasivity and discussion about a fetal malformation are the main characteristics of amniocentesis. High-risk populations like women with complicated pregnancies or advanced age profit most by prenatal diagnosis. The reactions and emotions of male partners are also discussed. The following guidelines for counselling are proposed: non-directive counselling dealing with facts and emotions, patient autonomy and preparation routines apt to reduce anxiety.

Adaptation, Psychological↗
PubMed1999

A review of the diagnostic methods reported in the Journal of Autism and Developmental Disorders.

This review summarizes subject selection and diagnostic procedures documented in the Journal of Autism and Developmental Disorders. One hundred forty-two empirical articles published between February 1993 and April 1997 were examined. Reviewers independently evaluated articles using a coding instrument developed by the authors. Results indicated that a majority of researchers reported the use of one or more standard diagnostic criteria in classifying their subjects. However, numerous studies did not report the methods by which the diagnostic criteria were quantified or applied. Additionally, there was a lack of clear specification of inclusion and exclusion criteria for comorbid disorders. Improving the documentation of diagnostic practices in research on autism will benefit researchers and practitioners.

Autistic Disorder↗
PubMed1999

A rapid restriction fragment length polymorphism polymerase chain reaction-based diagnostic method for identification of T-cell lymphoproliferative disorders.

BACKGROUND: Identification of a clonal proliferation of lymphocytes is central to the diagnosis of lymphoma compared with a reactive lymphoproliferation. We propose a novel diagnostic technique based on restriction fragment length polymorphism (RFLP) of amplified polymerase chain reaction (PCR) products of the T-cell receptor -gamma (TCR-gamma) gene rearrangement to rapidly identify monoclonality in T-cell lymphomas and improve diagnosis of malignancy. MATERIALS AND METHODS: DNA from peripheral blood mononuclear cells (PBMCs) of 10 healthy volunteers and 7 T-cell lymphoma patients were isolated and the TCR-gamma was amplified with consensus primers for the different variable (V) and joining (J) segments. Restriction digests were done using BstN1 and the fragments separated via gel electrophoresis. Verification was by Southern analysis. RESULTS: Restriction digests of the 10 healthy controls show a characteristic nine-band digest pattern whereas the restriction digests of the 7 T-cell lymphomas each show altered banding patterns completely distinct from the normal nine-band pattern (Fisher exact test = 0.00005). Sensitivity assays demonstrate the test can detect clonal populations representing 2% of total. This method also enables identification of particular clonal populations. The entire procedure can be performed in one day, does not require radioactivity, and requires only small quantities of specimens. CONCLUSIONS: This RFLP-PCR-based diagnostic method for T-cell lymphomas is specific, sensitive, efficient, and reproducible, and enables the identification of clonally expanded populations of T lymphocytes. It offers the ability to identify particular clonal populations, as with Southern analysis, combined with the benefits of a PCR method.

Blotting, Southern↗
PubMedDate not supplied

[The usefulness of clinical signs and selected diagnostic methods in the diagnosis of tuberous sclerosis in children].

55 children took part in the study. Besides depigmented naevi and epilepsy, echocardiography plays the most significant role in the diagnosis of tuberous sclerosis in children below 2 years of age. In older children, besides dermatologic examination, cranial computerized tomography and abdominal ultrasonography are the most effective methods. This study suggests that the diagnostic effectiveness of different clinical signs and examinations depends on the age of the examined children. An appropriate diagnostic procedure may lead to earlier diagnostic and allows to avoid excessive examinations.

Adolescent↗
PubMed1986

[Up-to-date diagnostic method for the diagnosis of environmental species of the Enterobacteriaceae family].

The Authors propose a new two-steps key for the identification of the species belonging to the Enterobacteriaceae Family. This key can be employed both with standard tube methods and most commercial kits. The proposed method is a simple, easy and rapid one; moreover it considers each genus and species of Enterobacteriaceae Family, associated with human pathology, which has been defined within the month May, 1984.

Enterobacteriaceae↗
PubMed2003

A European survey of diagnostic methods and testing protocols for Clostridium difficile.

OBJECTIVE: To conduct a survey of the methods used in clinical microbiology laboratories in Europe to diagnose infection with Clostridium difficile. METHODS: A questionnaire was devised and sent to a co-ordinating member of the Study Group in each of eight European countries. This co-ordinator was in charge of forwarding the questionnaire to hospital laboratories arbitrarily selected. The number of laboratories in each country was determined on the basis of one laboratory for 10,000 beds of hospitalization. This questionnaire covered different aspects pertaining to Clostridium difficile associated to diarrhea (CDAD) diagnosis such as circumstances of request, criteria used for undertaking C. difficile investigations, methods used for the diagnosis, etc. RESULTS: A total of 212 questionnaires were completed and submitted for analysis: 87.7% of laboratories reported routinely performing C. difficile diagnostic tests. Methods used included toxin detection (93%), culture (55%), and glutamate dehydrogenase (GDH) detection (5.9%). Among the laboratories detecting toxins, different enzyme immunoassays (EIA) and cytotoxicity assays were used in 79% and 17.3% of cases, respectively. Among the different strategies reported, 4.8% were considered suboptimal for the diagnosis of C. difficile infections, but marked discrepancies could be observed between countries. The overall incidence (median) of CDAD was estimated at 1.1 for 1,000 patient admissions. CONCLUSION: The results of this study suggest marked discrepancies between laboratories and also between countries regarding the criteria by which C. difficile is investigated for, and the methods and the strategies that are used for the diagnosis of C. difficile. These discrepancies could be explained by the lack of clear guidelines for C. difficile diagnosis in each country, and by the importance that physicians attach to C. difficile. Precise guidelines for C. difficile diagnosis would be the first step to make possible accurate comparison of the incidence and the epidemiology of CDAD from one hospital to another or from one country to another.

Bacterial Proteins↗
PubMed1985

Chemical and histochemical studies of normal and diseased human gastrointestinal tract. V. A differential diagnostic method for the histochemical classification of glycoproteins.

A differential diagnostic scheme is described for the division of colonic epithelial glycoproteins into eleven histochemically distinct classes. The scheme depends upon the use of seven histochemical techniques which, collectively, permit the differential staining of O-sulphate ester, sialic acid and its side chain O-acyl variants and vicinal diols located on carbohydrate residues other than sialic acids. Elements of the scheme also provide a general approach to the classification of epithelial glycoproteins in anatomic sites other than the colon. Application of the scheme permitted the classification of the epithelial glycoproteins in the mucosa 0.5-5.0 cm from human colonic tumours and provided direct confirmation of previous observations that changes from normal in the relative proportions of either side chain O-acylated sialic acids or sialic acids and O-sulphate esters can occur independently of one another.

Colonic Neoplasms↗
PubMed2004

[Evaluation of diagnostic methods for Helicobacter pylori infection].

In Japan, the noninvasive diagnostic tests currently approved for health insurance by the Ministry of Health are the serology test, the 13C-UBT test and the stool antigen test. The serology(antibody detection) test is useful for pretreatment screening, but because it reflects an immunologic response, false negatives are seen in patients with diseases such as rheumatoid arthritis and connective tissue diseases, and in the elderly. Furthermore, the serology test is difficult to use in the clinical setting, because 6 months or more is needed for the antibody titer to fall, after eradication therapy. For UBT, the expensive 13C-UBT is used. In view of the anticipated increase in testing, a test that is relatively inexpensive, simple, accurate and safe is needed. The stool antigen test has become available, and the test has been validated for accuracy. The stool antigen test is useful for the diagnosis of H. pylori infection before and after treatment in Japanese population.

Helicobacter Infections↗
PubMed1995

Evaluating four diagnostic methods with acute abdominal pain cases.

Contemporary work in medical decision support is characterized by a multitude of methods. To investigate their relative strengths and weaknesses, we built four diagnostic expert systems based on different methods (Bayes, case-based classification, heuristic classification) for analysis of the same set of 1254 cases of acute abdominal pain previously documented in a prospective multicenter study. The results of the comparative evaluation indicate that differences in overall performance are relatively small (statistically not significant). The performance depends more on the quality of the knowledge base and the case data than on the inference methods of the expert systems. Methods relying exclusively on empirical knowledge (Bayes, case-based classification) tend to have slightly higher overall performance scores due to a diagnostic bias toward ordinary and common diseases. By contrast, methods operating with expert knowledge (e.g., heuristic classification) perform slightly worse overall, but are more sensitive toward uncommon (serious) diseases.

Abdominal Pain↗
PubMed1998

Impact of the diagnostic methods on the therapeutic strategies.

Over the last 25 years the diagnostic approaches and therapeutic strategies of breast cancer have dramatically changed. The relationship between diagnosis and therapy has gradually become more complex due to the ever more sophisticated diagnostic tools (mammographic screening, digital mammography, magnetic resonance, SPECT scan and FDG-PET), which have improved resolution limits and accuracy, and also due to the different therapeutic planning applied to breast cancer in these years (conservative surgery, neo-adjuvant chemotherapy, axillary dissection or not). Thus, in this paper, we have briefly analyzed the many open questions in breast cancer management and the clinical challenges of present diagnostic tools in relation to pre-, peri- and postoperative phases, and to therapeutic strategies in general. The main goal of mammographic screening is to detect early invasive cancers and to treat them at the first useful moment. However, at which age should one begin screening, and what is the impact on overall survival, the cost-effectiveness, and, most of all, the best operative approach to suspect lesions? Can digital mammography give a better quality of imaging with respect to conventional mammography? Does unexpected multicentricity and/or multifocality, which is sometimes showed by magnetic resonance, have any clinical relevance? Is this technique really better than traditional methods for the identification of local recurrence? Is scintimammography able to improve the low diagnostic accuracy of mammography on non-palpable breast lesions? Moreover, at present, the need for axillary dissection and its therapeutic and staging value is deeply debated: however, clinical detection of axillary metastases is not a reliable diagnostic tool and there are no conventional radiologic techniques to be used: recently nuclear medicine imaging has provided various approaches, such as SPECT scan with different tracers, FDG-PET, or lymphoscintigraphy with gamma probe sentinel biopsy: there are not only methodologic but also phylosophic differences in using these techniques. Neo-adjuvant chemotherapy has allowed a dramatic reduction of primary breast cancer with a replanning of the surgical approach to large breast tumours but, at the same time, has posed new questions such as the adequacy of diagnostic pre- and perioperative revaluation. Finally, does postoperative follow-up take advantage of intensive diagnostic programs and are there therapeutic margins which would improve survival of patients with metastatic disease? This paper is an attempt to analyze the answers given in the literature. Nevertheless, at present, this matter is globally in progress and a scientific debate will provide, in the near future, a new promising scenario for breast cancer management.

Age Factors↗
PubMed1995

[The efficiency of using diagnostic methods in the polyclinic].

Due to the formation of consulting and diagnostic polyclinics (CDP) in the Russian Armed Forces the significance of multipurpose diagnostical process in military garrison has met a considerable upgrade. The authors take into account the experience of CDP work and recommend to make a rational centralization of diagnostical process and determine the outlook for the development of diagnostical technologies adapted for different polyclinics, making a rational use of modern diagnostical equipment and enhancing the qualification of personnel occupied with diagnostical work.

Diagnosis↗