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In this article are examining the requirements to diagnostic methods in periodontics. Author comprises clinical radiology and cytomorphometric methods in diagnostics of chronic gingivitis and initial periodontitis.
In this symposium, the speakers have discussed the progress of the current diagnostic methods available for the diagnosis of viral hepatitis type C, and the accuracy and reproducibility at hand now, or which should be attained in the near future. Since the first appearance of ELISA (Ortho) and RIA (Dainabot) kit, the screening of infected blood with HCV from donors has been very successful. Posttransfusion hepatitis following infected blood transfusion has clearly decreased. The carrier rate of HCV in the Ehime prefecture is reported to be 1.85% in males and 1.25% in females. Diagnostic methods of the second generation such as ELISA and RIBA using C200 and C22 (core) protein as antigens yield 92.6 to 100% positive results in a diagnosis of NANB hepatitis following anti-hemophilic sera injection or hemodialysis. Detection of HCV RNA by RT-PCR procedure promised accurate diagnosis. Using such diagnostic methods, the majority of the patients with NANB chronic hepatitis were diagnosed as having CH type C. IgM anti-C 100-3 antibody was not useful for early diagnosis of patients infected with HCV, but the titer was useful for determining the therapeutic response of patients on INF therapy. The route of infection was concluded to be mostly horizontal rather than vertical (maternal-child), though a few cases were present suggestive of maternal transmission. Interferon therapy against patients with CH type C was effective in CAH 2A, but only a poor response was observed in patients with CAH 2B.
Development of diagnostic methods for orbital diseases have practically revolutionized the approach to the patient with orbital disease. These newer methods have helped the clinician to improve the accuracy of the clinical diagnosis prior to biopsy, to localize the area to be biopsied, and to prevent inappropriate surgery. These techniques have also allowed the pathologist to render more definitive diagnosis. These methods include ultrasound, computerized axial tomography, nuclear magnetic resonance imaging, fine-needle aspiration biopsy, histochemistry, immunohistochemistry and electron microscopy. The techniques are complementary, and use of each depends on the clinical situation. Some techniques require collaboration between the surgeon and pathologist to assure proper fixation and preparation of tissues.
Diagnostic methods in restorative dentistry are still based on history taking and clinical examinations. Clinical findings, however, reflect only processes in the microscopic range. The correlation of macroscopic symptoms and histological findings is indispensable. In dentistry, and especially in restorative dentistry, too, laboratory findings will assume more and more importance as already is the case in periodontology and cardiology.
It is assumed that about 10% of individuals infected with M. tuberculosis (Mtb) develop tuberculosis (Tb), and the remaining 90% suppress contain Mtb through their immune systems, but have a latent tuberculosis infection (LTBI). To effectively control Tb, it is essential to detect individuals with LTBI in a Tb outbreak and provide chemoprophylaxis for them. Until recently, the tuberculin skin test (TST) has been the only diagnostic method for LTBI. However, the specificity of TST is low, because the purified protein derivative (PPD) used for TST contains numerous Mtb antigens that are almost identical to BCG antigens or similar to non-tuberculous mycobacterium (NTM) antigens. For this reason, TST may produce positive results in BCG-vaccinated individuals or NTM-infected individuals without Mtb infection. Therefore, it is very difficult to diagnose LTBI in Japan, where BCG vaccination is widely administered. In addition to this, TST has other defects, such as technical variations for injecting PPD or measuring the TST response, the necessity of a return visit to the doctor to measure the TST response 2 days after PPD injection, and the booster effect through reinjection of PPD. More recently, a new diagnostic method that can overcome these defects in TST, QuantiFERON TB-2G (QFT-2G), has been developed. In QFT-2G, two Mtb-specific antigens, ESAT-6 and CFP-10, are used to stimulate whole blood, and based on produced interferon-gamma (IFN-gamma), Mtb infection is diagnosed. Since ESAT-6 and CFP-10 are absent from all M. bovis BCG substrains and most of NTM including M. avium, M. intracellulare, but are present in tuberculosis complex (M. tuberculosis, M. bovis, M. africanum) and only a few strains of NTM, QFT-2G is not affected by prior BCG vaccination nor most of NTM infections. Moreover, as measurement of IFN-gamma can be carried out by machines on the next day following the blood draw, more objective results are obtained more quickly than with TST. It is not necessary to consider the booster effect in QFT-2G as PPD is not injected, nor to revisit the doctor. Thus, QFT-2G overcomes the defects of TST described here. From a clinical trial of QFT-2G in which the subjects were smear-positive, untreated Tb patients and BCG-vaccinated healthy individuals, it has been demonstrated that the specificity and sensitivity of QFT-2G are 98.1% and 89.0%, respectively, and QFT-2G is an excellent diagnostic method. Furthermore, many contact investigations have shown that QFT-2G detects not only active Tb but also LTBI. Several data indicate that frequency of contact with Tb patients correlates well with QFT-2G positive rates in contact investigations. The validity and usefulness of diagnosing LTBI by QFT-2G have been suggested in other countries. In many contact investigations, it has been shown that most contacts who had been diagnosed as LTBI based on TST results were QFT-2G negative, suggesting that as a result, many unnecessary chemoprophylaxes were indicated. On the contrary, many QFT-2G positives were identified in those who were diagnosed to be uninfected with Mtb based on TST. Therefore, as the wide spread of QFT-2G testing in contact investigations would prevent unnecessary chemoprophylaxes and detect true infected individuals more accurately, we hope that more effective Tb control could be performed. Although QFT-2G is an excellent diagnostic method, it is still new, and some questions remain to be answered. For example, the period of converting QFT-2G positive after Mtb infection, alteration of long-term QFT-2G responses after Mtb infection, and the effects of treatment for Tb or LTBI are not fully understood. The behavior of QFT-2G in infants or children is not understood either. Especially in infants, the problem of the blood volume required for the QFT-2G test is the major issue. We are working on these issues to provide more appropriate directions for QFT-2G users, and hope that we can contribute to Tb control.
OBJECTIVE: To develop a polymerase chain reaction (PCR)-based diagnostic method for bacterial vaginosis using bacterial vaginosis-associated anaerobes. METHODS: A multiple PCR assay was developed using primers specific to 16S ribosomal deoxyribonucleic acid (DNA) (Mobiluncus mulieris and Mobiluncus curtisii), nanH (Bacteroides fragilis), and an internal spacer region of ribosomal DNA (Gardnerella vaginalis). The vaginal swabs from pregnant and nonpregnant women were examined by Gram stain-based Nugent scoring system. One hundred seventy-two samples of 853 Gram stain-interpretable samples were randomly selected and subjected to multiplex PCR assay. RESULTS: The sensitivity of the PCR assay ranged from 10 to 10 colony-forming units per vaginal swab. The prevalence of the bacterial vaginosis, intermediate, and normal categories was found by Nugent scoring system to be 21.6% (184/853), 26.0% (222/853), and 52.4% (447/853), respectively. By the multiplex PCR-based diagnostic method, 20.3% (35/172) of the samples were identified as bacterial vaginosis. The diagnostic sensitivity, specificity, positive predictive value, and negative predictive value of multiplex PCR in comparison with Gram stain examination were 78.4% (95% confidence interval [CI] 65.1%, 91.6%), 95.6% (95% CI 92.1%, 99.0%), 82.9% (95% CI 70.4%, 95.4%), and 94.2% (95% CI 90.3%, 98.1%), respectively. CONCLUSION: This multiplex PCR can be used as a diagnostic or screening test for bacterial vaginosis.
OBJECTIVE: To provide a literary overview of the complications associated with the invasive prenatal diagnostic methods in the 1st and 2nd trimester of pregnancy. DESIGN: A summarising article. SETTING: Mother and Child Care Institute, Prague. METHODS: Compilation of data from professional literature. RESULTS AND CONCLUSION: The global trend is characterised by the effort to move prenatal diagnostics into the period of the first trimester. The invasive diagnostic methods of this period - sampling of chorionic villi and timely amniocentesis are subjects of a number of discussions, which deal primarily with their reliability and safety. The main indicator is the evaluation of foetal losses occurring in connection with the action. So far, the safest method is second-trimester amniocentesis; for early diagnostics, the trans-abdominal sampling of chorionic villi is preferred to transcervical one and to early amniocentesis.
Non-group-A rotaviruses have been implicated with increasing frequency as causes of acute gastroenteritis in humans and other animals. However, the incidence and significance of infection with these agents, as well as appropriate diagnostic strategies for making these determinations, are largely unknown. Studies to make these determinations could be more accurately conducted if the relationship between the viral replication kinetics and the particular diagnostic method used is understood. We thus utilized the murine model of group B rotavirus infection to establish the viral replication kinetics by a variety of commonly used diagnostic methods. Enzyme immunoassay, routine negative-stain electron microscopy, solid-phase immunosorbent electron microscopy, polyacrylamide gel electrophoresis, and a dot hybridization assay were used in these studies. By enzyme immunoassay, 100% of experimentally infected suckling rats tested positive for group B rotaviral antigens at 1, 4, and 5 days postinoculation. However, only 70 and 20% of infected animals tested positive at days 2 and 3 postinoculation, respectively. Dot hybridization with a complementary DNA probe also suggested a biphasic pattern of viral antigen excretion. Evidence of the virus causing infectious diarrhea in infant rats was found only on day 1 postinoculation in samples examined by routine negative-stain electron microscopy and by polyacrylamide gel electrophoresis. Rotaviruslike particles were observed by solid-phase immunosorbent electron microscopy on days 1, 2, and 4 after viral inoculation suckling rats but were clearly the most numerous on day 1. Additionally, the enzyme immunoassay was used to quantitate the kinetics of group B rotaviral replication in the intestines of the experimentally infected animals. Levels of murine group B rotaviral antigens in intestinal samples peaked on days 1 and 4 postinoculation; however, only peak 1 represented actual intraepithelial replication of the virus. These studies thus indicate that early sample collection and selection of the appropriate diagnostic method are critical if the incidence and significance of group B and possibly other non-group-A rotaviral infections are to be accurately assessed.
This article is a comprehensive description of diagnostic methods for detection of RNA respiratory viruses - respiratory syncytial virus RSV, influenza A and B viruses, parainfluenza 1, 2 and 3 viruses, coronaviruses and rhinoviruses--from cell culture to molecular biology methods. Both patients and medical personnel appear to be at risk of viral infection, specially during the winter season. Moreover, many health care units lack viral diagnostic facilities; therefore, it is essential for medical personnel to have an understanding of the etiology, mechanisms of transmission and of all disposable today diagnostic methods of RNA respiratory viruses. Patients at greatest risk of acquiring nosocomial viral respiratory disease are children, patients with immunodeficiency and patients treated in intensive care.
OBJECTIVE: To investigate the information acquired through the four diagnostic methods of traditional Chinese medicine in patients with bronchial asthma, and to classify the syndrome types. METHODS: Four hundred and thirty patients with bronchial asthma were randomly investigated. The information acquired through the four diagnostic methods was recorded and the database was established by Amos software, and then the data were analyzed by confirmatory factor analysis (CFA). RESULTS: After analyzing the data with 4 factors, 5 factors and 6 factors, we found that the results of CFA with 6 factors were in accordance with clinical practical experience. CONCLUSION: According to the results of CFA with 6 factors and with the standard regression coefficient 0.4 as primary and secondary critical points, the syndromes in patients with bronchial asthma can be classified into 5 types, which are syndromes of cold fluid retained in lung, phlegm-heat obstructing lung, wind-phlegm blocking lung, qi deficiency of lung and kidney and qi deficiency of spleen.
Different diagnostic methods used for the screening of breast cancer such as clinical examination of breasts, self-examination and mammography are reported. A detailed explanation is given regarding reasons for the indication of mammography which include latent symptoms in non-palpable lesions and asymptomatic cases, as well as the advantages of this diagnostic method. The structure and design of the Subprogram for Early and Preclinical Diagnosis of Breast Cancer are explained and data on the situation of breast cancer in the country are reported. The goal of the survey applied and the structure of the mobile car is briefly presented, as well as the management of the different classifications such as low, mid, high and very high risk. The purpose of this paper is to describe the developmental and supporting actions undertaken by the health staff, especially by the nursing and health promotion staff.
The author draws attention to general principles which must be respected in the selection and interpretation of diagnostic methods. He discusses the importance of basic characteristics of the diagnostic test (reliability, accuracy, sensitivity, specificity, predictive value) and their application in the examination process. He explains the importance of ROC analysis in the selection of the optimal diagnostic method. He refers to the criteria which must be taken into account when introducing and evaluating a new examination method.
BACKGROUND: Onychomycosis is a common problem seen in clinical practice. Given the differential diagnosis of dystrophic nails, it is helpful to obtain a definitive diagnosis of dermatophyte infection before the initiation of antifungal therapy. Potassium hydroxide (KOH) preparation and fungal culture, which are typically used in the diagnosis of these infections, often yield false-negative results. Recent reports have suggested that nail plate biopsy using periodic acid-Schiff (PAS) (Bx/PAS) stain may be a very sensitive technique for the diagnosis of onychomycosis. OBJECTIVE: The purpose of this study was to compare KOH preparation, culture, Bx/PAS stain, and calcofluor white (CW) stain in the diagnosis of onychomycosis and to determine their sensitivity and specificity. METHODS: We evaluated 105 patients with suspected onychomycosis using 4 diagnostic methods: KOH preparation, culture, Bx/PAS, and CW stain. CW stain binds to cellulose and chitin, and fluoresces when exposed to UV radiation. It is a highly sensitive and specific technique for the detection of dermatophytes. To determine the clinical usefulness and performance characteristics of each test, CW was chosen as the gold standard for statistical analysis. RESULTS: Of the patients, 93 had at least 1 of the 4 diagnostic methods positive for the presence of organisms. The following were calculated for each test: sensitivity; specificity; positive predictive value; and negative predictive value. The sensitivities of each of the techniques were as follows: KOH 80%; Bx/PAS 92%; and culture 59%. Both KOH and Bx/PAS methods were more sensitive than culture (P =.00002). Bx/PAS was also more sensitive than KOH (P =.03). The specificities were as follows: KOH 72%; Bx/PAS 72%; and culture 82%. The positive predictive value calculated for the different techniques were: KOH 88%; Bx/PAS 89.7%; and culture 90%. In terms of negative predictive value, the results were: KOH 58%; Bx/PAS 77%; and culture 43%. CONCLUSION: Bx/PAS is the most sensitive method for the diagnosis of onychomycosis. It is also superior to the other methods in its negative predictive value. It is indicated if other methods are negative and clinical suspicion is high, and potentially is the single method of choice for the evaluation of onychomycosis.
The presence of Campylobacter pylori in gastric mucosa is a proof of active gastritis. Diagnostic methods are based on endoscopy: culture--histology--cytology--urease test, or on noninvasive tests: C14 urea breath test and serology. The principles, results (sensitivity--specificity), advantages and problems of each test are discussed as well as the choice of a diagnostic method. In practice, we recommend the use of two methods, a morphological one (histology or cytology) and another based on bacterial activity (urease test or culture).
The authors studied the informative value of various diagnostic methods: ultrasonic examination (USE), computed tomography (CT), magneto-resonance tomography (MRT), phlebography with separate collection of blood from the inferior vena cava and its hormonal investigation in Itsenko-Cushing's disease (52 cases). All patient underwent operation, and because of this the changes detected in the adrenals by various diagnostic methods of examination were compared with the morphological findings. Three patients were subjected to bilateral adrenalectomy. Morphological study of the adrenals revealed diffuse hyperplasia of the cortex in 17 cases, macro- and microadenomas in hyperplasia of the adrenals in 23, and diffuse-nodular hyperplasia in 15 cases. In macroadenomatosis identification, the informative value of MRT was 77.8%, CT 66.6%, and USE 22.2%. MRT was most informative in detection of microedenomatosis and diffuse-nodular hyperplasia--82.3% of cases; the respective values for CT and USE were 71.4% and 56.5%. The quantitative parameters of the adrenal tissue were studied in MRT: relaxation time (T-2) and the value of relative signal intensity (E). The value of relative signal intensity was lower in micro-macroadenomatosis than in diffuse and diffuse-nodular hyperplasia. The use of the quantitative parameters (T-2 and E) increases the diagnostic possibilities of MRT and provides for a more authentic idea of the character of the pathological changes in the adrenal tissue. Precise verification of the pathological process in the adrenal cortex allows the optimal treatment to be chosen, adrenalectomy to be considered in time, and the side of the operation to be correctly determined.
OBJECTIVES: To examine the diagnostic value of gastroscopy and upper abdominal ultrasound, which are frequently used as primary tests in dyspeptic patients in general practice. To test the influence of age for accuracy of both diagnostic methods. DESIGN: Clinical study. SETTING: Four health centres in Kuopio Province, Finland. SUBJECTS: Four hundred unselected consecutive dyspeptic patients (91 less than 45 years of age) who consulted their general practitioners. MAIN OUTCOME MEASURES: Sensitivity, specificity, positive and negative predictive values (PV), efficiency and usefulness index (UI) were calculated for upper abdominal ultrasound and for gastroscopy in detecting the causes of dyspepsia in primary care. Final diagnosis was determined after one year follow-up. RESULTS: The sensitivity of upper abdominal ultrasound in detecting the cause of dyspepsia was 0.07, the specificity 0.91, PV+ 0.36, PV- 0.56, and UI -0.001. Ultrasound was not more efficient in older patients. Gastroscopy was the most efficient method with a sensitivity of 0.75, specificity 1.00, PV+ 0.99, PV- 0.83 and UI 0.56. The usefulness of gastroscopy was even better among patients over 45 years of age. CONCLUSIONS: The usefulness of upper abdominal ultrasound is low regardless of patient's age. Gastroscopy is superior to upper abdominal ultrasound as a first line diagnostic method in diagnosing dyspepsia, especially among patients over 45 years of age.
A new method for DNA diagnostics based on template-directed primer extension and detection by fluorescence resonance energy transfer is described. In this method, amplified genomic DNA fragments containing polymorphic sites are incubated with a 5'-fluorescein-labeled primer (designed to hybridize to the DNA template adjacent to the polymorphic site) in the presence of allelic dye-labeled dideoxyribonucleoside triphosphates and a modified Taq DNA polymerase (Klentaq1-FY). The dye-labeled primer is extended one base by the dye-terminator specific for the allele present on the template. At the end of the genotyping reaction, the fluorescence intensities of the two dyes in the reaction mixture are analyzed directly without separation or purification. This homogeneous DNA diagnostic method, which we call the template-directed dye-terminator incorporation assay, is shown to be highly sensitive and specific and is suitable for automated genotyping of large numbers of samples.
BACKGROUND: To know the influence of upper gastrointestinal bleeding in diagnostic methods of H. pylori infection. METHODS: We prospectively studied patients with peptic ulcers: 55 with upper gastrointestinal bleeding and 62 without upper gastrointestinal bleeding. We analysed the results of culture, urease test, Gram, histology and serological test IgG and IgA in both groups. H. pylori infection was determined by a positive culture or positive urease test and histology. RESULTS: Patients with upper gastrointestinal bleeding were older, but there were not statistical differences in sex, H. pylori prevalence infection or duodenal or gastric ulcers between patients with and without upper gastrointestinal bleeding. 78% having H. pylori infection. The urease test had a false negative rate in patients with upper gastrointestinal bleeding of 22% but only 3% in patients without upper gastrointestinal bleeding (p < 0.05). The culture, histology and Gram had higher false negative rate in upper gastrointestinal bleeding group than in non upper gastrointestinal bleeding group but without statistical significance. All patients with false negative urease test had antral culture positive. CONCLUSIONS: Urease test has a high false negative rate when is studied in patients with peptic ulcers and upper gastrointestinal bleeding. Caution should be made if urease test was used alone for diagnosis in patients with upper gastrointestinal bleeding. Urease test and culture together could be a good diagnostic method.