Routine Diagnostic Methods Research Articles

Usefulness of the BTA statTest for the diagnosis of bladder cancer

Objectives. To evaluate the usefulness of the Bard BTA stat Test in the diagnosis and follow-up of bladder cancer and to compare this test to cytologic analysis and cystoscopy, routine diagnostic methods. Methods. Three hundred seventy-nine patients being followed up because of bladder cancer or with symptoms suggestive of bladder cancer underwent cystoscopy, cytologic analysis, and the BTA stat Test using a recently voided urine sample. In suspected cases, transurethral resection and histopathologic analysis were performed. Results. Of the 379 patients, 235 proved to have bladder cancer and 144 did not. The sensitivity was 73.62% for the BTA stat, 61.70% for cytologic examination, and 99.57% for cystoscopy. The specificity was 83.33% for the BTA stat, 92.36% for cytologic analysis, and 85.42% for cystoscopy. The BTA stat Test’s sensitivity for grades 1, 2, and 3 tumor was 47.27%, 69.15%, and 95.35%, respectively. The sensitivity of cytologic analysis was 30.91%, 55.32%, and 88.37%. The BTA stat Test’s sensitivity for stage was 45.65% in Stage Ta, 75.52% in T1, and 95.56% in Stage T2-4; the cytologic results were 28.26%, 65.03%, and 84.44%, respectively. The combination of both tests improved the sensitivity and decreased the specificity slightly. Conclusions. The high sensitivity of the BTA stat Test, together with the data obtained from the parameters used for the evaluation of the test, demonstrate the better results of the BTA stat Test compared with cytologic analysis, making it a thoroughly valid diagnostic tool in the diagnosis of bladder cancer. In our opinion, the BTA stat Test can replace the use of cytologic analysis in the diagnosis of bladder cancer, but not the use of cystoscopy.

A "virtual hearing aid" for comparing hearing aids in children: a double-blind crossover study.

In this study, a "virtual hearing aid" was used to compare different types of hearing aids. A digital hearing aid (Oticon DigiFocus Compact) and an analogue, automatic reference hearing aid were compared in a group of 17 schoolchildren (median age: 10 years) with moderate to severe, symmetrical, sensorineural hearing loss. Differences in performance were assessed using routine diagnostic methods (speech recognition performance tests, loudness scaling), subjective assessments (questionnaires) and the "virtual hearing aid". Guaranteeing double-blind testing conditions, the "virtual hearing aid" offers the possibility to directly compare individual in-situ recordings of different hearing aids. In contrast to the clear subjective preferences for the digital hearing aid, we could not obtain any significant results with routine diagnostic methods. Using the "virtual hearing aid", the subjective comparison and speech recognition performance tasks yielded significant differences. The "virtual hearing aid" proved to be suitable for directly comparing different hearing aids under double-blind testing conditions.

Aplicação clínica da laparoscopia em eqüinos

A laparoscopia, apesar de conhecida há muitas décadas como método de diagnóstico nas afecções da cavidade abdominal dos equinos, tem sido mais enfocado nos últimos anos, passando a ser indicada rotineiramente nos casos de peritonite, encarceramento, necrose e rupturas intestinais, duodenojejunite, aderências, criptorquidismo, neoplasias, abscessos, cistos e hematomas abdominais, assim como técnica de acompanhamento visual para realização de biópsia em órgãos parenquimatosos. O adequado conhecimento da técnica e suas aplicações permitem ao clínico dispor de importante ferramenta em casos nos quais os métodos não invasivos foram infrutíferos na determinação de diagnóstico preciso.

Primary diagnosis of foot-and-mouth disease by reverse transcription polymerase chain reaction

Universal and serotype-specific primer sets were used in simple reverse transcription polymerase chain reaction (RT-PCR) assays on field samples of epithelium and vesicular fluid to determine their suitability for primary diagnosis of all seven serotypes of foot-and-mouth disease (FMD). The specificity of reactions was confirmed by using other vesicular disease viruses, namely: swine vesicular disease virus, vesicular stomatitis virus and three vesiviruses. This resulted in the identification of a universal O/A/C/Asia 1 primer set (1F/1R) located in the 5′ untranslated region (UTR) of the FMD virus genome for the successful detection of virus of these serotypes in clinical samples although this primer set detected FMD virus of the SAT1/2/3 serotypes less efficiently. The 5′ UTR universal primer set could be used for the primary diagnosis of FMD in conjunction with the routine diagnostic methods of virus isolation in cell culture and ELISA, although a more favourable reaction would be expected with FMD viruses of the O/A/C/Asia 1 group than with those of the SAT serotypes. The other examined universal and serotype-specific primer sets, located principally in the P1 capsid-coding region, were generally inferior to the 5′ UTR universal primer set. It is envisaged that this evaluation of primers will lead to the development of alternative PCR strategies, for example nested PCR formats, with concomitant improvement in the speed of primary diagnosis of FMD which under present procedures can be lengthy.

Diagnosis and Identification of GastricHelicobacterSpecies by Polymerase Chain Reaction in Dogs

Helicobacter spp. are almost ubiquitously present in the stomach of dogs. Various Helicobacter species have been isolated, however, their identification by routine diagnostic methods is impossible, culture is cumbersome and not sensitive. We developed and validated a PCR assay based on amplification of the urease B gene for the detection of Helicobacter species in gastric biopsy specimens of dogs against a set of established invasive and non-invasive detection methods. Altogether, urease B gene PCR had a sensitivity of 98% identifying 59 of 60 infected dogs in a series of 65 dogs. Direct identification of helicobacters present in gastric biopsies was obtained by species-specific PCR based on the urease gene with a newly developed PCR for H. bizzozeronii/H. salomonis and in established PCR assays for H. felis and ' H. heilmannii '. In the 59 dogs positive by the urease B gene PCR the colonizing Helicobacter was identified by species specific PCR and/or culture as H. bizzozeronii/H. salomonis in nineteen, ' H. heilmannii ' in twelve, H. felis in seven and a Helicobacter sp. in two; no identification was obtained in 31 dogs and a double infection was found in six dogs. Results of species-specific PCR were concordant with conventional and molecular identification of Helicobacter strains isolated in six culture positive dogs. These findings indicate that urease B gene PCR is accurate in diagnosing a helicobacteriosis in dogs, and that various Helicobacter species can reliably be identified by species specific urease PCR. Keywords: canine, spiral organisms, urease gene, histology.

Improved detection of citrus psorosis virus using polyclonal and monoclonal antibodies

Citrus psorosis is a serious and widespread disease associated with citrus psorosis virus (CPsV), a novel filamentous negative‐stranded virus in the genus Ophiovirus. Laborious and costly indexing on test plants has been the only routine diagnostic method available, but recently an antiserum usable in double antibody sandwich (DAS) ELISA has been prepared. Here, major improvements to the DAS‐ELISA protocol, a new purification method, and production of two monoclonal antibodies (mabs) to CPsV, an IgG and an IgM are reported. A highly sensitive triple antibody sandwich (TAS) ELISA making use of the mabs is described. In glasshouse citrus the homologous virus was still detectable at a tissue dilution of 1/6250 in DAS and at 1/31250 in TAS‐ELISA. Both the DAS and IgG mab‐TAS formats detected all CPsV isolates so far tested (from Argentina, Italy, Lebanon, Spain and the USA). A few isolates were not detected by the IgM mab.

Predictive value of bone mineral density and Singh Index for the in vitro mechanical properties of cancellous bone in the femoral head

Objective: The purpose of this study was to assess the validity of two methodically different radiological parameters, bone mineral density and Singh Index, for the prediction of mechanical properties in femoral cancellous bone. Design: Coherence between in vitro evaluation of mechanical properties and bone mineral density on a femoral bone slice, combined with clinical determination of Singh Index on ordinary X-rays. Background: It is accepted that bone densitometry yields excellent prediction of mechanical bone quality, but is considered to be an expensive and not widely available method for routine diagnostics in clinical practice. In contrast, determination of Singh Index is an inexpensive and simple technique, but its predictive value for bone mechanics is still controversially discussed. Methods: We used cortically confined bone slices from 33 femoral heads. Bone mineral density was measured using quantitative computed tomography. Strength and elastic modulus were assessed by mechanical testing in up to 39 circular positions on each slice. Singh Index was evaluated on ordinary X-rays of the hip by two independent readers. Results: Bone mineral density showed strong correlations with strength ( r=0.86) and good correlations with elastic modulus ( r=0.68). Singh Index correlated well with strength ( r=0.70), but only moderately with elastic modulus ( r=0.52). Conclusions: The strong validity of bone mineral density in predicting mechanical bone quality was confirmed. Singh Index assessment permits a rough estimation of mechanical strength in particular and can therefore be used for first estimations of mechanical bone quality, provided that readings were performed by experienced clinicians. Relevance Reduced mechanical bone quality induces an increase in fracture risk. Whenever performed, bone mineral density measurement allows an excellent evaluation of the mechanical properties of cancellous bone in the hip and can be recommended for screening evaluations. The assessment of Singh Index on ordinary X-rays of the hip is an inexpensive and simple method, and allows a rough estimation of the mechanical quality of the femur. However, due to its subjective character, its predictive value for the mechanical quality of bone in individual patients remains uncertain.

Is Streptococcus Pneumoniae the leading cause of pneumonia of unknown etiology? a microbiologic study of lung aspirates in consecutive patients with community-acquired pneumonia

PURPOSE: Although a wide variety of recognized pathogens can cause community-acquired pneumonia, in many patients the etiology remains unknown after routine diagnostic workup. The aim of this study was to identify the causal agent in these patients by obtaining lung aspirates with transthoracic needle aspiration. SUBJECTS AND METHODS: During a 15-month period, all consecutive patients with community-acquired pneumonia who were eligible for transthoracic needle aspiration were enrolled in the study. In addition to conventional microbial methods (culture of blood and sputum, serologic studies), we performed cultures and genetic and antigen tests for common respiratory pathogens in lung aspirates. RESULTS: The study group consisted of 109 patients. Conventional microbial studies identified an etiology in 54 patients (50%), including Mycoplasma pneumoniae in 19 patients, Chlamydia pneumoniae in 9 patients, and Streptococcus pneumoniae in 9 patients. Among the remaining 55 patients, study of the lung aspiration provided evidence of the causal agent in 36 (65%). In 4 additional patients with a single microbial diagnosis by conventional methods, the lung sample provided evidence of an additional microorganism. The new pathogens detected by lung aspiration were S. pneumoniae in 18 patients, Haemophilus influenzae in 6 patients, Pneumocystis carinii in 4 patients, and C. pneumoniae in 3 patients; other organisms were identified in 4 patients. CONCLUSIONS: In our study, S. pneumoniae was the leading cause of community-acquired pneumonia, accounting for 25% of all cases, including about one-third of the cases the cause of which could not be ascertained with routine diagnostic methods.

A comparison of PCR with virus isolation and direct antigen detection for diagnosis and typing of genital herpes

Patients attending the genitourinary medicine clinic at Watford General Hospital, UK, were examined for clinical signs of genital herpes infection. Genital swabs were taken from 194 patients (126 female, 68 male) who presented with genital ulceration or symptoms which were suggestive of genital herpes infection. Swabs from these patients were tested by three methods: (i) Detection of herpes simplex virus (HSV) antigen by direct HSV enzyme immunoassay (EIA), (ii) HSV isolation in Vero cell culture and (iii) HSV polymerase chain reaction (PCR). HSV was detected in 76 patients (39%) by EIA, in 93 (48%) by isolation in cell culture, and in 115 (59%) by PCR. Isolation by cell culture has been considered as the "gold standard" for the detection of HSV in genital lesions, but in this study HSV PCR was significantly more sensitive. Comparison of the three methods was as follows: Cell culture vs. PCR: Sensitivity 93/115 (80.9%), Specificity 79/79 (100%). HSV EIA vs. PCR: Sensitivity 75/115 (65.2%), Specificity 78/79 (98.7%). HSV EIA vs. Cell culture: Sensitivity 75/93 (80.7%), Specificity 100/101 (99%). EIA was less effective in detecting HSV among recurrent than among first episode infections, in comparison to culture or HSV PCR. This is the first comparison of HSV PCR with two other routine diagnostic methods for confirming genital herpes infection in a symptomatic population. The infecting HSV type was identified by restriction digestion of 108 HSV amplicons: HSV-1:37/108 (34%), HSV-2:71/108 (66%). In this population HSV-1 causes a significant proportion of genital herpes cases, and HSV-1 genital infection was detected in significantly more first episode infections (40.3%) than among recurrent infections (22.2%).

A non-isotopic method for the detection of telomerase activity in tumour tissues: TRAP-silver staining assay.

Telomerase activity has been observed in a high proportion of specimens from a wide variety of human malignant tumours, but not in non-neoplastic tissues. Measurement of telomerase activity is a...

In vitro susceptibility testing of Candida species against fluconazole using the microdilution test with Alamar Blue

The investigation of susceptibility of Candida species to fluconazole was performed in microdilution to a supplemented HR-medium. The sufficient reproducibility of the test was verified using special control isolates and isolates of patients. The excellent applicability of the method in routine diagnostics was evaluated by in vitro testing of susceptibility of 279 Candida isolates from patients being colonised or suffering from endomycoses. The Candida species showed different susceptibility against fluconazole: 96% of the C. albicans isolates were sensitive, 55% of the C. glabrata isolates had a reduced sensitivity, and 26% were resistant against fluconazole (MIC > 25 micrograms/ml). C. krusei isolates were highly resistant (9 of 11 strains).

PCR in diagnosis of pneumocystosis of rats.

Polymerase chain reaction (PCR) is a powerful technique to detect scanty amount of DNA from living organisms. The present study intended to develop specific primers for PCR diagnosis of pneumocystosis and to evaluate diagnostic efficacy by preparation of template DNAs from invasive BAL fluid and also to screen serum or blood as a non-invasive specimen. Albino rats of Wistar or Fischer strains were experimentally infected by Pneumocystis carinii. Extracted DNAs or cell lysates of their blood, bronchoalveolar lavage fluid, and lung homogenate were used as the template DNA. Primers were synthetic oligonucleotides among 16s rDNA sequences. All of the primer combinations gave PCR products, but the primer pair of #24 and #27 gave best quality product of 666 bp. The sensitivity of PCR with lysates of BAL fluid was 57.7% but it increased to 84.6% with extracted DNAs. None of BAL lysate or DNA was positive among 13 microscopically negatives. The serum DNAs were positive only in 2 cases out of 20 morphologically positive rats. DNAs of human, rat, other parasites, yeast, and microorganisms were negative. The findings suggest that the present primers are specific but simple lysate of BAL fluid is not sensitive. PCR may be used as a routine diagnostic method of pneumocystosis if simple and rapid preparation of non-invasive clinical specimens are available.

Hormonal analysis in the diagnosis of thyroid diseases: A lecture

The creation of methods of radioimmunological analysis (RIA) to determine hormones had a decisive influence on the development of modern endocrinology and especially thyroidology. Since 1973, RIA methods have become routine diagnostic methods for the determination of thyroxine (T4), triiodothyronine (T3) and thyroid stimulating hormone (TSH). However, for a long time they made it possible to determine only the fractions of hormones associated with transport proteins, and RIA methods for determining TSH did not allow to determine its low (< 0.1 Mme/l) concentrations. Later, variants of RIA were developed based on the immunometric principle, using solid-phase carriers and monoclonal antibodies. This made it possible to determine, along with the general T4 and T3, also their free forms. Namely free T4 and T3 (FT4 and FT3) provide the entire spectrum of biological activity. Their definition is the most informative in assessing the functional state of the hypothalamus-pituitary-thyroid gland. The IRMA principle allowed to increase the sensitivity of the method for determining TSH to 0.16 mIU/L. This level of sensitivity satisfied clinicians in assessing the euthyroid state and hypothyroidism, but it did not allow to differentiate the normal level of TSH from subnormal in patients with thyrotoxicosis. In the last decade, fundamentally new non-isotopic technologies of hormonal immunoassay have been created. The sensitivity of this method in determining TSH was brought to 0.03 mIU/L. Currently, the determination of FT4 and TSH using the hypersensitive method is a strategic diagnostic approach to assessing the hormonal status of the thyroid gland.

Untersuchungen zum Antikörperstatus von Wild‐ und Zoovögeln gegen ausgewählte Nutztier‐relevante Erreger

Serum samples from wild birds of 21 species were investigated for antibodies against a broad range of pathogenic microorganisms. Using routine diagnostic methods, antibodies against a choice of relevant viral and bacterial agents were detected. The epidemiology and the significance of infections in both wild birds and farm poultry are discussed.

Diagnostic Medical Parasitology

Section 1. Philosophy and Approach to Diagnostic Parasitology Why Perform This Type of Testing? Who Should Perform Diagnostic Parasitology Testing? Where Should Diagnostic Parasitology Testing Be Performed? What Factors Should Precipitate Testing? What Testing Should Be Performed? What Factors Should Be Considered When Developing Test Menus?Section 2. Parasite Classification and Relevant Body Sites Protozoa Nematodes Cestodes Trematodes Pentastomids AcanthocephalaSection 3. Collection Options Safety Collection of Fresh Stool Specimens Preservation of Stool Specimens Collection of Blood Collection of Specimens from Other Body SitesSection 4. Specimen Test Options: Routine Diagnostic Methods and Body Sites O&P Examination of Stool Specimens Other Diagnostic Methods for Stool Specimens Testing of Other Intestinal Tract Specimens Urogenital Tract Specimens Sputum Aspirates Biopsy Specimens Blood Culture Methods Animal Inoculation and Xenodiagnosis Antigen and Antibody DetectionSection 5. Specific Test Procedures and Algorithms Microscopy O&P Examination Specialized Stains for Coccidia and Microsporidia Larval Nematode Culture Other Methods for Gastrointestinal Tract Specimens Methods for Urogenital Tract Specimens Preparation of Blood Films Blood ConcentrationSection 6. Commonly Asked Questions about Diagnostic Parasitology Specimen Collection Specimen Processing Diagnostic Methods Organism Identification Reporting Proficiency TestingSection 7. Parasite Identification Protozoa Nematodes Cestodes TrematodesSection 8. Identification Aids

Chronic refractory diarrhoea: a manifestation of endocrine disorders.

Hormonally mediated chronic refractory diarrhoeas constitute a rare but important group which often defy precise diagnosis when conventional routine diagnostic methods are used. Hormonal diarrhoea may occur in carcinoid syndrome, medullary carcinoma of the thyroid, thyrotoxicosis, gastrinoma, VIPoma, glucagonoma, somatostatinoma and systemic mastocytosis. Diagnosis of these conditions depends upon the awareness of clinicians, on clinical features and on documentations of high circulating hormones, if required, by using provocative tests. Precise localization of the tumours may be accomplished by ultrasonography, computerised axial tomography, angiography, percutaneous transhepatic portal and pancreatic venous sampling for the estimation of hormone concentrations. Benign tumours are removed surgically. Malignant neoplasms are treated either by surgery or chemotherapy depending upon the progress of the disease. Diarrhoea usually ceases when hormone levels are normalized following successful treatment.

Spectrum of differentiation in pediatric epithelial tumors of kidney: Report of two cases

Two unusual presentations of childhood renal cell epithelial tumors including one whose unique clinical manifestation was polycythemia are described. One was a renal cell carcinoma which was so poorly differentiated that ancillary histopathologic techniques were necessary to arrive at the correct diagnosis. The other case represented the opposite extreme being so well-differentiated as to raise the differential diagnosis of renal cell carcinoma versus renal cell adenoma with blastemal areas. These case studies exemplify the practical role for specialized histopathologic techniques in diagnosing pediatric renal tumors, which may not be feasibly or even accurately categorized into known renal tumor types using routine diagnostic methods.

Comparison of polymerase chain reaction with virus isolation and haemagglutination assays for the detection of canine parvoviruses in faecal specimens

A polymerase chain reaction ( PCR) assay, which specifically amplifies the capsid gene of canine parvovirus ( CPV), was compared as a diagnostic method for detecting CPV in faeces, with virus isolation ( VI) on Crandell feline kidney ( CRFK) or Madin-Darby canine kidney ( MDCK) cells, and a faecal haemagglutination ( HA) assay confirmed by inhibition with a CPV-specific antiserum. Although a false-negative result was obtained in one of 59 faecal samples (1·7 per cent) tested by the PCR assay, it was as sensitive as the VI assay using MDCK cells, and more sensitive than the VI assay using CRFK cells or the HA assay. These results indicate that the PCR assay may be useful as a routine diagnostic method for detecting CPV in faecal specimens.

High-resolution cardiac SPET study using fanbeam collimators in infants

High-resolution three-headed single photon emission computed tomography (SPET) equipped with fan-beam collimators was applied to myocardial perfusion imaging in infants aged from 1 to 11 months (n = 5). A tabletop designed specifically for infants was fixed on the SPET couch to reduce the radius of camera rotation to 13.2 cm. Significant improvement in resolution was achieved with the fan-beam collimators compared to parallel-hole high-resolution collimators. With the administration of approximately 37 MBq (26-44 MBq) 201Tl, 5 min acquisition time was possible for SPET imaging, which provided good image quality in all patients. Thus, a smaller administration dose is possible within a practical short acquisition time. High-resolution fan-beam SPET imaging can be a routine diagnostic method for heart disease in newborn babies and infants.

Chronic Wrist Pain

Chronic wrist pain is among the most difficult diagnostic and therapeutic challenges faced by hand surgeons. The causes are often elusive, of long duration, and not uncovered easily by routine diagnostic methods. This article outlines a systematic evaluation of the patient with chronic wrist pain to determine which of many potential conditions is the cause of the wrist pain so an effective therapeutic plan can be formulated.