Diagnostic Specificity (diagnostic + specificity)

Distribution by Scientific Domains
Distribution within Medical Sciences

Selected Abstracts

Prefrontal gyral folding and its cognitive correlates in bipolar disorder and schizophrenia

A. M. McIntosh
Objective:, We sought to address whether dorsal or ventral prefrontal gyrification is abnormal in bipolar disorder and to determine its diagnostic specificity and cognitive associations. Method:, Forty-two out-patients with bipolar disorder, 28 with schizophrenia and 37 controls underwent magnetic resonance imaging. All subjects also underwent IQ and executive assessments using tasks whose performance has been localized to the ventral or dorsal prefrontal cortex. Cortical folding was quantified using the gyrification index (GI) and related to the cognitive measures. Results:, Patients with bipolar disorder showed reduced prefrontal gyrification compared with controls but did not differ from patients with schizophrenia. Neither ventral nor dorsal GI was preferentially affected in either disorder. Current IQ was positively and significantly correlated with GI. Conclusion:, Patients with bipolar disorder and patients with schizophrenia have reduced prefrontal gyrification affecting both ventral and dorsal subregions. These reductions were significantly associated with cognitive impairments occurring in both disorders. [source]

Differential diagnostic features of small cell carcinoma in the uterine cervix

Min Jung Kim M.D.
Abstract Small cell carcinoma (SMCC) of the uterine cervix is rare and known to be an aggressive tumor, but there are only few reports on the cytologic features of cervical SMCC. This rare small cell lesion should be distinguished from malignant lymphoma (ML), squamous cell carcinoma in situ (SCIS), and chronic lymphocytic cervicitis (CLC). By clarifying cytologic features and reevaluating the significance of cervical cytologic smears to reveal these cervical lesions, we can improve the diagnostic specificity and patient's outcome. The clinical record and available cervical smears from 13 cases of SMCC, four cases of malignant lymphoma, 20 cases of SCIS, and five cases of CLC were analyzed. The cytologic differential diagnostic points of SMCC were nuclear molding and smearing (100%), salt and pepper chromatin (100%), exudative and necrotic background (91.7%), various architectures including individual cells (83.3%), tight clusters (75%) and feathering and strip (50%), and inconspicuous nucleoli (75%). Early diagnosis of the cervical SMCC by cytology and treatment is important for better outcome of patients. Diagn. Cytopathol. 2008;36:618,623. © 2008 Wiley-Liss, Inc. [source]

Are adjunctive markers useful in routine cervical cancer screening?

Application of p16INK4a, HPV-PCR on ThinPrep samples with histological follow-up
Abstract The objectives of the study were to evaluate 1) the diagnostic sensitivity and specificity of p16INK4a as a marker for high-grade cervical lesions, 2) the results of a real-time polymerase chain reaction detecting high-risk human papillomavirus, and 3) the interobserver variability of the p16INK4a interpretation. A total of 232 ThinPrep samples were stained for p16INK4a, and HPV-DNA PCR was performed on 107 specimens with inclusion of both benign and abnormal cytology. Histological follow-up information was collected. The diagnostic sensitivity of ASC+ with CIN2+ in histology as endpoint was 96% for p16INK4a and 100% for HR-HPV DNA PCR, and the diagnostic specificity was 41% and 27%, respectively. If p16INK4a had been used for triage of the ASC samples, then 18 patients (42%) could have been spared unnecessary follow-up procedures compared to six patients (21%) with the HR-HPV DNA test. Diagn. Cytopathol. 2008;36:453,459. © 2008 Wiley-Liss, Inc. [source]

Comparison of different methods of bacterial detection in blood components

M. Schmidt
Background, Over the last two decades, the residual risk of acquiring a transfusion-transmitted viral infection has been reduced to less than 1 : 1 000 000 via improvements in different techniques (e.g. donor selection, leuco-depletion, introduction of 3rd or 4th generation enzyme-linked immunosorbent assays and mini-pool nucleic acid testing (MP-NAT). In contrast, the risk for transfusion-associated bacterial infections has remained fairly stable, and is estimated to be in a range between 1 : 2000 and 1 : 3000. Platelets are at an especially higher risk for bacterial contamination, because they are stored at room temperature, which provides good culture conditions for a broad range of bacterial strains. To improve bacterial safety of blood products, different detection systems have been developed that can be divided into culture systems like BacT/ALERT or Pall eBDS, rapid detection systems like NAT systems, immunoassays and systems based on the FACS technique. Culture systems are used for routine bacterial screening of platelets in many countries, whereas rapid detection systems so far are mainly used in experimental spiking studies. Nevertheless, pathogen-reduction systems are currently available for platelet concentrates and plasma, and are under investigation for erythrocytes. Methods, In this review, the functional principles of the different assays are described and discussed with regard to their analytical sensitivity, analytical specificity, diagnostic sensitivity, diagnostic specificity and clinical efficiency. The detection methods were clustered into three groups: (i) detection systems currently used for routine screening of blood products, (ii) experimental detection systems ready to use for routine screening of blood products, and (iii) new experimental detection systems that need to be investigated in additional spiking studies and clinical trials. Results, A recent International Society of Blood Transfusion international forum reported on bacterial detection methods in 12 countries. Eight countries have implemented BacT/ALERT into blood donor screening, whereas in three countries only quality controls were done by culture methods. In one country, shelf-life was reduced to 3 days, so no bacterial screening was implemented. Screening data with culture methods can be used to investigate the prevalence of bacterial contamination in platelets. Differing results between the countries could be explained by different test definitions and different test strategies. Nevertheless, false-negative results causing severe transfusion-related septic reactions have been reported all over the world due to a residual risk of sample errors. Rapid screening systems NAT and FACS assays have improved over the last few years and are now ready to be implemented in routine screening. Non-specific amplification in NAT can be prevented by pre-treatment with Sau3AI, filtration of NAT reagents, or reduction of the number of polymerase chain reaction cycles. FACS systems offer easy fully automated handling and a handling time of only 5 min, which could be an option for re-testing day-5 platelets. New screening approaches like immunoassays, detection of bacterial adenosine triphosphate, or detection of esterase activity need to be investigated in additional studies. Conclusion, Bacterial screening of blood products, especially platelets, can be done with a broad range of technologies. The ideal system should be able to detect one colony-forming unit per blood bag without a delay in the release process. Currently, we are far away from such an ideal screening system. Nevertheless, pathogen-inactivation systems are available, but a system for all blood components will not be expected in the next few years. Therefore, existing culture systems should be complemented by rapid systems like NAT or FACS especially for day-5 platelets. [source]

Recurrent autoimmune hepatitis after liver transplantation: Diagnostic criteria, risk factors, and outcome

Stefan G. Hübscher MD
Approximately 20% to 30% of patients undergoing liver transplantation for autoimmune hepatitis (AIH) develop features of recurrent disease. Diagnostic criteria for recurrent AIH are similar to those used in the nontransplanted liver and include, in varying combinations, biochemical, serological, and histological abnormalities and steroid dependency. However, these criteria are more difficult to apply in the liver allograft because of potential interactions between recurrent AIH and other complications of liver transplantation, particularly rejection, and the uncertain effects of long-term immunosuppression. In the absence of other reliable diagnostic markers, a number of studies have used the histological finding of chronic hepatitis as the main or sole criterion for diagnosing recurrent AIH. However, this also lacks diagnostic specificity because there are many other possible causes of chronic hepatitis in the liver allograft. In addition, approximately 20% to 40% of biopsies performed on patients as part of routine annual review have histological features of chronic hepatitis, for which no definite cause can be identified. Risk factors that have been associated with the development of recurrent AIH include suboptimal immunosuppression, HLA phenotype, disease type and severity in the native liver, and duration of follow up. In many cases in which recurrent AIH seems to be related to underimmunosuppression, biochemical and histological features rapidly resolve once adequate immunosuppression is restored. However, in other cases, recurrent AIH behaves more aggressively, with progression to cirrhosis and graft failure. Areas that require further study include developing uniform criteria for the diagnosis of recurrent AIH, identifying risk factors for severe recurrent disease, and determining optimal levels of immunosuppression that minimize the impact of disease recurrence without exposing patients to the risks of overimmunosuppression. [source]

Ballooned neurones in the limbic lobe are associated with Alzheimer type pathology and lack diagnostic specificity

Y. Fujino
Ballooned neurones (BNs) are one of the pathological hallmarks of several neurodegenerative diseases, including Pick's disease, corticobasal degeneration and argyrophilic grain disease (AGD). They have also been described in Alzheimer disease (AD), but the frequency of BNs in AD has not been systematically addressed. In the present study, immunohistochemistry for ,B-crystallin was used as a sensitive method to detect BNs to determine the frequency of BNs in the limbic lobe in AD. At least a few BNs were detected in the limbic lobe of virtually all AD cases, and their density correlated with Braak stage, as well as the density of neurofibrillary tangles and senile plaques in the limbic lobe. The density of BN tended to be greater in AD cases with concurrent AGD than in pure AD. Given the high prevalence of AD in brain banks for neurodegenerative disease and the frequent presence of BNs in these areas with ,B-crystallin immunohistochemistry, the present findings further indicate that BNs confined to the limbic lobe lack specificity in diagnostic neuropathology. [source]

Evaluation of a rapid diagnostic field test kit for identification of Phytophthora species, including P. ramorum and P. kernoviae at the point of inspection

C. R. Lane
Plant health regulations to prevent the introduction and spread of Phytophthora ramorum and P. kernoviae require rapid, cost effective diagnostic methods for screening large numbers of plant samples at the time of inspection. Current on-site techniques require expensive equipment, considerable expertise and are not suited for plant health inspectors. Therefore, an extensive evaluation of a commercially available lateral flow device (LFD) for Phytophthora species was performed involving four separate trials and 634 samples. The assay proved simple to use, provided results in a few minutes and on every occasion a control line reacted positively confirming the validity of the test. LFD results were compared with those from testing a parallel sample, using laboratory methods (isolation and real-time PCR). The diagnostic sensitivity of the LFD (87·6%) compared favourably with the standard laboratory methods although the diagnostic specificity was not as stringent (82·9%). There were a small number (n = 28) of false negatives, but for statutory purposes where all positive samples must be identified to species level by laboratory testing, overall efficiency was 95·6% as compared with visual assessment of symptoms of between 20-30% for P. ramorum and P. kernoviae. This work demonstrates the value of the LFD for diagnosing Phytophthora species at the time of inspection and as a useful primary screen for selecting samples for laboratory testing to determine the species identification. [source]

Use of thymosin ,15 as a urinary biomarker in human prostate cancer

THE PROSTATE, Issue 2 2005
Lloyd M. Hutchinson
Abstract BACKGROUND Additional prostate cancer (CaP) biomarkers are needed to increase the accuracy of diagnosis and to identify patients at risk of recurrence. In tissue-based assays, thymosin ,15 (T,15) has been linked to an aggressive CaP phenotype and correlated with future tumor recurrence. We hypothesized that T,15 may have clinical utility in biological fluids. METHODS T,15 was measured in urine from CaP patients; untreated (N,=,61), prostatectomy (RP, N,=,46), androgen deprivation therapy (ADT, N,=,14) and control groups; normal (N,=,52), genitourinary carcinoma (N,=,15), non-malignant prostate disease (N,=,81), and other urology (N,=,73). We evaluated the utility of urinary T,15 for CaP diagnosis, alone or in combination with prostate-specific antigen (PSA), and the relationship to CaP progression. RESULTS A normal threshold of 40 (ng/dl)/(,g_protein/mg_creatinine) was defined using receiver operating characteristic analysis and marked the 19th centile for age-matched controls. The proportion of untreated CaP patients with urinary T,15 above the threshold was significantly higher than normal and genitourinary disease controls (P,<,0.001). RP caused urinary T,15 to drop significantly (P,=,0.005). Pre-surgery T,15 concentrations greater than the normal threshold may confer greater risk of CaP recurrence. Relative to normal controls, patients receiving ADT for aggressive CaP were 12 times more likely to have elevated urinary T,15 (P,=,0.001, 95% CI,=,2.8, 51.8). Combining PSA and T,15 (PSA,>,4, or PSA,>,2.5, T,15,>,40, or PSA,=,2.5, T,15,>,90) provided the same sensitivity as a 2.5 ng/ml PSA cutoff, but markedly improved diagnostic specificity. CONCLUSIONS We report that T,15 is a urinary biomarker for CaP and suggest that T,15, in combination with PSA, can be used to improve both the sensitivity and specificity of CaP diagnosis. © 2005 Wiley-Liss, Inc. [source]

White matter abnormalities in bipolar disorder and schizophrenia detected using diffusion tensor magnetic resonance imaging

Jessika E Sussmann
Objectives:, Strong qualitative and quantitative evidence exists of white matter abnormalities in both schizophrenia and bipolar disorder (BD). Diffusion tensor imaging (DTI) studies suggest altered connectivity in both disorders. We aim to address the diagnostic specificity of white matter abnormalities in these disorders. Methods:, DTI was used to assess white matter integrity in clinically stable patients with familial BD (n = 42) and familial schizophrenia (n = 28), and in controls (n = 38). Differences in fractional anisotropy (FA) were measured using voxel-based morphometry and automated region of interest analysis. Results:, Reduced FA was found in the anterior limb of the internal capsule (ALIC), anterior thalamic radiation (ATR), and in the region of the uncinate fasciculus in patients with BD and those with schizophrenia compared with controls. A direct comparison between patient groups found no significant differences in these regions. None of the findings were associated with psychotropic medication. Conclusions:, Reduced integrity of the ALIC, uncinate fasciculus, and ATR regions is common to both schizophrenia and BD. These results imply an overlap in white matter pathology, possibly relating to risk factors common to both disorders. [source]

Clinical decision-making using the General Behavior Inventory in juvenile bipolarity

Robert L Findling
Objective: The General Behavior Inventory (GBI) is a questionnaire that has utility in the assessment of mood disorders in adults. The purpose of this study was to examine how the GBI might optimally be used in the assessment of youths. Method: Children and adolescents between the ages of 5 and 17 years participated in this study. All youths were evaluated with the Schedule for Affective Disorders and Schizophrenia for School-Age Children (K-SADS). Based on the K-SADS results, subjects were then assigned to one of four groups: a bipolar spectrum group, a depressive disorders group, a disruptive behaviors disorders group, and a no diagnosis group. Guardians completed a version of the GBI modified for parent reporting. Patients 10 years old or greater also completed the GBI as a self-report measure. Results: There were 196 subjects who participated. Both parent report and youth self-report assigned patients to the appropriate diagnostic group with better than 74% accuracy. Combining information from multiple informants did not significantly improve diagnostic group assignment. Conclusions: These data suggest that the GBI may be a useful adjunct in the diagnosis of mood disorders in youths, particularly when diagnostic specificity is more important than sensitivity. [source]

Strategies for improving the diagnostic specificity of the frequency doubling perimeter

Govert P. Heeg
Abstract. Purpose:,To evaluate various strategies designed to improve the specificity of the interpretation of results obtained with the frequency doubling technology perimeter (FDT) used in the full-threshold mode. Methods:,Three different strategies were compared using data from 452 glaucoma patients and 237 healthy subjects: combining several FDT parameters from a single test, combining the FDT test with a GDx test, and confirming an abnormal FDT test result with a repeat test. Results:,Confirming an abnormal FDT test result with a repeat test yielded a specificity increase of 0.10, from 0.80 to 0.90, at the expense of some loss of sensitivity for early but not for moderate or severe glaucoma. Combining several FDT parameters from a single test and combining FDT with GDx did not yield any noticeable increase in diagnostic performance. Conclusions:,A modest increase in FDT diagnostic performance can be obtained by the confirmation of an abnormal test result with a repeat test. [source]