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PubMed2002

Tests of glycemia for the diagnosis of type 2 diabetes mellitus.

This paper discusses tests of glycemia for the diagnosis of type 2 diabetes mellitus, with particular reference to the 1997 diagnostic criteria of the American Diabetes Association. The potential benefits of the lower diagnostic threshold for fasting plasma glucose are not well defined. However, the change in the diagnostic cut-off for diabetes mellitus affects as many as 1.9 million persons in the United States; therefore, the medical and social costs of the lower threshold may be considerable. Type 2 diabetes mellitus is defined by a threshold imposed on the continuous distribution of glycemic levels, typically with respect to risk for microvascular complications. However, the burden of type 2 diabetes relates more to macrovascular than microvascular complications. Because no clear threshold exists for macrovascular complications, a formal balancing of direct and indirect costs with both microvascular and macrovascular complications may be appropriate to establish glycemic thresholds. Because fasting plasma glucose, hemoglobin A1c, and the oral glucose tolerance test all predict diabetic complications yet test reliability is better for fasting plasma glucose and hemoglobin A1c than for the oral glucose tolerance test, we suggest an alternative diagnostic approach: If random plasma glucose is elevated (> or =11.1 mmol/L [200 mg/dL]) and the hemoglobin A1c level is more than 2 SDs above the laboratory mean, then diabetes mellitus should be diagnosed, and management should be based on the hemoglobin A1c level. If the result of only one of these tests is positive, then fasting plasma glucose should be tested to evaluate the patient for impaired fasting glucose and diabetes mellitus. The glycemic threshold for type 2 diabetes should be established by cost-effectiveness analysis. The clinical diagnosis of diabetes mellitus could be streamlined by incorporation of hemoglobin A1c into established criteria.

Adult↗
PubMed2005

Masked hypertension assessed by ambulatory blood pressure versus home blood pressure monitoring: is it the same phenomenon?

BACKGROUND: Masked hypertension is defined as normal clinic blood pressure (CBP) and elevated out-of-clinic blood pressure assessed using either self-monitoring of blood pressure (BP) by the patients at home (HBP) or ambulatory BP (ABP) monitoring. This study investigated the level of agreement between ABP and HBP in the diagnosis of masked hypertension. METHODS: Participants referred to an outpatient hypertension clinic had measurements of CBP (two visits), HBP (4 days), and ABP (24 h). The diagnosis of masked hypertension based on HBP (CBP <140/90 mm Hg and HBP > or =135/85) versus ABP (CBP <140/90 and awake ABP > or =135/85) was compared. RESULTS: A total of 438 subjects were included (mean age +/- SD, 51.5 +/- 11.6 years; 59% men and 41% women, 34% treated and 66% untreated). Similar proportions of subjects with masked hypertension were diagnosed by ABP (14.2%) and HBP (11.9%). In both treated and untreated subjects, the masked hypertension phenomenon was as common as the white coat phenomenon. Among 132 subjects with normal CBP, there was disagreement in the diagnosis of masked hypertension between the HBP and the ABP method in 23% of subjects for systolic and 30% for diastolic BP (kappa 0.56). When a 5-mm Hg gray zone for uncertain diagnosis was applied to the diagnostic threshold, the disagreement was reduced to 9% and 6% respectively. CONCLUSIONS: Similar proportions of subjects with masked hypertension are detected by ABP and HBP monitoring. Although disagreement in the diagnosis between the two methods is not uncommon, in the majority of these cases the deviation of the diagnostic BP above the threshold in not clinically important. Both ABP and HBP monitoring appear to be appropriate methods for the detection of masked hypertension.

Blood Pressure↗
PubMed1995

Comparison of diagnostic specimens and methods to evaluate infected venous access ports.

BACKGROUND: Implanted venous access port infection can be difficult to diagnose and treat. If device removal is necessary, confirming port infection is problematic. MATERIALS AND METHODS: Culture specimens from three sites, catheter tip (Tip), port pocket, and the material within the reservoir (Inside), were sent from ports removed for potential infection. The results of these cultures were compared to preremoval peripheral and central blood cultures. RESULTS: Forty-five ports were removed for suspected infection. Confirmed port infection was defined as positive culture(s) from one or more experimental specimen(s). In 29 evaluable cases, the Inside specimens were completely predictive. Tip specimens were less accurate, even with a lower diagnostic threshold. In 7 of 19 confirmed infections, only the Inside culture was diagnostic. CONCLUSION: The most predictive culture specimen in a potentially infected port is the thrombotic material inside the reservoir.

Adult↗
PubMed1999

Typologies of anxiety, depression and somatization symptoms among primary care attenders with no formal mental disorder.

BACKGROUND: Typologies of anxiety, depression and somatization symptoms were investigated in individuals with no formal mental disorders, making no a priori assumptions about symptom distribution and inter-relationship. METHOD: The subjects were 1617 adult primary care attenders from the WHO Collaborative Project on Psychological Problems in General Health Care, with at least three symptoms of anxiety, depression and/or somatization, but with no formal ICD-10 disorders. Analyses were based on the grade of membership model, a multivariate statistical procedure exploring indistinct boundaries between disease categories and preserving the heterogeneity of clinical picture within each category. RESULTS: Six prototype categories (or pure types) best described the structure of symptoms included in analyses. Pure type I included the full set of somatization symptoms. Pure type II was characterized by most anxiety and depression symptoms. Pure type III resembled generalized anxiety disorder. Pure type IV consisted of individuals reporting sporadic symptoms of anxiety, depression or somatization. Pure type V defined individuals with sleep problems. Finally, pure type VI was characterized by anxiety symptoms, including panic-like symptoms. CONCLUSIONS: These findings provide support to the existence of a mixed anxiety-depression category crossing the diagnostic boundaries of current anxiety and depression disorders. Moreover, criteria of anxiety and somatization disorders may be re-examined to assess whether lower diagnostic thresholds can be identified that both preserve the symptom profile and clinical features of current diagnostic categories and allow for a better characterization of individuals with substantial psychopathology though not meeting the high symptom thresholds required for a diagnosis of formal mental disorders.

Adolescent↗
PubMed2001

Tc 99m-Sestamibi scintimammography in the differentiation of benign and malignant breast microcalcifications.

The capability of the mammography-scintimammography combination to distinguish between benign and malignant isolated clusters of breast microcalcifications is discussed. Scintimammography using Tc 99m-Sestamibi was performed in 97 women with an isolated cluster of microcalcifications on mammograms. Seventy-two women had final histopathologic diagnoses (24 cancer and 48 benign pathology). The other 25 patients had follow-up to 3 years. The results of mammography, scintimammography and mammography-scintimammography combination were divided into five groups, based on the suspicion of malignancy. The sensitivity, specificity, false negative fraction, false positive fraction, predictive positive value, predictive negative value and diagnostic accuracy were calculated varying the diagnostic threshold. The Receiver Operating Characteristic (ROC) statistical technique was employed to compare the diagnostic value of mammography to mammography-scintimammography combination. The area under the ROC curves was calculated by the Wilcoxon statistic without any hypothesis on data distribution. The detected difference between areas under the mammography ROC curve (area=0.854, standard error=0.049) and mammography-scintimammography ROC curve (area=0.897, standard error 0.033) was statistically significant (P>0.05, one tail). The area under a ROC curve represents the probability that a randomly chosen diseased or non-diseased subject could be correctly classified. From this point of view this paper demonstrates that, if properly used, scintimammography can add to mammography in the characterization of an isolated cluster of microcalcifications, even if it is not able to replace FNAB and core biopsy.

Journal Article↗
PubMed2006

Atypical small acinar proliferation in the prostate: clinical significance in 2006.

About 2% of contemporary prostate needle biopsy specimens contain collections of small acini that are suspicious for cancer but that fall below the diagnostic threshold and are reported as atypical small acinar proliferation suspicious for but not diagnostic of malignancy. Prostate cancer has been identified in specimens from subsequent biopsies in up to 60% of cases of atypical small acinar proliferation, indicating that this finding is a significant predictor of cancer. Identification of atypical small acinar proliferation warrants repeat biopsy for concurrent or subsequent invasive carcinoma.

Adenocarcinoma↗
PubMed1996

A comparison of DSM-III-R and ICD-10 personality disorder criteria in an out-patient population.

This study reports the results of a comparison of DSM-III-R and ICD-10 personality disorder criteria by application of both sets of criteria to the same group of patients. Despite the clinical relevance of these disorders and the need for reliable diagnostic criteria, such a comparison has not previously been reported. DSM-III-R and ICD-10 have converged in their classification of personality disorders, but some important differences between the two systems remain. Personality disorder diagnoses from both systems were obtained in 52 out-patients, using the Standardized Assessment of Personality (SAP), a brief, informant-based interview which yields diagnoses in both DSM-III-R and ICD-10. For individual personality disorder diagnoses, agreement between systems was limited. Thirty-four subjects received a personality disorder diagnosis that had an equivalent form in both systems, but only 10 subjects (29%) received the same primary diagnosis in each system. There was a difference in rate of diagnosis, with ICD-10 making significantly more personality disorder diagnoses. The lower diagnostic threshold of the ICD-10 contributed most of this effect. Further modifications in ICD-10 Diagnostic Criteria for Research (DCR) and DSM-IV to the personality disorder category have been considered. The omission in DSM-IV of three categories unique to that system and the raising of the threshold in ICD-10 DCR, do seem to have been helpful in promoting convergence.

Adolescent↗
PubMed2003

[Transcranial color Doppler sonography (TCCD) in the diagnosis of vasospasm in the middle cerebral artery. Evaluation of TCCD diagnostic effectiveness by means of receiver operating characteristics curve (ROC) analysis].

Transcranial Doppler sonography is commonly used for diagnosis of cerebral vasospasm. However, the overall diagnostic performance of this method in detection of arterial narrowing has not been established. Blood velocity threshold, diagnostic for vasospasm, has been proposed for conventional, "blind" transcranial Doppler sonography (TCD). Nevertheless it cannot be used for transcranial color Doppler sonography (TCCD), because in this method the obtained blood velocities in the major cerebral arteries are higher than are in TCD. The aim of this study was to estimate the accuracy of transcranial color Doppler sonography in detection of middle cerebral artery (MCA) narrowing by means of receiver operating characteristic curve analysis (ROC). One hundred thirty four patients were studied with TCCD immediately before cerebral angiography. There were 75 men and 59 women, age range from 18 to 74 years, mean age 49 years. Of the 268 MCAs examined, 227 arteries were finally included in the construction of the ROC curve. Angiographic vasospasm was graded as none, mild (equal to or less than 25% of vessel caliber reduction--16 patients) and moderate-to-severe (more than 25% of vessel caliber reduction--29 patients). The overall diagnostic performance of transcranial color Doppler sonography in the detection of moderate-to-severe vasospasm of middle cerebral artery was found to be very high. The value of associated area under the ROC curve was 0.94. The value of this area for all vasospasms was 0.85, and this indicates good accuracy of a test. The best performing TCCD parameter for the detection of MCA narrowing was revealed to be peak-systolic velocity. The optimal trade-off between sensitivity and specificity was achieved with a peak systolic velocity of 182 cm/s. Therefore this velocity threshold is proposed as most universal for the diagnosis of vasospasm in the middle cerebral artery.

Adolescent↗
PubMed1998

The epidemiology and classification of bulimia nervosa.

BACKGROUND: We sought to determine whether there was empirical support for the diagnostic thresholds of DSM-IV bulimia nervosa (BN) and whether an empirically derived typology resembled the diagnostic categories of DSM-IV. METHODS: Detailed information about bulimic behaviours were assessed via personal interview in a population-based sample of 1897 Caucasian female twins. We assessed the lifetime prevalence of the component bulimic behaviours and DSM-IV and DSM-III-R BN. Latent class analysis of nine separate bulimic symptoms was used to develop an empirical typology of bulimic behaviour. RESULTS: Although the lifetime prevalences of bingeing (23.6%) and vomiting (4.8%) were relatively common, DSM-IV BN was distinctly uncommon (0.5%). The criterion that specified the frequency and duration of bingeing and vomiting was an important limiting condition. Analysis of alternative thresholds found little support for the DSM-IV thresholds requiring an average of twice per week for 3 months. Latent class analysis yielded an interpretable four class solution that had little overlap with the DSM-IV typology. CONCLUSIONS: As in other studies of unselected samples of women, the lifetime presence of bulimic behaviours are relatively high. Our results suggest that the DSM-IV approach to categorizing bulimic behaviour inadequately captures the spectrum of lifetime bulimic behaviours in the general population.

Adult↗
PubMed2002

Quantitative culture of endotracheal aspirates in the diagnosis of ventilator-associated pneumonia in patients with treatment failure.

STUDY OBJECTIVE: To study the correlation of bacteriology between quantitative cultures of protected specimen brush (PSB), BAL, and quantitative endotracheal aspirate (QEA) in ventilator-associated pneumonia (VAP) patients with treatment failure. DESIGN: Prospective observational clinical study. SETTING: A 15-bed medical ICU of tertiary medical center. PATIENTS: Forty-eight patients receiving mechanical ventilation with clinical suspected VAP who had been treated with antibiotics for at least 72 h without improvement. INTERVENTION: QEA, PSB, and BAL were performed with patients receiving antibiotics. The diagnostic thresholds for QEA, PSB, and BAL were 10(5), 10(3), and 10(4) cfu/mL, respectively. MEASUREMENTS AND RESULTS: Microbial culture findings were positive in 24 BAL samples (50%), in 23 PSB samples (48%), and in 28 QEA samples (58%). The correlations between of QEA vs PSB and QEA vs BAL were significant (rho = 0.567 and rho = 0.620, p < 0.01, respectively). The most commonly isolated microorganisms were Acinetobacter baumannii (27%), Staphylococcus aureus (24%), Stenotrophomonas maltophilia (15%), and Pseudomonas aeruginosa (10%). Using the predetermined criteria, bacterial pneumonia was diagnosed in 28 of 48 suspected VAP episodes based on PSB and/or BAL results. The diagnostic efficiency of QEA at threshold of 10(5) cfu/mL had a sensitivity of 92.8% and a specificity of 80%. CONCLUSIONS: QEA correlated with PSB and BAL in patients with suspected VAP who responded poorly to the existent antibiotic treatment. QEA missed only two cases of bacterial pneumonia diagnosed by invasive PSB and/or BAL with acceptable sensitivity and specificity. More importantly, QEA is noninvasive and easily repeatable. Early use of QEA is helpful to clinical physicians in decision making with regard to antibiotics use.

Aged↗
PubMed1996

Measurement of human cytomegalovirus-associated DNA polymerase activity in patient urine as a potential diagnostic tool.

Virus-associated DNA polymerase activity has recently been proposed for the detection of human cytomegalovirus (HCMV) in urine, a method that should allow rapid and quantitative determination of the viral load. In this report, the virus-associated DNA polymerase activity recovered from the urine of a group of patients shedding HCMV was measured using a poly(dA) oligo(dT) 12-18 synthetic template after polyethylene glycol precipitation of the virions. Detection of virus-associated DNA polymerase activity was compared to the classical methods most widely used to diagnose HCMV shedding in urines such as virus culture followed by indirect immunofluorescence and pp65 gene-specific polymerase chain reaction. Although less sensitive than the polymerase chain reaction and cross-reactive with other herpesvirus DNA polymerases, the activity measured in the urine samples was correlated with the number of positive nuclei found in shell vials (r = 0.89). The diagnostic threshold of the assay could be placed between 50 and 100 fluorescent nuclei per shell with a diagnostic sensitivity of 56%. Being simple and quantitative, the measurement of virus-associated DNA polymerase activity could be of value in some clinical conditions where it is necessary to assess viral load in urine. This method is proposed as an alternative to more laborious quantitative assays and to support qualitative polymerase chain reaction.

Animals↗
PubMed1996

Stages in the recognition of epidemic pellagra in the United States: 1865-1960.

Recognition of the U.S. pellagra "epidemic" in the early part of this century occurred in stages. The recognition process distorted impressions of magnitude, rate of spread, and virulence. Unrecognized cases: Endemic pellagra developed from dietary deficiencies after the Civil War. Initially, cases were misdiagnosed as other more traditional disorders. Tradition and authority inhibited recognition. Recognition of severe cases: Beginning in 1907, outbreaks were reported in asylums. Existing severe cases came rapidly to medical attention, inflating the apparent rate of spread. Recognized cases had a fulminant course and a high case fatality. Expanded spectrum: Milder cases were increasingly recognized, leading to an exaggerated rate of increase in number of cases and a decrease in case fatality and apparent virulence. Greater sensitivity resulted largely from a shift in diagnostic thresholds, with loss of specificity and increase in false positive diagnoses. Standardization of diagnosis: Although no suitable diagnostic marker test was developed, diagnosis was ultimately standardized by development of a workable case definition and by assessment of response to an effective therapy (nicotinic acid) applied to presumptive cases.

Disease Outbreaks↗
PubMed1993

Prevalence and stability of the DSM-III-R personality disorders in a community-based survey of adolescents.

OBJECTIVE: The purpose of this study was to estimate the prevalence, concurrent validity, and stability of DSM-III-R personality disorders in a large community-based sample of adolescents. METHOD: A randomly selected community sample of 733 youths ranging in age from 9 to 19 years was followed over a 2-year period. The protocol consisted of structured interviews with the adolescents and their mothers and self-report questionnaires. Algorithms for 10 DSM-III-R axis II disorders were developed to produce diagnoses at two levels of severity; these were validated against multiple indicators of distress and functional impairment. RESULTS: The overall prevalence of personality disorders peaked at age 12 in boys and at age 13 in girls and declined thereafter. Obsessive-compulsive personality disorder was the most prevalent moderate axis II disorder, narcissistic personality disorder the most prevalent severe disorder, and schizotypal personality disorder the least prevalent axis II disorder, based on both moderate and severe diagnostic thresholds. All moderate axis II disorders were associated with significantly greater odds for at least five of 12 diagnostic validators. Longitudinal follow-up revealed that although most axis II disorders did not persist over a 2-year period, subjects with disorders identified earlier remained at elevated risk for receiving a diagnosis again at follow-up. CONCLUSIONS: These findings suggest that a substantial minority of adolescents who are not in treatment qualify for DSM-III-R personality disorder diagnoses and that these diagnoses are associated with increased risk of psychological distress and functional impairment.

Adolescent↗
PubMedDate not supplied

Prevalence of dental caries in Latvian 11- to 15-year-Old children and the enhanced diagnostic yield of temporary tooth separation, FOTI and electronic caries measurement.

The aim of this study was to test the feasibility of employing clinical visual examination at the D(1) (enamel and dentine caries) diagnostic threshold, fibre-optic transillumination (FOTI), elective temporary tooth separation (ETTS) and electronic caries measurement (ECM) in the environment of an epidemiological study or clinical trial. It also aimed to compare the diagnostic yield of these diagnostic aides and methods. The sample consisted of 182 Latvian children, mean age 13.3 years (range = 10.6-15.7). For 12-year-old subjects the mean D(3)MFS was 10.58 (SD 6.05) and the mean D(1)MFS was 19.97 (SD 10.47). The additional diagnostic yield from FOTI examination of approximal sites was 40.0% at the D(1) threshold. The additional apparent yield for ETTS was 52.8% at the D(1) threshold. ETTS detected 38.3% more carious surfaces than FOTI at the D(1) threshold. Conversely 57 surfaces thought to be carious on FOTI examination were judged sound following ETTS. Although the ECM appeared practical to use, it broke early in the trial and the results obtained prior to breakdown appeared inaccurate. In conclusion, all diagnostic methods were feasible under the conditions of an epidemiological study or clinical trial.

Adolescent↗
PubMed2006

Measuring and estimating diagnostic accuracy when there are three ordinal diagnostic groups.

This article studies the problem of measuring and estimating the diagnostic accuracy when there are three ordinal diagnostic groups. We use a receiver operating characteristic (ROC) surface to describe the probabilities of correct classifications into three diagnostic groups based on various sets of diagnostic thresholds of a test and propose to use the entire and the partial volume under the surface to measure the diagnostic accuracy. Mathematical properties and probabilistic interpretations of the proposed measure of diagnostic accuracy are discussed. Under the assumption of normal distributions of the diagnostic test from three diagnostic groups, we present the maximum likelihood estimate to the volume under the ROC surface and give the asymptotic variance to the estimate. We further propose several asymptotic confidence interval estimates to the volume under the ROC surface. The performance of these confidence interval estimates is evaluated in terms of attaining the nominal coverage probability based on a simulation study. In addition, we develop a method of sample size determination to achieve an adequate accuracy of the confidence interval estimate. Finally, we demonstrate the proposed methodology by applying it to the clinical diagnosis of early stage Alzheimer's disease based on the neuropsychological database of the Washington University Alzheimer's Disease Research Center.

Alzheimer Disease↗
PubMed1985

Measuring and interpreting increases in probing depth and attachment loss.

Increases in probing depth and attachment level measurements are used by clinicians and clinical scientists for assessing the periodontal status and/or change in status of patients. Interpretation of these measurements has implications with respect to our understanding of periodontal disease, treatment of patients and the implementation of clinical investigations. Measurements of probing depths and attachment loss were made on 204 teeth in 34 patients. The measurements were repeated after short periods of time by different examiners as well as the same examiners. Using these data, sensitivities and specificities of several potential diagnostic thresholds were calculated. It is concluded that observing an increase of probing depth greater than 1 mm serves as a diagnostic test with high sensitivity and specificity.

Epithelial Attachment↗
PubMed1994

DSM-IV field trials for attention deficit hyperactivity disorder in children and adolescents.

OBJECTIVE: Optimal diagnostic thresholds were determined for DSM-IV attention deficit hyperactivity disorder, and the psychometric properties were compared to alternative definitions. METHOD: Structured diagnostic interviews of multiple informants for 380 clinic-referred youths aged 4-17 years were conducted. In addition, standardized clinicians' validation diagnoses of attention deficit disorder were obtained to assess agreement with clinical judgment. Measures of impairment were obtained to assess the accuracy of identifying youth with an impairing condition. RESULTS: Three subtypes of attention deficit hyperactivity disorder (predominantly inattentive, predominantly hyperactive-impulsive, and combined types) were distinguished on the basis of the degree of deviance on separate dimensions of inattention and hyperactivity-impulsivity. These three subtypes were found to differ in terms of types of impairment, age, and sex ratio, but not ethnicity. In terms of case identification of attention deficit hyperactivity disorder, DSM-IV was found to be very similar to DSM-III-R, except that DSM-IV identified more impaired girls and preschool children. CONCLUSIONS: These results support the decision to subdivide the heterogeneous category of DSM-III-R attention deficit hyperactivity disorder into three subtypes. The resulting DSM-IV definition appears to be somewhat less biased toward the symptom pattern typical of elementary school boys.

Adolescent↗