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At least 1,459 records · Page 81Linked to original sources
PubMed2005

Which diagnostic tests are most useful in a chest pain unit protocol?

BACKGROUND: The chest pain unit (CPU) provides rapid diagnostic assessment for patients with acute, undifferentiated chest pain, using a combination of electrocardiographic (ECG) recording, biochemical markers and provocative cardiac testing. We aimed to identify which elements of a CPU protocol were most diagnostically and prognostically useful. METHODS: The Northern General Hospital CPU uses 2-6 hours of serial ECG/ST segment monitoring, CK-MB(mass) on arrival and at least two hours later, troponin T at least six hours after worst pain and exercise treadmill testing. Data were prospectively collected over an eighteen-month period from patients managed on the CPU. Patients discharged after CPU assessment were invited to attend a follow-up appointment 72 hours later for ECG and troponin T measurement. Hospital records of all patients were reviewed to identify adverse cardiac events over the subsequent six months. Diagnostic accuracy of each test was estimated by calculating sensitivity and specificity for: 1) acute coronary syndrome (ACS) with clinical myocardial infarction and 2) ACS with myocyte necrosis. Prognostic value was estimated by calculating the relative risk of an adverse cardiac event following a positive result. RESULTS: Of the 706 patients, 30 (4.2%) were diagnosed as ACS with myocardial infarction, 30 (4.2%) as ACS with myocyte necrosis, and 32 (4.5%) suffered an adverse cardiac event. Sensitivities for ACS with myocardial infarction and myocyte necrosis respectively were: serial ECG/ST segment monitoring 33% and 23%; CK-MB(mass) 96% and 63%; troponin T (using 0.03 ng/ml threshold) 96% and 90%. The only test that added useful prognostic information was exercise treadmill testing (relative risk 6 for cardiac death, non-fatal myocardial infarction or arrhythmia over six months). CONCLUSION: Serial ECG/ST monitoring, as used in our protocol, adds little diagnostic or prognostic value in patients with a normal or non-diagnostic initial ECG. CK-MB(mass) can rule out ACS with clinical myocardial infarction but not myocyte necrosis(defined as a troponin elevation without myocardial infarction). Using a low threshold for positivity for troponin T improves sensitivity of this test for myocardial infarction and myocardial necrosis. Exercise treadmill testing predicts subsequent adverse cardiac events.

Journal Article↗
PubMed2006

Reproducibility of the STARD checklist: an instrument to assess the quality of reporting of diagnostic accuracy studies.

BACKGROUND: In January 2003, STAndards for the Reporting of Diagnostic accuracy studies (STARD) were published in a number of journals, to improve the quality of reporting in diagnostic accuracy studies. We designed a study to investigate the inter-assessment reproducibility, and intra- and inter-observer reproducibility of the items in the STARD statement. METHODS: Thirty-two diagnostic accuracy studies published in 2000 in medical journals with an impact factor of at least 4 were included. Two reviewers independently evaluated the quality of reporting of these studies using the 25 items of the STARD statement. A consensus evaluation was obtained by discussing and resolving disagreements between reviewers. Almost two years later, the same studies were evaluated by the same reviewers. For each item, percentages agreement and Cohen's kappa between first and second consensus assessments (inter-assessment) were calculated. Intraclass Correlation coefficients (ICC) were calculated to evaluate its reliability. RESULTS: The overall inter-assessment agreement for all items of the STARD statement was 85% (Cohen's kappa 0.70) and varied from 63% to 100% for individual items. The largest differences between the two assessments were found for the reporting of the rationale of the reference standard (kappa 0.37), number of included participants that underwent tests (kappa 0.28), distribution of the severity of the disease (kappa 0.23), a cross tabulation of the results of the index test by the results of the reference standard (kappa 0.33) and how indeterminate results, missing data and outliers were handled (kappa 0.25). Within and between reviewers, also large differences were observed for these items. The inter-assessment reliability of the STARD checklist was satisfactory (ICC = 0.79 [95% CI: 0.62 to 0.89]). CONCLUSION: Although the overall reproducibility of the quality of reporting on diagnostic accuracy studies using the STARD statement was found to be good, substantial disagreements were found for specific items. These disagreements were not so much caused by differences in interpretation of the items by the reviewers but rather by difficulties in assessing the reporting of these items due to lack of clarity within the articles. Including a flow diagram in all reports on diagnostic accuracy studies would be very helpful in reducing confusion between readers and among reviewers.

Advisory Committees↗
PubMed2003

Diagnostic properties of nerve conduction tests in population-based carpal tunnel syndrome.

BACKGROUND: Numerous nerve conduction tests are used for the electrodiagnosis of carpal tunnel syndrome (CTS), with a wide range of sensitivity and specificity reported for each test in clinical studies. The tests have not been assessed in population-based studies. Such information would be important when using electrodiagnosis in epidemiologic research. The purpose of this study was to compare the diagnostic accuracy of various nerve conduction tests in population-based CTS and determine the properties of the most accurate test. METHODS: In a population-based study a questionnaire was mailed to a random sample of 3,000 persons. Of 2,466 responders, 262 symptomatic (numbness/tingling in the radial fingers) and 125 randomly selected asymptomatic responders underwent clinical and electrophysiologic examinations. A standardized hand diagram was administered to the symptomatic persons. At the clinical examination, the examining surgeon identified 94 symptomatic persons as having clinically certain CTS. Nerve conduction tests were then performed on the symptomatic and the asymptomatic persons by blinded examiners. Analysis with receiver operating characteristic (ROC) curves was used to compare the diagnostic accuracy of the nerve conduction tests in distinguishing the persons with clinically certain CTS from the asymptomatic persons. RESULTS: No difference was shown in the diagnostic accuracy of median nerve distal motor latency, digit-wrist sensory latency, wrist-palm sensory conduction velocity, and wrist-palm/forearm sensory conduction velocity ratio (area under curve, 0.75-0.76). Median-ulnar digit-wrist sensory latency difference had a significantly higher diagnostic accuracy (area under curve, 0.80). Using the optimal cutoff value of 0.8 ms for abnormal sensory latency difference shown on the ROC curve the sensitivity was 70%, specificity 82%, positive predictive value 19% and negative predictive value 98%. Based on the clinical diagnosis among the symptomatic persons, the hand diagram (classified as classic/probable or possible/unlikely CTS) had high sensitivity but poor specificity. CONCLUSIONS: Using the clinical diagnosis of CTS as the criterion standard, nerve conduction tests had moderate sensitivity and specificity and a low positive predictive value in population-based CTS. Measurement of median-ulnar sensory latency difference had the highest diagnostic accuracy. The performance of nerve conduction tests in population-based CTS does not necessarily apply to their performance in clinical settings.

Adult↗
PubMed2003

The role of strategy and redundancy in diagnostic reasoning.

BACKGROUND: Diagnostic reasoning is a key competence of physicians. We explored the effects of knowledge, practice and additional clinical information on strategy, redundancy and accuracy of diagnosing a peripheral neurological defect in the hand based on sensory examination. METHOD: Using an interactive computer simulation that includes 21 unique cases with seven sensory loss patterns and either concordant, neutral or discordant textual information, 21 3rd year medical students, 21 6th year and 21 senior neurology residents each examined 15 cases over the course of one session. An additional 23 psychology students examined 24 cases over two sessions, 12 cases per session. Subjects also took a seven-item MCQ exam of seven classical patterns presented visually. RESULTS: Knowledge of sensory patterns and diagnostic accuracy are highly correlated within groups (R2 = 0.64). The total amount of information gathered for incorrect diagnoses is no lower than that for correct diagnoses. Residents require significantly fewer tests than either psychology or 6th year students, who in turn require fewer than the 3rd year students (p < 0.001). The diagnostic accuracy of subjects is affected both by level of training (p < 0.001) and concordance of clinical information (p < 0.001). For discordant cases, refutation testing occurs significantly in 6th year students (p < 0.001) and residents (p < 0.01), but not in psychology or 3rd year students. Conversely, there is a stable 55% excess of confirmatory testing, independent of training or concordance. CONCLUSIONS: Knowledge and practice are both important for diagnostic success. For complex diagnostic situations reasoning components employing redundancy seem more essential than those using strategy.

Diagnosis↗
PubMed2004

Overview of the diagnostic value of biochemical markers of liver fibrosis (FibroTest, HCV FibroSure) and necrosis (ActiTest) in patients with chronic hepatitis C.

SUMMARY: BACKGROUND: Recent studies strongly suggest that due to the limitations and risks of biopsy, as well as the improvement of the diagnostic accuracy of biochemical markers, liver biopsy should no longer be considered mandatory in patients with chronic hepatitis C. In 2001, FibroTest ActiTest (FT-AT), a panel of biochemical markers, was found to have high diagnostic value for fibrosis (FT range 0.00-1.00) and necroinflammatory histological activity (AT range 0.00-1.00). The aim was to summarize the diagnostic value of these tests from the scientific literature; to respond to frequently asked questions by performing original new analyses (including the range of diagnostic values, a comparison with other markers, the impact of genotype and viral load, and the diagnostic value in intermediate levels of injury); and to develop a system of conversion between the biochemical and biopsy estimates of liver injury. RESULTS: A total of 16 publications were identified. An integrated database was constructed using 1,570 individual data, to which applied analytical recommendations. The control group consisted of 300 prospectively studied blood donors. For the diagnosis of significant fibrosis by the METAVIR scoring system, the areas under the receiver operating characteristics curves (AUROC) ranged from 0.73 to 0.87. For the diagnosis of significant histological activity, the AUROCs ranged from 0.75 to 0.86. At a cut off of 0.31, the FT negative predictive value for excluding significant fibrosis (prevalence 0.31) was 91%. At a cut off of 0.36, the ActiTest negative predictive value for excluding significant necrosis (prevalence 0.41) was 85%. In three studies there was a direct comparison in the same patients of FT versus other biochemical markers, including hyaluronic acid, the Forns index, and the APRI index. All the comparisons favored FT (P < 0.05). There were no differences between the AUROCs of FT-AT according to genotype or viral load. The AUROCs of FT-AT for consecutive stages of fibrosis and grades of necrosis were the same for both moderate and extreme stages and grades. A conversion table was constructed between the continuous FT-AT values (0.00 to 1.00) and the expected semi-quantitative fibrosis stages (F0 to F4) and necrosis grades (A0 to A3). CONCLUSIONS: Based on these results, the use of the biochemical markers of liver fibrosis (FibroTest) and necrosis (ActiTest) can be recommended as an alternative to liver biopsy for the assessment of liver injury in patients with chronic hepatitis C. In clinical practice, liver biopsy should be recommended only as a second line test, i.e., in case of high risk of error of biochemical tests.

Journal Article↗
PubMed2006

Laparoscopic diagnostic peritoneal lavage (L-DPL): A method for evaluation of penetrating abdominal stab wounds.

BACKGROUND: The management of penetrating abdominal stab wounds has been the subject of continued reappraisal and controversy. In the present study a novel method which combines the use of diagnostic laparoscopy and DPL, termed laparoscopic diagnostic peritoneal lavage (L-DPL) is described METHOD: Five trauma patients with penetrating injuries to the lower chest or abdomen were included. Standard videoscopic equipment is utilized for the laparoscopic trauma evaluation of the injured patient. When no significant injury is detected, the videoscope is withdrawn and 1000 mL of normal saline is infused through the abdominal trochar into the peritoneal cavity, and the effluent fluid studied for RBCs, WBC, amylase debry, bile as it is uced in regular diagnostic peritoneal lavage RESULTS: Laparoscopic peritoneal lavage (L-DPL) was then performed and proved to be negative in all 5 patients. RBC lavage counts above 100,000/mcrl were not considered as a positive lavage result, because the bleeding source was directly observed and controlled laparoscopically. All patients recovered uneventfully and were released within 3 days. This procedure combines the visual advantages of laparoscopy together with the sensitivity and specificty of DPL for the diagnosis of significant penetrating intra-abdominal injury, when the diagnostic strategy of selective consevatism for abdominal stab wounds is adopted. CONCLUSION: A method of laparoscopic diagnostic peritoneal lavage (L-DPL) in hemodynamically stable patients with penetrating lower thoracic or abdominal stab wounds is described. The method is especially applicable for trauma surgeons with only basic experience in laparoscopic technique. This procedure is used to obtain conclusive evidence of significant intra-abdominal injury, confirm peritoneal penetration, control intra-abdominal bleeding, and repair lacerations to the diaphragm and abdominal wall. The combination of laparoscopy and DPL afforded by the L-DPL method adds to the sensitivity and specificity of DPL, and avoids under or over sesitivty, that have limited the use of DPL in the hemodynamically stable trauma patients with suspicious or proven peritoneal penetration.

Journal Article↗
PubMed2006

Women undergoing breast diagnostics: the lived experience of spirituality.

PURPOSE/OBJECTIVES: To explore perceptions of spirituality in women who had undergone a breast diagnostic experience. RESEARCH APPROACH: Qualitative, phenomenologic study using Giorgi's approach. SETTING: An outpatient comprehensive breast assessment center. PARTICIPANTS: 20 Caucasian women, aged 30-89, who had just completed the diagnostic process, including definitive diagnosis, regarding a breast abnormality. METHODOLOGIC APPROACH: In-depth, semistructured, tape-recorded, and transcribed interviews analyzed using the Giorgi method of coding, transforming, and synthesizing data. MAIN RESEARCH VARIABLES: Descriptions of spirituality, spiritual needs, and supporting spirituality. FINDINGS: Two themes emerged: creating a focused isolation and seeking connections. Women created a private mental world in which to concentrate on the stressful diagnostic process. Within the isolation, women explored their personal strength and their connection to God or their spiritual beliefs. When the stress began to overwhelm, they sought out loved ones for support and diversion. Women found the center's staff to be supportive; however, many did not wish to speak to an agency chaplain during the uncertain period. CONCLUSIONS: Women needed to handle the stress alone, with reliance on spirituality and God that was balanced with a need for specific connections to family members or close friends. INTERPRETATION: Nurses can support women's need to focus and can assist family members to understand their role during the diagnostic period. The diagnostic period can be used to talk with women about their spiritual beliefs, their needs, and possible referral to a chaplain.

Adult↗
PubMed2004

Diagnostic stability in a Dutch psychosis incidence cohort.

BACKGROUND: No study outside the UK has examined the diagnostic stability of psychotic disorders in a population-based sample. AIMS: To determine diagnostic stability in a Dutch population-based psychosis incidence cohort, to examine the frequencies of diagnostic shifts to and from schizophrenic disorders and to report the revised relative risks of schizophrenic disorders for immigrants. METHOD: A 30-month follow-up study assessed the cohort (n=181) by means of face-to-face diagnostic interviews. RESULTS: Diagnostic stability of schizophrenic disorders was high (91%), but lower for other psychotic disorders. At follow-up, the initial diagnosis was adjusted to schizophrenic disorder more often than that the reverse occurred. Almost half (49%) of the patients who were not initially diagnosed as having a schizophrenic disorder received this diagnosis at follow-up. The relative risks for most immigrant groups were stable. CONCLUSIONS: Schizophrenic disorders are underdiagnosed, rather than overdiagnosed, at first presentation.

Cohort Studies↗
PubMedDate not supplied

Identifying diagnostic studies in MEDLINE: reducing the number needed to read.

OBJECTIVES: The search filters in PubMed have become a cornerstone in information retrieval in evidence-based practice. However, the filter for diagnostic studies is not fully satisfactory, because sensitive searches have low precision. The objective of this study was to construct and validate better search strategies to identify diagnostic articles recorded on MEDLINE with special emphasis on precision. DESIGN: A comparative, retrospective analysis was conducted. Four medical journals were hand-searched for diagnostic studies published in 1989 and 1994. Four other journals were hand-searched for 1999. The three sets of studies identified were used as gold standards. A new search strategy was constructed and tested using the 1989-subset of studies and validated in both the 1994 and 1999 subsets. We identified candidate text words for search strategies using a word frequency analysis of the abstracts. According to the frequency of identified terms, searches were run for each term independently. The sensitivity, precision, and number needed to read (1/precision) of every candidate term were calculated. Terms with the highest sensitivity x precision product were used as free text terms in combination with the MeSH term "SENSITIVITY AND SPECIFICITY" using the Boolean operator OR. In the 1994 and 1999 subsets, we performed head-to-head comparisons of the currently available PubMed filter with the one we developed. MEASUREMENTS: The sensitivity, precision and the number needed to read (1/precision) were measured for different search filters. RESULTS: The most frequently occurring three truncated terms (diagnos*; predict* and accura*) in combination with the MeSH term "SENSITIVITY AND SPECIFICITY" produced a sensitivity of 98.1 percent (95% confidence interval: 89.9-99.9%) and a number needed to read of 8.3 (95% confidence interval: 6.7-11.3%). In direct comparisons of the new filter with the currently available one in PubMed using the 1994 and 1999 subsets, the new filter achieved better precision (12.0% versus 8.2% in 1994 and 5.0% versus 4.3% in 1999. The 95% confidence intervals for the differences range from 0.05% to 7.5% (p = 0.041) and -1.0% to 2.3% (p = 0.45), respectively). The new filter achieved slightly better sensitivities than the currently available one in both subsets, namely 98.1 and 96.1% (p = 0.32) versus 95.1 and 88.8% (p = 0.125). CONCLUSIONS: The quoted performance of the currently available filter for diagnostic studies in PubMed may be overstated. It appears that even single external validation may lead to over optimistic views of a filter's performance. Precision appears to be more unstable than sensitivity. In terms of sensitivity, our filter for diagnostic studies performed slightly better than the currently available one and it performed better with regards to precision in the 1994 subset. Additional research is required to determine whether these improvements are beneficial to searches in practice.

Diagnosis↗
PubMed2003

Integrating nursing diagnostic concepts into the medical entities dictionary using the ISO Reference Terminology Model for Nursing Diagnosis.

OBJECTIVE: The purposes of the study were (1) to evaluate the usefulness of the International Standards Organization (ISO) Reference Terminology Model for Nursing Diagnoses as a terminology model for defining nursing diagnostic concepts in the Medical Entities Dictionary (MED) and (2) to create the additional hierarchical structures required for integration of nursing diagnostic concepts into the MED. DESIGN AND MEASUREMENTS: The authors dissected nursing diagnostic terms from two source terminologies (Home Health Care Classification and the Omaha System) into the semantic categories of the ISO model. Consistent with the ISO model, they selected Focus and Judgment as required semantic categories for creating intensional definitions of nursing diagnostic concepts in the MED. Because the MED does not include Focus and Judgment hierarchies, the authors developed them to define the nursing diagnostic concepts. RESULTS: The ISO model was sufficient for dissecting the source terminologies into atomic terms. The authors identified 162 unique focus concepts from the 266 nursing diagnosis terms for inclusion in the Focus hierarchy. For the Judgment hierarchy, the authors precoordinated Judgment and Potentiality instead of using Potentiality as a qualifier of Judgment as in the ISO model. Impairment and Alteration were the most frequently occurring judgments. CONCLUSIONS: Nursing care represents a large proportion of health care activities; thus, it is vital that terms used by nurses are integrated into concept-oriented terminologies that provide broad coverage for the domain of health care. This study supports the utility of the ISO Reference Terminology Model for Nursing Diagnoses as a facilitator for the integration process.

Dictionaries, Medical as Topic↗
PubMed2005

A longitudinal look at parent-child diagnostic agreement in youth treated for anxiety disorders.

This study examined diagnostic agreement between children and their parents for seventy 9- to 13-year-olds (45 boys and 25 girls) who had received cognitive-behavioral treatment for anxiety disorders. Parent-child diagnostic rates and agreements for generalized anxiety disorder, separation anxiety disorder, and social phobia were evaluated at 3 time points: pretreatment, posttreatment, and 7.4-year follow-up. Results indicate that parent-child diagnostic agreement was typically poor to moderate (kappa = -.03 to .64) and that estimates of agreement remained relatively unchanged (a) following treatment and (b) as the children enter adolescence and young adulthood. Parent-daughter agreement was better than parent-son agreement in some cases. Although it remains unclear whether parent or child diagnostic information is most accurate, positive treatment outcome appears to be possible despite poor parent-child diagnostic agreement.

Adolescent↗
PubMed2005

Thyrotropin receptor/thyroglobulin messenger ribonucleic acid in peripheral blood and fine-needle aspiration cytology: diagnostic synergy for detecting thyroid cancer.

RT-PCR for thyroglobulin (Tg) and TSH receptor (TSHR) mRNA has been used to detect circulating thyroid cancer cells. Little is known, however, regarding the preoperative sensitivity of this test to detect cancer. Seventy-two patients with thyroid disease (36 with malignancy and 36 with benign disease) were evaluated preoperatively. TSHR and Tg mRNA transcripts were detected by RT-PCR assays, previously determined to be specific for cancer cells. There was 100% concordance between TSHR and Tg mRNA RT-PCR results. Of 36 cancer patients, 11 had recurrent disease, and all were positive by RT-PCR. Among 25 patients with no prior thyroid surgery, 18 tested positive preoperatively (sensitivity 72%). Seven of 36 patients with benign disease tested positive (specificity 80%). The overall preoperative diagnostic accuracy was 77%. Preoperative fine-needle aspiration (FNA) biopsy was performed on 46 of 61 patients with no prior thyroid surgery. FNA was diagnostic in 28 (61%) patients. Preoperative cytology was adequate but not diagnostic in 18 (39%) patients. RT-PCR correctly classified 14 of these 18 patients with indeterminate FNA, and the test detected three of four cancer patients as positive (75% sensitive) and 11 of 14 patients (78% specific) with benign disease as negative. The combined diagnostic performance characteristics for RT-PCR and FNA cytology were sensitivity = 95%, specificity = 83%, and diagnostic accuracy = 89%, with positive and negative predictive values of 84 and 95%, respectively. Our results suggest that the molecular detection of circulating thyroid cancer cells by RT-PCR for TSHR/Tg mRNA complements FNA cytology in the preoperative differentiation of benign from malignant thyroid disease and their combined use may save unnecessary surgeries.

Adolescent↗
PubMed2005

Detection of serum deoxyribonucleic acid methylation markers: a novel diagnostic tool for thyroid cancer.

CONTEXT: Serum DNA methylation markers may potentially be useful in diagnosing thyroid cancer and monitoring its recurrence. OBJECTIVE: The objective of the study was to assess the utility of serum DNA methylation as a diagnostic test for patients with thyroid nodules and a monitoring test to detect thyroid cancer recurrence in previously treated patients. DESIGN, SETTING, AND SUBJECTS: Using real-time quantitative methylation-specific PCR, we analyzed the methylation status of five genes (CALCA, CDH1, TIMP3, DAPK, and RARbeta2) on 96 bisulfite-treated serum DNA samples isolated preoperatively from either solid thyroid nodule patients or patients in follow-up for history of treated thyroid cancer. MAIN OUTCOME MEASURE: Diagnostic sensitivity, specificity, and accuracy of serum DNA methylation marker for thyroid cancer were measured. RESULTS: For the patients with thyroid nodules, when a positive result was defined by a serum methylation level above the appropriately chosen cutoff value for any one of the five genes, the preoperative diagnostic sensitivity for thyroid cancer was 68% (26 of 38), the specificity was 95% (18 of 19), and the overall preoperative diagnostic accuracy was 77%, with positive and negative predictive values of 96 and 60%, respectively. In a subset of patients with cytologically indeterminate thyroid nodules, serum DNA methylation testing could correctly diagnose eight of 11 (73%) cancers and four of four (100%) benign tumors, with a diagnostic accuracy of 80%. We also analyzed these serum DNA methylation markers in 39 previously treated thyroid cancer patients. Among the 10 patients proved to have recurrent disease by conventional measures, seven (70%) were positive on methylation testing. Among the 29 patients who had no corroboration of residual or recurrent disease by conventional studies, six (21%) were positive for serum DNA methylation markers. CONCLUSIONS: We have demonstrated the potential usefulness of serum DNA methylation markers as a novel tool for differential diagnosis of solid thyroid nodules and thyroid cancer recurrence monitoring.

Biomarkers↗
PubMed1997

Free insulin-like growth factor I serum levels in 1430 healthy children and adults, and its diagnostic value in patients suspected of growth hormone deficiency.

Serum levels of total insulin-like growth factor I (IGF-I) and IGF-binding protein-3 (IGFBP-3) reflect endogenous GH secretion in healthy children, which makes them good diagnostic markers for screening of GH deficiency (GHD) in short children, although some controversy still exists. Only a minor fraction of the total IGF-I circulates in its free form, which is believed to be the biologically active form. However, our knowledge of the clinical or physiological value of determination of free IGF-I in serum is limited at present. In adults, the diagnostic value of total IGF-I and IGFBP-3 determinations in patients suspected of GHD has only been reported in a few studies, whereas no previous reports on the diagnostic value of free IGF-I levels in adults suspected of GHD exist. Serum levels of free IGF-I were determined in 1430 healthy children, adolescents, and adults by a newly developed, commercially available immunoradiometric assay (Diagnostic Systems Laboratories) to establish valid normative data for this analysis. We studied the diagnostic value of free IGF-I in relation to total IGF-I and IGFBP-3 determinations in adults who were suspected of GHD. A GH provocative test, using oral clonidine, was performed in 108 adult patients who had previously been treated with GH in childhood. In healthy subjects, free IGF-I levels increased during childhood, with the highest mean values during puberty. After puberty, a subsequent decline in serum levels of free IGF-I was apparent. We found, unmeasurable free IGF-I values in 34 of the prepubertal children (3.3%). All individuals over 8 yr of age had measurable free IGF-I levels that amounted to approximately 1% of the total IGF-I concentrations. Free IGF-I levels were below--2 SD in 56 of 79 GHD patients (sensitivity, 71%) and above--2 SD in 24 of 29 patients with a normal GH response (specificity, 83%). Multiple linear regression analysis demonstrated that free IGF-I was significantly dependent on peak GH levels, duration of the disease, and number of other pituitary axes affected. We conclude that free IGF-I serum levels increase during childhood with a peak in puberty, whereafter free IGF-I levels return to prepubertal levels. Three percent of healthy prepubertal children had unmeasurable free IGF-I levels using this assay. We found that determination of the free IGF-I serum concentration may predict the outcome of a GH provocative test in adults suspected of GHD, but that a single determination of free IGF-I offered no significant advantage compared to determination of total IGF-I or IGFBP-3 serum levels.

Adolescent↗
PubMed2002

Diagnostic 131-iodine whole-body scan may be avoided in thyroid cancer patients who have undetectable stimulated serum Tg levels after initial treatment.

The follow-up of differentiated thyroid cancer after total thyroidectomy and thyroid ablation is commonly based on serum Tg determination and 131-iodine ((131)I) diagnostic whole-body scan (WBS) performed in the hypothyroid state, 6-12 months after thyroid ablation. Based on the greater sensitivity of Tg measurement, with respect to WBS, the diagnostic yield of diagnostic WBS has been questioned in patients who are off L-T(4) therapy and have undetectable Tg levels. The aim of the present retrospective study was to evaluate the diagnostic relevance of (131)I WBS performed after thyroid remnant ablation, in patients with undetectable serum Tg and off thyroid hormone therapy. The study included 315 of 662 consecutive patients (47.6%) treated in our department between 1980 and 1990, who, at the first control WBS after thyroid ablation, had undetectable serum Tg levels in the hypothyroid state. There were 54 men (17%) and 261 women (83%), with a mean age of 40.9 +/- 13.1 yr (range, 12-76), followed for a mean of 12 +/- 2.8 (range, 9-19) yr. The control WBS was negative in 225 (71.4%) patients and positive for persistent areas of thyroid bed uptake, frequently of very low significance, in 90 (28.6%). No local or distant metastases were discovered. At the last follow-up visit (1999-2000), 281 (89.2%) patients showed complete remission, with undetectable serum Tg off L-T(4) and negative WBS. Persistent thyroid bed uptake, with undetectable levels of Tg, was observed in 29 patients (9.2%) studied during L-T(4) withdrawal. Only 2 patients (0.6%) experienced local recurrence (lymph-node metastases) during their follow-up. In conclusion, our data suggest that the presence of undetectable levels of serum Tg off L-T(4) at the time of the first control WBS after initial treatment, is highly predictive of complete and persistent remission. With the exception of detecting persistent thyroid bed uptake in a minority of cases, the control WBS has never given information that could influence the following therapeutic strategy. On this basis, we propose that the diagnostic (131)I WBS may be avoided in patients with undetectable levels of Tg off L-T(4). These patients may be monitored with clinical examination, neck ultrasound, and serum Tg measurements on L-T(4).

Adolescent↗
PubMed2005

Diagnostic evaluation of patients with a brain mass as the presenting manifestation of cancer.

BACKGROUND: Patients with a newly detected brain mass and no history of cancer often undergo extensive diagnostic testing in search of a systemic primary neoplasm prior to selection of a biopsy site, potentially leading to unnecessary expense and delay. We sought patterns in the evaluation of these patients to allow rapid selection of a biopsy site. METHODS: We compared the diagnostic evaluation of 176 patients with newly detected brain masses who were ultimately determined to have a metastatic or primary lesion. RESULTS: In 88 patients presenting with brain metastasis, lung cancer was markedly overrepresented as a primary tumor, occurring in 82% of patients. Brain MRI and chest CT together identified the site for diagnostic biopsy in all except for two of the 176 patients. One-half of the patients with metastasis had brain biopsy as the primary diagnostic procedure, with 80% undergoing a craniotomy rather than needle biopsy. The initial management decision in the majority of metastasis patients was whether to perform a craniotomy for resection of tumor. Whereas patients with single and cerebellar lesions were most likely to undergo craniotomy, the extent of systemic disease did not affect the decision to recommend a neurosurgical procedure. The average time to biopsy for patients with metastatic and primary tumors was 4.7 days and 6.0 days. In this retrospective population, we estimated that evaluation with brain MRI and chest CT, followed by an early neurosurgical decision, could reduce the time to diagnosis by at least 10%. CONCLUSIONS: Chest CT and brain MRI, if used together as initial diagnostic studies, would have identified a biopsy site in 97% of patients with a newly detected brain mass.

Biopsy↗
PubMed2006

Revised diagnostic criteria for neuromyelitis optica.

BACKGROUND: The authors previously proposed diagnostic criteria for neuromyelitis optica (NMO) that facilitate its distinction from prototypic multiple sclerosis (MS). However, some patients with otherwise typical NMO have additional symptoms not attributable to optic nerve or spinal cord inflammation or have MS-like brain MRI lesions. Furthermore, some patients are misclassified as NMO by the authors' earlier proposed criteria despite having a subsequent course indistinguishable from prototypic MS. A serum autoantibody marker, NMO-IgG, is highly specific for NMO. The authors propose revised NMO diagnostic criteria that incorporate NMO-IgG status. METHODS: Using final clinical diagnosis (NMO or MS) as the reference standard, the authors calculated sensitivity and specificity for each criterion and various combinations using a sample of 96 patients with NMO and 33 with MS. The authors used likelihood ratios and logistic regression analysis to develop the most practical and informative diagnostic model. RESULTS: Fourteen patients with NMO (14.6%) had extra-optic-spinal CNS symptoms. NMO-IgG seropositivity was 76% sensitive and 94% specific for NMO. The best diagnostic combination was 99% sensitive and 90% specific for NMO and consisted of at least two of three elements: longitudinally extensive cord lesion, onset brain MRI nondiagnostic for MS, or NMO-IgG seropositivity. CONCLUSIONS: The authors propose revised diagnostic criteria for definite neuromyelitis optica (NMO) that require optic neuritis, myelitis, and at least two of three supportive criteria: MRI evidence of a contiguous spinal cord lesion 3 or more segments in length, onset brain MRI nondiagnostic for multiple sclerosis, or NMO-IgG seropositivity. CNS involvement beyond the optic nerves and spinal cord is compatible with NMO.

Adolescent↗
PubMed1994

The diagnostic value of SPECT with Tc 99m HMPAO in Alzheimer's disease: a population-based study.

We studied the diagnostic accuracy of single-photon emission computed tomography (SPECT) with technetium 99m-labeled hexamethylpropylene amine oxime (Tc 99m HMPAO) in 48 patients with probable Alzheimer's disease (AD) according to NINCDS-ADRDA criteria and in 60 controls recruited from a population-based study. With logistic regression, we identified decreased temporal regional cerebral blood flow as the best discriminating variable between patients and controls. Receiver-operator characteristic curves showed that the discriminative ability of SPECT improved with increasing dementia severity. With specificity set at 90%, sensitivity figures were 42% in mild, 56% in moderate, and 79% in severe AD. The diagnostic gain as a function of the prior probability of the disease being present was computed for those with mild AD. When the prior probability varied at around 50%, the diagnostic gain for mild AD patients was substantial (a maximum of 34%) for a positive test result but poor for a negative test result. The results suggest that the practical usefulness of SPECT as a diagnostic adjunct in patients suspected of having mild AD is confined to situations in which, on clinical grounds, there is considerable diagnostic doubt.

Aged↗