110 resultados para fault diagnosis,


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Diagnosis of autoimmune hepatitis (AIH) may be challenging. However, early diagnosis is important because immunosuppression is life-saving. Diagnostic criteria of the International Autoimmune Hepatitis Group (IAIHG) were complex and purely meant for scientific purposes. This study of the IAIHG aims to define simplified diagnostic criteria for routine clinical practice. Candidate criteria included sex, age, autoantibodies, immunoglobutins, absence of viral hepatitis, and histology. The training set included 250 AIH patients and 193 controls from 11 centers worldwide. Scores were built from variables showing predictive ability in univariate analysis. Diagnostic value of each score was assessed by the area under the receiver operating characteristic (ROC) curve. The best score was validated using data of an additional 109 AIH patients and 284 controls. This score included autoantibodies, immunoglobulin G, histology, and exclusion of viral hepatitis. The area under the curve for prediction of AIH was 0.946 in the training set and 0.91 in the validation set. Based on the ROC curves, two cutoff points were chosen. The score was found to have 88% sensitivity and 97% specificity (cutoff >= 6) and 81% sensitivity and 99% specificity (cutoff 2:7) in the validation set. Conclusion: A reliable diagnosis of AIH can be made using a very simple diagnostic score. We propose the diagnosis of probable AIH at a cutoff point greater than 6 points and definite AIH 7 points or higher.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objective: The aim of the study was to evaluate clinical and laboratorial features of 1234 patients with different etiologies of hyper-prolactinemia, as well as the response of 388 patients with prolactinomas to dopamine agonists. Design, setting, and patients: A total of 1234 hyperprolactinemic patients from 10 Brazilian endocrine centers were enrolled in this retrospective study. Main outcome measure: PRL measurement, thyroid function tests, and screening for macroprolactin were conducted. Results: Patients were subdivided as follows: 56.2% had prolactinomas, 14.5% drug-induced hyperprolactinemia, 9.3% macroprolactinemia, 6.6% non-functioning pituitary adenomas, 6.3% primary hypothyroidism, 3.6% idiopathic hyperprolactinemia, and 3.2% acromegaly. Clinical manifestations were similar irrespective of the etiology of the hyperprolactinemia. The highest PRL levels were observed in patients with prolactinomas but there was a great overlap in PRL values between all groups. However, PRL>500 ng/ml allowed a clear distinction between prolactinomas and the other etiologies. Cabergoline (CAB) was more effective than bromocriptine (BCR) in normalizing PRL levels (81.9% vs 67.1%, p<0.0001) and in inducing significant tumor shrinkage and complete disappearance of tumor mass. Drug resistance was observed in 10% of patients treated with CAB and in 18.4% of those that used BCR (p=0.0006). Side-effects and intolerance were also more common in BCR-treated patients. Conclusion: Prolactinomas, drug-induced hyperprolactinemia, and macroprolactinemia were the 3 most common causes of hyperprolactinemia. Although PRL levels could not reliably define the etiology of hyperprolactinemia, PRL values >500 ng/ml were exclusively seen in patients with prolactinomas. CAB was significantly more effective than BCR in terms of prolactin normalization, tumor shrinkage, and tolerability.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Sporadic lymphangiectasias are commonly found throughout the small bowel and are considered to be normal. Not uncommonly, lymphangiectasias are pathologic and can lead to mid-gastrointestinal bleeding, abdominal pain and protein-losing enteropathy. Pathologic lymphangiectasias of the small bowel include primary lymphangiectasia, secondary lymphangiectasia and lymphaticovenous malformations. In this report we present three different cases of small bowel lymphangiectasia detected by double balloon enteroscopy. The patients were diagnosed with South American blastomycosis, tuberculosis and primary small bowel lymphangioma. Copyright (C) 2009 S. Karger AG, Basel

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objectives/Hypothesis: Polysomnography (PSG) is the gold-standard method for diagnosing obstructive sleep apnea (OSA). However, the gap between demand and capacity in performing PSG is a major health-care problem. We sought to validate a short day-time induced sleep for the diagnosis of OSA. Study Design: Prospective diagnostic method validation. Methods: We studied 25 consecutive patients referred to the sleep laboratory and 15 healthy volunteers. All subjects were evaluated by means of full overnight PSG (Full-PSG) and short day-time induced-sleep PSG (Induced-PSG). Sleep was monitored during both procedures (Embla, 16 channels). Sleep was induced by slow intravenous drip infusion of midazolam. Results: The population studied (N = 40) was 60% male (mean age, 42 +/- 10 years; body mass index, 29 +/- 6.5 kg/m(2)). Sleep was successfully induced in all subjects, and no complications were observed (midazolam doses, 6.2 +/- 3.8 mg; time of induced sleep 41.5 +/- 18.9 minutes). The apnea-hypopnea index (AHI) and minimal oxygen saturation during Full-PSG versus Induced-PSG were similar: median AHI (with 25%-75% interquartile range) was 13 (3-35) events per hour versus 17 (4-36) events per hour, and median oxygen saturation was 84% (75-90) versus 85% (76-92); P = .89 and P = .53, respectively. The majority of the respiratory events during induced sleep were obstructive and similar to those observed during Full-PSG. AHI and lowest oxygen saturation during Induced-PSG correlated significantly with Full-PSG (r = 0.67 and r = 0.77, respectively). Sensitivity and specificity for the diagnosis of OSA (AHI > 15 events per hour) by Induced-PSG were 0.83 and 0.72, respectively. Conclusions: Induced-PSG by midazolam during the day is safe and correlates with Full-PSG; it therefore is a promising alternative method in the diagnosis of OSA.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objective To describe the natural history of fetuses presenting with pleural effusion. Methods Between January 2005 and December 2009 all fetuses diagnosed with pleural effusion were followed up. Fetuses were divided into three groups: I, isolated pleural effusion; II, associated structural anomalies but normal karyotype; and III, chromosomal anomalies. Univariate and multivariate analyses were performed to determine the association between prenatal ultrasound findings and perinatal death. Results Fifty-six fetuses were included in the study. Associated structural or chromosomal anomalies occurred in 75.0% (42/56) of cases. Bilateral pleural effusion and fetal hydrops were associated with each other (p < 0.01) and with perinatal death (p < 0.05). Multivariate analysis indicated that only the presence of associated abnormalities was a statistical determinant of perinatal death (OR, 3.56; 95% CI, 1.48-5.64; p < 0.01). Conclusion Fetal pleural effusion is often associated with other abnormalities, and this association has poor perinatal outcome. Copyright (C) 2011 John Wiley & Sons, Ltd.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This study evaluated the Mycobacterium tuberculosis protein antigen MPT-51, the trimeric antigen 85 (Ag85) complex, and Bacillus Calmette-Guerin (BCG) in an indirect ELISA to diagnose bovine tuberculosis (TB) from serum samples. Serum was collected from 208 intra-dermal tuberculin test (ITT)-positive and 54 ITT-negative animals from a region where bovine TB is endemic. Using the Ag85 and BCG antigens, the indirect ELISA was able to discriminate ITT-positive from ITT-negative animals. This level of discrimination was not achieved when using the MPT-51 antigen. The highest sensitivity (Se) and specificity (Sp) of the test was found when BCG was used (Se, 82%; Sp, 91%). Further work in different epidemiological settings and with larger numbers of animals will be required to validate these findings. (C) 2009 Elsevier Ltd. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this work, we take advantage of association rule mining to support two types of medical systems: the Content-based Image Retrieval (CBIR) systems and the Computer-Aided Diagnosis (CAD) systems. For content-based retrieval, association rules are employed to reduce the dimensionality of the feature vectors that represent the images and to improve the precision of the similarity queries. We refer to the association rule-based method to improve CBIR systems proposed here as Feature selection through Association Rules (FAR). To improve CAD systems, we propose the Image Diagnosis Enhancement through Association rules (IDEA) method. Association rules are employed to suggest a second opinion to the radiologist or a preliminary diagnosis of a new image. A second opinion automatically obtained can either accelerate the process of diagnosing or to strengthen a hypothesis, increasing the probability of a prescribed treatment be successful. Two new algorithms are proposed to support the IDEA method: to pre-process low-level features and to propose a preliminary diagnosis based on association rules. We performed several experiments to validate the proposed methods. The results indicate that association rules can be successfully applied to improve CBIR and CAD systems, empowering the arsenal of techniques to support medical image analysis in medical systems. (C) 2009 Elsevier B.V. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Chagas` disease caused by Trypanosoma cruzi is endemic in Latin America. T. cruzi presents heterogeneous populations and comprises two main genetic lineages, named T. cruzi I and T. cruzi II. Diagnosis in the chronic phase is based on conventional serological tests, including indirect immunofluorescence (IIF) and enzyme-linked immunosorbent assay (ELISA), and diagnosis in the acute phase based on parasitological methods, including hemoculture. The objective of this study was to evaluate the diagnostic procedures of Chagas` disease in adult patients in the chronic phase by using a PCR assay and conventional serological tests, including TESA-blot as the gold standard. Samples were obtained from 240 clinical chronic chagasic patients. The sensitivities, compared to that of TESA-blot, were 70% for PCR using the kinetoplast region, 75% for PCR using the nuclear repetitive region, 99% for IIF, and 95% for ELISA. According to the serological tests results, we recommend that researchers assess the reliability and sensitivity of the commercial kit Chagatest ELISA recombinant, version 3.0 (Chagatest Rec v3.0; Wiener Lab, Rosario, Argentina), due to the lack of sensitivity. Based on our analysis, we concluded that PCR cannot be validated as a conventional diagnostic technique for Chagas` disease. These data have been corroborated by low levels of concordance with serology test results. It is recommended that PCR be used only for alternative diagnostic support. Using the nuclear repetitive region of T. cruzi, PCR could also be applicable for monitoring patients receiving etiologic treatment.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this paper, we propose a method based on association rule-mining to enhance the diagnosis of medical images (mammograms). It combines low-level features automatically extracted from images and high-level knowledge from specialists to search for patterns. Our method analyzes medical images and automatically generates suggestions of diagnoses employing mining of association rules. The suggestions of diagnosis are used to accelerate the image analysis performed by specialists as well as to provide them an alternative to work on. The proposed method uses two new algorithms, PreSAGe and HiCARe. The PreSAGe algorithm combines, in a single step, feature selection and discretization, and reduces the mining complexity. Experiments performed on PreSAGe show that this algorithm is highly suitable to perform feature selection and discretization in medical images. HiCARe is a new associative classifier. The HiCARe algorithm has an important property that makes it unique: it assigns multiple keywords per image to suggest a diagnosis with high values of accuracy. Our method was applied to real datasets, and the results show high sensitivity (up to 95%) and accuracy (up to 92%), allowing us to claim that the use of association rules is a powerful means to assist in the diagnosing task.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The fact that the diagnosis of infection with dengue virus is usually made by detecting IgM antibodies during the convalescent phase of the disease interferes with disease management and, consequently, with reducing mortality rates. This study evaluated the sensitivity and specificity of detection of NS1 in samples of patients suspected of acute dengue virus infection in Brazil. The results were used to institute treatment and the sensitivity and specificity of detection of NS1 were compared to the results of detection of IgM, virus isolation, and RT-PCR. Detection of NS1 yielded better results than RTPCR and virus isolation. When considering IgM detection and RT-PCR positive results as ""gold standards,"" the sensitivity and specificity of the NS1 assay were 95.9% and 81.1%, respectively. All patients enrolled in the study were treated promptly and had an uneventful course of the disease. The detection of NS1 provided better results than the diagnostic techniques used currently during the acute phase of disease (RT-PCR and virus isolation). Detection of NS1 is an important tool for the diagnosis of acute dengue infection, particularly in highly endemic areas, allowing for rapid treatment of patients and reduction of disease burden. J. Med. Virol. 82: 1400-1405, 2010. (C) 2010 Wiley-Liss, Inc.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Mucopolysaccharidoses (MPS) form a group of inherited metabolic disorders characterized by intralysosomal storage of glycosaminoglycans. This study aimed to investigate the path followed by Brazilian patients from birth to diagnosis. An interview was conducted with patient`s parents or guardians with subsequent review of patient`s medical records. One hundred thirteen patients with MPS were included (MPS I: 18, MPS II: 43, MPS III: 2, MPS IIIB: 3, MPS IIIC: 1, MPS IVA: 15, MPS IVB: 1, MPS VI: 29, MPS VII: 1) from 97 families. Median age at the onset of sings/symptoms was 18 months (MPS I: 18, MPS II: 24, MPS IVA: 8, MPS IV: 8). Skeletal abnormalities (for MPS IVA and MPS VI), joint contracures (for MPS II), and typically first signs/symptoms. Several health professionals were involved in patient`s care as of the onset of symptoms until biochemical diagnosis was established. Median age at diagnosis was 76 months (MPS I: 75, MPS II: 95, MPS IVA: 75, MPS VI: 52). Considering the group as a whole, there was a 4.8-year delay between the onset of signs/symptoms and establishment of the diagnosis. Considering that specific therapies are available for some of these disorders and that early treatment is likely to change more favorably the natural history of the disease, efforts should be made to minimize this delay. We believe that this situation can be improved by measures that both increase awareness of health professionals about MPS and improve access to diagnostic tests. (C) 2008 Wiley-Liss, Inc.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

SETTING: Itaborai Municipality in Rio de Janeiro, Brazil. OBJECTIVE: To evaluate access to tuberculosis (TB) diagnosis for users of the Family Health Program (FHP) and Reference Ambulatory Units (RAUs). DESIGN : A cross-sectional study was conducted in Itaborai City, Rio de Janeiro, Brazil. Between July and October 2007, a sample of 100 TB patients registered consecutively with the TB Control Program was interviewed using the primary care assessment tool. The two highest scores, describing `almost always` and `always`, or `good` and `very good`, were used as a cut-off point to define high quality access to diagnosis. RESULTS: FHP patients were older and had less education than RAU interviewees. Sex and overcrowding did not differ in the two groups. Patient groups did not differ with regard to the number of times care was sought at a unit, transport problems, cost of attending units and availability of consultation within 24 h. Adequate access to diagnosis was identified by 62% of the FHP patients and 53% of the RAU patients (P = 0.01). CONCLUSION: In Itaborai, Rio de Janeiro, TB patients believe that the FHP units provide greater access to TB diagnosis than RAUs. These findings will be used by the Department of Health to improve access to diagnosis in Itaborai.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: Inflammatory diseases stand out among sensory neuronopathies because, in their active phase, they can be treated with immunosuppressive agents. Immunosuppressive therapy may present severe adverse effects and requires previous inflammatory activity confirmation. Sensory neuronopathies are diagnosed based on clinical and EMG findings. Diagnostic confirmation and identification of inflammatory activity are based on sensory ganglion histopathological examination. We describe the surgical technique used for dorsal root ganglionectomy in patients with clinical/EMG diagnosis of sensory neuronopathies. Methods: The sensory ganglion was obtained from 15 patients through a small T7-T8 hemilaminectomy and foraminotomy to expose the C7 root from its origin to the spinal nerve bifurcation. In 6 patients, the dural cuff supposed to contain the ganglion was resected en bloc; and in 9 patients, the ganglion was obtained through a longitudinal incision of the dural cuff and microsurgical dissection from the ventral and dorsal roots and radicular arteries. All ganglia were histopathologically examined. Results: No ganglion was found in the dural cuff in 2 patients submitted to en bloc removal, and the ganglion was removed in all patients who underwent microsurgical dissection. All but 2 patients that had ganglion examination presented a neuronopathy of nerve cell loss, 3 with mononuclear inflammatory infiltrate. These patients underwent immunosuppressive therapy, and 2 of them presented clinical improvement. No surgical complications were observed. Conclusions: Microsurgical dorsal root ganglionectomy for diagnosing inflammatory sensory ganglionopathies was effective and safe. Although safe, en bloc resection of the proximal dural cuff was not effective for this purpose. (c) 2008 Published by Elsevier Inc.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objective: To investigate the accuracy of the Brazilian version of the Addenbrooke Cognitive Examination-revised (ACE-R) in the diagnosis of mild Alzheimer disease (AD). Background: The ACE-R is an accurate and brief cognitive battery for the detection of mild dementia, especially for the discrimination between AD and frontotemporal dementia. Methods: The battery was administered to 31 patients with mild AD and 62 age-matched and education-matched cognitively healthy controls. Both groups were selected using the Dementia Rating Scale and were submitted to the ACE-R. Depression was ruled out in both groups by the Cornell Scale for Depression in Dementia. The performance of patients and controls in the ACE-R was compared and receiver operator characteristic curve analysis was undertaken to ascertain the accuracy of the instrument for the diagnosis of mild AD. Results: The mean scores at the ACE-R were 63.10 +/- 10.22 points for patients with AD and 83.63 +/- 7.90 points for controls. The cut-off score < 78 yielded high diagnostic accuracy (receiver operator characteristic area under the curve = 0.947), with 100% sensitivity, 82.26% specificity, 73.8% positive predictive value, and 100% negative predictive value. Conclusions: The Brazilian version of the ACE-R displayed high diagnostic accuracy for the identification of mild AD in the studied sample.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The differential diagnosis of renal tumors, particularly in adolescents, may be challenging. We describe an 11-year-old female with a primary intra-renal mass. Initial differential diagnoses included primitive neuroectodermal tumor (PNET), desmoplastic small round cell tumor (DSRCT), and Wilms Turner (WT). Extensive pathologic and molecular analysis on initial and relapsed tumor samples confirmed WT. The EWS-WTI and EWS-FL11 rearrange-merits, distinctive of DSRCT and PNET were negative. The differential diagnosis on monophasic blastemal WT may be complex. Primary renal DSRCT and MET have been rarely described. Nevertheless, molecular confirmation for these rare conditions may be necessary in selected cases. Pediatr Blood Cancer 2010;54:3 19-321. (C) 2009 Wiley-Liss, Inc.