[Value of contrast-enhanced MR enterography in pediatric Crohn's disease: preliminary study]. / Valeur de l'entéro-IRM avec injection de gadolinium dans la maladie de Crohn en pédiatrie: étude préliminaire.

OBJECTIVE: Feasibility study of contrast enhanced MR enterography without enteroclysis as a new diagnostic tool for children with known or suspected Crohn's disease. METHODS: We prospectively included 15 children, 8-18 years old, with clinical suspicion of Crohn's disease. MR enterography without enteroclysis was performed on a 1,5 T clinical MR system. A total of 1000 ml of mannitol 5% was orally administered 60 minutes prior to MRI. Coronal and axial breath-hold sequences were acquired. The following sequences were obtained: True-FISP, FLASH T1 2D/3D with Fat saturation before and after gadolinium injection. Two radiologists, blinded to patient information, independently reviewed all examinations to record image quality, the degree of distension of the distal ileum, the presence of abnormal bowel segments and the presence of extra-intestinal complications. MRI findings were correlated to sonographic, endoscopic and biological results (sensitivity, specificity, Kappa test). RESULTS: The examinations were considered of satisfactory diagnostic quality in 93.3% of patients. Respiratory artifacts were present in one case. The entire GI tract could be identified on all sequences. Distention of the distal ileum was recorded as good to excellent in 89% of healthy subjects. Five MR examinations were considered abnormal with isolated ileal involvement in 2 cases, ileocolic involvement in 2 cases, and isolated colonic involvement in 1 case. The sensitivity and specificity of MR for the positive diagnosis of Crohn's disease were 100% and 83% respectively. Three extra-intestinal complications were detected: one case of ileo-ileal fistula, not identified on ultrasonography, an asymptomatic anal fistula and a symptomatic inflammatory stricture. CONCLUSION: MR enterography without enteroclysis is a well tolerated, effective non invasive method in the evaluation of known or suspected Crohn's disease. Because of the absence of ionizing radiation, MR enterography should become the gold standard in pediatric patients.

[Detection of liver metastases in colorectal cancer on chemotherapy. Comparative study between MRI with teslascan and computed tomography with intravenous contrast media]. / Détection de métastases hépatiques du cancer colorectal sous chimiothérapie. Etude comparative en IRM avec Teslascan et tomodensitométrie avec injection iodée.

OBJECTIVE: To compare MRI of the liver with mangafodipir trisodium (MnDPDP) and computed tomography with intravenous contrast media in the follow-up of liver metastases in patient on chemotherapy for colorectal carcinoma. MATERIALS AND METHODS: This was a prospective study with patients on chemotherapy for liver metastases from colorectal cancer. Patients underwent both contrast-enhanced helical CT using 2 cc/kg contrast at 3 cc/sec and mangafodipir trisodium-enhanced MR imaging at 1.5 T using 2-3 cc/min contrast at 5 micro mol/kg within a two week interval. Two experienced radiologists independently reviewed all scans in a blinded fashion and recorded image quality as well as presence and number of liver lesions. Statistical analysis was performed using the wilcoxon signed rank test. RESULTS: All examinations were of good quality. A total of 71 lesions were detected at CT, with 69 lesions consistent with metastases and 2 lesions consistent with cysts. A total of 98 lesions were detected at MRI, with 97 consistent with metastases and 1 lesion consistent with a cyst. T1 weighted images with MnDPDP significantly detected two additional lesions compared to CT (p<0.05). No significant difference was demonstrated between T1 weighted images without MnDPDP and CT or between T2 weighted images and CT. CONCLUSION: Magnetic resonance imaging with MnDPDP is significantly more sensitive than unenhanced MRI and helical CT for the follow-up of liver lesions.

The risk of hospital-acquired GB virus C infection: a pilot case-control study.

The risk of hospital-acquired infection with GB virus C (GBV-C) was explored among 42 patients. The factors independently associated with detection of GBV-C RNA in serum were bronchoscopic examination [adjusted odds ratio (OR)=18.1 (95% confidence interval 1.3-255.3), P=0.03] and a history of illicit drug use [OR=14.5 (1.0-218.7), P=0.05]. In this cohort of patients, invasive procedures appear to be associated with GBV-C infection but not with hepatitis C virus (HCV) infection.

TT virus. A review of the literature.

In 1997, a new DNA virus was cloned by a Japanese team and designated TT virus (TTV). This virus seemed to be associated with non-A, non-G post-transfusion hepatitis. It was isolated by polymerase chain reaction (PCR) and was presumed to be human Circoviridae. The virus is heterogenous; 16 different genotypes are currently registered, and it can be classified as a "swarm" of at least 5 different viruses. Depending on the PCR technique used, the prevalence of infection ranges from 1.9 to 36% among blood donors, from 11.5 to 71% in hemodialysis patients, from 47 to 82% among patients with non-A, non-B or non-C fulminant hepatic failure, and the most elevated percentage is found in hemophiliacs. Epidemiological studies have established that the routes of TTV infection might be parenteral, oral-fecal, and possibly salivary. Mother-to-infant transmission is controversial. TTV may play a role in the pathogenesis of non-A, non-B or non-C fulminant hepatic failure. Patients co-infected with hepatitis C virus (HCV) and TTV have a significantly higher histological grade score than patients with isolated HCV infection. Treatment with interferon seems to decrease TT viremia, according to results obtained outside the context of clinical trials. TTV seems to be a light pathogenic virus. Its widespread presence in the blood of infected subjects contrasts with the apparent absence of pathological symptoms. PCR standardization is needed to clearly establish its real prevalence worldwide.

Efficacy of pneumococcal polysaccharide vaccine in immunocompetent adults: a meta-analysis of randomized trials.

The use of pneumococcal polysaccharide vaccine (PPV) is low in some countries, maybe because of doubts regarding its efficacy. This meta-analysis aims at combining evidence from randomized trials of PPV assessing its efficacy in preventing Streptococcus pneumoniae related diseases in immunocompetent adults. In the fourteen trials totalling 48,837 patients retrieved, PPV prevents definite pneumococcal pneumonia by 71%, presumptive pneumococcal pneumonia by 40%, and mortality due to pneumonia by 32%, but not all-cause pneumonia or death. No preventive effect was seen in the subgroup of patients aged 55 years or more, possibly due to a lack of statistical power.

Trial summary software.

Medical practice is most strongly founded when based on the results of well conducted clinical trials. Clinical trial results normally enter the domain of medical knowledge and practice through their publication in scientific journals. This in itself poses problems of accessibility and selection. The results of this is a slow and selective diffusion of new medical facts which has a consequent cost in human lives and human suffering. In an attempt to shorten this information path initiatives such as the Cochrane collaboration produce and maintain systematic reviews by speciality of the current state of knowledge. The ability to store a representation of a clinical trial in a standard form seems to us to be a necessary condition for the efficient and reproducible preparation of systematic reviews. Furthermore the consequent increased accessibility of research results due to the existence of the summaries would itself be of great use. In this aim a relational database client server system was developed and we publish here the results of our preliminary findings, including the data model, which we feel is an important contribution to the future discussion and development of computer based representations of clinical trial protocols and results and their use in clinical decision making.