Search PubMed⌕ Search

Biomedical subjects

M Tondeur

Publications and source records attributed to M Tondeur.

At least 19 recordsLinked to original sources

Enteral nutritional therapy for inducing remission of Crohn's disease.

BACKGROUND: The role of enteral nutrition in Crohn's disease is controversial. Increasing research on the mechanisms by which nutritional therapy improves the clinical well being of patients with Crohn's disease has led to novel formula design and trials comparing two different forms of enteral nutrition. This systematic review aims to provide an update on the existing efficacy data for both corticosteroids versus enteral nutrition and for one form of enteral nutrition versus another for inducing remission of active Crohn's disease. OBJECTIVES: To evaluate the efficacy of exclusive enteral nutrition as primary therapy to induce remission in Crohn's disease and to examine the importance of formula composition on efficacy. SEARCH STRATEGY: Studies were selected using a computer-assisted search of the on-line bibliographic databases MEDLINE (1966-2000) and EMBASE (1984-2000), as well as the Science Citation Index on Web of Science. Additional citations were sought by manual search of references of articles retrieved from the computerized search, abstracts submitted to major gastroenterologic meetings and published in the journals: Gut, Gastroenterology, Journal of Pediatric Gastroenterology and Nutrition, and Journal of Parenteral and Enteral Nutrition, and from the reviewers' personal files or contact with leaders in the field. SELECTION CRITERIA: All randomized and quasi-randomized controlled trials involving patients with active Crohn's disease defined by a clinical disease activity index were considered for review. Studies evaluating the administration of one type of enteral nutrition to one group of patients and another type of enteral nutrition or conventional corticosteroids to the other group were selected for review. DATA COLLECTION AND ANALYSIS: Data were extracted independently by two reviewers and any discrepancies were resolved by rereading and discussion. For the dichotomous variable, achievement of remission, individual and pooled trial statistics were calculated as odds ratios (OR) with 95% confidence intervals (CI); both fixed and random effect models were used. The results for each analysis were tested for heterogeneity using the chi square statistic. The studies were separated into two groups: A. one form of enteral nutrition compared with another form of enteral nutrition and B. one form of enteral nutrition compared with corticosteroids. Subgroup analyses were conducted on the basis of clinical or disease criteria and formula composition. Sensitivity analyses were conducted on the basis of the inclusion of abstracts of studies not yet fully published, methodologic quality and by random or fixed effects models. MAIN RESULTS: In part A, of the 11 trials (one abstract) comparing different formulations of enteral nutrition ten compared one [or more (Middleton (a)1995)] elemental formulas to a non-elemental diet. The eleventh study (Akobeng 2000) compared two non-elemental diets differing only by glutamine enrichment in one group. This study was therefore not included in the primary analysis but was part of the subgroup analyses. Meta-analysis of nine studies which included 170 patients treated with an elemental diet and 128 patients treated with a non-elemental diet for active Crohn's disease demonstrated no significant difference among diet formulations [OR 1.15 (95% CI: 0.64, 2.08)]. Significant heterogeneity was not present [chi-square 9.77 (df=8)]. Subgroup and sensitivity analyses had no significant effect on the results. In part B, six trials (two abstracts) comparing enteral nutrition to steroid therapy met the inclusion criteria for review. Meta-analysis of four trials that included 130 patients treated with enteral nutrition and 123 treated with steroids yielded a pooled OR of 0.30 favouring steroid therapy (95% CI: 0.17, 0.52). Heterogeneity was not demonstrated [chi-square 0.43 (df=3)]. The risk difference calculated from this meta-analysis was 0.26, and the NNT (number of patients needed to treat with steroids rather than enteral nutrition to achieve one remission) was four. The same result was found in a sensitivity analysis that included abstracts. The inclusion of abstracts resulted in an increase in the number of participants to 150 in the enteral nutrition group and 142 in the steroid group but the meta-analysis yielded a similar result [OR 0.34 (95% CI: 0.20, 0.56)]. There were inadequate data from full publications to perform further subgroup analyses by age, disease duration and disease location. REVIEWER'S CONCLUSIONS: Corticosteroid therapy is more effective than enteral nutrition for inducing remission of active Crohn's disease as was found in past meta-analyses. There is no significant difference in the efficacy of elemental and non-elemental diets for induction of remission of Crohn's disease.

Adrenal Cortex Hormones↗

[Polymyositis associated with HIV immunodeficiency: clinical case and literature review].

A 33 year old female, suffering from HIV infection, presents with diffuse myalgia, generalized muscle weakness and painless dysphagia. An extensive work-up allows to diagnose an HIV-related polymyositis; while well-known, this entity is however rarely observed. Technetium-99m MDP skeletal scintigraphy shows multiple extra-osseous accumulations of the tracer: these observations, as well as the differential diagnoses of muscular involvement during HIV infection, are discussed.

Adult↗

Simplified algorithms for the estimation of 99Tcm-MAG3 clearance.

The aim of this study was to evaluate two formulae allowing the determination of MAG3 clearance by means of a single blood sample, namely Bubeck's formula and Russell's formula. As a first step, a simulation study was performed with the two single-sample algorithms to predict MAG3 clearance as a function of plasma concentration, using various times for blood sampling and various body surface areas. As a second step, a validation study on 47 adult patients with varying renal function allowed a clinical comparison between the reference technique, namely the multiple blood sample technique, and the two simplified techniques. The simplified algorithms were calculated using the fitted value at 44 min. In the simulation study, whatever the time of blood sampling or the level of correction introduced for body surface area, the results obtained by means of Bubeck's algorithm diverged significantly from those of Russell's algorithm, for low clearance values as well as for high clearance values. The curve of the differences between the two methods had a typical boomerang shape. In the clinical study, the difference between Russell's algorithm and the reference method was generally within 20 ml.min-1, with no systematic bias; with Bubeck's algorithm there was a marked underestimation, both in the low and high clearance ranges. We suggest Russell's single-sample method is the method of choice.

Adult↗

NORA: a simple and reliable parameter for estimating renal output with or without frusemide challenge.

The aim of this study was to evaluate a simple parameter describing renal output, namely NORA (normalized residual activity). We first compared, in a simulated model, different parameters of transit to an ideal standard; we then compared, in a clinical study, NORA and output efficiency. 123I-hippurate, 99Tcm-DTPA and 99Tcm-MAG3 plasma curves, each with two levels of renal clearance, were convoluted by means of different types of simulated retention functions, with different mean transit times. On the reconstructed renograms, several parameters reflecting renal transit were determined and compared with mean transit time. In a second step, in 33 patients, we compared output efficiency and NORA (i.e. the residual renal activity), normalized by the renal activity at 2 min. These two parameters were calculated at the end of the renogram, at the end of the frusemide test and after the micturition phase. In the simulated model, both output efficiency and NORA were only slightly influenced by the level of overall renal function. In the clinical study, a good correlation was found between output efficiency and NORA, whatever part of the study considered (renogram, frusemide test, post-voiding image). NORA is a simple and reliable parameter that allows quantification of renal output; it is almost independent of the level of renal function and can be used whatever the timing of the frusemide injection.

Adolescent↗

Inter-observer reproducibility of relative 99Tcm-DMSA uptake.

99Tcm-DMSA planar images of 49 randomly selected patients (10 adults, 39 children) were sent to 15 physicians at various centres in Belgium. They were asked to calculate, using their own routine program, the relative uptake (expressed as a percentage) of each kidney. The data were sent on disks formatted so that they could be read by all participants, using their own computer systems. For each scan, the inter-observer variability was expressed using the maximum difference and the standard deviation of left renal uptake. Left renal uptake measured by the 15 observers in the 49 patients was 29.0-72.0% (mean +/- s = 49.8 +/- 6.4%). The maximum differences in left renal uptake ranged between 1.7% and 12.0% (4.5 +/- 2.6%); however, the maximum difference did not exceed 8% in about 90% of the patients. The standard deviations of the individual left renal uptake were between 0.6 and 3.9 (1.3 +/- 0.8). The standard deviations were significantly higher in adults (mean standard deviation = 2.05) than in children (mean standard deviation = 1.12) (P < 0.001); this was probably related to the high background observed in three adults with severe renal impairment. Indeed there was a significant correlation (P < 0.001) between the standard deviation and both the signal-to-noise ratio and the degree of asymmetry between the right and left kidneys. The differences between right and left kidney uptake were systematically lower for some observers, suggesting an influence of the calculation programs.

Belgium↗

Should nuclear medicine physicians give the results of radioisotope examinations directly to patients?

Patients often ask for the results after a radioisotope procedure, which can make nuclear medicine physicians feel uncomfortable. In Belgium, nuclear medicine physicians are not supposed to disclose results directly to patients, but to send them to the referring physician. We undertook this work to determine the official rules and practical attitudes in other countries. An introductory letter and a questionnaire were sent to 103 eminent nuclear medicine specialists from 37 countries. Seventy responses (32 countries) were received. Official rules seemed to exist in only seven countries. Most of the respondents indicated that their attitude depended on the clinical situation and the results of the test. Many respondents emphasized that, while in some situations the results should be communicated directly to patients in order to initiate treatment rapidly, in other situations, such as cancer, the referring physician was better suited to disclose the results. The advantages and drawbacks of different attitudes are discussed. Practically and universally applicable rules are difficult to establish, but choosing one solution remains preferable to no standardized attitude at all. An official body, including the medical community, representatives of the population and legal experts, should define an official rule which should be widely communicated, stressing its advantages and drawbacks. In practice, all nuclear medicine physicians would have to do would be to stick to the rule.

Ethics, Medical↗

A multicenter trial on interobserver reproducibility in reporting on 99mTc-DMSA planar scintigraphy: a Belgian survey.

UNLABELLED: Conflicting opinions have been expressed regarding reproducibility in 99mTc-dimercaptosuccinic acid (DMSA) planar renal image interpretation. The purpose of this investigation was to determine the level of interobserver variability among a large group of Belgian nuclear medicine physicians who evaluated a randomly selected series of DMSA planar scintigraphic examinations performed on children and adults. METHODS: All Belgian nuclear medicine centers (n = 82) were invited to participate in a reproducibility study on 99mTc-DMSA scintigraphy. 99mTc-DMSA scans obtained on 10 adults and 40 children were randomly selected from the databases of 2 hospitals. Those participating in this investigation (65 centers = 79%) received a series of computer disks containing 50 99mTc-DMSA studies. To avoid potential problems related to unfamiliar display, the disks were formatted to be interpretable using the participants' own computer systems. Each participant was then free to use his or her usual display (hard copies, contrast enhancement, color scale, gray scale, and so forth). For each kidney, the observers had to choose between the following answers: normal, abnormal, equivocal, and lack of quality. RESULTS: Forty-two responses were obtained from a wide variety of institutions and from observers with different levels of experience in interpreting 99mTc-DMSA scintigraphy. Altogether, the following data were obtained: 60.8% normal, 25.2% abnormal, 7.0% equivocal, and 3.2% lack of quality. The median percentage of agreement (overall reproducibility) for the 42 observers was 92%. When the results of all 42 observers were compared, the median agreements on normality and abnormality were 93.5% and 90.5%, respectively. In a small number (n = 4) of kidneys, reproducibility was poor and ranged from 51% to 70%. Except for 2 outliers, all observers had almost the same level of performance. CONCLUSION: A large number of Belgian nuclear medicine physicians participated in evaluating a large randomly selected sample of 99mTc-DMSA studies, and excellent interobserver agreement was found.

Adolescent↗

[Should we give the examination results to the patients?].

Immediately after medical imaging procedures, patients often ask for the results of their examination. Such a request is very uncomfortable for the physician performing the examination, who usually does not know the whole medical file, the psychological status of the patient, how he is informed about his illness, etc. By the means of a questionnaire we asked belgian nuclear medicine physicians about the frequency of such situations and about their practical attitude. 204 questionnaires were sent; we received 119 answers (58%) after a 6 weeks delay. In more than 85% of the cases, this situation occurs regularly, and more than 50% of the participating physicians encounter the problem in more than 20% of the cases. Less than 10% of the participating physicians never give any result to the patient asking for it, while more than 20% always give it. Most of the physicians takes into account the clinical situation of the patient. Unfortunately, the official guidelines do not help to clarify the situation. This work confirms that physicians who perform diagnostic procedures frequently encounter difficulties in patients information. It would be necessary that all people who are concerned by this problem collaborate in order to define a clear and accurate attitude which would be easily applicable in our daily clinical practice.

Attitude of Health Personnel↗

Evolution of single kidney glomerular filtration rate in urinary tract infection.

The aim of this study was to evaluate renal function during the acute phase of symptomatic urinary tract infection and the changes observed several months later. Overall glomerular filtration rate (GFR) as well as single kidney GFR (SKGFR) were calculated using the combination of a left/right uptake ratio obtained from technetium 99m-dimercaptosuccinic acid (DMSA) scintigraphy and 51chromium-EDTA plasma clearance. Forty-four patients with obvious unilateral or bilateral DMSA abnormalities were studied. In patients with unilateral lesions, both the overall GFR and the SKGFR were significantly higher during the acute phase of infection than several months later, on the abnormal side as well as the normal side. The relative percentage uptake was lower on the abnormal side than the normal side, obviously due to loss of functional parenchyma. This percentage increased significantly during the recovery phase, reflecting the total or partial healing of the renal lesions, despite the decrease of the corresponding SKGFR. However, during both the acute and the recovery phase, the relative percentage uptake of the abnormal kidney was in the normal range and often close to 50%. In patients with bilateral lesions, no significant changes were observed between the acute phase and the recovery phase.

Adolescent↗

Relative 99mTc-MAG3 renal uptake: reproducibility and accuracy.

UNLABELLED: The aim of this study was to estimate the reproducibility and accuracy of 99mTc-mercaptoacetyltriglycine (MAG3) relative percentage uptake. METHODS: Reproducibility was evaluated on healthy volunteers who were submitted twice to a 99mTc-MAG3 renographic study, which used different uptake algorithms, different background corrections and different time intervals. Accuracy was evaluated in a group of patients with symmetrical or asymmetrical relative renal function, who underwent both 99mTc-dimercaptosuccinic acid (DMSA) and 99mTc-MAG3 studies, using the DMSA relative percentage uptake as a reference. RESULTS AND CONCLUSION: The methods that combined the best reproducibility and accuracy for estimating 99mTc-MAG3 left-to-right uptake ratio were the integral method, with subrenal or perirenal background correction, and the Patlak-Rutland plot. The use of the integral method without background correction introduced a systematic bias, whereas the slope method resulted in high variability. Therefore these methods cannot be recommended.

Adult↗

[Overall and separate clearance--renography with and without captopril].

The present work briefly describes the radionuclide renal functional tests available for the work up of adult hypertensive patients. The use and specific indications of the different techniques and radiopharmaceuticals are reviewed and summarized. A special attention is given to captopril enhanced renograms: these non invasive procedures contribute to the diagnosis of renovascular hypertension.

Adult↗

Overall and single-kidney clearance in children with urinary tract infection and damaged kidneys.

UNLABELLED: The overall and single-kidney clearance in children with acute urinary tract infection was investigated retrospectively using the combination of the relative 99mTc-dimercaptosuccinic acid (DMSA) uptake and the 51Cr-ethylenediaminetetraacetic acid clearance. METHODS: There were 180 patients with both normal kidneys, 56 with clear unilateral abnormalities on DMSA scintigraphy and 11 with two abnormal kidneys. Half of the patients were younger than 2 y, and because of the progressive maturation of the renal function, they were not considered in the analysis of the absolute overall and single-kidney clearance; nevertheless, they were included in the analysis of the relative DMSA percentage uptake. RESULTS: When only one kidney was affected on DMSA scintigraphy, the clearance of the affected kidney was lower than on the normal side and often abnormally low. In these unilaterally affected kidneys, contralateral compensation mechanisms tended to occur, resulting in preservation of overall clearance. This compensation was probably not present only on the contralateral side. On the abnormal side, the clearance was normal in about half of the cases, probably because of intrarenal compensation occurring in regions not damaged by the infection. In addition to these compensation mechanisms, hyperfiltration was probably present in many cases of acute urinary tract infection with intact or unilaterally damaged kidneys.

Acute Disease↗