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M Wiesel

Publications and source records attributed to M Wiesel.

At least 19 recordsLinked to original sources

EAU guidelines on renal transplantation.

OBJECTIVES: To produce a guidelines text, on behalf of the European Association of Urology, providing insights in the issues surrounding renal transplantation. METHOD: A group of international experts in renal transplantation carried out a non-structured literature review on available medical databases and urological literature. RESULT: A guideline text is presented providing an overview of key issues involved in the patients' management such as assessment of donors, pre-transplant evaluation, techniques, management, post-transplant care, etc. CONCLUSION: The current text represents a consensus statement developed by a group of international experts in renal transplantation.

Graft Rejection↗

[Consumption of hand-hygiene products in health establishments in the west of France].

OBJECTIVES: The study had for aim to investigate hand hygiene product use in French hospitals between 2000 and 2003. DESIGN: A questionnaire was sent in 2002 and 2 more in 2003 and 2004 (for 2000 to 2003) requiring data on type of hospital, number of beds, staff members, admissions and patient-day, litres of mild soap, antiseptic soap and alcohol-based rub used and price per litre. Indices were calculated accordingly. RESULTS: 574 hospitals answered over the 4 year period (average 143 per year) representing an average of 50 000 beds/year, 80 000 full-time staff positions, 1.2 million admissions and 16 millions patient-days. The median consumption of mild soap was 3.8 l per bed, 2.7 l per staff member, 2.4 l per 100 admissions, and 10.6 ml per patient-day. The median consumption of antiseptic soap was 1 l per bed, 0.8 l per staff member, 4.8 l per 100 admissions, and 3.2 ml per patient-day. The median consumption of alcohol-based rub (HAS) was 0.3 l per bed, 0.3 l per staff-member, 1.5 l per admission, and 0.9 l per patient-day. Between 2000 and 2003, HAS use significantly increased from 69 to 88% (a relative increase of 31%) and the median consumption increased from 0.5 ml to 1.5 ml per patient-day. 370 fully completed grids gave a number of 7 opportunities per patient-day with less than 1 for HAS. CONCLUSION: The best indicator for an infection control practitioners is the quantity of alcohol-based solution in ml/patient-day and HAS per patient-day is the reference.

Alcohols↗

Pediatric renal transplantation and the dysfunctional bladder.

We retrospectively reviewed our long-term experience with pediatric renal transplantation into a dysfunctional lower urinary tract to evaluate graft survival, function, and special urological complications. Between 1967 and March 2000, a total of 349 renal transplantations were performed in children younger than 18 years. Malformations of the lower urinary tract were the reasons for end-stage renal failure in 66 children (18.6%). The cause of urinary tract disorders included: meningomyelocele connected with neuropathic bladder (n = 4 transplantations); prune belly syndrome (n = 5 transplantations); VATER association (n = 2 transplantations); posterior urethral valves (n = 27 transplantations); and vesico-uretero-renal reflux (n = 28 transplantations). The majority of the patients underwent surgical interventions to preserve renal function or to prepare renal transplantation. The 1- and 5-year graft survival rate was evaluated with special reference to the underlying disease. The 1-year graft survival rate in all children with lower urinary tract malformations was 83.3%, compared with 88% for all children. In those children with vesico-ureteral reflux, it was 92.8% and in the children with Vater association and prune belly syndrome, it was 85.7%. One graft was lost in the children who had neurogenic bladder, so the 1-year graft survival rate was 75%. The worst 1-year graft survival rate was obtained for boys who had posterior urethral valves (1-year graft survival rate: 74%; 5-year graft survival rate: 62.9%). Concerning the 5-year graft survival rate, it was 70% for all children with malformations of the urinary tract. The best rate was obtained for children with reflux in the native kidneys (78.5%), followed by those with VATER association and prune belly syndrome. As an additional child with neurogenic bladder lost his graft, the 5-year graft survival rate was 50%. Pediatric renal transplantation into a dysfunctional bladder can be connected with high urological complication rates which may contribute to worse graft survival. The 1- and 5-year graft survival rate in children with malformations of the lower urinary tract is worse than in children without bladder dysfunction. We regarded a striking difference between graft survival and the urological disorders which led to renal insufficiency. We obtained the worst graft survival rates in children with posterior urethral valves which are usually connected with bladder emptying problems and dysfunctional voiding. Potential pediatric transplant recipients must be classified according to pathophysiological as well as anatomical abnormalities of the urinary tract and all urological problems have to be solved prior to transplantation. At our center, living donors are favored to plan transplantation of these children properly.

Adolescent↗

Differential early posttransplant cytokine responses in living and cadaver donor renal allografts.

BACKGROUND: Differences in early posttransplant immunologic responses between living donor (LDT) and cadaver donor transplant (CDT) recipients have not been thoroughly studied. This is the first study comparing lymphocyte subpopulations and plasma levels of different cytokines, soluble cytokine receptors, cytokine receptor antagonists, and neopterin during the first 2 posttransplant weeks. PATIENTS AND METHODS: Lymphocyte subpopulations (CD3, CD4, CD8, CD16, CD19, and CD25) and plasma levels of soluble (s) interleukin(IL)-1 receptor antagonist (RA), IL-2, sIL-2R, IL-3, IL-4, IL-6, sIL-6R, IL-8, IL-10, transforming growth factor-beta(2), tumor necrosis factor-alpha, interferon-gamma, and neopterin were studied in 52 CDT and 33 LDT recipients 1 to 2, 4 to 6, and 8 to 10 days after transplantation. RESULTS: The most impressive finding was a consistently higher neopterin plasma level in CDT than LDT recipients. Although plasma neopterin decreased during the second posttransplant week in both groups (CDT, P = 0.0001; LDT, P = 0.001), the difference in plasma neopterin levels 8-10 days after transplantation was highly significant (P = 0.005). In contrast, LDT had consistently higher sIL-1RA plasma levels during the first 2 posttransplant weeks. Whereas sIL-1RA plasma levels decreased in both groups during the first posttransplant week (CDT, P = 0.001; LDT, P = 0.005), they increased during the second posttransplant week in LDT (P = 0.02) but remained stable and low in CDT recipients. Eight to ten days after transplantation, the difference was highly significant (P = 0.002). CONCLUSION: These data suggest that transplantation of CDT is associated with strong monocyte-macrophage activation with consistently high neopterin plasma levels, whereas the effect of inflammatory cytokines seems to be down-regulated in LDT recipients by an increased release of antiinflammatory sIL-1RA.

Adolescent↗

[Vacuum sealing of extensive wound healing disorders after kidney transplantation].

With the introduction of mycophenolate mofetil (MMF) in renal transplantation, acute rejection episodes diminished and short-term graft survival improved. Better graft outcome, however, is followed by several surgical complications attributed to MMF. Patients with risk factors (adiposity, diabetes mellitus, advanced age) show an increased rate of healing by second intention. We treated two patients with the vacuum sealing technique so that after 15 days a secondary suture became possible in each case. To date the vacuum sealing technique has been used mainly in traumatology, abdominal surgery, surgery for acute infections of soft tissue and bone, and problem wounds with reduced wound-healing capacity (chronic leg ulcer). This article presents two cases of successful application of the vacuum sealing technique in renal transplantation after prolonged wound healing.

Body Mass Index↗

Pre-transplant Th1 and post-transplant Th2 cytokine patterns are associated with early acute rejection in renal transplant recipients.

In this retrospective study, we tried to define pre- and post-transplant immunological parameters that identify patients at risk for early acute rejection. Lymphocyte subpopulations and plasma levels of cytokines and neopterin were determined pre- and post-transplant in 32 renal transplant recipients with biopsy-proven early acute graft rejection. Recipients without early acute rejection served as controls. High pre-transplant interferon-gamma (IFN-gamma) plasma levels (p = 0.006), consistently high levels of neopterin early post-transplant (p = 0.008), a post-transplant switch from a Th1 to a Th2 cytokine pattern with decreasing IFN-gamma (p = 0.02), low CD8+ lymphocyte counts (p = 0.006) and consistently high CD19+ B lymphocyte counts were associated with acute rejection. Our data suggest that patients with a pre-transplant Th1 and an early post-transplant Th2 cytokine pattern are pre-disposed for early acute rejection.

Adult↗

Preoperative evaluation of living renal donors: value of contrast-enhanced 3D magnetic resonance angiography and comparison of three rendering algorithms.

The aim of this study was to assess the value of contrast-enhanced three-dimensional MR angiography (CE 3D MRA) in the preoperative assessment of potential living renal donors, and to compare the accuracy for the depiction of the vascular anatomy using three different rendering algorithms. Twenty-three potential living renal donors were examined with CE 3D MRA (TE/TR=1.3 ms/3.7 ms, field of view 260-320x350 mm, 384-448x512 matrix, slab thickness 9.4 cm, 72 partitions, section thickness 1.3 mm, scan time 24 s, 0.1 mmol/kg body weight gadobenate dimeglumine). Magnetic resonance angiography data sets were processed with maximum intensity projection (MIP), volume rendering (VR), and shaded-surface display (SSD) algorithms. The image analysis was performed independently by three MR-experienced radiologists recording the number of renal arteries, the presence of early branching or vascular pathology. The combination of digital subtraction angiography (DSA) and intraoperative findings served as the gold standard for the image analysis. In total, 52 renal arteries were correspondingly observed in 23 patients at DSA and surgery. Other findings were 3 cases of early branching of the renal arteries, 4 cases of arterial stenosis and 1 case of bilateral fibromuscular dysplasia. With MRA source data all 52 renal arteries were correctly identified by all readers, compared with 51 (98.1%), 51-52 (98.1-100%) and 49-50 renal arteries (94.2-96.2%) with the MIP, VR and SSD projections, respectively. Similarly, the sensitivity, specificity and accuracy was highest with the MRA source data followed by MIP, VR and SSD. Time requirements were lowest for the MIP reconstructions and highest for the VR reconstructions. Contrast-enhanced 3D MRA is a reliable, non-invasive tool for the preoperative evaluation of potential living renal donors. Maximum intensity projection is favourable for the processing of 3D MRA data, as it has minimal time and computational requirements, while having similar or superior accuracy for the depiction of vessel anomalies or pathology compared with VR and SSD, respectively.

Algorithms↗

[Laparoscopic liver donor nephrectomy. Personal experiences and review of the literature].

Despite improved success rates, the number of kidney transplantations in Germany in the last few years has stagnated, resulting in increasing waiting lists of patients on dialysis. In Germany, only 16.7% of kidney transplantations are living-donor nephrectomies, representing a relatively low rate compared to other countries (The Netherlands 28%, Sweden 35%). Since April 1998, we have performed ten retroperitoneoscopic living-donor nephrectomies (six left, four right side). The mean operating time was 216 min (155-290) with minimal blood loss. No intraoperative complications were observed. Warm ischemia time amounted to a mean of 4 min (2-7). The mean cold ischemia time was 165 min (76-290). Postoperative hospital stay of the donors was 6 days (4-10). All transplants functioned immediately; mean serum creatinine dropped from initially 8.0 mg/dl (5.3-11.5) on day 1 to 1.4 mg/dl (0.9-1.6) 3 months after surgery. This did not differ from previously operated open donor nephrectomies. An analysis of the literature included data of 4240 patients from 25 publications between 1980 and 2000 reporting on either open or laparoscopic living donor nephrectomies.

Adult↗

Renal transplantation in small children--a comparison between surgical procedures.

OBJECTIVES: Renal transplantation is the therapy of choice for patients with end-stage renal failure. From the surgical point of view, small children remain a challenging patient group. METHODS: We report our experience with 61 consecutive kidney transplantations in small children aged < or =6 years. Outcome and graft survival rates were presented with special reference to the surgical procedure used to perform the renal transplantation. RESULTS: Of the 31 renal grafts, placed into the fossa iliaca (group 1), 8 grafts were lost shortly after transplantation due to a vascular complication (5 venous thromboses and 3 arterial thromboses). Six allografts were lost because of acute rejection. All in all, the 1- and 5-year graft survival rate in this group was 55.8% (p = 0.0106)/51.6% (p = 0.0134), respectively. Thirty grafts were placed retroperitoneally, using the aorta and the distal caval vein to perform end-to-side anastomoses (group 2). One graft was lost because of a venous thrombosis 6 weeks following transplantation, 3 further grafts were lost during the 1st year after transplantation due to acute rejection. The 1- and 5-year graft survival rate in that group was 86.6% (p = 0.0106)/83.3% (p = 0.0134), respectively. Comparing the 1-year graft survival rates of the two patient groups with special reference to vascular complications, we observed a 1-year graft survival rate of 74.2% (group 1) versus 96.6% (group 2; p = 0.026). CONCLUSIONS: Our results on kidney transplantation in small children have considerably improved with the consistent use of the aorta and the distal caval vein to perform vascular anastomoses. The number of vascular complications following renal transplantation decreased, and especially for very small children the retroperitoneal placement of the graft is a safe, feasible surgical procedure that should be performed whenever possible.

Child↗

Atherosclerotic complications after renal transplantation.

Death with functioning graft, the most frequent cause being cardiac death, continues to be the most frequent cause of long-term graft loss. The risk of cardiovascular death in the transplanted patient is lower than in patients with other modalities of renal replacement therapy, but continues to be substantially higher than in the general population. Amongst the factors predicting patient and graft survival are hypertension, dyslipidemia, smoking and possibly hyperhomocysteinemia. It is concluded that lowering of blood pressure to levels far lower than levels accepted in the past, more widespread administration of statines, cessation of smoking and possibly administration of folate should reduce cardiovascular mortality and possibly also influence chronic allograft vasculopathy.

Arteriosclerosis↗

Impaired bone metabolism following augmentation cystoplasties in growing rats.

OBJECTIVE: The aim of this study was to evaluate the possible risk of impaired bone metabolism following augmentation cystoplasties with different gastrointestinal segments. METHOD: 60 young rats underwent augmentation cystoplasties using gastric, ileal or sigma segments, or sham operations. An additional group undergoing sigma-cystoplasty received the bisphosphonate ibandronate to inhibit osteoclast-mediated bone resorption. Bone mass in the lumbar spine and tibia was analyzed monthly by in vivo densitometry. Bone turnover was assessed monthly using current bone metabolism markers for a period of 16 weeks. Bone ashing and serum analyses of the osteotropic hormones parathyroid hormone (PTH), and 25-OH vitamin D3 were performed at study conclusion. RESULTS: Following ileocystoplasty, reduced bone mineral density (BMD) was seen throughout the observation period; this was pronounced in the trabecular bone. The decline in BMD was associated with decreased serum 25-OH vitamin D3 levels. Following sigmacystoplasty, bone calcium content was significantly decreased; this could be prevented by ibandronate. No skeletal changes occurred in the gastrocystoplasty group. Serum pH was not altered in any group, and markers of bone resorption indicated normal bone resorption rates. CONCLUSION: There is a significant correlation between impaired bone metabolism and the type of segment used for bladder augmentation. While the use of the ileum (and probably the colon too) causes osteopenia, gastrocystoplasties seem to have little influence on bone turnover.

Absorptiometry, Photon↗

[Radiodiagnosis following kidney transplantation].

Diagnostic imaging after renal transplantation is of high importance in the differential diagnosis of peri- and postoperative complications. Sonography with color duplex imaging is the method of choice in the diagnosis of acute transplant rejection. MRI is an additional method in the diagnosis of transplant dysfunction especially in diagnosis of perirenal fluid collections. MR angiography and MR urography are noninvasive diagnostic modalities with the potential to replace angiography and pyelography. Angiography, complemented by carbon dioxide angiography, still is the gold standard in the diagnosis of transplant artery stenosis.

Angiography↗

P-glycoprotein expression is not a useful predictor of acute or chronic kidney graft rejection.

Because of the role of P-glycoprotein (P-gp) in multidrug resistance (MDR), it has been suggested that P-gp might play a role in acute and chronic rejection after organ transplantation. The purpose of the present work was to investigate a possible relationship between graft outcome and P-gp expression on peripheral mononuclear cells of renal transplant recipients. We determined P-gp expression in 27 patients with long-term, stable graft function (ST) and in 15 patients with chronic deterioration of graft function (CR). In addition, 40 patients were studied prior to, and at intervals after, transplantation with 21 healthy individuals serving as controls. P-gp values were highest in healthy controls and in ST patients. We found no correlation between P-gp values and acute rejection. CR patients tended to have lower levels of P-gp expression. Our results contradict the opinion that an overexpression of P-gp induces acute or chronic rejection by inhibiting the efficacy of immunosuppressive treatment.

ATP Binding Cassette Transporter, Subfamily B, Mem↗