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J N Ijzermans

Publications and source records attributed to J N Ijzermans.

At least 19 recordsLinked to original sources
PubMed2004

[Cross-over transplantation; a new national program for living kidney donations].

In the Netherlands, cross-over kidney transplantation has been introduced as an extra option in the living kidney donation programme. In cross-over transplantation, patients who cannot be given their own partner's kidney for immunological reasons are given a kidney from the partner of another patient in exchange for a kidney from their own partner. There is no difference in the medical indications and contraindications between direct and indirect living donation. There are no ethical obstacles since the net gain for the two couples is no different from that of direct living kidney donation and because the exchange takes place on the basis of equality. One should be aware that the extra possibilities may result in more psychological pressure on potential donors. It is important that the donation procedures start at the same moment and that the wishes of patients and donors for anonymity be preserved. A successful cross-over kidney transplantation programme requires a large pool of donors and patients. Therefore, this has been organised in a national programme. The Dutch Transplantation Foundation is responsible for the allocation of cross-over kidneys. Organ trade will thus be impossible. The seven Dutch centres for kidney transplantation have developed a protocol.

Female↗
PubMed2001

Reassuring effect of pravastatin on natural killer cell activity in stable renal transplant patients.

BACKGROUND: Administration of pravastatin soon after transplantation successfully lowers cholesterol levels, whereas a reduced number of acute rejection episodes is accompanied by a decrease in natural killer (NK) cell activity. As a consistent low NK cell activity caused by pravastatin might impair tumor surveillance leading to cancer, we studied the effect of pravastatin on NK cell activity in stable renal transplant patients. METHODS: From 14 cyclosporine (CsA)-treated and 11 azathioprine (AZA)-treated patients with hypercholesterolemia, more than 1 year after kidney transplantation, we determined NK cell number and cytotoxic activity before, and at 6 and 12 weeks after, initiating pravastatin treatment. Additionally, cholesterol levels and liver and kidney function parameters were assessed. RESULTS: During pravastatin treatment, total cholesterol and low-density lipoprotein-cholesterol levels decreased significantly in both patient groups. In the CsA group, the number and cytotoxic activity of the NK cells at 12 weeks after institution of pravastatin was in the same range as before pravastatin. Additionally, in the AZA group, pravastatin did not influence the number of NK cells. However, in the AZA group, both the number of NK cells and their cytotoxic activity were significantly (<0.002) lower compared to the values in the CsA group. CONCLUSIONS: In contrast to previous reports on decreased NK cell cytotoxicity caused by pravastatin treatment early after transplantation, we cannot confirm these results in stable kidney recipients. In our hands, NK cell cytotoxicity during pravastatin treatment was within the same range as in the absence of pravastatin. Thus, in view of the potential role of NK cells in tumor surveillance, these data are reassuring.

Anticholesteremic Agents↗
PubMed2001

Cold ischemia augments allogeneic-mediated injury in rat kidney allografts.

BACKGROUND: Some clinical studies demonstrate that kidney grafts with prolonged cold ischemia experience early acute rejection more often than those with minimal ischemia. The mechanism, however, is putative. Therefore, the aim of this study was to unravel the impact of ischemia on the immune response in rat kidney allografts compared with that in isografts. METHODS: To induce ischemic injury, donor kidneys were preserved for 24 hours in 4 degrees C University of Wisconsin solution before transplantation. No immunosuppression was administered. The histomorphology according to the BANFF criteria for acute rejection and infiltrating cells were assessed at days 1, 2, 3, 4, 6, and 8 post-transplantation. RESULTS: In allografts, exposure of the kidney to ischemia led to a significantly earlier onset of interstitial cell infiltration and tubulitis compared with nonischemic allografts. The BANFF score of interstitial cell infiltration was 1 +/- 0 vs. 0.25 +/- 0.29 at day 3 and 2 +/- 0 vs. 1.25 +/- 0.25 at day 4. In contrast, in isografts, the effect of ischemia on the histology was not significant. From day 6, the histologic differences between ischemic and nonischemic grafts disappeared. Ischemia led to a more intense expression of P-selectin (day 1), intercellular adhesion molecule-1 (ICAM-1; day 2), and major histocompatibility complex (MHC) class II on endothelium and proximal tubular cells (day 2) in both allografts and isografts. Concurrently with the up-regulated ICAM-1 and MHC expression, significantly more CD4(+) cells and macrophages infiltrated the ischemic allografts at days 2 and 3 and the ischemic isografts at day 4. Importantly, the influx of these cells after ischemia was significantly greater in allografts than in isografts. CONCLUSIONS: Cold ischemia augments allogeneic-mediated cell infiltration in rat kidney allografts. The earlier onset of acute rejection in 24-hour cold preserved allografts may be prevented by better preservation or treatment using tailored immunosuppression.

Animals↗
PubMed2001

Long-term graft survival after urological complications of 695 kidney transplantations.

PURPOSE: We ascertain the incidence, management and long-term outcome of early urological complications requiring surgical exploration in kidney transplantation. MATERIALS AND METHODS: Data of 695 consecutive kidney transplantations performed between January 1985 and January 1997 were assessed in regard to urological complications that occurred within 1 year after transplant. A computerized database was used to analyze graft recipient characteristics, the implantation procedure, complications and outcome in select patients and all those who underwent transplant during the same period. In the noncomplication group sufficient data for evaluation was available for 556 patients. We performed the Cox proportional hazards analysis with overall graft failure, graft failure or death as end points of observation. RESULTS: Overall, 42 (6.0%) patients required revision of vesicoureteral anastomosis. Complications were identified after a median of 6 days (range 0 to 135). The primary reconstruction technique was extravesical in 64% and transvesical in 33% of patients, including 1 that involved ureteral Bricker anastomosis. Obstruction and/or leakage at vesicoureteral anastomosis accounted for 69% of urological complications. Revision was performed with a number of different reconstruction techniques. A second revision was required in 16.7%. Mean followup after primary transplant was 9.1 years (range 3.2 to 15). Multivariate analysis showed that surgical treatment of urological complication during year 1 after kidney transplantation did not increase the risk of overall graft failure, graft failure or death. CONCLUSIONS: Our results indicate that long-term graft survival is not affected by a surgically treated urological complication.

Adult↗
PubMed2001

Ureteroneocystostomy contributes to late functional and morphological changes in rat kidney transplants.

PURPOSE: We investigated whether the surgical technique used to reconstruct the ureter has an impact on the late function of kidney transplants by comparing ureteroneocystostomy and ureteroureterostomy. To rule out alloantigeneic mediated effects on late graft dysfunction kidney transplants were performed in a syngeneic model. MATERIALS AND METHODS: Rat kidney isografts were transplanted with simultaneous ureteroneocystostomy or ureteroureterostomy. Unilaterally nephrectomized rats served as controls. Eight weeks after transplantation intrapelvic pressure was measured during baseline diuresis, and after intravesical and intrapelvic infusion. Albuminuria was determined monthly until sacrifice at week 52. Histomorphological analysis included the degree of glomerulopathy, tubular atrophy, interstitial fibrosis and intimal hyperplasia. CD4+- and CD8+ T cells, and macrophages were identified using immunohistochemical testing. RESULTS: Eight weeks after transplantation intrapelvic pressure during baseline diuresis and after intrapelvic infusion was significantly increased in rats with ureteroneocystostomy versus those with ureterostomy and unilateral nephrectomy, whereas intravesical infusion did not change the pressure in any group. During followup albuminuria after ureteroureterostomy did not differ from that after unilateral nephrectomy. In contrast, albuminuria significantly increased after ureteroneocystostomy from week 36 onward. At week 52 the ureter and kidney after ureteroureterostomy and unilateral nephrectomy had a normal appearance, whereas all ureters were dilated after ureteroneocystostomy. Nevertheless, 6 of the 8 kidneys in the ureteroneocystostomy group had a normal appearance. However, histomorphological findings in rats with transplants and ureterovesical anastomosis demonstrated significantly more interstitial fibrosis, CD8+ T cells and macrophages than isografts ureteroureterostomy. CONCLUSIONS: As a surgical technique for restoring the urinary tract after kidney transplantation, ureteroneocystostomy contributes to the development of long-term functional and histological renal changes. Partial obstruction may be the cause of this renal impairment.

Albuminuria↗
PubMed2000

[Treatment of non-resectable liver tumors with percutaneous interstitial laser coagulation while interrupting blood circulation to the liver].

OBJECTIVE: To evaluate, in patients with hepatocellular carcinoma or colorectal carcinoma disseminated to the liver, treatment with interstitial laser coagulation (ILC) during temporary occlusion of vascular inflow in the liver: feasibility, complications and initial tumour response. DESIGN: Prospective, descriptive. METHODS: Patients were included if their tumours were surgically irresectable and smaller than 4 cm in diameter and did not exceed a number of 3. ILC was performed under general anaesthesia, basically via a percutaneous approach. Vascular inflow was occluded during laser treatment. Twenty-four hours after ILC a triphasic spiral CT was performed to assess the result of the treatment. RESULTS: In 10 patients 14 hepatic tumours were lasered in 12 treatment sessions (10 percutaneous and 2 at laparotomy). After 5 treatment sessions, complications were observed of which pain at the insertion site of the catheters was the most frequent. For 6 out of the 10 patients with percutaneous procedures, discharge was within 24 hours after ILC. Nine out of the 14 tumours (65%) were completely coagulated. CONCLUSION: ILC with vascular inflow occlusion is a safe and feasible technique that can be performed during a short hospital stay. Initial tumour response is 65% and these results justify determination of duration of response in a larger group of patients.

Aged↗
PubMed2000

The influence of cholesterol on mortality after transplantation is age dependent.

There is still no consensus on the treatment of elevated serum cholesterol in patients with a renal transplant. In the general population treatment is age dependent. We studied the influence of serum cholesterol 1 year after transplantation in all 676 recipients of a kidney graft transplanted in Rotterdam that survived and functioned for at least 1 year. The other variables included in this analysis are: donor and recipient age and gender, original disease, race, number of HLA A and B mismatches, number of previous transplantations, postmortal or living related transplantation and transplantation year. At 1 year after transplantation the following variables were included: serum cholesterol, serum creatinine, proteinuria and hypertension. In the Cox proportional hazards analysis, serum cholesterol at 1 year after transplantation turned out to be an important, independent variable influencing patient failure. The influence was linear but there was interaction with recipient age. The negative influence of serum cholesterol on the RR for patient failure decreased with increasing recipient age. For example, the proportional increase in RR of a 20-year-old with a serum cholesterol of 12 mmol/l compared with that of a cholesterol of a patient with serum cholesterol of 6 mmol/l was 6. In a 60-year-old with a cholesterol of 12 mmol/l the proportional increase in RR was only 1.2 compared with a contemporary with a cholesterol of 6 mmol/l. Serum cholesterol levels have an independent influence on patient failure. The RR is influenced by recipient age, so that the negative effect of increasing cholesterol levels in the elderly is overruled by the RR of age and disappears.

Adult↗
PubMed1999

Late graft dysfunction after prolonged cold ischemia of the donor kidney: inhibition by cyclosporine.

BACKGROUND: The present study was devised to elucidate the influence of prolonged cold ischemia on the development of chronic transplant dysfunction (CTD) in kidney isografts (Brown Norway-->Brown Norway; BN-->BN) and in kidney allografts (BN-->Wistar Agouti/ Rij [WAG]) under temporary cyclosporine (CsA) therapy. METHODS: To induce ischemic injury, BN donor kidneys were preserved for 24 hr in 4 degrees C University of Wisconsin solution before transplantation. Renal function (proteinuria), histomorphology according to the BANFF criteria for CTD, and infiltrating cells were assessed. Grafts were examined both early at days 2, 3, 6, and 10, and late at week 26 (allografts) or at week 52 (isografts). RESULTS: Nonischemic isografts preserved a normal function and morphology. Ischemic isografts developed a progressive proteinuria over time and demonstrated significantly more glomerulopathy with macrophage (Me) infiltration and intimal hyperplasia than nonischemic controls at week 52. During the initial 10 days, there was an increased infiltration of MHC class II+ cells, predominantly CD4+ cells and Mphi, coinciding with up-regulated intercellular adhesion molecule-1 expression. CsA treatment in ischemic isografts inhibited infiltration of MHC II+ cells in the early stage, which was accompanied by significantly less renal damage at week 52 compared with untreated controls (proteinuria: 59+/-8 vs. 134+/-19 mg/24 hr; BANFF score: 2.8+/-0.4 vs. 4.3+/-1.0). Under CsA therapy, 24-hr cold ischemia of the allograft affected neither the onset or progress of proteinuria, nor the histomorphology (BANFF score: 7.8+/-2.4 vs. 7.3+/-1.9). In both ischemic and nonischemic allografts, intercellular adhesion molecule-1 expression and mononuclear cell infiltration (CD4, CD8, Mphi was abundantly present during the first 10 days and function deteriorated rapidly. CONCLUSIONS: Prolonged cold ischemia plays a role in the induction of CTD, but its deleterious effect can be successfully inhibited by CsA. Therefore, the alloantigeneic stimulus is the overriding component in the multifactorial pathogenesis of CTD.

Adenosine↗
PubMed1999

[Immunology in clinical practice. XXIII. Xenotransplantation].

Currently xenotransplantation is being discussed on national and international levels as a possible solution to tranplantation waiting lists, in view of the lack of alternative therapies. In recent years, enormous progress has been made in the area of immunology, especially concerning hyperacute rejection. However, long-term survival is still fiction due to relatively unknown, sequential rejection processes. Moreover, it remains questionable if xenogeneic organs will function physiologically, especially if they are metabolically complex. A third problem is the possible infectious risk of xenotransplantation to the patient and the population. Regarding this hazard, various committees and policy reports demand clarity first before the initial clinical transplantations become fact. In the Netherlands, the government largely adopted an identical advice by the Health Council. Artificial organs and cloning developments indicate that xenotransplantation might merely be an intermediate station in the route to develop adequate treatment for patients with organ failure.

Animals↗
PubMed1999

[Laparoscopic donor nephrectomy for kidney transplants from living family members: good preliminary results].

OBJECTIVE: Evaluation of safety and technical feasibility of laparoscopic live donor nephrectomy. DESIGN: Descriptive. METHOD: The per- and postoperative results were analysed of 15 patients subjected to laparoscopic live donor nephrectomy in the Erasmus Medical Centre Rotterdam, Dept. of General Surgery, the Netherlands. Both left and right nephrectomy were performed via the transperitoneal route. The kidney was removed via a subumbilical incision. RESULTS: Laparoscopic donor nephrectomy was attempted in 15 patients and completed successfully in 14. Conversion to flank incision was resorted to one patient because of a venous bleeding. Median operating time was 290 min (SD: 57). Mean warm ischaemia time was 7 min (range: 4-17), including laparoscopic harvest. All kidneys were functioning well after transplantation. The mean duration of postoperative hospitalization of the donors was 4 days. CONCLUSION: Laparoscopic live donor nephrectomy is a safe and technically feasible procedure in a kidney transplant programme involving a living relative.

Adult↗
PubMed1999

Renal graft survival in native and non-native European recipients.

Most studies on the influence of recipient race on kidney transplant survival have been performed in the United States. Generally, they show a lower survival in African-Americans than in Caucasians. Since Rotterdam has gradually become a multi-ethnic society, we were able to study the effect of origin on kidney survival. We restricted our study to recipients of a primary cadaveric kidney graft between July 1983 and July 1997 who received cyclosporin as primary immunosuppression. Patients were divided into two main groups according to origin: European (n = 399) and non-European (n = 110). No statistical differences were found for mean donor age, sex distribution, or the total number of HLA-A and DR mismatches. Non-Europeans had significantly more mismatches on their HLA-B locus (P = 0.01) and recipient age was lower (P = 0.003). The reason non-Europeans had lost their native kidneys was more often hypertension and less often congenital or hereditary diseases compared to Europeans. The causes of death and of transplant failure did not differ. A multivariate Cox proportional hazards analysis did not show European or non-European origin to be an independent predictor of graft survival (two categories, P = 0.25). The variable origin in five categories did show an independent influence on graft survival, with Arab en African recipients running higher risks than European and Asian recipients. We conclude that, in our center, the prognosis after kidney transplantation is comparable for Europeans and non-Europeans; however, in the subcategories, Arab and African recipients have a worse prognosis.

Adult↗
PubMed1999

Interstitial laser coagulation for hepatic tumours.

BACKGROUND: The potential role of interstitial laser coagulation (ILC) for patients with irresectable hepatic tumours is currently being investigated. Since its introduction in 1983 it has evolved into an innovative minimally invasive technique. METHODS: On the basis of a Medline literature search and the authors' experience, the principles, current state and prospects of ILC for hepatic tumours are reviewed. RESULTS: Animal studies and early clinical studies have shown the safety and feasibility of ILC. The site of interest can be approached at laparoscopy or percutaneously and treatment is easily repeatable. Recent advances include the use of fibres with a cylindrical diffusing light-emitting tip, the length of which is adaptable to tumour diameter, water-cooled fibre systems, simultaneous multiple fibre application, and hepatic inflow occlusion during laser treatment. ILC allows complete destruction of tumours up to 5 cm in diameter. Currently a limitation is the lack of reliable real-time monitoring of laser-induced effects but progress in magnetic resonance imaging techniques should allow accurate temperature measurements to be obtained rapidly during treatment. However, the actual benefit of ILC in terms of patient survival remains to be investigated. CONCLUSION: In terms of tools and experience, ILC has now been developed sufficiently to study its effect on survival of patients with irresectable hepatic tumours.

Humans↗