Biomedical subjects

Gisela Offner

Publications and source records attributed to Gisela Offner.

25 records · Page 2Linked to original sources

PubMed2003

Cytokine single nucleotide polymorphisms and intrarenal gene expression in chronic allograft nephropathy in children.

BACKGROUND: Single nucleotide polymorphisms (SNPs) have been reported to influence cytokine production. Certain cytokine high producer genotypes have been associated with an increased risk for acute rejection and chronic allograft dysfunction (CAD) after transplantation. Our study evaluates SNP distribution for transforming growth factor-beta1 (TGF-beta1), interleukin-10 (IL-10), and tumor necrosis factor-alpha (TNF-alpha) in pediatric renal transplant recipients and control individuals and correlates them to corresponding intrarenal gene expression. METHODS: SNPs for TGF-beta1 (codon 10 and 25), IL-10 (positions -1082, -819, -592) and TNF-alpha (position -308) were determined in 30 patients with stable graft function, in 75 patients with CAD, and in 173 control individuals by allele-specific polymerase chain reaction (PCR). Intrarenal cytokine gene expression was studied in 25 biopsies with chronic allograft nephropathy (CAN) and 27 normal kidney specimens by real-time reverse transcription (RT)-PCR. RESULTS: No difference in allele and genotype frequency was detected in any of the investigated groups. No correlation between genotype and intragraft cytokine gene expression was recognized in CAN patients. However, in normal kidney specimens, the low producer TGF-beta1 genotype at codon 10 was associated with significant lower TGF-beta1 mRNA expression. This association was not found for IL-10 or TNF-alpha. CONCLUSION: Our results do not support the proposition that certain specific cytokine genotypes for TGF-beta1, IL-10, and TNF-alpha are associated with CAD. Intrarenal cytokine gene expression only correlated to one TGF-beta1 SNP in normal kidney specimens. Since overall TGF-beta1 expression was higher in transplanted patients compared to controls, this suggests that SNPs may not play a significant role once the immune system is activated.

Adolescent↗

PubMed2003

Kidney transplantation in children: impact of young recipient age on graft survival.

BACKGROUND: It has been suggested that recipient age may have an effect on renal graft survival due to its potential influence on the competence of the immune system. A comparison of graft survival between children and elderly adults, however, has never been performed. METHODS: Forty patients </=18 years old were included in the study group and compared with a control group of patients >/=65 years using a case-control analysis. Apart from age, matching criteria were the number of HLA mismatches and the date of transplantation. RESULTS: The mean age differed by 57 years between study and control group (10 +/- 5 vs 67 +/- 2, P < 0.001). There was no difference in the number of initially non-functioning grafts, sex distribution, immunosuppression, number of HLA mismatches on the HLA-DR, -B and -A locus, cold ischaemia time and the number of patients with panel-reactive antibodies. The only difference was a lower donor age in the study group (17 +/- 14 vs 35 +/- 16, P < 0.001) compared with the control group. During the follow-up of 109 +/- 54 and 79 +/- 49 months, respectively, acute rejections were more frequent in the study group (25 vs 12, P < 0.01). There was no significant difference in graft survival between both groups when death with functioning graft was excluded. CONCLUSIONS: This study which compares two groups of patients with a mean age difference of 57 years could not demonstrate an effect of young recipient age on graft survival, though the incidence of acute rejections appeared to be significantly higher in the paediatric population. Thus paediatric renal transplanted patients do not seem to have a disadvantage regarding graft survival due to their young recipient age.

Adolescent↗

PubMed2002

A multicenter, open-label, pharmacokinetic/pharmacodynamic safety, and tolerability study of basiliximab (Simulect) in pediatric de novo renal transplant recipients.

BACKGROUND: Basiliximab (Simulect) has been shown to be safe and effective in adult renal transplant recipients, when used in combination with cyclosporine (Neoral) and corticosteroids. We report on the safety and preliminary efficacy of basiliximab in pediatric de novo renal transplant recipients. METHODS: This was an open-label, 12-month study of basiliximab in 41 patients (2 cohorts: <9 and 9 to <16 years). In phase 1, two intravenous (IV) bolus injections of basiliximab (12 mg/m ) were administered (before and 4 days postsurgery). In phase 2, two injections (<40 kg, 10 mg and > or =40 kg, 20 mg) were administered at the same time points. Most patients (26/41 [63%]) received cadaveric kidneys. Almost half of the patients had three human leukocyte antigen mismatches with the organ donors. Concurrent immunosuppression included Neoral and corticosteroids. Azathioprine was allowed after 28 days. RESULTS: All patients completed the 1-year study. The acute tolerability of basiliximab via IV bolus injection was good, without evidence of cytokine-release syndrome or acute local reactions. All patients experienced adverse events, but most (71%) were mild or asymptomatic. No deaths or malignancies occurred. The incidence and types of serious adverse events (59%) and serious infections (44%) were as expected in this patient population, and few were drug-related (7% and 5%, respectively). Thirty-eight patients (93%) had infections, mostly urinary tract infections, as expected for renal transplant patients. Six patients (15%) had drug-related adverse events. Biopsy-confirmed acute rejection episodes occurred in 6/41 (15%) of patients during the first 6 months posttransplantation and in 9/41 (22%) patients during the first 12 months. Five patients (12%) experienced graft loss, none of which were preceded by acute rejection episodes. CONCLUSIONS: Basiliximab is safe and well tolerated when administered by IV bolus injection in de novo pediatric renal transplant recipients. These preliminary data suggest that basiliximab, given in combination with cyclosporine and corticosteroids, is an effective immunosuppressive regimen for the prevention of acute rejection in pediatric renal transplantation.

Adolescent↗

PubMed2002

A rational dosing algorithm for basiliximab (Simulect) in pediatric renal transplantation based on pharmacokinetic-dynamic evaluations.

BACKGROUND: The pharmacokinetics and immunodynamics of basiliximab were assessed in 39 pediatric de novo kidney allograft recipients to rationally chose a dose regimen for this age group. METHODS: In study part 1, patients were given 12 mg/m(2) of basiliximab by bolus intravenous injection before surgery and on day 4. An interim pharmacokinetic evaluation supported a fixed-dose approach for study part 2 in which infants and children received two 10-mg doses and adolescents received two 20-mg doses. Blood samples were collected over a 12-week period for analysis of basiliximab and soluble interleukin-2 receptor concentrations, flow cytometry, and screening for anti-idiotype antibodies. RESULTS: Basiliximab clearance in infants and children (n=25) was reduced by approximately half compared with adults from a previous study and was independent of age (1-11 years), weight (9-37 kg), and body surface area (0.44-1.20 m(2) ). Clearance in adolescents (12-16 years, n=14) approached or reached adult values. CD25-saturating basiliximab concentrations were maintained for 31+/-12 days in study part 1 with mg/m(2) dosing and for 36+/-14 days in study part 2 based on the fixed-dose regimen ( P=0.31). A single patient experienced a rejection episode during CD25 saturation. The duration of CD25 saturation in patients who experienced a rejection episode after desaturation did not differ from those who remained rejection-free for the full 6-month period: 34+/-6 days (n=6) vs. 35+/-14 days (n=33 patients); P=0.74. Anti-idiotype antibodies were detected in two patients; however, this did not influence the clearance of basiliximab or the duration of CD25 saturation. CONCLUSIONS: To achieve similar basiliximab exposure as is efficacious in adults, pediatric patients <35 kg should receive two 10-mg doses and those > or =35 kg should receive two 20-mg doses of basiliximab by intravenous infusion or bolus injection. The first dose is given before surgery and the second on day 4 after transplantation.

Algorithms↗

PubMed2002

Kidney transplant in children weighing less than 15 kg: donor selection and technical considerations.

BACKGROUND: Small children represent a challenging patient group in kidney transplantation (KTx). The aim of this study was to analyze patient and donor data influencing outcome in children that weighed <15 kg. METHODS: Sixty-eight kidneys were transplanted in 64 children that weighed <15 kg. In 44 cases, kidneys came from cadaveric donors (CAD) and in 24 cases from living-related donors (LRD). Grafts were placed transperitoneally via midline incision (n=16) or extraperitoneally to the iliac fossa (n=52). Vascular anastomoses were routinely performed to the aorta and vena cava even when the extraperitoneal approach was used. RESULTS: Vascular thrombosis was observed in two (3%), urinary leaks in five (7%), and stenosis in four (6%) patients. In six children receiving organs from adults to the iliac fossa, wound closure was performed using an absorbable mesh to avoid organ compression. Initial graft function occurred in 60 cases (88%). Frequency of initial graft function was significantly higher after KTx from LRD (100%) compared with CAD (82%). The 1-, 5-, and 10-year patient survival was 93%, 91%, and 91%, respectively, and the 1-, 5-, and 10-year graft survival was 92%, 85%, and 85%, respectively. There was no significant difference in patient and graft survival when KTx from LRD and CAD were compared. Within the CAD group, graft survival was improved using kidneys from donors >12 years compared with younger donors. CONCLUSION: Despite size discrepancy between recipients and grafts, KTx is feasible in children that weigh <15 kg by using an improved surgical technique even when adult organs are placed to the iliac fossa.

Body Weight↗

PubMed2002

Drug-induced lupus as a cause of relapsing inflammatory disease after renal transplantation.

We discuss the case of an 18-year-old-boy presenting with relapsing fever, arthralgia, myalgia and renal failure, 7 yr after renal transplantation. A thorough diagnostic work-up for infectious and inflammatory diseases revealed a mastoiditis and atypical mycobacteria, but symptoms persisted after treatment. Persistent antinuclear antibodies in combination with cardiolipin and myeloperoxidase antibodies, despite negative dsDNA antibodies, suggested a drug induced lupus-like syndrome. Six months after withdrawal of dihydralazine, all symptoms had disappeared. Drug-induced lupus should be considered as an important differential diagnosis in transplanted patients with recurrent inflammatory disease in conjunction with lupus-like symptoms and negative dsDNA antibodies. It may prevent a potentially hazardous reduction of immunosuppression in persistent inflammation.

Adolescent↗

PubMed2002

Single centre experience with basiliximab in paediatric renal transplantation.

BACKGROUND: Introduction of IL-2-receptor antagonists has led to significantly decreasing numbers of acute rejection episodes in renal transplantation in adults. No data are available in paediatric recipients. METHODS: Between 1997 and 2000, 78 renal transplantations were performed in 77 children aged 0.5-16 years. Basiliximab, cyclosporin A (CsA) and prednisolone were administered in 48 children (age 7.8 +/- 5.3 years) and compared with 29 children (age 7.3 +/- 5.2 years) receiving CsA and prednisolone only. The number of acute rejections, survival, glomerular filtration rate (GFR) and side effects were determined for 3 years after transplantation. RESULTS: All 77 patients survived the observation period. One year graft survival in the basiliximab group was 95%, which is similar to the comparison group (93%). Children receiving basiliximab showed a lower incidence of acute rejection than the comparison group (14% vs 34%). The calculated GFR was lower in the basiliximab group when discharging from hospital, with 51 compared with 66 ml/min/1.73 m(2) in the non-basiliximab group. This was associated with higher CsA trough levels (214 vs 174 ng/ml) in the basiliximab patients. After 1 year the GFR was comparable in both groups (58 vs 52 ml/min/1.73 m(2)). CONCLUSIONS: Basiliximab offers excellent allograft survival, a lower incidence of acute rejections and almost no side effects. Therefore it can be recommended for routine immunosuppressive therapy in paediatric renal transplantation.

Adolescent↗