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C Noel

Publications and source records attributed to C Noel.

At least 19 recordsLinked to original sources
PubMed2006

[Results of systematic subtotal parathyroidectomy with thymectomy for tertiary hyperparathyroidism after renal transplantation - 70 patients].

BACKGROUND: Due to the relatively small number of patients involved, there is currently no consensus on what operation should be performed in patients with tertiary hyperparathyroidism after renal transplantation. METHOD: Retrospective analysis of the 70 patients with tertiary hyperparathyroidism who all underwent subtotal parathyroidectomy with transcervical thymectomy in the same institution between 1978 and 2003. RESULTS: The delay between transplantation and parathyroidectomy was 4,1+/-4,3 years. Follow up was available for all patients. Mean follow-up was 5,6+/-5 years. Glomerular filtration rate (GFR) was 53+/-21 ml/min at parathyroidectomy and 42+/-29 ml/min at follow-up [<30 ml/min in 26 patients (37%), 30 - 60 ml/min in 25 patients (36%) et>60 ml/min in 19 patients (27%)]. One patient was successfully reoperated for persistent tertiary hyperparathyroidism during follow-up. No patient was hypercalcemic at follow-up. Four patients with a GFR<30 ml/min had a PTH level>fourfold normal values (6%) without signs or symptoms of hyperparathyroidism. One patient was hypocalcemic (1,5%) and two patients were normocalcemic with undetectable or infranormal PTH level (3%) under oral vitamin D and calcium medication. CONCLUSION: This approach permits not only to cure the majority of patients with tertiary hyperparathyroidism but also to avoid recurrence when the renal function declines. When medical management has failed, we recommend systematic subtotal parathyroidectomy with thymectomy for patients with tertiary hyperparathyroidism and this should usually be performed during the second year after transplantation.

Adult↗
PubMed2005

[Are preoperative examinations useful in the management of patients with renal hyperparathyroidism?].

AIM OF THE STUDY: To evaluate the efficiency of preoperative parathyroid ultrasonography and scintigraphy in the management of renal hyperparathyroidism. PATIENTS AND METHODS: The charts of the last consecutive 200 patients who underwent surgery for renal hyperparathyroidism from 1998 to 2003 were retrospectively reviewed to collect data concerning parathyroid gland function, results of preoperative ultrasonography and scintigraphy, as well as modalities and results of surgical exploration. RESULTS: Ultrasonography and scintigraphy sensibilities were 36.4% and 49.3%, respectively. Efficiency of both examinations was improved when they were combined (sensibility of 64.7%) and in those patients managed for recurrent hyperparathyroidism. Were more often detected by preoperative examinations glands with high weight and/or greatest diameter, orthotopic and inferior glands as well as glands exhibiting nodular hyperplasia content upon pathological examination. CONCLUSION: Parathyroid ultrasonography and scintigraphy are of poor interest in the management of renal hyperparathyroidism. In a preoperative setting, they should be performed only in patients with recurrent disease.

Adult↗
PubMed2005

Subtotal parathyroidectomy with thymectomy for autonomous hyperparathyroidism after renal transplantation.

BACKGROUND: There is currently no consensus on the operation that should be performed in patients with tertiary hyperparathyroidism (HPT) after renal transplantation. METHODS: : A retrospective analysis of 70 patients with tertiary HPT who underwent subtotal parathyroidectomy with transcervical thymectomy was performed. RESULTS: Mean (s.d.) follow-up was 5.6(5.0) years. Mean (s.d.) glomerular filtration rate (GFR) at follow-up was 42(29) ml/min and was less than 30 ml/min in 26 patients (37 per cent), 30-60 ml/min in 25 (36 per cent) and more than 60 ml/min in 19 (27 per cent). One patient had persistent disease and was cured after reoperation. No patient was hypercalcaemic. Four patients (6 per cent) with a GFR below 30 ml/min had a parathyroid hormone (PTH) level more than four times the normal value without any signs or symptoms of secondary HPT. One patient (1 per cent) was hypocalcaemic and two (3 per cent) were normocalcaemic, with undetectable or below-normal PTH levels while receiving oral vitamin D and calcium medication. CONCLUSION: Systematic subtotal parathyroidectomy associated with thymectomy is effective in treating most renal transplant recipients with tertiary HPT and also minimizes the recurrence of HPT in patients with declining renal function.

Adult↗
PubMed2004

Eligibility of diabetic patients receiving dialysis for islet after kidney transplantation.

INTRODUCTION: The aim of this study was to assess the selection of candidates among 38 dialyzed diabetic patients referred between January 1, 1998 and December 31 2002 for kidney followed by islet transplantation (IAK). The main criteria of eligibility for possible IAK were as follows: (1) plasma C-peptide negative; (2) need for a kidney graft; (3) kidney plus whole pancreas transplantation not desired by the patient; and (4) acceptable results of postkidney graft preislet transplantation evaluation. RESULTS: Seventeen of 38 patients with positive C-p diabetes received a kidney graft alone. Among the 21 C-p-negative diabetic patients, 3 were not eligible for kidney transplantation mainly for psychological reasons and 4 were eligible for kidney plus pancreas transplantation. The remaining 14 C-p-negative patients underwent kidney transplantation or had previously undergone kidney transplantation. Among them, 1 had moved away, 1 refused IAK, one had slightly positive stimulation tests, 1 was overweight, 1 had breast cancer, and 1 had postkidney graft complications. Among the remaining 8 of 14 C-p-negative, kidney-engrafted patients listed for IAK, 5 have undergone transplantation, 3 with a pre-Edmonton and 2 with the Edmonton protocol. CONCLUSION: In conclusion among this series of 38 diabetic patients undergoing dialysis, more than 90% were kidney-grafted. Approximately 50% were ineligible for pancreas transplantation or IAK because of a positive C-p, and 20% were enlisted for IAK. These results highlight the importance of C-p determinations in diabetic dialysis patients to identify eligible patients for pancreas transplantation or IAK.

Adult↗
PubMed2004

Selection of diabetic patients for islet transplantation. A single-center experience.

OBJECTIVE: Since the Edmonton protocol, islet transplantation (IT) offers the prospect of adequate glycemic control with no major surgical risk. In our single-center experience of IT, we studied the recruitment of eligible diabetic patients. METHODS: Between 1998 and 2002, we screened 79 diabetic patients that were divided into 2 groups according to their renal status: 41 were not receiving dialysis (ND) while 38 were receiving ongoing dialysis (D). RESULTS: In the ND group, 20 patients initiated the contact with our team, 8 patients were recruited during hospitalization for very poor glycemic imbalance, and 13 were referred by their diabetologist. 14/41 (34%) patients were ineligible for IT either because of very good glycemic balance, detectable C-peptide (C-p), kidney or liver problems, or plans for future pregnancy. 16/41 (39%) did not wish to proceed, 7 of whom were more interested by a pump. 11/41 (27%) were eligible, among which 8 are currently being assessed, 1 is on the waiting list and 2 have been transplanted. In the D group, 17/38 (45%) had a detectable C-p and received a kidney graft alone. Among the remaining 21 C-p negative diabetic patients, 3 were not eligible for kidney transplantation mainly for psychological reasons, and 4 were enlisted for kidney+pancreas transplantation. The remaining 14 C-p negative patients were kidney-transplanted. Among them, 6 were not eligible for IT, mainly for lack of motivation, slightly positive C-p stimulation tests, obesity, cancer, or increased creatininemia. The remaining 8/14 C-p negative kidney-engrafted patients were enlisted for IT. 3 had secondary failure with the pre-Edmonton immunosuppressive (IS) protocol. Five have been transplanted with the Edmonton-like IS regimen. CONCLUSION: Twenty-five per cent of the 79 patients for whom islet transplantation was considered underwent pregraft assessment and 12% (10 patients, 8 kidney-transplanted and 2 islet alone) of the 79 have been transplanted. The main eligibility criteria were undetectable Cpeptide, normal kidney function, average weight, glycemic imbalance, hypoglycemia unawareness, and glycemic brittleness.

Adult↗
PubMed2003

Kinetics of diabetes-associated autoantibodies after sequential intraportal islet allograft associated with kidney transplantation in type 1 diabetes.

OBJECTIVE: Presence or occurrence of pancreas auto-antibodies (aAb) has been shown to be of poor prognosis for islet cell transplantation. The aim of the study was to monitor the kinetics of these aAb after sequential intra-portal islet plus kidney transplantation with pre-Edmonton immunosuppressive regimen in order to determine whether the sequential protocol of transplantation was involved in the occurrence of the immune response. PATIENTS AND METHODS: Three patients with IDDM and a previous (IAK) or simultaneous (SIK) kidney transplantation received 3 or 4 ABO compatible islet preparations. Islets (> 8 000 IEQ/kg post culture) were sequentially transplanted within a 12 day period via a per-cutaneous catheter. Immunosuppressive treatment included cyclosporine, steroïds and mycophenolate. Plasma ICAs, GAD 65, IA2 and C peptide (C-p) levels were monitored. Type II HLA phenotype was determined in donors and recipients. RESULTS: Patient #1 had high anti-GAD levels (26.5 UI/l) before the IAK, while anti-IA2 and ICA levels were low. After the transplantation, C-p levels increased to 4.9 ng/ml at one month before becoming undetectable at 2 months. GAD levels remained high, ICA and IA2 aAb were undetectable. Patients #2 and #3 did not have significant levels of aAb before the islet transplantation. A slight increase in GAD was observed with each islet transplantation, followed by an overt but transient increase in ICA. IA2 levels remained undetectable. Three months after the transplantation and 2 weeks after the increase of ICA, C-p levels, that were >3.4 ng/ml at one month, fell below 0.2 (N: 0.5-2). CONCLUSION: The immunosuppressive regimen used in kidney transplantation is unable to control perfectly anti-pancreas aAb production. Moreover, these results seem to indicate that the benefits of sequential islet transplantation lie more in the increased islet mass they provide than in potential immune benefit.

Adrenal Cortex Hormones↗
PubMed2002

[Evaluation of verification of brain death and coordination with hospital organ procurement at the University Hospital at Lille].

OBJECTIVES: To determine the incidence of brain death (BD) and to evaluate the registration of potential organ donors (PD) by the organ procurement team (OPT). STUDY DESIGN: Two-year prospective audit in the French university hospital of Lille. PATIENTS AND METHODS: All deaths occurring in the intensive care units or the emergency department were studied. If death was consecutive to brain damage, on-site review of medical records and charts was performed. Death cause, presence of criteria for brain death and reference to the OPT were recorded for each death. A medical expert staff evaluated the incidence of and reasons for unsuitability for organ donation. After 12 months of observation, a protocol for "systematic alert of the OPT when brain death is suspected" was broadcast and evaluated during the next 12 months. RESULTS: During the first period, 277 BD occurred and 119 PD were suitable for organ donation. The OPT recorded 80 PD (67.2% of all PD) and 45 multi-organ procurements (MOP) were performed. Physicians opposed two major reasons for not calling OPT: anticipation of a non-validated medical contraindication in 18 cases and approach of the family without the OPT team in 21 cases. After broadcast of the protocol, 110 PD were identified and the OPT was called in 93 cases (84.5% of all PD, p < 0.004 versus first period). Fifty-three MOP were performed. CONCLUSION: The OPT was not called to manage one-third of the PD. The protocol for "systematic alert of the OPT when brain death is suspected" improves the call of the OPT and increases MOP.

Brain Death↗
PubMed2000

Negative immunohistochemical detection of CD103 (alphaEbeta7 integrin) in the infiltrates of acute rejection in liver and kidney transplantation.

BACKGROUND: The infiltration of epithelium by CD8+ T lymphocytes in human renal or liver allografts is a critical feature of acute rejection. CD103 expression can be acquired in vitro by CD8+ cytotoxic T lymphocytes in response to allogeneic renal epithelial cells and promotes their adhesion to epithelium and subsequent lysis of epithelial cells. We investigated the expression of CD103 in T-cell infiltrates during acute renal or liver rejection (grade < III). METHODS: Immunohistochemical detection of CD103 in 11 liver and 10 kidney transplant biopsies with histopathological diagnosis of acute rejection. RESULTS: None of the infiltrates expressed detectable CD103, although positive controls were stained under our conditions. CONCLUSIONS: Failure to detect CD103 in renal biopsies can be related to the early posttransplantation interval (<6 months) corresponding to a first rejection episode. In our hands, immunohistological detection of CD103 was not possible in the infiltrates of acute rejection in liver or kidney transplantation.

Acute Disease↗
PubMed2000

Immunomodulatory effect of pentoxifylline during human allograft rejection: involvement of tumor necrosis factor-alpha and adhesion molecules.

BACKGROUND: Pentoxifylline (PTX), a methylxanthine phosphodiesterase inhibitor, is poorly active as an immunosuppressant but prevents the synthesis of proinflammatory cytokines. In a randomized double-blind study comparing PTX versus placebo in 140 patients receiving cadaveric kidney grafts under cyclosporine and prednisone, we have shown that PTX weakened the consequences of rejection on graft survival. To assess the mechanism underlying the beneficial effect recorded during this trial, we analyzed the impact of PTX on tumor necrosis factor (TNF-alpha) production and expression of cell adhesion molecules. METHODS: Plasma levels of TNF-alpha and its soluble receptors (sTNF-RI, sTNF-RII) and of soluble vascular cell adhesion molecule 1 (sVCAM-1) were monitored over the 6 months postgraft period when PTX or placebo were administered. Expression of VCAM-1 and intercellular cell adhesion molecule 1 was scored by immunohistochemical staining of biopsy specimens from patients who underwent rejection crisis. Lymphocyte subset composition was analyzed longitudinally during cytomegalovirus (CMV) infections. RESULTS: Plasma TNF-alpha levels were significantly reduced in the PTX-treated group over the 6 months of administration, and specifically during isolated rejection episodes and during CMV infections. Plasma levels of sTNFR-I, sTNFR-II, and sVCAM-1 did not differ between the two groups of patients, but a decrease in renal tubular VCAM-1 expression was observed in the PTX group. During CMV infections, CD8 lymphocytosis and expansion of CD57+ (CD28-) CD8+ T cells were similar in the two groups. CONCLUSION: The data collected during this double-blind study point to an immunomodulatory role of PTX, the beneficial effect on graft survival resulting from a restraining effect of the drug on the inflammatory conditions involved in acute graft rejection.

Adjuvants, Immunologic↗
PubMed2000

Intraoperative decay profile of intact (1-84) parathyroid hormone in surgery for renal hyperparathyroidism--a consecutive series of 80 patients.

BACKGROUND: The utility of intraoperative parathyroid hormone (PTH) monitoring is unclear in the surgical management of renal hyperparathyroidism. Our goal was to define the normal pattern of decay during operation for renal hyperparathyroidism by using the rapid intact (1-84) parathyroid hormone (PTH) assay. METHODS: Eighty consecutive patients underwent neck exploration for renal hyperparathyroidism. Intact PTH levels were monitored with a rapid immunochemiluminometric assay. Samples were assayed at the induction of anesthesia, after dissection before resection, and 20 and 40 minutes after resection. Follow-up ranged from 3 to 24 months. RESULTS: Twenty minutes after resection, PTH levels remained many-fold supranormal. Seventy-seven patients (96%) were cured. Of these, 75 patients (94%) had PTH decay of more than 50% from the preoperative level; 74 (99%) were cured. Only 1 of 3 patients (33%) in whom the PTH level decreased less than 40% from the preoperative level was cured. Two patients had intermediate values and both were cured. CONCLUSIONS: The intraoperative decay of PTH during operation for renal hyperparathyroidism is slower than for patients with normal renal function. However, 20 minutes after resection, a decline to less than 50% of the preoperative level predicts cure, while a level greater than 60% predicts failure.

Adolescent↗
PubMed1998

Improvement in the outcome of rejection with pentoxifylline in renal transplantation: a randomized controlled trial.

BACKGROUND: Pentoxifylline (PTX), a methylxantine phosphodiesterase inhibitor commonly used to treat peripheral vascular disease, has been shown to decrease the production of proinflammatory cytokines and reactive oxygen species and to reduce the toxic effects of cyclosporine. Thus, administration of PTX to transplant patients, as an adjunct to immunosuppressive therapy, could prevent numerous posttransplantation complications. METHODS: One hundred forty consecutive patients receiving cadaveric kidney grafts were registered in a randomized double-blind study comparing PTX at a dose of 800 mg/day, then 1200 mg/day, versus placebo during the first 6 months after transplantation. All patients were followed up for 1 year. RESULTS: Rejection episodes were validated as the only independent risk factor for graft loss in this study. We compared graft survival rates in each group according to the presence or absence of acute rejection. Acute rejection reduced graft survival in the control group (graft survival rate at 1 year, 59% vs. 97%, P < 0.001), but this adverse effect was blunted in the PTX group (72% vs. 89%, NS). This improvement was confirmed by multivariate analysis for risk factors, with graft survival rates being described at best as the interaction between rejection and treatment (PTX vs. placebo, P = 0.045). CONCLUSION: Although PTX does not modify the incidence of any posttransplant complications, it weakens the consequences of rejection on graft survival.

Adult↗
PubMed1998

Genotypic and phenotypic analysis of the polymorphic thiopurine S-methyltransferase gene (TPMT) in a European population.

1. Characterization of allelic variants of the TPMT gene (TPMT) responsible for changes in TPMT activity, and elucidation of the mechanism by which these alleles act, are required because of the clinical importance of this polymorphism for patients receiving thiopurine drugs. 2. We defined the mutational and allelic spectrum of TPMT in a group of 191 Europeans. Using PCR-SSCP, we screened for mutation the entire coding sequence, the exon-intron boundaries, the promoter region and the 3'-flanking region of the gene. Six mutations were detected throughout the ten exons and seven TPMT alleles were characterized. Four of them, TPMT*2, *3A, *3C and *7, harbouring the known mutations, G238C, G460A, A719G or T681G, were nonfunctional and accounted for 0.5, 5.7, 0.8 and 0.3% of the allele totality, respectively. 3. Within the promoter region, six alleles corresponding to a variable number of tandem repeats (VNTR), were identified. VNTR*V4 and *V5a which harbour four or five repeats of a 17-18 bp unit, were the most frequent (55% and 34%, respectively). The other VNTR alleles, having from five to eight repeats, were rarer. 4. The TPMT phenotype was correctly predicted by genotyping for 87% of individuals. A clear negative correlation between the total number of repeats from both alleles and the TPMT activity level was observed, indicating that VNTRs contribute to interindividual variations of TPMT activity. Therefore, additional analysis of the promoter region of TPMT can improve the phenotype prediction rate by genotyping.

Alleles↗
PubMed1997

Recall response to cytomegalovirus in allograft recipients: mobilization of CD57+, CD28+ cells before expansion of CD57+, CD28- cells within the CD8+ T lymphocyte compartment.

BACKGROUND: Strong correlations have been described between persistently elevated proportions of CD57+ (CD28-) CD8+high T lymphocytes and cytomegalovirus (CMV) infection, in healthy individuals as well as in transplant patients. We investigated whether secondary exposure to CMV triggers recall responses within the CD8 T cell compartment. METHODS: In a longitudinal study in 123 kidney recipients, we compared 17 primary CMV infections with 27 secondary CMV infections. Subset composition of the CD8 compartment was analyzed by flow cytometry. RESULTS: CD8 lymphocytosis occurred significantly earlier (by 17 days on average) in CMV reactivations than in primary infections. Both in primary and secondary infections, CD28+ CD8+high T lymphocytes were mainly recruited at the start. In formerly CMV-seropositive patients, preexisting CD57+ CD8+high T lymphocytes switched at the start from no expression of CD28 to high expression of CD28 and, concomitantly, from CD45RA to high expression of CD45RO. These cells reverted rapidly to a CD28- and CD45RA+ phenotype. Nevertheless, the accumulation of CD57+ (CD28-) CD8+high T cells was delayed similarly in primary and secondary CMV infection, progressing over a period between 2 and 8 weeks after the onset of CD8 lymphocytosis to plateau at 366 CD57+ CD8+high cells/ mm3 on average. CONCLUSIONS: The faster kinetics of CD8 lymphocytosis in secondary CMV infection suggests that a recall response triggers cycling "memory" cells within the CD28+ CD8+high subset, while preexistent CD57+ CD8+high T cells with a long-lived cell phenotype can also be mobilized, possibly through the transient acquisition of CD28 expression. The protracted accumulation of CD57+ (and CD28-) lymphocytes might then reflect an end-stage differentiation.

CD28 Antigens↗
PubMed1997

Consecutive successful pregnancies in a combined liver and kidney transplant recipient with type 1 primary hyperoxaluria.

Pregnancy is now a common, but high-risk event, in young women who have received transplants. Consequences to the fetus are known, but pregnancy may also interfere with graft function. We report the outcome of two successive and successful pregnancies in a 29-year-old woman with type 1 hyperoxaluria, who received a combined liver and kidney transplant. Two healthy children were born at 35 and 37 weeks of gestation, with low birth weight. Liver function remained normal before, during, and after pregnancies up to 52 months after transplantation. Renal function was impaired before the first conception, worsened during both pregnancies, and returned to the previous level in both immediate postpartum periods. However, renal function has declined 17 months after the last delivery. This report shows the feasibility of successive pregnancies in multiple organ transplant recipients, but raises the question of long-term maternal kidney graft survival.

Adult↗
PubMed1996

[Pregnancy after hepatic transplantation: what is the maternal risk?].

OBJECTIVES AND METHODS: We report 7 pregnancies which occurred from 1988 to 1995 in 5 women who underwent liver transplantation. The immunosuppression regimen associated cyclosporine, azathioprine and prednisone. RESULTS: Mean age at conception was 25. During pregnancy, cholestasis occurred in 2 women. None of the patients experienced rejection. An increase in serum creatinine was observed in 3 cases. Serum uric acid increased in the third trimester of pregnancy in 6 cases, associated with arterial hypertension in 3 cases. In 4 cases, toxemia led to premature delivery. Seven childbirths occurred between the 34th and 38th week of gestation, by vaginal delivery (n = 3) or caesarean section (n = 4). Newborn weights ranged from 1,350 g to 3,100 g. A favorable outcome was observed in all mothers, with a follow-up ranging from 2 months to 7 years after delivery. CONCLUSION: These results suggest that a successful pregnancy is possible after liver transplantation in young women with normal hepatic function and treated with cyclosporine. The risk of toxemia is mainly related to renal function before pregnancy.

Adult↗