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C Noël

Publications and source records attributed to C Noël.

At least 37 records · Page 2Linked to original sources

Renal thrombotic microangiopathy in systemic lupus erythematosus: clinical correlations and long-term renal survival.

BACKGROUND: Renal thrombotic microangiopathy (TMA) is an uncommon vascular complication of systemic lupus erythematosus (SLE). Its clinical symptoms and impact on renal survival remain unclear. METHODS: Eight patients aged 25 +/- 6 years with biopsy-proven renal TMA and at least four ARA criteria for the diagnosis of SLE were retrospectively studied over a 7-year period. RESULTS: All patients presented with renal failure (creatinine 3.3 +/- 2.1 mg/dl), six had proteinuria (2.5 +/- 1.3 g/day) with microscopic haematuria in four cases. Six patients had hypertension, which was severe in five cases. Renal histology disclosed arterial and/or arteriolar thrombosis with parietal thickening without angeitis (8 patients), glomerular microthrombi (3 patients), and vascular fibrin deposits (5/6 patients). In two cases, vascular lesions were associated with a mesangial or a proliferative glomerulonephritis. Thrombocytopenia was present in four patients with haemolytic microangiopathic anaemia in one case. Lupus anticoagulant (LA) was detected in five of eight patients, who also had anticardiolipin antibodies (3/7 patients) and/or were positive for VDRL (3/6 patients). Four patients with LA experienced arterial thrombosis and/or repeated spontaneous abortions. Treatment consisted of corticosteroids (8 patients), cytotoxic drugs (4 patients), plasma exchanges and/or intravenous immunoglobulins (4 patients) and antiplatelet and/or anticoagulant therapy (3 patients). Two patients recovered normal renal function and five had persistent renal insufficiency. One patient started haemodialysis on admission and died of sepsis 2 months later. CONCLUSIONS: TMA may be the sole renal complication in SLE and is not usually associated with haemolytic microangiopathic anaemia. In our series renal survival was influenced by the extent and severity of vascular lesions. Despite a frequent association with antiphospholipid antibodies, pathophysiological mechanisms of renal TMA in SLE remain unknown. Renal histology is mandatory for the diagnosis and the prognostic evaluation of renal vasculopathy in SLE.

Adult↗

Apo(a) phenotypes and lp(a) concentrations in renal transplant patients.

Plasma lipoprotein (a) (LP(a)) concentrations are increased in patients with end-stage renal disease. Considering the influence of the apolipoprotein (a) (Apo(a)) polymorphism and the mode of dialysis in this prospective longitudinal study, we compared Lp(a) concentrations before and after the first 6 months of a successful kidney transplantation in 125 recipient patients. Apo(a) phenotyping was performed by using SDS-PAGE and SDS-agarose, isoforms were classified into high molecular weight (HMW) and low molecular weight (LMW). Before the graft, the Lp(a) concentrations were significantly higher in CAPD than in hemodialysis patients (p = 0.021). Six months after transplantation, Lp(a) fell in both treatment groups. This decrease occurred within both LMW and HMW but to a different extent: median relative variations were -35 and -50%, respectively (p = 0. 048). Among patients with Lp(a) concentration >30 mg/dl 6 months after transplantation, 74% had LMW Apo(a) isoform while the remaining 26% had HMW isoform. Successful renal transplantation leads rapidly to a correction of Lp(a) concentrations, especially in patients treated with CAPD who have higher Lp(a) levels. The most important factor seems to be the LMW status corresponding to high Lp(a) levels.

Adolescent↗

[Limits of parathyroid scintigraphy before surgery for hyperparathyroidism of renal origin].

AIM OF THE STUDY: To evaluate the results of parathyroid scinti scans (sestamibi or tetrofosmin) for detection of hyperplastic parathyroid glands responsible for renal hyperparathyroidism. METHODS: Injection of 15 mCi sestamibi or tetrofosmin and gammacamera acquisition of images focused on neck and mediastinum, 20 minutes and 2 hours thereafter. Injection of 150 mCi Iodine 123, acquisition of images 2 hours afterwards and visual subtraction. PATIENTS: 51 patients with renal insufficency or renal transplant were referred for surgical treatment of hyperparathyroidism. 52 scintiscans (sestamibi n = 19, tetrofosmin n = 33) were performed before operation (subtotal parathyroidectomy, bilateral thymectomy and parathyroid tissue cryopreservation). RESULTS: 180 hyperplastic parathyroid glands were resected, 71 of which had been detected by scintiscan. The factors modifying the results were the weight of the resected lesion and reoperation. All hyperplastic glands were detected in only 1 out of 41 scintiscans performed before first hand operations, whereas all missed glands were imaged in 8 out of the 10 explorations performed before reoperation for persistent renal hyperparathyroidism. The radionuclide, the type of hyperparathyroidism, the parathyroid location, patient's age and gender did not influence the results. No false-positive result was observed. CONCLUSION: Parathyroid scintiscan should not be routinely performed before the first neck exploration for renal hyperparathyroidism. It is mandatory in those cases needing reoperation for recurrent disease.

Adolescent↗

A randomized controlled trial of pentoxifylline for the prevention of delayed graft function in cadaveric kidney graft.

Ischemia/reperfusion has been implicated in the mechanism of delayed graft function (DGF). Pentoxifylline (PTX) has been shown to suppress TNF alpha (released by activated macrophages, inhibiting subsequent superoxide anion release from neutrophil activation. In addition, PTX decreases cyclosporine (CsA) induced renal endothelial release and vasoconstriction. Thus, administration of PTX to renal transplant patient could be an excellent approach to prevent DGF and vascular toxicity of CsA in the early graft period. One hundred-and-forty consecutive patients receiving cadaveric kidney transplantation were registered in a randomized double-blind study comparing PTX vs. a placebo. PTX had no demonstrable effect on the incidence of DGF, on the rapidity of the renal function recovery, and on the ability to use higher doses of CsA in the first month post-graft.

Adult↗

[Burns].

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Burns↗

[Axillo-axillary access in hemodialysis].

Axillo-axillary angio-access can be an alternative device (bovine graft or synthetic graft) for dialysis patients among whom upper arm peripheral veins are impracticable or previous fistulas are thrombose. This procedure was used in seven dialysis patient (length of dialysis: 52.2 +/- 40.6 months) among whom forty one angio access were done. Except one immediate failure, these access were patent until, either the death of patients or the achievement of a cadaveric renal graft. The clinical and hemodynamic tolerance were perfect.

Adult↗

[Incidence and clinical expressions of microvascular complications in patients receiving kidney graft and treated with cyclosporine].

Reported cases of HUS/TTP (hemolytic uremic syndrome/thrombotic thrombopenic purpura) with cyclosporin (CsA) are more and more frequent, which led us to evaluate the incidence of microangiopathic process in kidney graft patients. In our first retrospective study we noted 9.4 percent of HUS/TTP among 117 patients. We tried to detect infraclinical hemolytic events prospectively in 40 new patients by systematic measurement of haptoglobin levels after introduction of CsA. The incidence of falls in haptoglobin levels was 25 percent. The immunological context was always noted: rejection crisis in 5 cases, cytomegalovirus infection in 3 cases, isolated markers of lymphocyte-activity in 2 cases. We never found a clinical or infraclinical form of microangiopathic process without a symptomatic or asymptomatic immunological complication. Monitoring haptoglobin levels make it possible to detect early endothelial injuries which could be linked to the future arteriolopathy described with CsA therapy.

Cyclosporine↗

Incidence and clinical profile of microvascular complications in renal allografted patients treated with cyclosporine.

The incidence of cyclosporine (CsA) vascular toxicity is open to debate. We attempted to evaluate the incidence of hemolytic accidents in our series of patients taking all clinical forms into consideration. From January, 1989, to December, 1990, 117 patients received kidneys from cadaver donors and were treated with CsA. Five patients presented hemolytic uremic syndrome (HUS) accompanied by a rejection crisis; 6 patients presented hemolytic anemia associated in 2 cases with marked thrombocytopenia without any evidence of rejection. Cytomegalovirus (CMV) infection was diagnosed in 2 patients and bacterial infection preceded hemolysis in 2 other cases, suggesting a triggering factor. In addition, when we systematically determined haptoglobin levels after introduction of CsA treatment, we found asymptomatic hemolytic episodes more frequently. Our incidence of hemolytic accidents was approximately 10%. Hemolysis could indicate ischemic vascular damage leading to arteriolar medial hyalinosis preceding fibrosis in CsA nephrotoxicity. Thus, it would be interesting to detect asymptomatic forms of hemolysis by monitoring haptoglobin levels. This approach could lead to a reduction of the CsA dose in patients presenting low haptoglobin levels, even in the absence of evidence of nephrotoxicity.

Adult↗

Steroid glucuronides: human circulatory levels and formation by LNCaP cells.

We studied the relationship between circulating androsterone glucuronide, androstane-3 alpha, 17 beta-diol glucuronide and androstane-3 beta, 17 beta-diol glucuronide concentrations and adrenal as well as testicular C-19 steroids in men. Among the three 5 alpha-reduced steroid glucuronides, androsterone glucuronide is the predominant C-19 steroid glucuronide measured in plasma and its levels are markedly elevated compared to those of the non-conjugated steroid. The marked rise in testosterone during puberty was strongly correlated with the increase in both androsterone glucuronide and androstane-3 alpha, 17 beta-diol glucuronide, thus suggesting that testicular C-19 steroids are the main precursors of the steroid glucuronides. We also found that the presence of testicular androgen in plasma contributes to approx. 70% of plasma androsterone glucuronide and androstane-3 alpha, 17 beta-diol glucuronide. Our data suggest that the adrenal C-19 steroids remaining in circulation after castration in men are converted into potent androgen which are then glucuronidated by UDP-glucuronyltransferase. We also demonstrated that the human prostate cell line LNCaP is capable of converting to a large extent androstenedione into androsterone glucuronide. Our data further confirm that glucuronidation is a major pathway of steroid metabolism in steroid target tissues.

Adolescent↗