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Nassim Kamar - One of the best experts on this subject based on the ideXlab platform.
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recurrence of oxalate nephropathy after Isolated Kidney transplantation for primary hyperoxaluria type 2
American Journal of Transplantation, 2018Co-Authors: Arnaud Del Bello, Olivier Cointault, Audrey Delas, Nassim KamarAbstract:We read with interest the case report by Dhondup et al., who suggest that combined liver–Kidney transplantation should be considered for patients with end-stage chronic Kidney disease (CKD) caused by primary hyperoxaluria type 2 (PH2). This is in contrast to Isolated Kidney transplantation that is usually proposed (1). This article is protected by copyright. All rights reserved.
Pierre Cochat - One of the best experts on this subject based on the ideXlab platform.
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combined liver Kidney transplantation in primary hyperoxaluria type 1
Transplantation, 1999Co-Authors: Pierre Cochat, Jeanmichel Gaulier, P Koch C Nogueira, Janusz Feber, N V Jamieson, Marieodile Rolland, P Divry, Dominique Bozon, Laurence DubourgAbstract:Primary hyperoxaluria type 1 (PH1) is a rare autosomal recessive disorder characterised by an increased urinary excretion of calcium oxalate, leading to recurrent urolithiasis, nephrocalcinosis and accumulation of insoluble oxalate throughout the body (oxalosis) when the glomerular filtration rate falls to below 40–20 mL/min per 1.73 m2. The disease is due to a functional defect of the liver-specific peroxisomal enzyme alanine: glyoxylate aminotransferase (AGT), the gene of which is located on chromosome 2q37.3. The diagnosis is based on increased urinary oxalate and glycollate, increased plasma oxalate and AGT measurement in a liver biopsy. AGT mistargeting may be investigated by immuno-electron microscopy and DNA analysis. End-stage renal failure is reached by the age of 15 years in 50% of PH1 patients and the overall death rate approximates 30%. The conservative treatment includes high fluid intake, pyridoxine and crystallisation inhibitors. Since the Kidney is the main target of the disease, Isolated Kidney transplantation (Tx) has been proposed in association with vigorous peri-operative haemodialysis in an attempt to clear plasma oxalate at the time of Tx. However, because of a 100% recurrence rate, the average 3-year graft survival is 15%–25% in Europe, with a 5–10-year patient survival rate ranging from 10% to 50%. Since the liver is the only organ responsible for the detoxification of glyoxylate by AGT, deficient host liver removal is the first rationale for enzyme replacement therapy. Subsequent orthotopic liver Tx aims to supply the missing enzyme in its normal cellular and subcellular location and thus can be regarded as a form of gene therapy. Because of the usual spectrum of the disease, Isolated liver Tx is limited to selected patients prior to having reached an advanced stage of chronic renal failure. Combined liver-Kidney Tx has therefore become a conventional treatment for most PH1 patients: according to the European experience, patient survival approximates 80% at 5 years and 70% at 10 years. In addition, the renal function of survivors remains stable over time, between 40 and 60 mL/min per 1.73 m2 after 5 to 10 years. In addition, liver Tx may allow the reversal of systemic storage disease (i.e. bone, heart, vessels, nerves) and provide valuable quality of life. Whatever the transplant strategy, the outcome is improved when patients are transplanted early in order to limit systemic oxalosis. According to the European experience, it appears that combined liver-Kidney Tx is performed in PH1 patients with encouraging results, renal Tx alone has little role in the treatment of this disease, and liver Tx reverses the underlying metabolic defect and its clinical consequences.
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epidemiology of primary hyperoxaluria type 1
Nephrology Dialysis Transplantation, 1995Co-Authors: Pierre Cochat, A Deloraine, M Rotily, F Olive, I Liponski, N DeriesAbstract:Primary hyperoxaluria type 1 (PH1) always leads to oxalate accumulation throughout the body (oxalosis). Currently available epidemiological data only concern patients with end-stage Kidney disease requiring renal replacement therapy (RRT). French nephrologists have been questioned about PH1 patients who were under their care between 1988 and 1992. Exhaustive answers were obtained and 90 cases of PH1 were collected. The average prevalence rate of PH1 was 1.05/10(6) and its average incidence rate was 0.12/10(6)/year. The median age at onset was 5 years (0-63) and initial symptoms involved the urinary tract in 82% of the cases. Half the patients were younger than 10 years at the time of diagnosis on the basis of urine oxalate (89%) +/- urine glycolate (43%) +/- plasma oxalate (71%) +/- hepatic alanine:glyoxylate amino-transferase activity (48%). At the time of the survey, 36% of patients were on a conservative treatment, 37% were transplanted and 27% were on maintenance haemodialysis; the crude mortality rate was 19% (median age 36 years). Patients on dialysis started RRT at a median age of 25 years. Transplanted patients received their first transplant at a median age of 29.5 years; among those patients with more than 1 year follow-up, 15 received an Isolated Kidney transplant (one success), one had a Isolated liver transplant (one success) and 10 combined liver-Kidney transplant (eight successes). These data confirm the rarity of PH1 together with its poor prognosis; as shown in the European experience, early combined liver-Kidney transplantation seems to be the best therapeutic proposal.
Bernd Hoppe - One of the best experts on this subject based on the ideXlab platform.
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an update on primary hyperoxaluria
Nature Reviews Nephrology, 2012Co-Authors: Bernd HoppeAbstract:The autosomal recessive inherited primary hyperoxalurias types I, II and III are caused by defects in glyoxylate metabolism that lead to the endogenous overproduction of oxalate. Type III primary hyperoxaluria was first described in 2010 and further types are likely to exist. In all forms, urinary excretion of oxalate is strongly elevated (>1 mmol/1.73 m(2) body surface area per day; normal 30% of patients with primary hyperoxaluria type I. The fact that such a large proportion of patients have such poor outcomes is particularly unfortunate as ESRD can be delayed or even prevented by early intervention. Treatment options for primary hyperoxaluria include alkaline citrate, orthophosphate, or magnesium. In addition, pyridoxine treatment can be used to normalize or reduce oxalate excretion in about 30% of patients with primary hyperoxaluria type I. Time on dialysis should be short to avoid overt systemic oxalosis. Transplantation methods depend on the type of primary hyperoxaluria and on the particular patient, but combined liver and Kidney transplantation is the method of choice in patients with primary hyperoxaluria type I and Isolated Kidney transplantation is the preferred method in those with primary hyperoxaluria type II. To the best of our knowledge, progression to ESRD has not yet been reported in any patient with primary hyperoxaluria type III.
Fatemeh Shaki - One of the best experts on this subject based on the ideXlab platform.
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toxicity of depleted uranium on Isolated rat Kidney mitochondria
Biochimica et Biophysica Acta, 2012Co-Authors: Mirjamal Hosseini, Fatemeh Shaki, Mahmoud Ghazikhansari, Jalal PourahmadAbstract:Abstract Background Kidney is known as the most sensitive target organ for depleted uranium (DU) toxicity in comparison to other organs. Although the oxidative stress and mitochondrial damage induced by DU has been well investigated, the precise mechanism of DU-induced nephrotoxicity has not been thoroughly recognized yet. Methods Kidney mitochondria were obtained using differential centrifugation from Wistar rats and mitochondrial toxicity endpoints were then determined in both in vivo and in vitro uranyl acetate (UA) exposure cases. Results Single injection of UA (0, 0.5, 1 and 2 mg/kg, i.p.) caused a significant increase in blood urea nitrogen and creatinine levels. Isolated mitochondria from the UA-treated rat Kidney showed a marked elevation in oxidative stress accompanied by mitochondrial membrane potential (MMP) collapse as compared to control group. Incubation of Isolated Kidney mitochondria with UA (50, 100 and 200 μM) manifested that UA can disrupt the electron transfer chain at complex II and III that leads to induction of reactive oxygen species (ROS) formation, lipid peroxidation, and glutathione oxidation. Disturbances in oxidative phosphorylation were also demonstrated through decreased ATP concentration and ATP/ADP ratio in UA-treated mitochondria. In addition, UA induced a significant damage in mitochondrial outer membrane. Moreover, MMP collapse, mitochondrial swelling and cytochrome c release were observed following the UA treatment in Isolated mitochondria. General significance Both our in vivo and in vitro results showed that UA-induced nephrotoxicity is linked to the impairment of electron transfer chain especially at complex II and III which leads to subsequent oxidative stress.
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toxicity of depleted uranium on Isolated rat Kidney mitochondria
Research in Pharmaceutical Sciences, 2012Co-Authors: Fatemeh Shaki, Jalal Pourahmad, Mirjamal Hosseini, Mahmoud GhazikhansariAbstract:article i nfo Background: Kidney is known as the most sensitive target organ for depleted uranium (DU) toxicity in compar- ison to other organs. Although the oxidative stress and mitochondrial damage induced by DU has been well investigated, the precise mechanism of DU-induced nephrotoxicity has not been thoroughly recognized yet. Methods: Kidney mitochondria were obtained using differential centrifugation from Wistar rats and mitochon- drial toxicity endpoints were then determined in both in vivo and in vitro uranyl acetate (UA) exposure cases. Results: Single injection of UA(0, 0.5,1 and 2 mg/kg,i.p.) causeda significantincreaseinbloodurea nitrogen and creatinine levels. Isolated mitochondria from the UA-treated rat Kidney showed a marked elevation in oxidative stress accompanied by mitochondrial membrane potential (MMP) collapse as compared to control group. Incu- bation of Isolated Kidney mitochondria with UA (50, 100 and 200 μM) manifested that UA can disrupt the elec- tron transfer chain at complex II and III that leads to induction of reactive oxygen species (ROS) formation, lipid peroxidation, and glutathione oxidation. Disturbances in oxidative phosphorylation were also demonstrated through decreased ATP concentration and ATP/ADP ratio in UA-treated mitochondria. In addition, UA induced as ignificant damage in mitochondrial outer membrane. Moreover, MMP collapse, mitochondrial swelling and cytochrome c release were observed following the UA treatment in Isolated mitochondria. General significance: Both our in vivo and in vitro results showed that UA-induced nephrotoxicity is linked to the impairment of electron transfer chain especially at complex II and III which leads to subsequent oxidative stress. © 2012 Elsevier B.V. All rights reserved.
Arnaud Del Bello - One of the best experts on this subject based on the ideXlab platform.
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recurrence of oxalate nephropathy after Isolated Kidney transplantation for primary hyperoxaluria type 2
American Journal of Transplantation, 2018Co-Authors: Arnaud Del Bello, Olivier Cointault, Audrey Delas, Nassim KamarAbstract:We read with interest the case report by Dhondup et al., who suggest that combined liver–Kidney transplantation should be considered for patients with end-stage chronic Kidney disease (CKD) caused by primary hyperoxaluria type 2 (PH2). This is in contrast to Isolated Kidney transplantation that is usually proposed (1). This article is protected by copyright. All rights reserved.
