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Query: UMLS:C0020500 (hyperoxaluria)
 912 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Type I primary hyperoxaluria is an uncommon disease related to alanine glyoxylate aminotransferase (AGT) deficiency, an exclusively hepatic enzyme. AGT deficiency leads to an overproduction of oxalate in the liver and consequent hyperoxalemia and massive hyperoxaluria with renal failure. The diagnosis is confirmed by needle biopsy of the kidney showing the exact nature of the enzyme deficiency. When terminal renal failure has developed there are two therapeutic possibilities: kidney graft or a double liver-kidney graft. Kidney graft alone is often insufficient and carries the risk of recurrent disease in the graft since the liver disorder has not been corrected. Inversely, combined liver-kidney graft can not only replace the destroyed kidneys but also correct the metabolic disorder through the effect of the AGT in the donor liver. Although this approach may be successful, it is a very aggressive procedure with high mortality.
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PMID:[Mechanisms and treatment of primary type I hyperoxaluria]. 869 89

Fifty-five Tunisian children with urinary stones, between the ages of 8 months and 15 years, underwent morphological and infrared spectrophotometric analysis of their stones. This study provides an approach to the aetiological profile of urinary stones in Tunisian children. The nucleus of the stones was composed of acidic ammonium urate in 48% of cases with a morphology suggestive of phosphorus deficiency associated with a history of diarrhoea. In 24% of cases, the nucleus contained struvite indicating the presence of urinary tract infection by urease-positive bacteria. The main growth factors of urinary stones were hyperoxaluria and urinary tract infection. In 5 cases, the stones were due to a hereditary lithogenic metabolic disease : cystinuria in 1 case and primary hyperoxaluria in 4 cases.
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PMID:[Etiologic factors of urinary lithiasis in Tunisian children]. 877 1

Primary hyperoxaluria type 1 (PH 1) is complicated by a high rate of early end-stage renal failure (ESRF). In ESRF combined liver kidney transplantation has emerged as treatment of choice for teenagers and adults. In chronic renal failure (CRF) and for small children the situation is less clear. We report on three isolated liver transplantations and show the data of young children from the European Registry for liver transplantation in PH 1. Patient #1 developed ESRF at 3 months of age. Deficiency of alanine:glyoxylate aminotransferase proved PH 1. Progressive bone disease developed and the boy received a living related liver graft (LRLTx) at age two. Due to recurrent cholangitis kidney transplantation (KTx) is currently not feasible. Plasma oxalate decreased after LRLTx indicating correction of the metabolic defect. Patient #2 was diagnosed at the age of 14 months. He had nephrocalcinosis and hyperglycolic hyperoxaluria. Two years later he developed ESRF. At 5 years of age isolated liver transplantation was performed as a first step of therapy. Due to prolonged warm ischemia time organ function was poor. A severe bleeding complicated the course. The child died four weeks after transplantation from untreatable CMV septicemia. Patient #3 was evaluated for failure to thrive at 6 months of age. Urinary oxalate/creatinine ratio was 705 mumol/mol and gave rise to the diagnosis of PH 1. Renal failure slowly progressed to a creatinine clearance of 20 ml/min/1.73 m2 at 8 years, when liver transplantation (LTx) was performed. Four months later, GFR has not changed. Liver function and urinary oxalate/creatinine ratio are normal. Slowly deteriorating chronic renal failure can be stabilized through isolated liver transplantation and thus the rapid need for KTx will at least be delayed. Even more important, normalization of the oxalate metabolism prevents extrarenal oxalate deposits during renal failure.
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PMID:Transplantation procedures in primary hyperoxaluria type 1. 883 45

Considering the clinical heterogeneity of primary hyperoxaluria type I (PH1) and the fact that in many instances this diagnosis was made without enzymatic and immunohistochemical investigation, other disturbances of oxalate metabolism than those presently known can be expected in PH1. Using a gaschromatographic/mass spectrometric method that allows quantification of these acids, hyperoxaluria and hyperglycoluria was found repeatedly in two unrelated patients. The hyperoxaluria was unresponsive to pyridoxine. There was no nephrocalcinosis or urolithiasis. In the liver biopsy normal AGT activity and normal localization of this enzyme in the peroxisome was found. In one patient abnormal Km and maximal activity and mozaicism of AGT were excluded. Hyperoxaluria and hyperglycoluria were also found in other family members, suggesting autosomal dominant transmission. Although the underlying defect leading to hyperoxaluria and hyperglycoluria could not be identified in these patients, it is probable that they represent a separate type of primary hyperoxaluria.
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PMID:Hyperoxaluria with hyperglycoluria not due to alanine:glyoxylate aminotransferase defect: a novel type of primary hyperoxaluria. 891 45

Primary hyperoxaluria (PH) is a severe inherited disease induced by an enzymatic deficiency responsible for high endogenous production of oxalate. Oxalate ions are excreted by the kidney where they can form an insoluble salt with calcium ions, thus inducing urinary stones, crystal deposition in the tubular lumen and renal parenchyma leading to nephrocalcinosis and renal failure. Eighty-seven calculi from 63 PH patients with primary hyperoxaluria were analyzed and compared to 24,130 calculi from unselected consecutive stone formers referred to our laboratory between January 1977 and December 1996. All stones were analyzed according to a protocol including morphological examination of both surface and cross-section, and sequential infrared identification of the crystalline phases. A typical aspect of both surface and section corresponding to morphological type Ic according to our proposed classification (Daudon et al. Scanning Microsc 1993, 7:1081-1106) was observed in all patients but two whereas only two type Ic stones were observed among patients without primary hyperoxaluria. The latter two patients suffered from severe inflammatory bowel disease and developed heavy hyperoxaluria following extensive ileal resection. We conclude that evidence of type Ic morphology is a simple, cheap and fast tool to detect diseases with heavy hyperoxaluria such as primary hyperoxaluria.
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PMID:Unusual morphology of calcium oxalate calculi in primary hyperoxaluria. 960 12

We report a case of a 6-month-old infant who presented with failure to thrive due to end-stage renal disease as a result of primary hyperoxaluria type 1. The infant was managed with a combined daily hemodialysis and peritoneal dialysis prescription in order to manage the total body oxalate burden. Medical management included oral pyridoxine, aggressive hydration and nutritional supplementation via an enteral feeding tube. At one year of age the infant underwent a combined liver/kidney transplantation with intra- and daily post-operative hemodialysis to prevent oxalate deposition in the newly transplanted organs. The post-operative course was complicated by gross hematuria and increased hyperoxaluria, requiring an increase in hydration and thiazide diuretics. This infant received a combination of dialysis modalities which was designed to lower the potential oxalate burden prior to transplantation. This case illustrates the difficulty in medical management of an infant pre- and post-combined liver/kidney transplantation.
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PMID:Diagnosis and management of primary hyperoxaluria type 1 in infancy. 1008 81

In primary hyperoxaluria type 1 (PH 1), deficiency or mistargeting of hepatic alanine glyoxylate aminotransferase (AGT) results in over-production of oxalate and hyperoxaluria, leading to nephrocalcinosis and development of end-stage renal disease (ESRD) in the majority of patients. Renal transplantation (Tx) alone carries a high risk of disease recurrence as the metabolic defect is not cured. Therefore, combined liver/kidney Tx is recommended for patients with ESRD. An alternative approach is to cure PH 1 by pre-emptive isolated liver Tx (PLTx) before ESRD has occurred, but this approach has been carried out only occasionally and there are no uniformly accepted recommendations concerning the timing of this procedure. We report follow-up 3-5.7 yr after performing successful PLTx in four children (at the age of 3-9 yrs) with PH 1 prior to the occurrence of ESRD (glomerular filtration rate [GFR] range 27-98 mL/min/1.73 m2). There was no mortality or long-term morbidity associated with the Tx procedure. Plasma and urinary oxalate levels normalized rapidly within 4 weeks, and renal function did not deteriorate under immunosuppression, even in one patient with advanced chronic renal failure (GFR 27 mL/min/1.73 m2) who showed a stable course for more than 5.7 yrs. Although treatment must be individualized in this severe metabolic disorder, and PLTx has to be regarded as an invasive procedure, we consider that PLTx should be offered and considered early in the course of PH 1. PLTx cures the metabolic defect in PH 1 and can help to prevent, or at least delay, the progression to ESRD and systemic oxalosis.
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PMID:Long-term results of pre-emptive liver transplantation in primary hyperoxaluria type 1. 1093 16

The potential risk of recurrence and degradation of renal function justifies the etiological investigation of all lithiasis-associated pathologies. Therefore calculus analysis of the crystalline phases and morphological characteristics is an important factor in the etiological diagnosis of the disease. Microscopic examination and infrared spectroscopy of calculi from 727 children showed that calcium oxalate was the main component in 36.7% of cases, followed by calcium phosphate (31%), struvite (9.9%) and purine groups (7.7%). The most frequently observed crystalline from was carbapatite (26%), then whewellite (21%) and weddellite (15.7%). As regards the etiopathogenic aspect in adults, the relations between hypercalciuria and weddellite, and between hyperoxaluria and whewellite are also found in the child: in subjects with hypercalciuria, 82% of the calculi contained over 20% weddellite; and in subjects with hyperoxaluria, whewellite was the major constituent in 79% of cases (or 95% in the absence of associated hypercalciuria). In 27 calculi mainly composed of whewellite, the morphological analysis indicated primary hyperoxaluria; this diagnosis was confirmed in 25 cases by specific biological investigation. Urinary tract infection is frequently associated with lithiasis, but its lithogenic role cannot be confirmed without calculus analysis. Several criteria can be used as markers to determine the lithogenic etiology of the infection, i.e., the presence of struvite, the carbonate rate of carbapatite, and the whitlockite and/or protein content of the calculus.
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PMID:[Component analysis of urinary calculi in the etiologic diagnosis of urolithiasis in the child]. 1098 88

Calcium oxalate is a major component of renal stones, and its urinary concentration plays an important role in stone formation. Even a small increase in urinary oxalate has a significant impact on calcium oxalate saturation. Although primary hyperoxaluria is relatively uncommon, patients with calcium oxalate stones have some degree of hyperoxaluria. To understand the underlying causes of such hyperoxaluria, the processes of oxalate synthesis and excretion must be clarified. This article focuses on the determination of oxalate, calculation of its saturation, and the hyperoxaluric syndromes with special reference to metabolic precursors of oxalate, including ascorbic acid, glyoxylate, and glycolate.
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PMID:Oxalate and urinary stones. 1107 50

Combined liver-kidney and kidney-only transplantation outcomes in primary hyperoxaluria (PH) are described. Strategies for the selection of type and timing of transplantation and pretransplantation and posttransplantation management are reviewed. Records were reviewed for 16 patients with PH who received 9 liver-kidney and 10 kidney-only transplants. Plasma oxalate values declined from 61 +/- 42 micromol/L pretransplantation to 9 +/- 6 micromol/L 1 month after transplantation in liver-kidney transplant recipients and 92 +/- 19 to 9 +/- 5 micromol/L in kidney-only transplant recipients. In most liver-kidney transplant recipients, hyperoxaluria persisted for 6 to 18 months after transplantation. Follow-up was 3.5 +/- 4.1 years in liver-kidney and 4.5 +/- 6.3 years in kidney-alone transplant recipients. Patient survival rates were 78% for liver-kidney and 89% for kidney-only transplant recipients. No hepatic allografts were lost. Three of 9 liver-kidney and 6 of 10 kidney-alone transplants lost renal allograft function. In those with functioning kidneys, renal clearance was 45.1 +/- 19.5 mL/min/1.73 m(2) in liver-kidney transplant recipients and 49.5 +/- 26.1 mL/min/1.73 m(2) in kidney-only transplant recipients at last follow-up. Kaplan-Meier 1-, 2-, 3-, and 5-year renal allograft survival rates for patients undergoing transplantation after 1984 were 78%, 78%, 52%, and 52% in liver-kidney transplant recipients and 86%, 71%, 54%, and 36% in kidney-only transplant recipients. Simultaneous grafting of liver and kidney after the development of renal insufficiency is recommended for the majority of patients with PH type I (PH-I). Kidney-alone transplantation is recommended for those with pyridoxine-responsive type I disease because pharmacological therapy allows favorable management of oxalate production in this situation. Kidney-alone transplantation also is recommended for PH type II (PH-II). This disease is less severe than PH-I, and it is currently unknown whether liver transplantation will correct the metabolic defect responsible for PH-II.
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PMID:Combined liver-kidney and kidney-alone transplantation in primary hyperoxaluria. 1169 31


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