Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0035078 (renal failure)
 31,970 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Regular dialysis treatment (RDT) does not obviate hyperoxalemia of chronic renal failure (CRF). However, there is emerging evidence suggesting that current dialysis prescription is not always associated with progressive oxalate accumulation. In view of the controversy still concerning this issue we have investigated on plasma profiles and dialysis kinetics of oxalate in patients on RDT. Oxalate was determined by ion chromatography on serum ultrafiltrates and on the whole dialysate in 23 stable patients on RDT for end-stage renal failure unrelated to primary hyperoxaluria. Nine patients were on traditional hemodialysis (HD) and 14 on soft hemodiafiltration (HDF). Plasma profiles showed that dialysis patients were virtually always hyperoxalemic. Dialysis reduced plasma oxalate by more than 60%. There was a post-dialysis oxalate rebound averaging 9.6% at 30 minutes from the end of dialysis. Oxalate dialyzer clearances were mildly higher on HDF than on HD, and were lower than both urea and creatinine clearances, irrespective of the dialysis technique. Distribution space of oxalate was 21.5 1, that is 37.3% of dry body weight, and was quite similar to estimates obtained in normal subjects and in patients with CRF by alternative isotope dilution methods. Oxalate appearance rate averaged 337 +/- 69 mumol/24 h and was not different from the daily oxalate excretion assessed in 40 healthy subjects. Oxalate appearance was significantly related to urea generation and protein catabolic rates. From our results we conclude that, unless metabolic generation of oxalate is increased, current dialysis programs should prevent progressive oxalate accumulation in the majority of the patients.
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PMID:[Kinetics of oxalate in hemodialysis]. 181 40

Plasma oxalate was measured on two occasions in 18 patients with end-stage renal failure on regular haemodialysis treatment: once while on a routine dose of vitamin C (100 mg/day) and subsequently after 2 weeks administration of a larger dose of vitamin C (500 mg/day). Pre- and post-dialysis concentrations were all markedly increased, reflecting the reduced glomerular filtration rate of end-stage renal failure. Both pre- and post-dialysis oxalate increased significantly following the increase in ascorbate dose but there was no significant correlation between plasma oxalate and ascorbate results. Considerations governing dosage of vitamin C in patients with chronic renal failure are discussed.
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PMID:The effect of vitamin C intake on plasma oxalate in patients on regular haemodialysis. 187 86

The data provided by 14 European centres concerning 22 combined liver-kidney and two isolated liver grafts performed in primary hyperoxaluria type 1 (PH1) were discussed at a workshop which drew the following main conclusions: 1. In end-stage renal failure due to PH1 1-year kidney graft survival rate is far better after combined liver-kidney transplantation than after kidney transplantation alone. This may be due to enhanced renal graft tolerance induced by the simultaneously grafted liver, in addition to the reduced risk of oxalate-induced damage to the kidney graft because the oxalate overproduction has been corrected. 2. Prolonged dialysis using conventional regimes gives rise to extensive systemic oxalosis, especially oxalate osteopathy, which leads to long-lasting excretion of large amounts of oxalate even after oxalate synthesis has been normalised by liver-kidney transplantation, with the risk of jeopardising the success of the kidney graft. In addition, oxalate arteriopathy may endanger the recipient's life. 3. Patients whose GFR is in the range of 25-60 ml/min per 1.73 m2 should be followed up closely, with sequential assessments based on the rate of loss of overall renal function and the plasma and urine oxalate values. An isolated liver transplantation should be considered once the disease has been shown to be following an aggressive course. If this strategy is not followed, planning for an elective liver-kidney graft should begin when GFR decreases to about 25 ml/min per 1.73 m2 and the operation should be as soon as possible. 4. As orthotopic liver transplantation involves the removal of the recipient's biochemically defective but otherwise normal liver, the diagnosis of PH1 should be unequivocally established in every case by the measurement of alanine: glyoxylate aminotransferase enzyme activity in a preoperative liver biopsy.
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PMID:Combined liver-kidney and isolated liver transplantations for primary hyperoxaluria type 1: the European experience. The European Study Group on Transplantation in Hyperoxaluria Type 1. 192 12

This study was carried out in order to investigate renal oxalate excretion in a group of normal subjects (n = 40), a group of patients with uremia (n = 52) and a group with nephrolithiasis (n = 34). We found that the mean concentrations of oxalate in the 24-hour urine specimens of both patient groups were below the normal range. Although the renal creatinine clearance (CCR) was significantly decreased in some stone patients (n = 14), decreased renal oxalate clearance was noted only in those patients with severe renal failure. Thus, plasma oxalate was found to be elevated only in patients with chronic renal failure (mean +/- SD, 49.7 +/- 12.4 mumol/l), while the normal value was 17.0 +/- 6.7 mumol/l. The mean tubular excretion fraction of oxalate was also found to increase markedly in uremia with a mean of 26.3 +/- 17.3% (in normal subjects, 11.7 +/- 7.5%), but their mean daily urinary excretion of oxalate decreased to 63.2 mumol/day (mean value of 232.6 mumol/day in normal subjects). A positive correlation was observed between oxalate and creatinine, and between oxalate and calcium excretion, which was not found in normal subjects or patients with kidney stones. In nephrolithiasic patients, the daily excretion of oxalate, calcium and phosphate had no discernible increment and the mean excretory ratio of oxalate, calcium or phosphate to creatinine was all within normal limits. But when the CCR of stone patients was below 80 ml/min, their daily excretion of oxalate and calcium decreased significantly (p less than 0.01) and the excretory ratio of phosphate to creatinine markedly increased.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Renal excretion of oxalate in patients with chronic renal failure or nephrolithiasis. 198 Dec 25

We report the cases of two patients who developed cranial nerve palsies after drinking ethylene glycol. A 33-year-old man developed multiple cranial nerve deficits nine days after the ingestion of ethylene glycol in a suicide attempt. Clinical findings included profound bilateral cranial nerve VII palsies and severe dysfunction of cranial nerves IX and X. The neuropathy occurred despite treatment with hemodialysis. The dysphagia completely cleared within two weeks, but at six months a severe bilateral cranial nerve VII dysfunction persisted. A 22-year-old man undergoing hemodialysis for ethylene glycol-induced renal failure developed bilateral cranial nerve VII dysfunction 14 days after ingestion. At a three-month follow-up, the patient demonstrated only moderate functional recovery. The etiology of the cranial nerve deficits is unknown but may be related to oxalate crystal deposition of ethylene glycol-induced pyridoxine dysfunction.
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PMID:Multiple cranial nerve deficits after ethylene glycol poisoning. 199 9

The autosomal recessive disease primary hyperoxaluria type 1 (PH1) is caused by a functional deficiency of the liver-specific peroxisomal enzyme alanine:glyoxylate aminotransferase (AGT). An analysis of liver samples from 59 PH1 patients showed considerable heterogeneity at the enzymic level. Approximately two thirds of patients had zero AGT catalytic activity, whereas the remaining one third had activities that ranged from 3% to 48% of the mean normal level. Two thirds of patients with zero AGT activity also had zero immunoreactive AGT protein, while the other one third, together with all the patients with detectable AGT catalytic activity, had levels of immunoreactive AGT protein that varied from normal to only a few percent of normal. All patients with AGT catalytic activity had their enzyme in the wrong intracellular compartment (ie, mitochondria). On the other hand, in all but one of the patients with immunoreactive AGT protein, but zero catalytic activity, the inactive AGT was correctly located within the peroxisomes. This enzymic heterogeneity was matched by considerable heterogeneity at the clinical level (eg, age at onset, rate of progression, age at renal failure, etc). No simple relationship was found between the level of hepatic AGT and the severity of the disease. It is suggested that a lack of AGT might be responsible for a broader pathological phenotype than classically associated with PH1. The possibility is advanced that some patients with idiopathic oxalate stone disease might owe their predisposition to stone formation to a functional deficiency of AGT.
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PMID:Molecular and clinical heterogeneity in primary hyperoxaluria type 1. 200

A 23-year-old man with type 1 primary hyperoxaluria, renal failure, and oxalosis developed a severe cardiomyopathy while awaiting combined liver-kidney transplantation. This manifested as radiographic cardiomegaly, a dilated hypokinetic left ventricle with a decreased ejection fraction, ventricular arrhythmias, and cardiac uptake on bone scanning. On liver and kidney transplantation, these abnormalities markedly improved and/or reversed. The cardiac size almost normalized, the left ventricular ejection fraction increased from 20% to 34%, the ventricular arrhythmias resolved, and the cardiac uptake on bone scanning disappeared. This coincided with normalization of oxalate production and excretion. Severe cardiac involvement secondary to oxalosis in patients with primary hyperoxaluria may improve or reverse with combined liver-kidney transplantation.
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PMID:Reversal of cardiac dysfunction secondary to type 1 primary hyperoxaluria after combined liver-kidney transplantation. 201 90

We describe the clinical, radiographic and histological features of skeletal involvement in four patients with end-stage renal failure due to primary oxalosis. The clinical features were unrelenting bone pain, and in two patients multiple fractures. Radiographic features were, in chronological order: (1) radiodense metaphyses and other red marrow bone; (2) cortical defects in metaphyses; (3) spontaneous fracture-separations of epiphyses of long limb bones which healed poorly. The fractures occurred through crystal deposits, and fracture displacement was associated with extrusion of crystalline material from bone. On histological examination crystals were found to replace metaphyseal bone. Pericrystalline giant cell granulomata replaced bone marrow. Erosion surfaces near granulomas were increased. Subperiosteal and intra-osseous tophi of calcium oxalate were seen. Calcium oxalate appears to precipitate with greater facility than does physiological mineral. Bone showed the features of mixed uraemic osteodystrophy in all four patients. We conclude that: (1) the fractures occurred through heavy crystal deposits; (2) ununited fractures and intra-osseous and subperiosteal tophi contributed to the pain; (3) spontaneous fractures are of poor prognostic significance. We recommend that unstable fractures be internally fixed.
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PMID:Skeletal manifestations of primary oxalosis. 203 34

It can be difficult to distinguish between primary hyperoxaluria at end-stage renal failure and secondary oxalosis, all the more as primary hyperoxaluria can be latent for a long time and occur at a late stage. A 57 year-old woman, without family nor personal history of urolithiasis, receives regular hemodialysis for a renal failure discovered at end-stage. Eighteen months later, calcium oxalate deposits appear in the skin, bone marrow and both kidneys, suggesting secondary oxalosis. An other 57 year-old woman presents a chronic renal failure due to bilateral urolithiasis, whose surgery has caused a dramatic decrease of renal function requiring regular hemodialysis. Because of apparition of severe bone alterations, a parathyroidectomy is realized, and because of calcium oxalate deposition in the skin and bone marrow, primary hyperoxaluria is suspected. In both observations, the enzyme activity determination in a liver biopsy gives the diagnosis of primary hyperoxaluria.
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PMID:[Adult type I primary hyperoxaluria: 2 cases confirmed by liver biopsy at end-stage renal insufficiency]. 207 21

The present study was undertaken to evaluate three factors which may contribute to the myocardial deposition of calcium oxalate in 5/6 nephrectomised rats: (1) increased plasma oxalate, (2) elevated plasma ionised calcium, and (3) local myocardial tissue damage. A simple increase in plasma oxalate concentrations produced by injection of sodium oxalate did not cause deposits in the heart. Increased plasma ionised calcium combined with elevated plasma oxalate for 60 days was likewise unimportant with regard to cardiac deposits. However, when local tissue damage was added by heterotopic cardiac transplantation, deposition of crystals was seen in four or five allografts damaged by rejection. In this model the rat's own heart was not affected. Although an increase in plasma oxalate values is not without significance, the present findings suggest that local tissue damage is a more important factor in the myocardial deposition of oxalate crystals in renal failure.
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PMID:Oxalate crystal deposits in the heart in chronic renal failure: an experimental study. 213 Feb 93


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