Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0451641 (urolithiasis)
 3,973 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Glyoxylate is an immediate precursor of oxalate, but in its metabolism the conversion into glycine catalyzed by serine:pyruvate/alanine:glyoxylate aminotransferase (SPT/AGT) appears to be the main route. When SPT/AGT is missing as in the case of primary hyperoxaluria type 1 (PH1) more glyoxylate is used for the oxalate production, resulting in calcium oxalate urolithiasis and finally systemic oxalosis. SPT/AGT is a unique enzyme of species-specific dual organelle localization; it is located largely in mitochondria in carnivores and entirely in peroxisomes in herbivores and man. For herbivores, the peroxisomal localization of SPT/AGT is indispensable to avoid massive production of oxalate, probably because liver peroxisomes are the main site of glyoxylate production from glycolate, and plants contain glycolate much more than animal tissues. Recently, we took charge of laboratory examination for 8 cases of primary hyperoxaluria in Japan, and felt that symptoms of some of the Japanese PH1 patients are apparently milder than those of Western patients. The reason of this is not clear, but from the above mentioned seemingly indispensable association of grass-eating with the peroxisomal localization of SPT/AGT it may be related, at least in part, to the food habit of Japanese, especially that of old generation, that they prefer boiled greens rather than frying or raw vegetables.
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PMID:Primary hyperoxaluria type 1 in Japan. 1133 44

Primary hyperoxaluria type 1 (PH1) is an inherited metabolic disorder characterized by recurrent urolithiasis and nephrocalcinosis frequently leading to progressive renal insufficiency during the second decade of life. Systemic organ involvement as a result of the accumulation of calcium oxalate crystal deposits in vessel walls often is observed. We report a case of a 56-year-old woman with late-onset of PH1 who developed rapidly progressive renal failure and severe systemic oxalosis with skin and eye involvement despite intensified hemodialytic therapy during the waiting period for combined liver and kidney transplantation. This case illustrates the difficulties in treatment of PH1-induced end-stage renal disease. Combined liver and kidney transplantation should be offered to these patients as soon as possible to reverse the underlying metabolic defect and to restore renal function.
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PMID:A case of late-onset primary hyperoxaluria type 1. 1184 Apr 2

Clinical and genetic epidemiology of inherited renal disease in Newfoundland. Newfoundland's geography, settlement, and socioeconomic development have produced a population useful for the study of genetic diseases. This review examines the clinical and genetic epidemiologic studies of inherited renal diseases undertaken in this population in the past 15 years. Common founder effects and large families through each generation provided very extensive pedigrees with autosomal-dominant diseases, such as polycystic kidney disease (PKD) and von Hippel-Lindau disease. In the former disease the diagnostic utility of renal ultrasound was determined, as was the prognostic impact of genotype, the role of the renin-angiotensin system in the pre-hypertensive phase, the potential for somatic mutations of the PKD2 gene, or the combination of mutations in the PKD1 and PKD2 genes, in single cells to induce cysts, and the demonstration that human transheterozygotes of PKD1 and -2 are not embryonically lethal. The presence of multiple genetic isolates and the high coefficient of kinship have predisposed to autosomal recessive diseases such as Bardet-Biedl syndrome (BBS), autosomal-recessive PKD, primary hyperoxaluria, and dihydroxyadenine urolithiasis. We have reported the clinical manifestations and natural history of the BBS, with particular emphasis on the fact that renal abnormalities are cardinal manifestations of the disease, the presence of at least six different genotypes, the identity and function of the BBS6 gene, and the presence of three different BBS6 mutations. Because of its relatively homogenous origins and high coefficient of kinship, Newfoundland's population also may be useful for the study of complex diseases such as preeclampsia. Using unbiased ascertainment and strict diagnostic criteria, we have found a significant risk of preeclampsia and non-proteinuric gestational hypertension in sisters of probands with preeclampsia, particularly when probands are defined by severity of preeclampsia, an observation that supports a study to search for susceptibility genes. We conclude that collaborations between clinical epidemiologists and molecular geneticists, using the Newfoundland population, have provided important clinical and mechanistic insights into inherited renal diseases.
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PMID:Clinical and genetic epidemiology of inherited renal disease in Newfoundland. 1202 33

Primary hyperoxaluria type 1 (PH1) usually presents with recurrent urolithiasis, nephrocalcinosis and progressive renal failure at a relatively young age. This report describes a patient who, due to the late onset of end-stage renal disease, had been diagnosed with PH1 only after failure of his second kidney graft. Retrospectively, his vascular problems, skeletal abnormalities and cardiac arrhythmias fit the picture of severe systemic oxalosis. Possible therapeutic options are discussed.
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PMID:Renal graft failure due to type 1 primary hyperoxaluria. 1260 92

Primary hyperoxaluria (PH) is a heterogeneous disease with a variable age of onset and a variable progression into kidney failure. Early diagnosis is mandatory to avoid the damaging effects of systemic calcium oxalate deposition. In 1997, we initiated a nationwide survey of American nephrologists to ascertain epidemiological data and current practices. PH was reported in only 102 patients, with PH I in 79 and PH II in 9; 14 patients were not classified. Most patients were Caucasian (84%). Main symptoms at diagnosis were urolithiasis (54.4%) and nephrocalcinosis (30%). A significant delay of diagnosis was seen in 42% of patients and 30% of patients were diagnosed only at end-stage renal disease (ESRD). Diagnosis was usually based on history and urinary oxalate excretion. Glycolate and l-glyceric acid excretion were rarely determined. To determine the enzyme defect, a liver biopsy was performed in 40%. Even at ESRD, only 56% of patients received an adequate diagnostic work-up. Half of the patients showed 'good' or 'fair' pyridoxine sensitivity. In addition to B(6), most patients received either citrate or orthophosphate. Kidney transplantation (KTx) failed in 19 of 32 transplants ( n=27 patients) and was due to recurrent oxalosis in 8 transplants. Liver Tx was performed after KTx in 5 patients (1 patient died). Combined liver-kidney Tx in 21 patients (in 9 patients after failure of KTx) achieved good organ function in 13 patients; 7 patients, however, died shortly after transplantation. In conclusion, the time between first symptom and diagnosis of PH must be minimized, and the diagnostic procedures have to be improved. The cases of unclassified hyperoxaluria suggest the possibility of additional type(s) of PH. As isolated KTx failed in 59% of patients, combined liver-kidney Tx seems to be the better choice in place of isolated KTx as the primary transplant procedure.
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PMID:A United States survey on diagnosis, treatment, and outcome of primary hyperoxaluria. 1292 Jun 26

Secondary hyperoxaluria is due either to increased intestinal oxalate absorption or to excessive dietary oxalate intake. Certain intestinal diseases like short bowel syndrome, chronic inflammatory bowel disease or cystic fibrosis and other malabsorption syndromes are known to increase the risk of secondary hyperoxaluria. Although the urinary oxalate excretion is usually lower than in primary hyperoxaluria, it may still lead to significant morbidity by recurrent urolithiasis or progressive nephrocalcinosis. A clear distinction between primary and secondary hyperoxalurias is important. As correct classification may be difficult, appropriate diagnostic tools are needed to delineate the metabolic background as a basis for optimal treatment. We developed an individual approach for the evaluation of patients with suspected secondary hyperoxaluria. First, 24 h urines are examined repeatedly for lithogenic (e.g. calcium, oxalate, uric acid) and stone-inhibitory (e.g. citrate, magnesium) substances, and the patients are asked to fill in a dietary survey form. Urinary saturation is calculated using the computer based program EQUIL2, and the BONN-Risk-index is determined. The measurement of plasma oxalate and of urinary glycolate helps to distinguish between primary and secondary hyperoxalurias. If secondary hyperoxaluria is suspected, the stool is examined for Oxalobacter formigenes, an intestinal oxalate degrading bacterium, as lack or absence may lead to increased intestinal oxalate absorption. The last diagnostic step is to study the intestinal oxalate absorption using [13C2]oxalate. Depending on the results, various therapeutic options are available: 1) a diet low in oxalate, but normal or high in calcium, 2) a high fluid intake (>1.5 L/m2/d), 3) medications to increase the urinary solubility, 4) specific therapeutic measures in patients with malabsorption syndromes, depending on the underlying pathology, and 5) intestinal recolonization of Oxalobacter formigenes or the treatment with other oxalate degrading bacteria.
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PMID:Diagnostic and therapeutic approaches in patients with secondary hyperoxaluria. 1295 11

Primary hyperoxaluria type I is a rare inborn error of metabolism caused by a deficiency of a liver-specific peroxisomal enzyme. It manifests by increased oxalate production that ultimately results in kidney failure, due to urolithiasis and nephrocalcinosis, and finally induces systemic oxalosis and risk of premature death. Primary hyperoxaluria type 2 is mainly responsible of urolithiasis. Enteric hyperoxaluria is a commonly seen adverse event of Crohn disease or after extensive intestinal resection. These affections represent the main etiologies of massive hyperoxaluria. If not recognized very soon and adequately treated, these conditions can progress rapidly to end stage renal failure.
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PMID:[Massive hyperoxaluria]. 1549 71

Regular calculation of urinary crystallization risk indices in patients suffering from urolithiasis is a recommended measure for treatment adjustment. The more the patient experiences either extensive stone formation or an enhanced recurrence rate, the more important risk index calculations. In patients suffering from primary hyperoxaluria type 1 (PH1), both criteria are met. Different methods of risk determination are known. All strategies for measuring the calcium oxalate (CaOx) crystallization risk of a given urine principally determine this parameter from voided urine. This "bladder urine", however, has possibly passed stone material located in the urinary tract and thus may be depleted in lithogenic components. This is commonly the case for patients with PH1, who mostly experience a massive stone burden or severe nephrocalcinosis. Hence, the question arises as to whether we can adequately determine the crystallization risk in the urine of stone-bearing PH1-patients or not. Based on model calculations, we show that the determination of CaOx formation risk in PH1-patients requires knowledge of the restrictions in risk index interpretation: risk indices calculated from urinalysis (e.g. EQUIL) still indicate, even after strong in vivo stone formation, an enhanced but in fact strongly underestimated risk value. However, the outcome "enhanced" masks the patient's true risk situation. The BONN Risk Index (BRI), in contrast, discloses the process of extreme in vivo crystal formation. As determined, inter alia, from the urinary concentration of free ionized calcium ([Ca(2+)]), BRI approaches abnormally low values, as, in consequence of CaOx - formation, [Ca(2+)] tends to values close to zero. Thus, calculations of urinalysis-based risk indices alone are insufficient strategies for the quantification of a PH1 patient's CaOx crystallization risk.
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PMID:Problems in the investigation of urine from patients suffering from primary hyperoxaluria type 1. 1615 74

In primary hyperoxaluria the deficiency or mistargeting of hepatic alanine-glyoxylate aminotransferase (AGT) leads to the overproduction of oxalate resulting in hyperoxaluria and renal damage due to urolithiasis and/or nephrocalcinosis. Presently, the cure of the metabolic defect can be achieved only by liver transplantation. While for patients with end-stage renal disease combined hepatorenal transplantation is recommended, the concept of preemptive liver transplantation (PLTX), i.e. cure of the metabolic defect before renal damage occurs, has received considerable attention. Due to the heterogenous clinical course in PH1, optimal timing of PLTX is a matter of debate. Advocators of PLTX would consider a patient with a slowly declining GFR, reaching levels of 40-60 ml/min/1.73 m(2), as an ideal candidate, while others would continue medical treatment in these patients and opt for rapid combined liver-kidney transplantation if GFR reaches even lower levels. This review will discuss the background and rationale of PLTX and gives an update on 11 patients with PLTX who have been reported in the literature to date.
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PMID:The role of preemptive liver transplantation in primary hyperoxaluria type 1. 1628 78

The primary hyperoxalurias are rare, inherited diseases which commonly manifest early in life as urolithiasis. As these patients often present to the urologic surgeon, it is imperative that urologists understand the typical presentation, diagnosis, and management of urolithiasis associated with primary hyperoxaluria. In this review, the pertinent epidemiology and pathogenesis as they relate to the diagnosis and natural history of the disease are discussed. The literature on therapeutic options for primary hyperoxaluric patients with calculi is examined, and treatment strategies are suggested.
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PMID:Pitfalls in the management of patients with primary hyperoxaluria: a urologist's perspective. 1628 85


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