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)

In a patient with xanthine urolithiasis secondary to hereditary xanthinuria (xanthine oxidase deficiency), allopurinol administration resulted in a 20 per cent increase in oxypurine excretion and an elevation of the urinary xanthine/hypoxanthine ratio from 4.08 to 6.53. The rise in this ratio suggests that residual xanthine oxidase activity may have been present. It is possible that the excessive re-utilization of hypoxanthine and xanthine in this disease prevents the allopurinol-induced inhibition of de novo purine biosynthesis that is seen in normal subjects.
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PMID:The effect of allopurinol on oxypurine excretion in xanthinuria. 95 Jun 37

A 74-year-old female with hereditary xanthinuria and xanthine stones is reported. She has a family history of consanguineous parents and a past history of right side nephrectomy due to a xanthine renal stone and vesicolithotomy of 3 bladder stones approximately 5 X 4 X 4 cm in size at the age of 58 and 71, respectively. Her young brother exhibited a slightly elevated urinary excretion of oxypurines. Laboratory examination showed a low serum level (0.3 mg/dl) and urinary excretion (1.56 mg/day) of uric acid, and high plasma and urine levels of oxypurines. No xanthine oxidase activity was detectably in duodenal mucosa by biopsy specimen obtained by duodenofiberscopy. Now she has another stone approximately 5 X 4 X 4 cm in her bladder. There have been are few elderly cases of hereditary xanthinuria with recurrent giant urolithiasis.
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PMID:[An aged case of hereditary xanthinuria with xanthine urinary calculi]. 204 68

Inherited adenine phosphoribosyltransferase (APRT) has a recessive transmission. When it is very important, adenine can't be restored into nucleic acids pool and will changed into 2,8-dihydroxyadenine (2,8-DHA) by xanthine oxidase. To date in all countries but Japan, 2,8-DHA urolithiasis is observed only into homozygotic subjects with complete APRT deficiency Commonly, its onset is observed in childhood often dramatically. The authors report two new pediatric cases into new french families. First a 8 years old boy with spontaneous elimination of two lithiasis after right lumbar pain. Secondly an infant (nineteen months) who has presented an acute renal failure with anuria. Bilateral lithiasis included into pyelourectal junctions have been pulled out by bilateral surgical pyelotomy. In each case, lithiasis were radiolucent and diagnosis made by ultrasonography. The uric acid metabolism was normal and it is the infra red spectrophotometric study of stones that had recognised the 2,8-DHA component. In the second case, bilateral residual lithiasis have been broken by piezoelectric extra-corporeal lithotripsy with good tolerance and favorable result. The two children received preventive treatment. After 36 and 19 months they have no recurrence. In the literature, the frequency of 2,8-DHA lithiasis is very more low than the theoretical of homozygotics in population (1/100,000). The common confusion with uric lithiasis is one possible explanation. So spectrophotometric study of radiolucent stones was meant to be realised when uric metabolism is not disturbed.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[2,8-dihydroxyadenine lithiasis. 2 new pediatric cases of an unknown metabolic deficit. The use of extracorporal lithotripsy]. 238

We report the first patient in Finland and Scandinavia with a deficiency of adenine phosphoribosyltransferase (APRT). About 30 clinically affected patients have been reported in the literature. APRT deficiency is an enzyme disorder which is inherited autosomally in a recessive manner. The use of adenine in purine metabolism is disturbed and it accumulates in the body, where it is oxidised to poorly insoluble 2,8-dihydroxyadenine by xanthine oxidase. The dihydroxyadenine forms stones which can be mistaken for uric acid stones. Our patient had had frequent episodes of urolithiasis and the diagnosis was finally made after pyelolithotomy and stone analysis. The total APRT deficiency was detected in the haemolysate of erythrocytes. Partial deficiency of APRT in the patient's relatives showed heterozygosity of the enzyme defect. The only clinical manifestation of the defect is the formation of urinary stones. This can be prevented by diet and allopurinol.
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PMID:Adenine phosphoribosyltransferase deficiency: 2,8-dihydroxyadenine urolithiasis in a 48-year-old woman. 280 78

Allopurinol (4-hydroxypyrazolo (3,4-d)-pyrimidine) is a potent xanthine oxidase inhibitor which inhibits the oxidation of naturally occurring oxypurines, thus decreasing uric acid formation. The clinical and metabolic effects of this agent were studied in 80 subjects with primary and secondary gout and other disorders of uric acid metabolism. Allopurinol has been universally successful in lowering the serum uric acid concentration and uric acid excretion to normal levels, while not significantly affecting the clearance of urate or other aspects of renal function. Oxypurine excretion increased concomitantly with the fall in urine uric acid. The agent is particularly valuable in the management of problems of gout with azotemia, acute uric acid nephropathy and uric acid urolithiasis. The minor side effects, clinical indications and theoretical complications are discussed.
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PMID:The treatment of gout and disorders of uric acid metabolism with allopurinol. 592 71

APRT deficiency is an enzyme disorder which is inherited as an autosomal recessive trait. The use of adenine in purine metabolism is disturbed and it accumulates in the body, where it is oxidised by xanthine oxidase to poorly insoluble 2, 8-dihydroxyadenine (DHA). The dihydroxyadenine forms stones which cause recurrent urolithiasis, frequent episodes of urinary tract infection or interstitial nephritis, and finally renal insufficiency in some cases. We report a case of APRT deficiency discovered by urine examination. The patient was a 33-year-old man who had never had any episodes of urolithiasis. He was admitted to our hospital because of pseudoarthrosis of his left arm caused by a traffic accident. His urinalysis revealed no proteinuria nor hematuria, but disclosed numerous round brown crystals in the sediment. These crystals had the characteristics of 2, 8-DHA. The enzyme activity of APRT in his blood was completely deficient. He was diagnosed as an APRT* QO homozygote. In addition, diagnostic imaging revealed that his right kidney was poorly hypoplastic and the pelvis of his left kidney was extra-renal. The renal function was slightly disturbed. In Japan 6 cases of 2, 8-DHA urolithiasis associated with hypoplastic kidney had been reported by 1989. Theoretically, the incidence of hypoplastic kidney is around 20% of all 2, 8-DHA urolithiasis cases. We suspect a genetic correlation between hypoplastic kidney and APRT deficiency. This patient was treated with Allopurinol, which inhibits the process of xanthine oxidation, after which crystals were no longer detected in his urine.
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PMID:[A case of adenine phosphoribosyltransferase (APRT) deficiency discovered by urine examination]. 781 52

Xanthine calculi were found in a 7-month-old male Cavalier King Charles spaniel with urethral obstruction and renal insufficiency. Because the only two other reported cases of naturally occurring xanthine urolithiasis concerned a Cavalier King Charles and a King Charles spaniel the urine of the littermates and parents of the patient were also examined for xanthinuria. Semi-quantitative analysis revealed high urine concentrations of hypoxanthine and xanthine in the patient and his female littermate. Quantitative analysis by high-pressure liquid chromatography (HPLC) of the urine samples from the family of this Cavalier King Charles spaniel and nine control dogs revealed that hypoxanthine and xanthine excretion was 30 and 60 times higher in the affected patient and the female littermate than in the others dogs. The pattern of xanthinuria, which is caused by a deficiency of the enzyme xanthine oxidase, in the relation diagram of this family of Cavalier King Charles Spaniels was consistent with an autosomal recessive mode of inheritance.
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PMID:Xanthinuria in a family of Cavalier King Charles spaniels. 941 15

Uric acid (UA), a waste product of purine metabolism, may be involved in calcium phosphate crystallization and deposition. Rats, which develop nephrocalcinosis on high-fat or magnesium-deficient diets, and patients with idiopathic calcium urolithiasis have hyperproteinuria, especially of nonalbumin protein, and a shift toward elevated serum UA. In rats, an increase in UA precursors and renal UA suggests hypoxemia, which stimulates xanthine oxidase. In patients, a primary increase in renal xanthine oxidase would explain the low urine UA in the presence of an elevated serum concentration. For calcium phosphate deposition (rats) or incorporation into stones (humans) to occur, a crucial factor may be xanthine oxidase-mediated overproduction of free radical species and subsequent tissue damage. Another factor may be whether sufficient UA is synthesized to neutralize these free radicals. Allopurinol use, which inhibits xanthine oxidase and has long been favored for the treatment of idiopathic calcium urolithiasis, may not prevent stones, because it also diminishes the availability of UA. An investigation of the factors that control serum UA homeostasis may be rewarding in research into the etiology of idiopathic calcium urolithiasis.
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PMID:Is there a role for uric acid in an animal model of calcium phosphate nephrocalcinosis and calcium phosphate crystallization in urine of patients with idiopathic calcium urolithiasis? An orientational study. 1060 15

Membrane injury facilitated the fixation of calcium oxalate crystals and subsequent growth into kidney stones. Oxalate-induced membrane injury was mediated by lipid peroxidation reaction through the generation of oxygen free radicals. In urolithic rat kidney or oxalate exposed cultured cells, both superoxide anion and hydroxyl radicals were generated in excess, causing cellular injury. In hyperoxaluric rat kidney, both superoxide and H2O2-generating enzymes such as glycolic acid oxidase (GAO) and xanthine oxidase (XO) were increased, and hydroxyl radical and transition metal ions, iron, and copper were accumulated. The lipid peroxidation products, thiobarbituric acid-reactive substances (TBARS), hydroperoxides, and diene conjugates were excessively released in tissues of urolithic rats and in plasma of rats as well as stone patients. The accumulation of these products was concomitant with the decrease in the antioxidant enzymes, superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), and glucose-6 phosphate dehydrogenase (G6PD) as well as radical scavengers, vitamin E, ascorbic acid, reduced glutathione (GSH), and protein thiol. All the above parameters were decreased in urolithic condition, irrespective of the agents used for the induction of urolithiasis. Oxalate binding activity and calcium oxalate crystal deposition were markedly pronounced, along with decreased adenosine triphosphatase (ATPase) activity. Lipid peroxidation positively correlated with cellular oxalate, oxalate binding, gamma-glutamyl carboxylase, and calcium level and negatively correlated with GSH, vitamin E. ascorbic acid, and total protein thiol. Antioxidant therapy to urolithic rats with vitamin E, glutathione monoester, methionine, lipoic acid, or fish oil normalised the cellular antioxidant system, enzymes and scavengers, and interrupted membrane lipid and protein peroxidation reaction, ATPase inactivation, and its associated calcium accumulation. Antioxidant therapy prevented calcium oxalate precipitation in the rat kidney and reduced oxalate excretion in stone patients. Similarly, calcium oxalate crystal deposition in vitro to urothelium was prevented by free radical scavengers such as phytic acid and mannitol by protecting the membrane from free radical-mediated damage. All these observations were suggestive of the active involvement of free radical-mediated lipid peroxidation-induced membrane damage in the pathogenesis of calcium oxalate crystal deposition and retention.
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PMID:Calcium oxalate stone disease: role of lipid peroxidation and antioxidants. 1194 24

There are three stages in the management of gout: (i) treating the acute attack; (ii) lowering excess stores of uric acid to prevent flares of gouty arthritis and to prevent tissue deposition of urate; and (iii) providing prophylaxis to prevent acute flares. It is important to distinguish between therapy to reduce acute inflammation in acute gout and therapy to manage hyperuricaemia in patients with chronic gouty arthritis. During the acute gouty attack nonpharmacological treatments such as topical ice and rest of the inflamed joint are useful. NSAIDs are the preferred treatment in acute gout. The most important determinant of therapeutic success is not which NSAID is chosen, but rather how soon NSAID therapy is initiated. Other treatments include oral and intravenous colchicine, intra-articular and systemic corticosteroids, and intramuscular corticotropin. Optimal treatment of chronic gout requires long-standing reduction in serum uric acid. The urate-lowering drugs used to treat chronic gout are the uricosuric drugs, the uricostatic drugs, which are xanthine oxidase inhibitors, and the uricolytic drugs. Xanthine oxidase inhibitors such as allopurinol, oxipurinol and febuxastat should be used as first-line treatment in patients with renal calculi, renal insufficiency, concomitant diuretic therapy and ciclosporin (cyclosporine) therapy, and urate overproduction. Uricosuric drugs include probenecid, benzbromarone, micronised fenofibrate and losartan. They are the urate-lowering drugs of choice in allopurinol-allergic patients and underexcretors with normal renal function and no history of urolithiasis. The use of recombinant urate oxidase in patients with chronic gout is limited by the need for parenteral administration, the potential antigenicity and production of anti-urate oxidase antibodies, and declining efficacy. The effectiveness of colchicine prophylaxis as an isolated therapy is still to be confirmed by placebo-controlled trials. Another issue is prophylaxis with NSAIDs. There are no comparative studies with colchicine.
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PMID:Management of acute and chronic gouty arthritis: present state-of-the-art. 1548 99


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