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)

More than half of the Japanese patients with 2,8-dihydroxyadenine urolithiasis only partially lack adenine phosphoribosyltransferase (APRT), while all the Caucasian patients with the same disease completely lack the enzyme. APRT activities in healthy heterozygotes for the complete APRT deficiencies were at the same levels as the Japanese patients, and simple enzyme assay does not distinguish between these two conditions. We have previously shown, using viable T-cells, that the enzyme was non-functional in the cells from the Japanese patients although they contain considerable APRT activities in the cell extracts. In the present investigations, we devised a rapid method using erythrocytes for the diagnosis of partial APRT deficiencies accompanied by severe impairment in adenine metabolism causing 2,8-dihydroxyadenine lithiasis. Thus, erythrocytes from three different families with 2,8-dihydroxyadenine urolithiasis associated with partial APRT deficiencies incorporated only minimal amounts of radioactive adenine, while normal erythrocytes incorporated significant amounts. These data indicate that severe impairment in adenine metabolism is shown not only in viable T-cells but also in viable erythrocytes. The present procedures provide a rapid method suitable for routine clinical use for the diagnosis of partial APRT deficiencies causing 2,8-dihydroxyadenine lithiasis.
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PMID:Rapid method for the diagnosis of partial adenine phosphoribosyltransferase deficiencies causing 2,8-dihydroxyadenine urolithiasis. 404 67

Ninety-seven male patients with idiopathic calcium urolithiasis and 17 normal male subjects were studied to evaluate the mechanism of idiopathic hypercalciuria with an oral calcium tolerance test, which has been useful in differentiating hypercalciuria. The changes in parathyroid function, such as parathormone and urinary cyclic AMP, and calcium after calcium load differed between absorptive hypercalciuria and renal hypercalciuria. We have confirmed that the change in serum calcitonin after calcium load was also different in these two hypercalciurias. The increase in serum calcium was sufficient to reduce parathyroid function but serum calcitonin was unchanged after calcium load in the control group, in patients with normocalciuria, and those with renal hypercalciuria. Although serum and urinary calcium were more elevated in absorptive hypercalciuria than in the other three groups, parathyroid function was not significantly reduced after loading in absorptive hypercalciuria. In this group only, the serum calcitonin was significantly elevated after calcium load. It is reasonable to suggest that, in this group, because parathyroid function is usually suppressed by intestinal hyperabsorption of calcium, parathyroid function may not be further suppressed by even calcium load. Possibly the significant stimulation of calcitonin may compensate for the lack of suppression of parathyroid function and maintain normal serum calcium levels in absorptive hypercalciuria. These results suggest that the change in serum calcitonin is also useful to differentiate abnormalities of calcium metabolism in patients with hypercalciuria.
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PMID:Oral calcium tolerance test and serum calcitonin in calcium stone formers. 630 68

A group of 121 patients with a history of multiple or complicated calcium urolithiasis were divided into three subgroups: normal, absorptive and renal/resorptive calciuria by means of a calcium-loading test. Patients with renal hypercalciuria had lower bone mineral content (BMC) than the other groups but did not differ in amount of bone or TmPO4/GFR. The 24-hour urine calcium excretion was elevated in patients with renal and absorptive type of hypercalciuria but not in patients with normal calcium-loading test and there was no correlation to BMC. The c-AMP/creatinine seemed to discriminate patients with resorptive calciuria from patients with renal calciuria. It is suggested that only patients with renal hypercalciuria should be treated with calcium-retaining drugs such as thiazides.
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PMID:Calcium-loading test and bone disease in patients with urolithiasis. 665 69

Outpatient renal stone formers belonging to the established urolithiasis subgroups and controls were examined with respect to urinary and serum citrate (Cit) and several associated variables. Only in the normocalciuric majority of calcium and in uric acid stone formers was Cit in 24-hour urine decreased, but was normal in 2-hour fasting morning, and in 3-hour postprandial urine following a Cit-free test meal. Serum Cit was elevated in normocalciuria, renal and resorptive hypercalciuria. This Cit constellation was associated with either normal (absorptive, renal hypercalciuria) or low (normocalciuria, uric acid stone formers) parathyroid gland function as assessed by serum parathyroid hormone and nephrogenous urinary cyclic AMP, except in patients with primary hyperparathyroidism. In 2-hour morning urine the magnesium/creatinine ratio (normocalciuria) and ammonia excretion (uric acid stone formers) were decreased, while ammonia in 24-hour urine was low in all stone formers. It is suggested that Cit metabolism is altered in renal stone disease in general, and that in normocalciuria, stone inhibitors (Cit; magnesium) may be deficient.
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PMID:Citrate in urine and serum and associated variables in subgroups of urolithiasis. Results from an outpatient stone clinic. 712 65

APRT deficiency may be totally benign or life threatening. The importance of early recognition/diagnosis is thus stressed. Urolithiasis (2,8-DHA stones: the precipitating factor in all cases) is treatable. With early recognition and treatment allopurinol without alkali and a diet low in purine homozygotes have remained clinically and biochemically normal to date. 'Uric acid' stones in children must always be suspect and subjected to sophisticated analysis. Diagnosis from red cell APRT activity may also have its pitfalls.
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PMID:Spectrum of 2,8-dihydroxyadenine urolithiasis in complete APRT deficiency. 742 54

We analyzed DNA from six Japanese patients with adenine phosphoribosyltransferase (APRT) deficiency who developed 2,8-dihydroxyadenine (DHA) urolithiasis. These six patients were selected for DNA analysis since they were expected to possess allele(s) with mutations other than two known abnormalities, i.e. a missense mutation at codon 136 (APRT*J allele) and a nonsense mutation at codon 98. In three of the six patients an insert of four bases CCGA was detected in exon 3 by sequencing clones obtained from the genomic DNA. In two of the three patients, both of the two alleles had this mutation (homozygotes) while the other patient had the APRT*J allele in addition to the allele with the 4-base insertion. To search for mutations other than the above three defined germline mutations, we amplified a genomic DNA segment including all the 5 exons of the APRT gene by PCR and cloned it into a plasmid. After selecting recombinant plasmids containing neither of the three defined mutations, we sequenced the entire APRT exons and introns. Abnormalities were found in neither the coding regions nor the exon-intron junctions. Disease-related mutations in these mutant alleles may exist in either 5' or 3' flanking sequences and remain to be elucidated.
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PMID:Detection of the three common mutations of adeninephosphoribosyltransferase deficiency among Japanese. 775 7

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

We treated two children with 2,8-dihydroxyadenine urolithiasis for over 7 years. The male prepositus was admitted to the hospital because of anuria when he was 10 months old. Bilateral urinary stones had caused the anuria. The stones were 2,8-dihydroxyadenine and his APRT activity was low. He has been treated with about 5.0 mg/kg/day of allopurinol without purine diet restriction. His sister, 3 years old at that time, also was found to have a renal stone. She has been treated with about 3.3 mg/kg/day of allopurinol without restricting purine. The allopurinol therapy without purine-restriction resulted in normal growth of both children with neither the recurrence of stone nor renal impairment.
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PMID:[Two siblings with 2,8-dihydroxyadenine urolithiasis]. 786 62

We describe a family of Turkish origin with adenine phosphoribosyltransferase (APRT) deficiency and renal stone disease. The proband had 2,8-dihydroxyadenine urolithiasis but an older sister, who was also deficient in enzyme activity, is so far asymptomatic. The proband was homozygous for a 7-bp deletion in exon 3 of the APRT gene. One allele from each of the parents also contained this deletion. The patient and her father were homozygous for an intragenic TaqI RFLP (1.25-kb fragment) whereas the mother was heterozygous (1.25- and 1.91-kb fragments), indicating that the mutation was present on the allele carrying the 1.25 kb TaqI fragment. The deletion alters the reading frame downstream of codon 93 and would be expected to abolish enzyme activity.
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PMID:Identification of a 7-basepair deletion in the adenine phosphoribosyltransferase gene as a cause of 2,8-dihydroxyadenine urolithiasis. 798 85

We report a case of adenine phosphoribosyltransferase deficiency in which the initial presentation was chronic renal failure. Diagnosis was made after infrared microscopy analysis of microcrystalline deposits on a kidney allograft biopsy specimen. This type of presentation is rarely seen, the most frequent manifestation of this disease being urolithiasis. This is the first report of recurrence of the microcrystalline nephritis in a kidney transplant with subsequent loss of allograft function.
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PMID:Chronic renal failure secondary to 2,8-dihydroxyadenine deposition: the first report of recurrence in a kidney transplant. 802 15


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