Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.4.2.7 (adenine phosphoribosyltransferase)
 692 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Inherited metabolic diseases resulting in urolithiasis secondary to urinary excretion of insoluble substances are rare but often present as urinary obstruction of renal insufficiency. We herein report a case of partial adenine phosphoribosyltransferase deficiency associated with 2,8-dihydroxyadenine urolithiasis. In family members the propositus and his younger brother are homozygotes for defective APRT genes, and who exhibits the type II phenotype designated APRT*J (Japanese type).
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PMID:2,8-Dihydroxyadenine urolithiasis due to partial deficit in adenine phosphoribosyltransferase: a case report. 160 69

Disorders of purine metabolism are well recognized clinical entities in modern medical practice. However, there are lesser known aberrations of purine and pyrimidine metabolism that can manifest as disease states. Deficiency of the enzyme adenine phosphoribosyltransferase is an autosomal recessive inherited disorder resulting in 2,8-dihydroxyadenuria, and possible urolithiasis and renal insufficiency. A woman with a pure 2,8-dihydroxyadenine ureteral calculus is reported, who represents the third reported case in the United States. Stones comprised of 2,8-dihydroxyadenine are difficult to distinguish from uric acid clinically, making sophisticated crystallographic analysis essential for accurate diagnosis. Treatment differs from that appropriate for uric acid lithiasis due to the limited solubility of 2,8-dihydroxyadenine at pH levels of less than 9. Prevention requires purine restriction and allopurinol.
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PMID:2,8-Dihydroxyadenine urolithiasis: report of a case in a woman in the United States. 274 54

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

The purpose of this study was to characterize the clinical, diagnostic, and prognostic features of adenine phosphoribosyltransferase (APRT) deficiency in Icelandic patients, as well as determine their genotype. Medical records of all known patients in Iceland were reviewed. Urinalysis and polymerase chain reaction-based DNA mutation analysis were performed in all patients, siblings, and living parents of index cases. Twenty-three individuals homozygous for type I APRT deficiency were identified in 16 families from 1983 to 1998. There were 12 males and 11 females, and the median age at diagnosis was 37 years (range, 0.5 to 62 years). Seventeen patients were index cases and 6 patients were diagnosed during screening of first-degree relatives. Eighteen patients had symptomatic disease, 15 of whom experienced nephrolithiasis; 4 patients had mild to moderate renal insufficiency, 1 patient had advanced renal failure, and 1 patient died of uremic complications. Six patients experienced recurrent urinary tract infections and 3 infants had a history of reddish-brown diaper stains. Five patients were asymptomatic; 3 of these patients were diagnosed during routine urinalysis and 2 patients were identified during family screening. Urinary 2,8-dihydroxyadenine crystals were detected in all cases, except for the patient who died of end-stage renal failure. All 23 patients were homozygous for the same mutation (D65V) in the APRT gene. Allopurinol therapy successfully prevented further stone formation and significantly improved renal function in most patients with renal insufficiency. Our results suggest that APRT deficiency may be more common than previously recognized and can lead to severe renal failure if left untreated.
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PMID:Clinical features and genotype of adenine phosphoribosyltransferase deficiency in iceland. 1153 77