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)

Primary hyperoxaluria type I (PHI) is a cause of end-stage renal disease in young people. It is caused by deficient activity of hepatic peroxisomal alanine:glyoxylate aminotransferase (AGT), which results in hyperoxalemia and hyperoxaluria. The consequent urolithiasis and nephrocalcinosis result in renal impairment, with further reduction in oxalate excretion and eventual systemic oxalosis. Historically, renal transplantation has yielded very poor results in these patients because of recurrent oxalosis of the graft. Within the last 10 years, combined hepatorenal transplantation has been successfully applied, simultaneously correcting the metabolic lesion in the liver and replacing the damaged kidneys. It has, however, become apparent that medical therapy with vigorous hydration, inhibitors of stone formation and pyridoxine (AGT co-factor), may be successful at delaying, and occasionally in preventing, urolithiasis in some hyperoxaluric patients, particularly those whose hyperoxaluria is reduced by pyridoxine. This, together with intensive perioperative management and modern surgical methods of stone management such as lithotripsy, laser or ultrasound stone fragmentation, and percutaneous nephrolithotomy, means that renal transplantation alone may be feasible in selected patients. We describe a patient with PHI with clinical and biochemical evidence of significant residual AGT activity who underwent a successful live-related renal transplantation with excellent renal function and no stone recurrence 1 year posttransplantation. The appropriate transplantation strategies for these complex patients are discussed and include isolated renal transplantation for those patients who are without significant systemic oxalosis and have evidence of residual AGT activity.
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PMID:Selective renal transplantation in primary hyperoxaluria type 1. 865 Dec 56

Considering the clinical heterogeneity of primary hyperoxaluria type I (PH1) and the fact that in many instances this diagnosis was made without enzymatic and immunohistochemical investigation, other disturbances of oxalate metabolism than those presently known can be expected in PH1. Using a gaschromatographic/mass spectrometric method that allows quantification of these acids, hyperoxaluria and hyperglycoluria was found repeatedly in two unrelated patients. The hyperoxaluria was unresponsive to pyridoxine. There was no nephrocalcinosis or urolithiasis. In the liver biopsy normal AGT activity and normal localization of this enzyme in the peroxisome was found. In one patient abnormal Km and maximal activity and mozaicism of AGT were excluded. Hyperoxaluria and hyperglycoluria were also found in other family members, suggesting autosomal dominant transmission. Although the underlying defect leading to hyperoxaluria and hyperglycoluria could not be identified in these patients, it is probable that they represent a separate type of primary hyperoxaluria.
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PMID:Hyperoxaluria with hyperglycoluria not due to alanine:glyoxylate aminotransferase defect: a novel type of primary hyperoxaluria. 891 45

To determine reference values, we studied urinary excretion of oxalate prospectively and longitudinally in a cohort of 23 very-low-birth-weight (VLBW) infants. The urinary oxalate concentrations were evaluated in 24-hour urine samples by the oxalate oxidase method. Urine samples were obtained at 1, 2-3, 4-5 and 6-7 weeks of age. The median oxalate amount was 24 mumol/kg body weight/day with a 10th-90th percentile range of 16-45 in the 1st week. Oxalate excretion was highest in 2- to 3-week-old infants (median: 35; percentile range: 26-56 mumol/kg body weight/day). In the 4th-5th week, the median was 24 (percentile range: 15-47) mumol/kg body weight/day and in weeks 6-7 also 24 (percentile range: 10-36) mumol/ kg body weight/day. Also, the urinary oxalate concentration as well as the oxalate-creatinine ratio showed increased values in the first 3 weeks of life and decreased values afterwards. In a multivariate analysis, nutrition or gestational age did not affect the urinary oxalate concentration, the daily amount excreted or the oxalate-creatinine ratio. The investigated parameters (oxalate amount and oxalate-creatinine ratio in urine) were significantly age dependent). The data show that urinary oxalate excretion in VLBW infants approaches levels that are in the same range as those of patients with urolithiasis. Thus the risk of nephrocalcinosis in VLBW infants may be increased.
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PMID:Oxalate excretion during the first 7 weeks in very-low-birth-weight infants. 916 48

We report on 24 children (10 girls) presenting with primary hyperoxaluria. The mean age at diagnosis was 6.3 years (range: 3 months-14.8 years). The mean interval between initial symptom and diagnosis was 1.3 year. The average follow-up period was 22 months (range: 1-60 months). At the time of diagnosis the renal function was normal in 6 children, moderately altered in 1 and severely in 17. During the follow-up the renal function remained stable in 6 patients, improved in 2, deteriorated in 4. The 12 patients with end-stage renal disease at diagnosis remained unchanged. Urolithiasis were present in all patients older than 2 years, and in 1 among the 5 infants. Medullary nephrocalcinosis was observed in 3 patients in whom the renal function was preserved. Diffuse nephrocalcinosis was present in all patients with end-stage renal failure. Improvement of renal function was secondary to stone removal in 2 patients. Extracorporeal shock wave lithotripsy performed in 7 patients was efficient only in 3. In 10 patients oxalate bone disease was correlated with both renal function and dialysis duration, whereas retinal involvement noted in 6 patients was not.
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PMID:[Primary hyperoxaluria: Tunisian experience apropos of 24 pediatric cases]. 918 35

Hypercalciuria is a rare biological symptom with multiple possible etiologies in children. Normal calcium excretion rate in children is defined as lower than 4 mg/kg per day, significantly higher values being observed in infants. When using urinary calcium: creatinine ratio, normal values are below 0.22 mg/mg in children, and below 0.6 to 0.8 mg/mg in infants. In our experience half patients with hypercalciuria have idiopathic hypercalciuria. Idiopathic hypercalciuria can be hereditary with a dominant autosomal mode of inheritance. Its pathophysiology is unclear, increased calcium intestinal absorption and impaired renal tubular calcium reabsorption being the two main underlying anomalies. Patients with hypercalciuria should be informed about the risk of urolithiasis and its possible prevention by a high water intake. In those patients with nephrocalcinosis or recurrent episodes of lithiasis, hydrochlorothiazide can be effective in reducing hypercalciuria. However, adverse effects of hydrochlorothiazide on serum lipids have been recently reported and make this treatment questionable in the long term.
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PMID:[Hypercalciuria: etiologies and treatment]. 918 9

The routine use of ultrasonography has resulted in an explosion in the number of conditions reported to be associated with nephrocalcinosis. It has also been increasingly recognized that urolithiasis and nephrocalcinosis can coexist in the same patient. The two conditions most commonly associated with nephrocalcinosis in childhood are the use of furosemide in infancy and the treatment of patients with hypophosphatemic rickets with phosphate and vitamin D preparations. Although originally thought to be related to hypercalciuria, more recent studies in humans and research animals indicate a multifactorial etiology for furosemide-related nephrocalcinosis. In patients with hypophosphatemic rickets, it seems that the dose of phosphate and in particular the development of secondary hyperparathyroidism play a central role in the development of nephrocalcinosis. Among the entities recently reported to be associated with nephrocalcinosis are some that characteristically include Fanconi's syndrome. These findings dispute the previous teaching of lack of renal calcifications in this syndrome, which involves proximal renal tubular acidosis. The diagnosis of nephrocalcinosis requires a metabolic work-up to identify the offending factor. When identified, appropriate intervention should be instituted.
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PMID:Nephrocalcinosis. 920 44

Urolithiasis and/or nephrocalcinosis due to hereditary diseases are a rare event which must be kept in mind of physicians who take care of children (10 to 40% of all causes of lithiases) as well as of adults (less than 15% of all causes of lithiases) since a specific management is usually required. The most frequent inborn disorders are idiopathic hypercalciuria, distal tubular acidosis, cystinuria and hyperoxaluria. Stone formation is always secondary to an increased urine concentration of promotors, i.e. calcium, oxalate, phosphate, cystine, xanthine. One of the most informative diagnosis investigation is infrared spectrophotometry which can identify stone composition. When such a technique is not available, biochemical investigations should be adapted to both personal and family history. In addition to high fluid intake (2 to 3 L/m2/24 h) sometimes associated with alcalinisation, the management of hereditary stone disease requires specific procedure. In all cases, the long-term renal prognosis is related to both primary disease and therapeutic compliance.
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PMID:[Hereditary diseases causing kidney calculi]. 936 14

We report three new Kuwaiti patients with carbonic anhydrase II deficiency (CA II) from two unrelated families. Each patient had osteopetrosis, distal renal tubular acidosis, and cerebral calcification. Patients from family 1 (a brother and a sister) had some facial anomalies and delayed development. At the age of 14 months, ultrasound studies in the girl showed medullary nephrocalcinosis which has not been previously described in association with CA II, while cerebral CT scan revealed dilated ventricles. The patient from family 2, who had two previously reported affected siblings, developed bilateral recurrent renal stones and hypercalciuria but no nephrocalcinosis. None of his affected siblings had nephrocalcinosis or urolithiasis. DNA analysis of patients from both families showed that each of them was homozygous for the "Arabic" mutation in the CA II gene. We report new features in three Arab patients with CAII deficiency. Also review all previously reported CA II cases from Kuwait in order to highlight the inter-/intra-familial variability of the disease in this part of the world despite the overwhelming prevalence of the same "Arabic" mutation among the patient population.
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PMID:Nephrocalcinosis and urolithiasis in carbonic anhydrase II deficiency syndrome. 945 81

Patients with cystic fibrosis (CF) have an increased risk of urolithiasis/nephrocalcinosis. To determine potential mechanisms responsible, we studied the urinary excretion of lithogenic and stone-inhibitory substances and calculated the urinary saturation for calcium-oxalate (CaOx), brushite (CaHPO4), and uric acid (UA). We examined 24-h urines in 63 patients with CF (34 female, 29 male) aged 5 months to 36 years. Renal ultrasonography was performed at the time of urine collection. Hyperoxaluria was found in 25 patients (range 0.51-1.71 mmol/1.73 m2 per 24 h). Urinary Ca was increased in 13 patients (4.1-8.22 mg/kg per 24 h). Hyperuricosuria was found in 16 patients (5.2-18.0 mmol/1.73 m2 per 24 h) and hypocitraturia in 14 patients (0.07-1.14 mmol/1.73 m2 per 24 h). CaOx saturation was elevated in 26 patients, related to hyperoxaluria in 19 patients. CaHPO4 saturation was increased in 19 patients and UA saturation in 11 patients. Urolithiasis in situ was diagnosed in 1 patient; 3 patients previously had renal stones; 4 patients had present nephrocalcinosis. Elevated excretion of lithogenic substances and urinary supersaturation might lead to the higher risk of urolithiasis/nephrocalcinosis in patients with CF.
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PMID:Urinary excretion substances in patients with cystic fibrosis: risk of urolithiasis? 965 56

The two most common causes of hypercalcemia are malignancy and primary hyperparathyroidism (1 degree HPT). The radiographic presentations and the histological findings on bone biopsy are important for differential diagnosis of underlying diseases. We report a patient with hypercalcemia who presented unusual bone manifestations. A 43 y/o woman was admitted due to right femoral fracture. X-ray on the right tibia revealed several osteolytic cystic lesions with sclerotic rims. Blood biochemistry showed anemia, impaired renal function and hypercalcemia. Multiple osteolytic lesions on the skull and bilateral forearms were also noted. Malignancy, such as multiple myeloma or metastatic cancer was suspected. However, this was excluded because of the absence of M-component on serum protein electrophoresis and the negative finding of plasma cells or other malignant cell on bone biopsy examination. Abdominal sonography demonstrated bilateral medullary nephrocalcinosis. The final diagnosis of 1 degree HPT was made, based on the findings of classic pathological pictures (brown tumor) and the markedly elevated intact parathyroid hormone (1267.4 pg/ml) level. Sonography on the neck and 201Tl/99mTc parathyroid subtraction scan localized a left lower parathyroid tumor and fine needle aspiration confirmed the parathyroid origin. Diagnosis of 1 degree HPT could only be made from recurrent urolithiasis and X-ray picture of osteitis fibrosa cystica in the past. This patient presented the full-blown skeletal changes which are uncommonly seen nowadays. The characteristic sclerotic rims suggesting increased bone formation provides a further important clue for differential diagnosis of 1 degree HPT from other malignancies with osteolytic bone lesions.
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PMID:A patient of primary hyperparathyroidism with full-blown bone changes simulating malignancy. 979 3


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