Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020438 (hypercalciuria)
 2,502 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report herein data on 6 male patients with progressive tubulopathy. These patients belonged to two families: the propositus, his father, a paternal first cousin, two paternal uncles, and a maternal uncle. A 7-year-old proband had mild proteinuria (1 g/day), consisting of beta 2-microglobulin, alpha 1-microglobulin and lysozyme, and aminoaciduria. Glycosuria and acidosis were absent. A 38-year-old father had mild proteinuria (2 g/day), including low-molecular-weight protein. Hypokalemia, hypophosphatemia, glucosuria, phosphaturia, aminoaciduria, and reduced urinary concentrating ability were also present. The other 4 affected family members also had low-molecular-weight proteinuria, detected by screening for beta 2-microglobulin. In addition, there were several abnormalities; aminoaciduria in all 6, phosphaturia in 4 of 6, hypercalciuria in all 6 and glycosuria in 2 of 6 patients. Tubular dysfunction was more severe in the older subjects, hence, the disease seems to progress with age. Familial low-molecular-weight proteinuria is apparently a progressive disease linked to a X-linked or to an autosomal dominant inheritance.
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PMID:Familial progressive renal tubulopathy. 158 58

To investigate whether overall tubular dysfunction is encountered in a particular subgroup of patients with urolithiasis, the following parameters of renal tubular function have been measured in fasting morning urine in 124 male stone formers: excretion of lysozyme and gamma-glutamyl transpeptidase (gamma-GT), fractional excretion (FE) or glucose, insulin, bicarbonate after an alkali load, and theoretical phosphate threshold (TmP/GFR). The following have been diagnosed: primary hyperparathyroidism (n = 3), medullary sponge kidneys (n = 5), hyperuricemia (n = 8), cystinuria (n = 1), struvite nephrolithiasis (n = 2), idiopathic hypercalciuria of the absorptive (n = 16), dietary (n = 46) or renal (n = 5) type, and normocalciuric idiopathic urolithiasis (n = 38). Urinary excretion of lysozyme and of gamma-GT were elevated in 14% and 21% of patients respectively; FE glucose and FE insulin were elevated in 6% and 8% of patients respectively. In 62% of the patients TmP/GFR was below 0.95 mmol/l and in 52% of the patients FE HCO3 after alkali load was above normal. The findings show that a large number of stone formers have signs of renal tubular dysfunction; apparent renal leaks of phosphate and of bicarbonate are the most frequently encountered defects; while they are not specific for a given etiologic group of patients, they have been found in each group. The latter observation suggests that nephrolithiasis itself can damage renal tubular function.
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PMID:[Tubular dysfunction in renal lithiasis: cause or consequence?]. 285 24

To address whether a renal tubular dysfunction is encountered in a particular patient subgroup with urolithiasis, the following parameters of tubular function were measured in urine taken in the morning from 214 stone formers after fasting: pH, excretion of lysozyme and gamma-glutamyl transferase (gamma-GT); fractional excretion (FE) of glucose, insulin, Mg, K, and HCO3 after an alkali loading; and the renal threshold for phosphate (TmP/GFR). The following diagnoses were made in the patient group: primary hyperparathyroidism (N = 8), medullary sponge kidneys (N = 21), hyperuricemia (N = 10), cystinuria (N = 2), struvite stone disease (N = 6), idiopathic hypercalciuria of the absorptive (N = 25), dietary (N = 69) or renal (N = 7) type, and normocalciuric idiopathic urolithiasis (N = 66). In 31% of the patients TmP/GFR was below 0.80 mmole/liter and in 13% of the patients, FE HCO3 after alkali loading was above normal. Urinary excretion of lysozyme and that of gamma-GT both were elevated in 17% of the patients. FE glucose, FE insulin, FE Mg, and FE K were elevated in 8, 9, 3, and 7% of the patients, respectively. This study demonstrates that a significant number of stone formers present with signs of renal tubular dysfunction, primarily involving the proximal tubule since apparent leaks of phosphate and of bicarbonate were most frequently encountered. The defects were not specific for a given etiologic group of patients; on the other hand, occurrence was related to the presence of large stones in the pyelocaliceal system at the time data were gathered. Taken together these data suggest that the tubulopathy in nephrolithiasis is the consequence rather than the cause of the stone.
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PMID:Tubulopathy in nephrolithiasis: consequence rather than cause. 287 Dec 16

As a practical contribution to an understanding of the usefulness of measuring some electrolytes in urine, the author first recalls that elements measured in a 24-h urine sample provide nutritional informations, whereas those assayed in fasting morning urine generate data on renal tubular function. To illustrate the first point the author describes assessment of the etiology of hypercalciuria based on a knowledge of concomitant 24-h excretions of sodium, phosphate, urate and creatinine. On the second point, the author suggests dissociating the parameters of which only the urinary concentration is of interest (pH, lysozyme, gamma-glutamyl-transferase) from the parameters of which the excretion--either fractional (Na, K, Cl, P, Mg) or absolute (Ca)--should be calculated. Finally, the reader is reminded how to use the nomogram of Peacock, Robertson and Nordin to evaluate fasting urinary excretion of calcium, and how to use the nomogram of Walton and Bijvoet to estimate the renal threshold phosphate concentration.
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PMID:[Usefulness of urinary electrolyte determination]. 356 52