Plasma and Urinary Oxalate and Glycolate in Normal Subjects and Idiopathic Calcium Stone Formers

1994 ◽  
pp. 143-143
Author(s):  
R. A. L. Sutton ◽  
V. R. Walker ◽  
L. Hagen
Author(s):  
J M Brown ◽  
G Stratmann ◽  
D M Cowley ◽  
B M Mottram ◽  
A H Chalmers

Twenty-two recurrent calcium stone formers had 24-h urinary oxalate excretions on their home diets which were significantly greater than those of 30 normal subjects (0·48±0·23 mmol/d; mean±SD compared with 0·31±0·11; P<0·01). The stone formers also demonstrated marked day to day variability in oxalate excretion indicating that a single normal urinary oxalate measurement did not exclude significant hyperoxaluria at other times. On a hospital diet containing 1000 mg calcium per day, urinary oxalate excretion fell significantly from 0·48±0·23 mmol/d to 0·32±0·12; P<0·01. As the urinary calcium excretion in and out of hospital was similar, it seems unlikely that low calcium intake at home was responsible for the hyperoxaluria. All patients had recurrent symptomatic stone disease and had been advised to avoid foods rich in oxalate. Whilst poor compliance is a possible explanation for the variability in oxalate excretion, we believe it is more likely that there is an inadvertent intake of oxalogenic precursors in their diet. As normal subjects do not demonstrate hyperoxaluria on similar home diets, stone formers may have a metabolic defect in the handling of these precursors.


1987 ◽  
Vol 33 (2) ◽  
pp. 243-247 ◽  
Author(s):  
D M Cowley ◽  
B C McWhinney ◽  
J M Brown ◽  
A H Chalmers

Abstract An investigation of variables important to calcium stone formation in urine indicated significantly increased daily excretion of calcium and oxalate and decreased excretion of ascorbate and citrate by recurrent calcium stone formers. In addition, urine volume, sodium, mucopolysaccharide, and protein were also significantly increased. We compared the uptake of citrate and ascorbate from the gut into the blood in normal controls and stone formers. These studies indicated significantly depressed absorption of both these hydroxycarboxylic acids in recurrent calcium stone formers. We also found that concurrent administration of citrate inhibited ascorbate absorption and increased urinary oxalate excretion after an ascorbate load in normal subjects and stone formers. These findings suggest a mechanism that explains hyperoxaluria in stone patients on the basis of a malabsorption of citrate, ascorbate, and possibly other hydroxycarboxylic acids.


1986 ◽  
Vol 32 (2) ◽  
pp. 333-336 ◽  
Author(s):  
A H Chalmers ◽  
D M Cowley ◽  
J M Brown

Abstract Studies of recurrent stone formers indicated that they have significantly increased urinary oxalate and decreased ascorbate excretions. Results of oral and intravenous administration of ascorbate indicate an enhanced production of oxalate from ascorbate in recurrent calcium stone formers as compared with normal persons and that most of this oxalate is generated in the gut.


1984 ◽  
Vol 66 (2) ◽  
pp. 193-199 ◽  
Author(s):  
V. R. Walker ◽  
R. A. L. Sutton

1. Idiopathic calcium stone-formers with hypercalciuria during fasting have significantly lower urinary cyclic AMP levels (nmol/dl of glomerular filtrate) than fasting normocalciuric stone-formers. 2. Female subjects, including both normal subjects and idiopathic calcium stone-formers, have higher urinary cyclic AMP levels than their male counterparts, and this difference is significant when urinary cyclic AMP is expressed in the units μmol/g of creatinine. Expressing urinary cyclic AMP in nmol/dl of glomerular filtrate reduces this difference but does not abolish it. Thus, in comparing urinary cyclic AMP levels in various subgroups of the calcium stone-formers and in normal subjects, both sex differences and the units of urinary cyclic AMP expression must be taken into consideration. 3. The magnitude of the change in urinary cyclic AMP in response to an oral calcium load appears to depend on the antecedent urinary cyclic AMP excretion rate, whereby those individuals (either normal subjects or calcium stone-formers) having the highest urinary cyclic AMP levels demonstrate the greatest fall in urinary cyclic AMP after a calcium load.


1979 ◽  
Vol 65 (3) ◽  
pp. 143-146
Author(s):  
M. A. Macleod ◽  
N. J. Blacklock

AbstractWith evidence of induction of increased urinary excretion of calcium by the ingestion of glucose and sucrose there is the theoretical possibility in these circumstances of at least a transient negative calcium balance. In this study the ingestion of glucose or glucose equivalent was found to stimulate 47Ca absorption from the intestine both in normal subjects and in idiopathic calcium stone formers. This induced increase in the rate of 47Ca absorption by glucose can be negated by the addition of crude fibre in the form of wheat bran.


Sign in / Sign up

Export Citation Format

Share Document