Calcium salts urinary tract

The high prevalence of oxalate containing renal (tubular) and urinary tract calcifications is related to the low solubility of the oxalate-calcium salt. High urine oxalate excretion increases urine calcium oxalate supersaturation and, therefore the risk of crystal formation in tubular fluid and urine. In human urine, calcium concentration is about ten fold higher than oxalate on molar base. Relatively modest increases in urine oxalate excretion will have significant effects on urine supersaturation [49], especially in patients with hypercalciuria where calcium is even in greater excess of oxalate. Nevertheless, most people do not suffer from renal calcifications [50-54], suggesting that renal protection mechanisms exist. 

When the recommended daily allowance (RDA) for calcium is not met by the diet is (particularly in women), supplementation in the form of calcium salts is recommended. Calcium salts vary widely in calcium content by weight, calcium gluconate has 9%, calcium lactate has 13%, and calcium carbonate has 40% calcium. Absorption of calcium from salts may vary calcium carbonate is the most poorly absorbed. Bone meal and dolomite are not recommended sources of calcium, since they may contain lead, arsenic, mercury, and other toxic metals. A potential complication of excessive calcium intake is formation of urinary tract stones this risk may be reduced by ample fluid intake. 

The normal urinary excretion range of citric acid is 200-1000 mg/day, as has been established by 0stberg (012). The urinary citrate plays a fundamental role in keeping calcium in solution and so preventing the precipitation of calcium salts in the urinary tract (C9, H8, S20). This role is illustrated by the frequency of calcium lithiasis after administration of substances which, lie acetazoleamide (Diamox), reduce the urinary citrate without afifecting the urinary calcium (G16). 

C3H7O4P, Mr 138.06, crystals, mp. 94 °C, [aj -14° (HjO) soluble in water, antibiotic with a wide spectrum of activity produced by streptomycetes and pseudomonads. For the unusual biosynthesis, see Lit.. F. prevents the biosynthesis of bacterial cell walls by inhibiting pyruvate-uridine diphospho-A -acetylglucos-amine transferase (EC 2.5.1.7). The calcium and ammonium salts are used in therapy. F. achieves high urine levels after oral administration and single doses are used for urinary tract infections. 

Kidney stones are solid materials that form in the urinary tract. Most kidney stones are composed of calcium phosphate and calcium oxalate, although they can be solid uric acid. The excessive ingestion of minerals and insufficient water intake can cause the concentration of mineral salts to exceed their solubility and lead to the formation of kidney stones. When a kidney stone passes through the urinary tract, it causes considerable pain and discomfort, necessitating the use of painkillers and surgery. Sometimes ultrasound is used to break up kidney stones. Persons prone to kidney stones are advised to drink six to eight glasses of water every day to prevent saturation levels of minerals in the urine. 

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