A Particular Form of "Urolithiasis" in a Toddler.

Milk of calcium is a viscous colloidal suspension of calcium salts that forms in dilated cysts or cavities. We present, for the first time in literature, a toddler with isolated milk of calcium and treated with a conservative approach. A boy with a history of one urinary tract infection and recurrent fever without vesicoureteral reflux showed at the age of 14 months a left obstructive staghorn stone. Because of absent function of the left kidney at mercapto acetyl tri glycine scintigraphy, a JJ stent was positioned with a leak of whitish material immediately after the stent positioning. Renal scintigraphy performed 1 month later revealed a partial resumption in renal function (18%). When he was 18 months old, the child suffered episodes of acute pain with inconsolable crying, unresponsive to paracetamol administration. Ultrasound assessment revealed left pelvic dilation (anterior-posterior diameter of 18 mm), suspended echogenic debris in the bladder, and dilated left distal ureter with particulate matter. These episodes of acute pain were followed by expulsion of numerous soft formations and emission of greenish urine. Both urine culture at the admission and culture on the greenish urines were sterile. After the expulsion of the soft formations, pain episodes stopped. The diagnosis of milk of calcium stone was made. With this case, we highlight a condition that can be easily diagnosed (if known) because the morphology of the expelled material is pathognomonic. Diagnosing it could avoid unnecessary treatments (ie, extracorporeal shockwave lithotripsy) and support a conservative approach (ie, stent positioning).

Effects of chia (Salvia hispanica L.) on calcium bioavailability and inflammation in Wistar rats.

Chia is a good source of calcium, however it is not been previously reported its bioavailability associated with an inflammatory condition. Thus, the present study evaluated the effect of chia on calcium bioavailability, inflammation, and oxidative stress in Wistar rats fed a high-fat diet or standard diet for 35 days. Chia consumption resulted in lower calcium balance and calcium absorption and retention rates. In addition, the urinary calcium concentration was lower in groups that were fed chia. The bone resistance of animals feed chia was lower than that in rats fed the standard diet receiving calcium carbonate. Animals that were fed chia showed lower total, very low-density lipoprotein, and low-density lipoprotein cholesterol levels than animalsfed calcium carbonate. Animals fed standard diet showed higher superoxide dismutase plasma concentrations than animals in the high fat calcium carbonate group. PPAR-α protein levels were higher in animals fed chia whereas TNF-α and IL-10 were lower in these animals. NFκB mRNA expression and protein levels were lower in the groups that received chia compared with HFD + CC. Chia intake presented low calcium bioavailability regardless of the type of diet consumed and was able to improved inflammation and the lipid profile in young Wistar rat. Besides this, the consumption of this seed increased the activity of antioxidants enzymes.

Calcium supplementation does not augment bone gain in young women consuming diets moderately low in calcium.

In earlier observational work, the dietary calcium:protein ratio was directly related to bone accrual in healthy postadolescent women. In this study, we sought to test the hypothesis that augmented calcium intake would increase postadolescent skeletal consolidation, using a double-blind, randomized, placebo-controlled design. We recruited 152 healthy young women (age 23.1 +/- 2.7 y, BMI 22.5 +/- 3.0 kg/m2); their usual diets, as assessed by 7-d food diaries, were low in calcium (605 +/- 181 mg/d; 15.1 +/- 4.5 mmol/d) and in the calcium:protein ratio (10.1 +/- 2.0 mg/g). The subjects were randomly assigned to supplemental calcium [500 mg calcium (12.5 mmol) as the carbonate, 3 times/d, with meals] or placebo capsules identical in appearance; all participants also took a daily multivitamin, and they were followed for up to 36 mo with bone densitometry (dual energy X-ray absorptiometry; DXA) at 6-mo intervals. A total of 121 subjects remained in the study for at least 12 mo (median time in the study, 35 mo), with a mean compliance level (observed/expected tablet consumption) of 87.7%. DXA data for these 121 subjects indicated modest but significant mean rates of increase (i.e., 0.24 to 1.10%/y) in bone mineral content (BMC; total body, total hip, and lumbar spine) and in lumbar spine bone mineral density (BMD) but no change in total hip BMD. None of these rates of change differed by group, i.e., calcium supplementation did not have any measurable effect on bone mass accrual. By midstudy, the calcium content of the subjects' usual diets for both groups had risen by approximately 15%. The combined effect of improved intakes of dietary calcium and the small amount of calcium added by the multivitamin tablets resulted in a mean calcium intake for the control group > 800 mg (20 mmol)/d, possibly at or near the threshold beyond which additional calcium has no further effect on bone accrual.

Urolithiasis in finishing pigs.

Urolithiasis in sows and neonatal pigs is well-known, but information on its occurrence and impact in finishing pigs is sparse. This study reports three outbreaks of urolithiasis in finishing pigs. In one herd, no symptoms were observed, whereas in the other herds the presence of calculi caused obstruction of the urinary tract resulting in death. Using infra-red spectroscopy, the predominant mineral-type found in the uroliths was calcium carbonate (calcite). Only small amounts of calcium oxalate (< 1%) could be detected. A high urinary pH, small abnormalities in the mineral composition of the feed and insufficient drinking water were the most important risk factors identified. To prevent urolithiasis, it is important to ensure adequate water intake, to provide a balanced mineral diet, and to avoid urinary tract infections.

Effects of calcium carbonate, magnesium oxide and sodium citrate bicarbonate health supplements on the urinary risk factors for kidney stone formation.

We describe a model to illustrate different chemical interactions that can occur in urine following ingestion of individual and combined health supplements. Two types of interactions are defined: synergism and addition. The model was applied to eight healthy males who participated in a study to investigate the chemical interactions between calcium carbonate, magnesium oxide and sodium citrate-bicarbonate health supplements on calcium oxalate urinary stone risk factors. Subjects ingested these components individually and in combination for 7 days. Twenty-four-hour urines were collected at baseline and during the final day of supplementation. These were analysed using standard laboratory techniques. Three different chemical interactions, all involving citrate, were identified: magnesium and citrate exerted a synergistic effect on lowering the relative superaturation (RS) of brushite; the same two components produced a synergistic effect on raising pH; finally, calcium and citrate exerted an additive effect on lowering the RS of uric acid. We propose that the novel approach described in this paper allows for the evaluation of individual, additive and synergistic interactions in the assessment of the efficacy of stone-risk reducing preparations.

Minor constituents of sabulous material in equine urine.

The secondary constituents accompanying calcite and vaterite (crystalline forms of calcium carbonate) in the sabulous deposits from 140 vesical samples and one renal sample of equine urine were studied by infrared spectroscopy (IR), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). Apatitic calcium phosphate, present in 12 per cent of the samples, generally appeared in the form of spherulites with smooth and rough surfaces. Calcium sulphate, clearly detected by IR in 12.7 per cent of the samples, did not have a characteristic structure under SEM, although EDX detected sulphur in the samples. Amorphous silica was observed in one case and had a nodular appearance. Organic fibres were not as common as might have been expected in equine urinary deposits.

Lack of blood pressure effect with calcium and magnesium supplementation in adults with high-normal blood pressure. Results from Phase I of the Trials of Hypertension Prevention (TOHP). Trials of Hypertension Prevention (TOHP) Collaborative Research Group.

Phase I of the Trials of Hypertension Prevention (TOHP) was a randomized, multicenter investigation that included double-blind, placebo-controlled testing of calcium and magnesium supplementation among 698 healthy adults (10.5% blacks and 31% women) aged 30 to 54 years with high-normal diastolic blood pressure (DBP) (80 to 89 mm Hg). Very high compliance (94 to 96% by pill counts) with daily doses of 1 g of calcium (carbonate), 360 mg of magnesium (diglycine), or placebos was corroborated for the active supplements by significant net increases in all urine and serum compliance measures in white men and for urine compliance measures in white women. Overall, neither calcium nor magnesium produced significant changes in blood pressure at 3 and 6 months. Analyses stratified by baseline intakes of calcium, magnesium, sodium, or initial blood pressures also showed no effect of supplementation. These analyses suggested that calcium supplementation may have resulted in a DBP decrease in white women and that response modifiers in this subgroup might have included lower initial urinary calcium levels, urinary sodium levels, or lower body mass index. However, overall analyses indicated that calcium and magnesium supplements are unlikely to lower blood pressure in adults with high-normal DBP. The subgroup analyses, useful to formulate hypotheses, raise the possibility of a benefit to white women, which requires testing in future trials.

Effects of three different calcium preparations on urinary calcium and hydroxyproline excretion in postmenopausal osteoporotic women.

Some authors have claimed that 'solubilized' calcium preparations are better absorbed than calcium carbonate, while others have reported that all forms are equally well absorbed. We measured radiocalcium absorption in 35 postmenopausal osteoporotic women and then gave them on three successive evenings, in random order, three different proprietary calcium preparations (Sandocal containing 1 g of effervescent calcium, Calsup containing 1 g of calcium as the carbonate, and Caltrate containing 1.2 g of calcium as the carbonate). The daily urinary calcium excretion rose significantly and similarly on all three supplements and was greater in the high calcium absorbers than the low calcium absorbers. The fasting urinary hydroxyproline excretion was significantly decreased the morning after administration of each preparation, and one-way analysis of variance showed no significant difference between the days of administration or the type of supplement. The decrease was greater for high absorbers than for low absorbers on all three supplements but the differences did not reach statistical significance. By 36 hours after the last calcium supplement the urinary hydroxyproline had returned to baseline. The response of hydroxyproline excretion (and by implication bone resorption) appears to be rapid in onset and short lived. Strict compliance is therefore important in patients on calcium therapy.

Etiopathogenesis of uncommon canine uroliths. Xanthine, carbonate, drugs, and drug metabolites.

Metabolic disorders, medication, and diagnostic agents may be associated with urolithiasis in dogs. Examples of uroliths that have been uncommonly encountered in dogs include xanthine, dolomite, tetracycline, and sulfonamides. Detection of these and other apparently uncommon uroliths requires a high index of suspicion and proper methods of analysis.

Crystalluria. Observations, interpretations, and misinterpretations.

Crystalluria results from oversaturation of urine with crystallogenic substance. However, oversaturation may occur as a result of in vitro as well as in vivo events. The microscopic appearance of crystals only represents a tentative identification of their composition because variable conditions associated with their formation, growth, and dissolution may alter their appearance. Definitive identification is dependent on physical methods such as optical crystallography, x-ray diffraction, and electron microscopic analysis.

Urinary milk of calcium in children and adults: use of gravity-dependent sonography.

Fifteen cases with urinary milk of calcium (UMC) are presented, all of them secondary to urinary obstruction: ureteropelvic junction stenosis (three cases), staghorn calculus (two), caliceal diverticulum (five), and pyelogenic cyst (five). Four patients (aged 7-19) are the youngest with this affliction reported to date. Milk of calcium proximal to a staghorn calculus has not been described previously. Gravity-dependent sonography was the most efficient and sensitive method of diagnosis. Follow-up of 1-16 years showed the formation and gradual increase in the quantity of UMC without evidence of gross calculus formation within the milk. In two patients, there was spontaneous, partial drainage of UMC.

Urine analysis of three rodent species with emphasis on calcium and magnesium bicarbonate.

The urine composition of three rodent species, mole rat Spalax ehrenbergi, the golden hamster Mesocricetus auratus and the white rat Rattus norvegicus was studied. These three species represent different degrees of fossoriality. The results show that the urine of the species that show a higher degree of fossoriality, the mole rat and the hamster, contain high values of calcium and magnesium bicarbonates when compared with the white rat. From these results it may be assumed that the mole rat as well as the hamster can use the kidney as a pathway for releasing bicarbonate and carbonate. This mechanism may reduce the CO2 concentration in their hypercapnic environment.

Bilateral milk-of-calcium urine and hydronephrosis.

Milk-of-calcium urine associated with hydronephrosis is rare, with only 8 unilateral cases reported previously. We report the first case of bilateral occurrence. Upright films are necessary for making the diagnosis. Although previous reports indicate that the involved kidney has little or no function our patient had only slight impairment of renal function. Nephrectomy should not be done without evaluation of renal function, since some function may be preserved by removing the obstruction that is associated with milk-of-calcium urine and hydronephrosis.

Crystal accumulation and very high short-circuit currents in rabbit urinary bladder.

We describe a condition in rabbits characterized by CaCO3 crystal accumulation and very high short-circuit current (Isc) in the urinary bladder. The incidence of the condition was high in rabbits kept for 2 mo or more in the vivarium. The crystal mass in the bladder increased with age or time until it occupied up to one-third of the bladder volume and occasionally aggregated as stones, and the urine attained a sludgy consistency. In animals with sludgy urine, the urine excreted had a crystal content 20 times lower than that of urine contained in the bladder at time of death, implying retention of crystals in the bladder. Kidney stones were not detected in rabbits with bladder crystals, and bladder crystals were absent in rabbits with kidney stones induced experimentally by uremia. In old rabbits with sludgy urine the Isc, a measure of Na+ transport, was up to 46 microA/cm2 and averaged 12 microA/cm2, seven times the Isc of rabbits with nonsludgy urine. The increased Isc was entirely amiloride sensitive. Noise analysis showed it to arise entirely from increased channel density, without change in single-channel current. With one possible exception, we could not find bacterial infection or abnormalities in plasma aldosterone, GFR, or urinary [Na+], [Ca2+], pH, or osmolality that could explain the condition. The exception is that some unidentified component accounting for half the osmolality of nonsludgy urine is absent or at low concentration in sludgy urine. It remains unknown why the condition develops and whether CaCO3 crystals cause high Isc or vice versa or whether both result from a third factor.

Infrared spectroscopic studies of renal stones.

The chemical composition of 125 urinary stones was determined by means of an infrared spectrophotometric method using the potassium bromide pellet technique. Statistical combinations regarding the chemical composition of the stones are discussed and compared with the findings of other workers. Calcium oxalate was the commonest component of pure as well as mixed stones.

Double-blind study with thiazide in recurrent calcium lithiasis.

The effect of 25 mg. hydrochlorothiazide twice daily on the meta-phylaxis of recurrent calcium lithiasis was compared to placebo in a double-blind study during 1 year in 51 patients. A distinct and continuous decrease in urinary calcium excretion occurred only in patients given hyrochlorothiazide. On the other hand, both groups showed a slight increase in total serum calcium levels, unchanged values for ionized and ultrafilterable calcium, and decreased urinary excretion of oxalate during the study. The activity products of calcium oxalate and calcium phosphate also were decreased in both groups but remained within the metastable range. Spontaneous passage of renal stones occurred during treatment in 6 patients given placebo and in 6 treated with hydrochlorothiazide despite decreased urinary calcium excretion in the latter group. The findings show the specific effect of hydrochlorothiazide treatment to be a decrease in urinary calcium excretion in patients with calcium lithiasis, while other changes appear to be nonspecific effects of treatment.

Implications of the finding of calcium carbonate in rabbit urine with respect to renal acidification.

Formation of calcium carbonate or carbamino compounds in a bicarbonate solution should generate hydrogen ions and thereby elevate the PCO2 of that solution. The presence of these substances in rabbit urine was established by demonstrating a significantly lower value for urine total carbon dioxide content measured by microgasometry (number of moles) than with the titration technique (number of equivalents). As there was a significant correlation between the calcium and the carbonate contents in the urine, we surmised that most of the carbonate was in the form of a suspension of calcium carbonate. Direct analysis of precipitates from rabbit bladders confirmed this impression. The formation of calcium carbonate in a solution should raise the PCO2 by the reaction: Ca2+ + 2HCO3- leads to CaCO3 + H2CO3 with subsequent dehydration of the H2CO3. In vitro studies demonstrated that the addition of 1 mmol calcium to 1 L of a 200 mM bicarbonate solution raised the PCO2 by approximately 50 mmHg (1 mmHg = 133.322 Pa). However, in vivo measurements of the PCO2 of rabbit urine containing a similar quantity of calcium carbonate revealed that there was no such rise in vivo (urine values = blood values). Therefore, the formation of calcium carbonate should have occurred at an earlier site in the nephron, thereby allowing the PCO2 to diffuse into peritubular capillaries during transit through the nephron.