Kiyonori Kataoka

Dietary Intake and Habits Of Japanese Renal Stone Patients

The daily consumption of various nutrients as well as the daily habits of 241 male stone patients were investigated. Hypercalciuric (300 mg. or more per day) calcium stone patients ingested much more total protein, fats, oils and calcium than normocalciuric calcium stone patients, and uric acid stone patients ingested much more total and animal protein, and carbohydrates than calcium stone patients. However, the amount of ingested calcium by the patients (470 mg.) was similar to that of age-matched healthy male subjects (476 mg.) and did not reach the level of the daily nutritive requirements (600 mg.). The patients ingested large amounts of nutrients, especially animal protein, during the evening meal. From these results it was believed that synthetic dietary management, including not only ingesting various amounts of nutrients but also changing dietary habits, is necessary for the prophylaxis of renal stones.

Clinical Effects of Prophylactic Dietary Treatment on Renal Stones

From the investigation of the dietary intake and habits of male Japanese renal stone patients we established several general guidelines. Fluid intake should be increased, especially after dinner. Unbalanced diets should be corrected and avoided (the diet should include different types of food, with vegetables being eaten at every meal and an excessive intake of meat should also be avoided). Three meals a day should be eaten and an excessive intake at dinner should be avoided. The interval from dinner until retiring should be extended. By following these individual dietary guidelines the stone recurrence rate in 199 male calcium stone patients who had received individual dietary instruction decreased remarkably compared to that in male calcium stone patients who had not received individual dietary instruction, not only during the period of outpatient visits but also after outpatient visits were discontinued. From these results we conclude that individual dietary management should be the primary measure for the prophylaxis of renal stone disease in Japan.

Nutritional Risk Factors in Calcium Stone Disease in Japan

The purpose of this study is to examine the nutritional environment affecting calcium stone disease in Japan. The following results were obtained. Renal stone disease in the late 1970s increased by about three times than that of the 1940s . Fats and oils, animal protein and calcium intake increased remarkably after the second World War and milk plus milk products, meat and animal products were increased surprisingly compared with 1950. The most ingested nutrients of calcium stone formers were not much different from the results of the National Nutritive Survey in Japan. But the ingested amount of calcium was unexpectedly small and did not reach the level of the daily nutritional requirement in Japanese (15 mmol). The ingested amount of total protein correlated with urinary calcium excretion and had the highest coefficient of determination to the urinary calcium excretion by multiple regression analysis. We have finished our research of individual dietary habits and suggest that the following individual dietary guidance is the primary treatment for the prophylaxis of renal stone disease.

Epidemiology of urolithiasis in the elderly

To estimate the epidemiology of upper urinary stones in the elderly, a total of 1,957 patients (1,349 men and 608 women) with urolithiasis were studied. The ratio of men to women was approximately 3∶1 in middle-aged (between 30 and 59 years), 1∶1 in young (29 or younger) and 1∶1 in old patients (60 or older). Compared with the age distribution of the entire Japanese population, the incidence of urinary stones was very low in both male and female children, twice as high in middle-aged men, slightly higher in middle-aged women, and equal or slightly lower in the male and female elderly. Stones of calcium oxalate and uric acid occurred more frequently and those of calcium phosphate and struvite less frequently in men than in women. This tendency was especially obvious in the middle-aged. In the old generation, calcium oxalate stones occurred almost equally in men and women. Results of urinary stone analysis were similar among men of the three generations, although the incidence of uric acid stones increased with patient age. In women, however, the incidence of calcium oxalate was higher in the young and old generations, while that of calcium phosphate was higher in the middle-aged.

Magnesium-To-Calcium Ratio in Tap Water, and its Relationship to Geological Features and the Incidence of Calcium-Containing Urinary Stones

We examined the relationship among magnesium and calcium content in tap water, the geological features and urinary stone incidence in Japan. The magnesium-to-calcium ratio in tap water correlated negatively with the incidence of urolithiasis. There was no correlation between calcium and magnesium concentration in tap water and urinary stone incidence. Geological features in Japan were classified into 5 groups. The magnesium-to-calcium ratio in the basalt areas was higher than in the other areas, while ratio in the granite areas was low. In the sedimentary rock areas calcium and magnesium concentrations were high; the magnesium-to-calcium ratio in these areas was between those of the basalt and granite areas. The limestone areas had a much higher calcium concentration. The incidence of urinary stones in the sedimentary rock and basalt areas was lower than that of the granite areas, while that in the limestone areas was the highest. Thus, the incidence of urinary stone is related to the magnesium-to-calcium ratio in tap water and the geological area.

Treatment of vesicoureteral reflux by endoscopic injection of blood.

We have developed a new endoscopic procedure for correction of experimental and clinical reflux. It was technically feasible to correct successfully experimentally produced vesicoureteral reflux in dogs by endoscopic injection of blood. Thirteen ureters (10 patients) with grade I-III vesicoureteral reflux were treated by endoscopic injection of patients heparinized blood behind the ureteral orifice. Before drawing out the needle, small amounts of thrombin and protamine were injected to prevent the leakage of the injected blood. Eight of thirteen treated ureters showed complete absence of reflux. The technique has both advantages and disadvantages. Advantageous points are that it is technically simple and injection can be done a few times when reflux has not disappeared. Furthermore, no complications such as distant migration of injected materials and escape from the bladder mucosa have been observed. A disadvantageous point is that the treatment has not been successful in every case.

Relationship between metabolic acidosis and calcium phosphate urinary stone formation in women.

The relationship between the degree of metabolic acidosis and calcium phosphate stone formation was studied. Furthermore, the reasons why renal tubular acidosis (RTA) and primary hyperparathyroidism (PHPT) dominantly occur in women, and female stone formers more often produce calcium phosphate stone are discussed. Blood was slightly more acidotic in women than in men in both the urolithiasis and the control groups. Likewise, blood was significantly more acidotic and urinary pH significantly higher in patients with PHPT. Patients with RTA had severe metabolic acidosis, and urinary pH was highest among all groups. Calcium phosphate concentration was significantly higher in women than in men, and was also higher in patients with PHPT than in those with urolithiasis. All patients with RTA had pure calcium phosphate stones.The reasons why females are more acidotic and have more calcium phosphate in stones are suspected to be related to progesterone and urinary tract infection.

Calcium oxalate crystal formation in patients with hyperparathyroidism and hyperthyroidism and related metabolic disturbances.

The crystallization of calcium oxalate in the urine of patients with hyperparathyroidism and hyperthyroidism was studied using a mixed suspension mixed product removal (MSMPR) system. In addition, calcium metabolism in hyperthyroidism and its relationship to urolithiasis was investigated. The urines from all the three groups (normal subjects, hyperparathyroid and hyperthyroid patients) showed reduced nucleation rates and increased growth rates in comparison with the control synthetic urine. The nucleation rate was not significantly different between the three human urine groups, while the growth rate was significantly higher in the hyperparathyroid group compared to the normal and hyperthyroid groups. Crystal volume (suspension density) in the hyperparathyroid group was approximately twice that in the other two groups. Serum and ionized calcium levels in hyperparathyroid patients were higher than in normal subjects, while hyperthyroid patients had levels only slightly higher than those in normal subjects. The hyperparathyroid and hyperthyroid groups differed significantly from the normal group in urinary calcium excretion. These two groups also showed significantly higher levels of serum alkaline phosphatase and urinary hydroxyproline than did the normal group. Although hyperthyroid patients have a calcium metabolism similar to hyperparathyroid patients, the incidence of urolithiasis is no different between hyperthyroid and normal subjects. The results of both crystallization and calcium metabolism in hyperparathyroid patients were not significantly different between those with and without urolithiasis. The result of crystallization was also not significantly different between hyperparathyroid patients with and without hypercalciuria. This study suggests that hypercalciuria alone does not produce urinary stones and that urine from hyperparathyroid patients may contain promotors of calcium oxalate crystallization and calcium stone formation.

Determination of urinary oxalate by high-performance liquid chromatography monitoring with an ultraviolet detector

SummaryHigh-performance liquid chromatography (HPLC) monitoring with an ultraviolet detector was carried out to measure urinary oxalate levels in urolithiasis. Interfering substances in urine were removed by anion exchange prior to chromatography. This procedure was found excellent with respect to sensitivity, reproducibility, and analytical recovery. The findings were in agreement with colorimetric date. The mean oxalate level in 24-hour urine was 30.5±15.1 mg in patients with a single episode and 36.3±9.8 mg in recurrent stone formers. The latter values was significantly higher than the normal control level (27.4±3.8 mg).

Inhibitory effect of glutamic acid and aspartic acid on calcium oxalate crystal formation.

The effects of Glu and Asp on calcium stone formation was evaluated in three experiments. Studies using mixed suspension, mixed product removal crystallization and scanning electron microscopy showed that Glu and Asp inhibited the nucleation rate, growth rate and suspension density (crystal mass produced) in proportion to the concentration. The main amino acids in calcium oxalate stones and calcium phosphate stones were Glu and Asp. However, the main amino acids in uric acid stones were glycine and urea, and there were no specific amino acids in struvite stones. The activity of urinary GOT and GPT, which convert Asp and alanine, respectively, to Glu in normal subjects was significantly greater than in calcium stone formation.