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Query: UMLS:C0451641 (urolithiasis)
 3,973 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It is generally accepted that acromegaly is often associated with hypercalciuria, but there are few reports on the frequency and the mechanisms of urolithiasis. Recently we consecutively experienced 2 cases of acromegaly with urolithiasis, and these experiences made us investigate the association between urolithiasis and acromegaly. Among 18 acromegalies from 1977 to March 1990 (10 males, 8 females, 24-64 years old), 13 cases (72%) fulfilled the criteria of hypercalciuria (urinary calcium (u-Ca) greater than or equal to 200 mg/day or u-Ca/urinary creatinine (u-Ca/u-Cr) greater than or equal to 0.15), and 7 cases (39%) suffered from urolithiasis that was diagnosed by KUB (4 cases) or X-ray computed tomography (CT) (3 cases). Especially in the last 2 years, 5 out of 7 cases (71%) were complicated with urolithiasis and all 7 cases were associated with hypercalciuria. These results suggest that hypercalciuria and urolithiasis are both much more frequent than previously reported. In 6 cases who were treated by pituitary adenomectomy from 1988-1989 (4 males, 2 females, 24-59 years old), we examined Ca metabolism before and after operation. Before operation, the levels of serum growth hormone (GH), u-Ca (mg/day), u-Ca/u-Cr (in all cases) and plasma somatomedin-C (Sm-C) (in 4 cases) were increased above the normal range. To determine the etiology of hypercalciuria, we performed the oral Ca load test under restriction of Ca (400 mg/day) and P (650 mg/day) intake. The results suggested that the hypercalciuria might be mainly due to the increased absorption of Ca from the intestine (so-called "Absorptive hypercalciuria"). However, the levels of serum vitamin D (Vit. D) metabolites were all within the normal range before operation. After operation, GH and u-Ca/u-Cr (in 5 cases) and u-Ca (mg/day) (in all cases) decreased significantly compared with before operation, and the levels of Sm-C (in all cases), serum 25-(OH)D3, 1 alpha, 25-(OH)2D3 (in 4 cases) and 24,25-(OH)2D3 (in 3 cases) were also reduced after operation. Surprisingly, u-Ca and u-Ca/u-Cr normalized only in 4 cases who showed a reduction in 1 alpha, 25-(OH)2D3 levels after operation, although there were no correlations between u-Ca (mg/day) or u-Ca/u-Cr and 1 alpha, 25-(OH)2D3. Significant correlations were found between u-Ca (mg/day) or u-Ca/u-Cr and Sm-C. The parathyroid function evaluated by the rapid Ca infusion test or nephrogenous cyclic adenosine monophosphate (NcAMP) was normal before and after operation.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[The frequency and mechanisms of urolithiasis in acromegaly]. 188 13

Urinary lithogenic promoters and inhibitors were estimated in normal Indian men and women of young and old ages to understand the sex difference in the risk of stone disease. Young men displayed increased phosphate excretion and a higher mean calcium (both lithogenic promoters) and lower excretion of citrate (lithogenic inhibitor) compared to women of the same age indicating that young men are more at risk for calculous disease than women. In the older postmenopausal women, there was increased excretion of calcium and magnesium and a lower mean citrate than in the younger women suggesting that oestrogenic activity during reproductive years appears to offer protection against calculogenesis. This study indicates that sex differences exist in the excretion of lithogenic promoters and inhibitors which partly explain the difference in the incidence of urolithiasis between men and women.
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PMID:Influence of sex and age in the risk of urolithiasis--a biochemical evaluation in Indian subjects. 189 47

Hypercalciuria (HCU) is frequently found during the evaluation of children with hematuria; the long-term implications of untreated HCU in children are uncertain. Since 1981, we have identified HCU (urinary calcium, greater than 0.1 mmol.kg-1.d-1) in 58 patients (41 male) with hematuria; 64% had gross hematuria and 74% had a relative with urolithiasis. Renal HCU was diagnosed in 19 patients and absorptive HCU in 24 patients. In 15 children, the calcium loading test was nondiagnostic. In nine patients (16%), urolithiasis developed, and in one patient, a renal calcification developed. These 10 patients (seven male) were older (10.1 vs 7.5 years) than the other 48 patients and initially presented with gross hematuria (nine of 10). All 10 patients had a family history of urolithiasis. The initial urinary calcium value was similar between the 10 patients with stones (0.15 mmol.kg-1.d-1) and the patients without stones (0.14 mmol.kg-1.d-1); five had absorptive HCU and four had renal HCU. At least one follow-up urinary calcium measurement was available for 23 patients who were not receiving thiazide therapy during 1 to 6 years after diagnosis (mean, 3.1 years). At 1-year follow-up, 12 of 17 patients had HCU and five had hematuria. Twenty-one patients were studied 2 to 3 years from diagnosis; 11 had HCU and eight had hematuria. After 4 years, six of seven patients had HCU and three had hematuria. We concluded that children with HCU and hematuria are at significant risk for urolithiasis, especially if they have gross hematuria and a family history of urolithiasis. Hypercalciuria may be episodic in children with hematuria, and factors other than urinary calcium concentration may be responsible for urinary bleeding.
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PMID:Natural history of hematuria associated with hypercalciuria in children. 192 18

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.
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PMID:Relationship between metabolic acidosis and calcium phosphate urinary stone formation in women. 193 25

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.
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PMID:Epidemiology of urolithiasis in the elderly. 193 39

About 7% of patients with calcium urolithiasis suffer from primary hyperparathyroidism. A systematic search for this diagnosis is therefore mandatory in such patients. Because hypercalcemia is often discrete or intermittent, determinations of calcium levels should be repeated at least thrice. Measurement of ionized calcium levels improves the detection of hypercalcemia. The biological diagnosis is based on the presence of hypercalcemia together with an increased plasma level of 1-84 intact parathormone (PTH). A PTH value still in the normal range but inappropriately elevated in the context of hypercalcemia could be sufficient for the diagnosis of primary hyperparathyroidism.
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PMID:[Should the parathyroid function be evaluated in a patient with calcium kidney stones? If so, when and why?]. 194 59

Almost all segments of the gastrointestinal tract have been used as urinary tract substitutes. The specific nutritional and gastrointestinal complications depend on the particular portion of bowel that is removed from the alimentary tract. The use of stomach theoretically may predispose the patient to hypergastrinemia and peptic ulcer disease, hypocalcemia, and iron deficiency or megaloblastic anemia. Resection of a large amount of jejunum causes malabsorption. Limited use of colon segments usually is well tolerated, but loss of large parts of the colon directly decreases available absorptive area, resulting in diarrhea. Resection of the ileum and ileocecal valve can lead to several disease states. One is mixed secretory-osmotic diarrhea. Decreased ileal reabsorption of bile salts results in fat malabsorption and steatorrhea. The presentation of increased amounts of bile salts and fatty acids to the colon decreases water absorption and stimulates active chloride and water secretion, producing a cholera-like high-volume secretory diarrhea. The loss of the ileocecal valve and ileum segment accelerates intestinal transit time, which does not allow for complete digestion and absorption of food. Water and electrolytes remain associated with undigested food particles and may overwhelm the absorptive capacity of the colon, resulting in an osmotic diarrhea. A second problem is vitamin B12 deficiency. Surgical reduction of sites in the terminal ileum for active and exclusive uptake of vitamin B12 might lead to hypovitaminosis. If this is unrecognized, patients may develop irreversible neurologic injury. A third problem is cholelithiasis. Derangements in bile salt metabolism can occur when as little as 10 cm of ileum is resected, and the propensity to form gallstones is increased. Pigment gallstones appear to be the predominant stone associated with ileal resections. The fourth possible problem is urolithiasis, the etiology of which is multifactorial in patients with ileal resections. With decreased availability of bile salts, fat malabsorption occurs. Fatty acids bind with calcium and magnesium to form soaps, resulting in increased levels of free oxalate available for absorption. Moreover, fatty acids directly increase colonic permeability to oxalate.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Nutritional and gastrointestinal complications of the use of bowel segments in the lower urinary tract. 194 6

The nutritional management of individuals with recurrent calcium urolithiasis requires an individualized approach to the establishment of long-term goals. Diet therapy should be instituted only after careful consideration of serial metabolic evaluation of blood and urine parameters, along with stone analysis data. Interval monitoring of patient progress provides an opportunity for the identification and correction of clinical problems associated with the establishment of long-term goals.
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PMID:Nutritional management of patients with kidney stones. 195 13

We have studied the metabolic response to changes in calcium in 15 hypercalciuric essential hypertensives, in 8 normotensive hypercalciuric stone formers and in 11 normotensive healthy subjects matched for age and sex. At variance with hypercalciuric stone formers, at low calcium intake hypercalciuric hypertensives did not appropriately reduce urinary calcium excretion and developed mild hypocalcemia. Furthermore, the PTH response to calcium deprivation was not appropriately enhanced in these patients. The data indicate that different mechanisms prevail in these two forms of hypercalciuria: the renal in essential hypertension and the intestinal in urolithiasis.
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PMID:Mechanism of hypercalciuria in essential hypertension and in primary nephrolithiasis. 195 54

After detailed instruction, 62 patients with urolithiasis treated at Taichung Veterans General Hospital entered this program, which ran from September 1987 to November 1988. Based on Pak's classification, there were 13 cases (21.0%) of absorptive hypercalciuria, type I (AH-I); 12 cases (19.4%) of absorptive hypercalciuria, type II (AH-II); 16 cases (25.8%) of renal hypercalciuria (RH); 3 cases (4.8%) of hyperuricosuric calcium urolithiasis (HUCU); 11 cases (17.7%) of hypocitraturia (Hypocit); 3 cases (4.8%) of hyperoxluria (HO); one case (1.6%) of primary hyperparathyroidism (PHPT) and one case (1.6%) of infectious lithiasis. Two cases (3.2%) with no metabolic abnormalities were found. Hypocitraturia, HUCU, and HO can be the primary abnormal findings, but more often coexist with various forms of hypercalciuria as a second factor. If the coexistence is considered, hypocitraturia (33 cases, 53.2%) and HUCU (24 cases, 38.7%) were the most prevalent categories. Meanwhile, 24 cases (38.7%) had only one physiological derangement, 25 cases (40.3%) had two derangements, and 13 cases (21.0%) had three. This study indicates that metabolic evaluation can elucidate the physiological derangements of urolithiasis, so that further medical treatment can be administered selectively.
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PMID:Metabolic evaluation of urolithiasis. 197


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