Serum and urinary zinc levels in urolithiasis

Zinc has an important place amongst inhibitors of crystallisation and crystal growth. These views are supported by in vivo and in vitro studies which suggest that the urinary zinc level is a significant factor in urolithiasis. Some recent studies have given contradictory results. Blood serum and urinary zinc levels were measured in 30 normal healthy controls and 42 stone forming patients (renal, ureteric and vesical). Statistically significant levels were found in all groups, varying according to the number of calculi. Increased urinary zinc levels and decreased serum zinc levels appear to be secondary to the process of stone formation. The role of zinc as an inhibitor of urolithiasis is questionable.     

Inhibitors of calcium oxalate crystallization and urolithiasis

In urolithogenic processes both, promoters and deficit of inhibitors, play an important role. The inhibitory action of added inhibitors (magnesium, citrate, pyrophosphate and chondroitin sulphate) was investigated using the urine of 72 patients with calcium urolithiasis. It was concluded that the deficit of inhibitors seems to be an important cause of stone formation in idiopathic oxalocalcic urolithiasis. Nevertheless, when that specific heterogeneous nucleation takes place it becomes an important factor and the inhibitor plays a complementary role in calcium oxalate urolithiasis.     

Xanthine urolithiasis in a dachshund

Calculi were located in the kidneys, the ureters and the bladder of a two-year-old male dachshund. The yellow-greenish calculi developed as a result of impaired transformation of xanthine to uric acid resulting in an increased concentration of xanthine in the urine. The cause of the impaired catabolism of xanthine was probably a disorder of the xanthine oxidase enzyme, which catalyses the transformation of xanthine to uric acid.     

Idiopathic calcium oxalate urolithiasis and endogenous oxalate production

Despite the great effort that has gone into investigating urolithiasis, this condition still persists as one of the major ailments of the urinary tract. Calcium oxalate urolithiasis is the most common form, accounting for some 60 to 80% of total stones. This review examines the elements (i.e., urine volume and pH and urinary excretion of calcium, oxalate, citrate, urate, magnesium, pyrophosphate, and glycosaminoglycans) that give rise to idiopathic calcium oxalate urolithiasis. Treatment strategies for idiopathic calcium oxalate urolithiasis, including lithotripsy, also are discussed. Urinary oxalate excretion is a major risk factor for calcium oxalate urolithiasis, with 85 to 95% of the urinary load derived endogenously. The factors controlling endogenous oxalate production are reviewed, including pathways for the diversion of glyoxylate from oxalate production. The use of beta-aminothiols and other substances to reduce endogenous oxalate production in subjects with idiopathic calcium oxalate urolithiasis is also discussed. A review of current methodologies for the determination of urinary oxalate is also included.     

Surgical treatment of urolithiasis in Norway

The aim of the study was to investigate treatment strategies for urolithiasis as they are practised in Norway today. A questionnaire was sent to the somatic hospitals in Norway. All surgical treatment of urolithiasis was to be registered over a three month period, from 1 September to 30 November 1992. 78% of the hospitals responded, and 505 patients were included in the survey. Extracorporeal shock wave lithotripsy, percutaneous nephrolithotomy and uretero-renoscopy are well established treatment modalities in all parts of the country. The treatment practice follows the accepted international guidelines and treated at the larger treatment centres.     

Incidence of urolithiasis in northeast Thailand

We performed an anterior spinal fusion using a vascularized fibular bone graft combined with posterior fusion for a patient with severe cervical kyphosis due to neurofibromatosis. The kyphosis was corrected from 85 degrees preoperatively to 38 degrees postoperatively. A vascularized fibular bone graft is a useful surgical procedure in selected patients to obtain successful bony union.     

Urinary urease activity in urolithiasis patients

The professional body for State Registered Dietitians, the British Dietetic Association (BDA), has been instructed by the NHS Executive Clinical Audit Unit to produce and validate national dietetic standards across all clinical specialties. The BDA have so far produced eight National Professional Standards (Table 1) that can be used as a framework for developing local standards.     

Etiological and clinical patterns of urolithiasis in Turkish children

A beta-glucan binding protein (BGBP) was identified in both white (Penaeus vannamei) and blue shrimp (P. stylirostris) plasma. White shrimp BGBP was purified by affinity chromatography using immobilized laminarin, and its molecular and biological properties were described. White shrimp BGBP is a monomeric protein with a molecular mass of 100 kDa, similar to those described for other crustacean BGBPs. White and blue shrimp BGBPs can be detected with antisera against crayfish BGBP and brown shrimp BGBP. Both amino acid composition and N-terminal sequence are markedly similar to brown shrimp (P. californiensis) and crayfish (Pacifastacus leniusculus) BGBP, indicating that this recognition protein is present in freshwater and marine crustaceans.     

Incidence and clinical features of renal tubular acidosis-1 in urolithiasis

A simple, selective, reversed phase liquid chromatographic method using a column-switching technique has been developed for the simultaneous determination of a novel derivative of etoposide (NK611) and its O-demethyl metabolite in dog plasma. A good linear response was obtained for both drugs in the range 0.1-12.0 micrograms/mL. The mean recoveries were within 100 +/- 5%. The within- and between-day precisions were within 3.5% and 4.6%, respectively. This method was used in a pharmacokinetic study following intravenous and oral administration of NK611 to beagle dogs.     

Association between hyperadrenocorticism and development of calcium-containing uroliths in dogs with urolithiasis

OBJECTIVE: To determine, among dogs with urolithiasis, whether dogs that had hyperadrenocorticism would be more likely to have calcium-containing uroliths than would dogs that did not have clinical evidence of hyperadrenocorticism. DESIGN: Retrospective case-control study. ANIMALS: 20 dogs that had urolithiasis and hyperadrenocorticism and 42 breed-matched dogs that had urolithiasis but did not have clinical evidence of hyper-adrenocorticism. PROCEDURE: Signalment, urolith composition, results of bacterial culture of urine, and results of adrenal axis tests were recorded. A multivariate logistic regression model was created, including terms for age, sex, and hyperadrenocorticism. The outcome variable was presence or absence of calcium-containing uroliths. RESULTS: Among dogs with urolithiasis, those that had hyperadrenocorticism were 10 times as likely to have calcium-containing uroliths as were dogs that did not have clinical evidence of hyperadrenocorticism (odds ratio, 10.5; 95% confidence interval, 1.5 to 23.4). Neutered and sexually intact females were less likely to have calcium-containing uroliths than were neutered males (odds ratios, 0.041 [95% confidence interval, 0.0057 to 0.29] and 0.024 [95% confidence interval, 0.0012 to 0.51, respectively). CLINICAL IMPLICATIONS: Prompt diagnosis and treatment of hyperadrenocorticism may decrease prevalence of calcium-containing uroliths in dogs.     

Enhanced renal vitamin-K-dependent gamma-glutamyl carboxylase activity in experimental rat urolithiasis

OBJECTIVE: To investigate the role of glycemic control and blood pressure in the development and progression of nephropathy and to suggest goals for glycemic control and blood pressure for the prevention of nephropathy in elderly Japanese NIDDM patients. RESEARCH DESIGN AND METHODS: A total of 123 age- and diabetes duration-matched elderly Japanese NIDDM patients (aged 60-75 years; 74 normoalbuminuric and 49 microalbuminuric) were retrospectively studied for 6 years. RESULTS: The group that developed microalbuminuria from normoalbuminuria (group NM: n = 24) showed a higher 6-year mean HbA1c than the group that remained normoalbuminuric (group NN: n = 50; 9.0 +/- 0.8 vs. 8.1 +/- 0.8%, P < 0.01) in spite of no significant difference in 6-year mean blood pressure (MBP). On the other hand, the group that progressed from microalbuminuria to overt proteinuria (group MP: n = 26) showed a higher 6-year MBP than the group that remained microalbuminuric (group MM: n = 23; 106 +/- 5 vs. 95 +/- 6 mmHg, P < 0.01) in spite of no significant difference in 6-year mean HbA1c. The cutoff level of HbA1c separating group NN from group NM was 8.5% (normal range < or = 6.5%), and that of MBP separating group MM from group MP was 100 mmHg. CONCLUSIONS: Glycemic control is a more potent factor than blood pressure level on the development of microalbuminuria. However, as far as the progression of microalbuminuria to overt proteinuria is concerned, hypertension is the most crucial factor in elderly NIDDM patients. Suggested goals for glycemic control and blood pressure level for the prevention of nephropathy in elderly Japanese patients are an HbA1c of < or = 8.5% (equivalent to 7.8% in the current measurement of stable HbA1c; normal range < or = 5.8%) and an MBP of < or = 100 mmHg.     

Variants of dysfunction of the upper urinary tract in urolithiasis

Registration of contractility of the upper urinary tracts (UUT) at multichannel impedance ureterography was conducted in 30 patients with concrements in the kidneys and ureters before extracorporeal lithotripsy. By defects in urodynamics, the patients were divided into 4 groups. The most severe affection of urodynamics (low amplitude of the peristalsis, high tonicity of UUT wall) occurred in group 4. From group 1 to 4 contraction arrhythmia, deformity of contraction complexes, retrograde contraction waves were increasing. The index has been calculated for estimation of UUT performance in transporting urine.     

Symptomatology and development of urolithiasis in children with frequency-dysuria syndrome associated with hypercalciuria

Transduction of mitogenic signals in cells can be mediated by molecules derived from the synthesis and breakdown of the major membrane phospholipid, phosphotidylcholine. Studies were performed on human mammary epithelial cells in culture to understand the impact of malignant transformation and progression on membrane phospholipid metabolism. In the model system used here, phosphocholine levels and total choline-containing phospholipid metabolite levels increased with progression from normal to immortalized to oncogene-transformed to tumor-derived cells. These changes occurred independently of cell doubling time. A "glycerophosphocholine to phosphocholine switch" was apparent with immortalization. This alteration in phenotype of increased phosphocholine relative to glycerophosphocholine was observed in oncogene-transformed and for all human breast tumor cell lines analyzed. The results demonstrate that progression of human mammary epithelial cells from normal to malignant phenotype is associated with altered membrane choline phospholipid metabolism.     

Pulsed dye laser lithotripsy for treatment of urolithiasis in two geldings

Transendoscopic pulsed dye laser lithotripsy was effective in the treatment of calcium carbonate urothlithiasis in 2 adult geldings. Perineal urethrotomy provided convenient access for standing transendoscopic lithotripsy and evacuation of a large cystic calculus in one gelding. In the second horse, an obstructive urethral calculus was fragmented and removed by a transurethroscopic approach. Pulsed dye laser lithotriptor is effective in fragmentation of the most common form (calcium carbonate) of uroliths in horses and may be performed in standing horses with reduced surgical invasiveness and trauma to the urinary tract, compared with conventional approaches. The principle disadvantages include cost of the procedure, which is comparable to laparocystotomy, and the time delay required to make arrangements for use of the pulsed dye laser lithotriptor.