Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.5.1.5 (urease)
 7,257 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To compare the frequency of urine infection in calcium oxalate and calcium phosphate stone formers, we reviewed charts from patients whose last renal stone submitted for analysis was predominantly composed of calcium phosphate in 118 and of calcium oxalate in 223. Positive cultures were commoner, but not significantly, in the phosphate than the oxalate stone formers, both in men (17 vs. 7.6%) and women (22 vs. 15%). Bacteria frequently producing urease were found in only 4% of the phosphate group. Urine leucocytes were slightly more frequent in the oxalate group for men and significantly so for women. The results do not support the concept that calcium phosphate stones are mainly due to infection with urease-producing or other bacteria.
Nephron 1990
PMID:Comparison of urinary tract infection in calcium oxalate and calcium phosphate stone formers. 220 21

Struvite stones constitute only about 2-3% of the stones reaching the laboratory for analysis, but the clinical problems they create including sepsis and even renal demise are greater than with any other stone type. This article reviews the evidence that bacterial urease, usually from a Proteus species, is responsible for the chemical changes in urine which result in struvite formation. Available urease inhibitors and other forms of medical management of patients with these stones are discussed. A patient with struvite stones should be assumed to have a progressive disease which cannot be ignored. Even after seemingly successful elimination of stones with lithotripsy and/or percutaneous nephrolithotomy, careful medical follow-up is critical. The medical profession is probably underutilizing postprocedure hemiacidrin irrigation because of shortsighted financial considerations. Primary-care physicians need to be educated in the importance of aggressive management of Proteus and other urea-splitting infections.
Nephron 1999
PMID:Struvite stones. 987 15

Microorganisms may have a role in the pathogenesis and prevention of kidney stones. The subjects of this review include nanobacteria, Oxalobacter formigenes, and lactic acid bacteria. Not reviewed here is the well-described role of infections of the urinary tract with Proteus species and other urease-producing organisms associated with struvite stone formation. Nanobacteria have been proposed to be very small (0.08-0.5 nm), ubiquitous organisms that could play a role in stone formation. The theory is that nanobacteria can nucleate carbonate apatite on their surfaces and thereby provide the nidus for stone formation. However, their existence remains uncertain and many investigators are openly skeptical. Recent investigations suggest that they are artifacts, and not actually living organisms, but their proponents continue to study them. O. formigenes is an obligate anaerobe which may be important in the prevention of stone formation. Its sole substrate for generation of ATP is oxalate. It may thereby metabolize its human host's dietary oxalate and diminish intestinal absorption and subsequent urinary excretion of oxalate. There is evidence that the organism's absence, perhaps sometimes due to courses of antibiotics, may be a cause of hyperoxaluria and stone formation. In early investigations, patients not colonized with the organism can be recolonized. Urinary oxalate can be diminished by accompanying an oxalate-containing meal with the organism. One study demonstrated that a preparation of lactic acid bacteria successfully reduced urinary oxalate excretion in 6 patients with calcium oxalate stones and hyperoxaluria. The mechanism of this effect is uncertain since these bacteria lacked the gene possessed by O. formigenes which codes for that organism's oxalate uptake mechanism. The author is currently completing a small randomized controlled clinical trial with this preparation in calcium stone-forming patients with idiopathic hyperoxaluria.
Nephron Physiol 2004
PMID:Microorganisms and calcium oxalate stone disease. 1549 15