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

Urolithiasis is a disease with complex and not fully explained etiology and pathogenesis. In its development there play role multiple factors, such as individual features of the kidneys and urinary tract, co-existing infections with urease-producing pathogens and environmental factors. Advance in the field of organ imaging has enabled development of new harmless diagnostic procedures that allowed for fast diagnosis, and current methods of treatment (USR, PCNL and ESWL) have significantly limited the number of surgical procedures performed because of urolithiasis. Introduction of these treatment methods markedly disturbed used for a long time scheme of management and in many cases it limited invasiveness of the treatment and shortened hospitalisation time. Unfortunately, not all urology departments in Poland have access to the newest methods of treatment, thus a percentage of patients treated with traditional methods is still high. Used nowadays methods of diagnosis and treatment have not fully solved a problem of urolithiasis metaphylaxis, and urolithiasis still remains a serious disease that requests close cooperation of the patients, nephrologist and urologist.
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PMID:[Diagnosis, prophylaxis and treatment of urolithiasis]. 938 Aug 9

Recurrent formation of renal calculi may be prevented by selective medical therapy designed to correct underlying metabolic disturbances in urine biochemistry. The aim of the study was to estimate potential risk factors of urolithiasis in 102 children before ESWL treatment. Metabolic disturbances followed by anatomical malformations of urinary tract, recurrent urinary tract infections caused by urease-induced microorganisms are the most frequent risk factors. In single cases possible risk factors were: immobilization and chronic corticosteroid therapy.
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PMID:[Etiology of nephrolithiasis in children: own observation]. 1089 98

Concentrations of Na, K, Ca ions, oxalic and uric acids, total Ca, P as well as urease activity, the ability to form crystals, speed of crystallization, crystal chemical composition, pH stability were evaluated in the urine from 40 urolithiasis patients and 40 patients with recurrent nephroliths. It was found that fast or moderate crystallization, high urease activity and ability to form crystals, unstable urine pH indicate a high risk of both primary and recurrent nephrolith formation.
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PMID:[Laboratory methods of predicting primary and recurrent nephrolithiasis]. 1139 29

The virulence of a urease-negative mutant of uropathogenic Proteus mirabilis and its wild-type parent strain was assessed by using a CBA mouse model of catheterized urinary tract infection. Overall, catheterized mice were significantly more susceptible than uncatheterized mice to infection by wild-type P. mirabilis. At a high inoculum, the urease-negative mutant successfully colonized bladders of catheterized mice but did not cause urolithiasis and was still severely attenuated in its ability to ascend to kidneys. Using confocal laser scanning microscopy and scanning electron microscopy, we demonstrated the presence of P. mirabilis within the urease-induced stone matrix. Alizarin red S staining was used to detect calcium-containing deposits in bladder and kidney tissues of P. mirabilis-infected mice.
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PMID:Visualization of Proteus mirabilis within the matrix of urease-induced bladder stones during experimental urinary tract infection. 1174 5

Proteus mirabilis is a documented cause of urinary tract infection (UTI) in the complicated urinary tract. Urease-mediated urea hydrolysis is responsible for both virulence of the organism and the ability to cause urolithiasis. A urease-negative mutant of P. mirabilis is unable to initiate stone formation and colonizes the kidney at a significantly lower rate. The considerable pathology caused by P. mirabilis warrants the development of a vaccine. We have initiated the advancement of vaccine studies and have determined that the MR/P fimbria, a surface adhesin of P. mirabilis, is a promising vaccine candidate. Successful vaccination would be expected both to prevent colonization by P. mirabilis and urolithiasis.
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PMID:Vaccines for Proteus mirabilis in urinary tract infection. 1213 33

Urease-producing bacteria have been shown to affect the formation of infection stones by splitting urea into ammonia, bicarbonate and carbonate. An increase in alkaline pH results in urinary supersaturation of the ions. The increase in ammonia also causes injury to the urothelial glycosaminoglycan layer. Non-urease-producing bacteria have been speculated to form urinary stones. Midstream voided bladder urine and fractured stone nidus samples from 72 patients undergoing surgery for urolithiasis were cultured on specific media for genital mycoplasmata and on conventional media. Urine samples were obtained from a control group of 40 healthy subjects. Genital mycoplasmata and other bacteria were evaluated with regard to the composition of urinary stones. Compared with other origins of stones, the relation between isolation of Ureaplasma urealyticum and infection stone disease was statistically proven. Isolation of genital mycoplasmata was significantly higher in women than in men in the study group. The urinary stones comprised 84.7% calcium stones, 8.3% uric acid stones and 6.9% infection (magnesium ammonium phosphate) stones. Coagulase-negative Staphylococci, Escherichia coli, Corynebacterium spp., Enterobacterium spp. and U. urealyticum were cultured from stone samples. The results suggests that non-urease-producing bacteria, as well as urease-producing bacteria, may influence the formation of urinary stones.
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PMID:Role of genital mycoplasmata and other bacteria in urolithiasis. 1287 17

Proteus mirabilis commonly infects the complicated urinary tract and is associated with urolithiasis. Stone formation is caused by bacterial urease, which hydrolyzes urea to ammonia, causing local pH to rise, and leads to the subsequent precipitation of magnesium ammonium phosphate (struvite) and calcium phosphate (apatite) crystals. To prevent these infections, we vaccinated CBA mice with formalin-killed bacteria or purified mannose-resistant, Proteus-like (MR/P) fimbriae, a surface antigen expressed by P. mirabilis during experimental urinary tract infection, via four routes of immunization: subcutaneous, intranasal, transurethral, and oral. We assessed the efficacy of vaccination using the CBA mouse model of ascending urinary tract infection. Subcutaneous or intranasal immunization with formalin-killed bacteria and intranasal or transurethral immunization with purified MR/P fimbriae significantly protected CBA mice from ascending urinary tract infection by P. mirabilis (P < 0.05). To investigate the potential of MrpH, the MR/P fimbrial tip adhesin, as a vaccine, the mature MrpH peptide (residues 23 to 275, excluding the signal peptide), and the N-terminal receptor-binding domain of MrpH (residues 23 to 157) were overexpressed as C-terminal fusions to maltose-binding protein (MBP) and purified on amylose resins. Intranasal immunization of CBA mice with MBP-MrpH (residues 23 to 157) conferred effective protection against urinary tract infection by P. mirabilis (P < 0.002).
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PMID:Development of an intranasal vaccine to prevent urinary tract infection by Proteus mirabilis. 1468 82

Massive urolithiasis of the penile urethra was observed in an adult pygmy sperm whale (Kogia breviceps) stranded on Topsail Island, North Carolina, USA. Calculi occupied the urethra from just distal to the sigmoid flexure to the tip of the penis for a length of 43 cm. A urethral diverticulum was present proximal to the calculi. The major portion of the multinodular urolith weighed 208 g and was 16 cm long x 3.7 cm diameter at the widest point. The urolith was composed of 100% struvite (magnesium ammonium phosphate) and on culture yielded Klebsiella oxytoca, a urease-positive bacterium occasionally associated with struvite urolith formation in domestic animals. Reaction to the calculi was characterized histologically by moderate multifocal to coalescing plasmacytic balanitis and penile urethritis. Role of the urethrolithiasis in the whale's stranding is speculative but could have involved pain or metabolic perturbations such as uremia or hyperammonemia.
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PMID:Struvite penile urethrolithiasis in a pygmy sperm whale (Kogia breviceps). 1546 32

Although urolithiasis is common in spinal cord injury patients, it is presumed that the predisposing factors for urinary stones in spinal cord injury patients are immobilization-induced hypercalciuria in the initial period after spinal injury and, in later stages, urine infection by urease-producing micro-organisms, e.g., Proteus sp., which cause struvite stones. We describe a patient who sustained C-7 complete tetraplegia in a road traffic accident in 1970, when he was 16 years old. Left ureterolithotomy was performed in 1971 followed by left nephrectomy in 1972. Probably due to adhesions, this patient developed volvulus of the intestine in 1974. As he had complete tetraplegia, he did not feel pain in the abdomen and there was a delay in the diagnosis of volvulus, which led to ischemia of a large segment of the small bowel. All but 1 ft of jejunum and 1 ft of ileum were resected leaving the large bowel intact. In 1998, suprapubic cystostomy was performed. In 2004, this patient developed calculus in the solitary right kidney. Complete stone clearance was achieved by extracorporeal shock wave lithotripsy. Stone analysis: calcium oxalate 60% and calcium phosphate 40%. Metabolic evaluation revealed hyperoxaluria, hypocitraturia, and hypomagnesiuria. Since this patient had hyperoxaluria, the stool was tested for Oxalobacter formigenes, a specific oxalate-degrading, anerobic bacterium inhabiting the gastrointestinal tracts of humans; absence of this bacterium appears to be a risk factor for development of hyperoxaluria and, subsequently, calcium oxalate kidney stone disease. DNA from the stool was extracted using the QIAamp DNA stool Mini Kit (Qiagen, Chatsworth, CA). The genomic DNA was amplified by polymerase chain reaction using specific primers for oxc gene (developed by Sidhu and associates). The stool sample tested negative for O. formigenes. The patient was prescribed potassium citrate mixture; he was advised to avoid oxalate-rich food, maintain recommended levels of calcium in his diet, and take live bio-yogurt. Two months later, 24-h urinary oxalate decreased from 0.618 to 0.411 mmol/day; 24-h urine citrate increased from 0.58 to 1.10 mmol/day. Six months later, an oxalate absorption test was performed. The patient swallowed a capsule, soluble in gastric juice, containing 50 mg (0.37 mmol) sodium [13C2]oxalate corresponding to 33.8 mg of [13C2]oxalic acid. The amount of labeled oxalate, excreted in urine, was measured by a gas chromatographic-mass spectrometric assay. Oxalate absorption, expressed as the percentage of the labeled dose recovered in the 24-h urine after dosing, was 8.3% (reference range: 2.3-17.5%). In addition to other conventional measures, oral administration of O. formigenes or lactic acid bacteria mixture to promote bacterial degradation of oxalate in the gut, and thus combat hyperoxaluria, may play a role in prevention of calcium oxalate kidney stones.
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PMID:Hyperoxaluria, hypocitraturia, hypomagnesiuria, and lack of intestinal colonization by Oxalobacter formigenes in a cervical spinal cord injury patient with suprapubic cystostomy, short bowel, and nephrolithiasis. 1761 9

Urinary tract infections, most of which are biofilm infections in catheterized patients, account for more than 40% of hospital infections. Bacterial colonization of the urinary tract and catheters causes not only infection but also other complications such as catheter blockage by bacterial encrustation, urolithiasis and pyelonephritis. About 50% of long-term catheterized patients face urinary flow obstruction due to catheter encrustation, but no measure is currently available to prevent it. Encrustation has been known either to result from metabolic dysfunction or to be of microbial origin, with urease positive bacterial species implicated most often. Infectious calculi account for about 15-20% of all cases of urolithiasis and are often associated with biofilm colonization of a long-term indwelling urinary catheter or urethral stent. The use of closed catheter systems is helpful in reducing such problems; nevertheless, such a system only delays the inevitable, with infections emerging a little later. Various coatings intended to prevent the bacterial adhesion to the surface of catheters and implants and thus also the emergence of biofilm infections, unfortunately, do not inhibit the microbial adhesion completely and permanently and the only reliable method for biofilm eradication remains the removal of the foreign body from the patient.
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PMID:[Urinary catheter biofilm infections]. 1857 9


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