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Glycosaminoglycans and struvite calculi.

Glycosaminoglycans (GAGs) are suspended in urine and are present on tissue surfaces in the urinary tract. Consequently, they have the potential to influence any pathological disorder in this environment, including urinary tract infections by Proteus mirabilis and struvite (NH4MgPO4.6H2(0)) urolithiasis. Although GAGs, suspended in urine, may inhibit the formation of other types of calculus minerals, no such effect has been reported in struvite calculi. Nevertheless, GAGs are a major component of the organic matrix of all types of urinary calculi. In contrast, there is evidence that the GAG layer on the bladder surface may act as a defence mechanism against infection by inhibiting bacterial adhesion. More studies are needed to elucidate fully the role of GAGs in urinary infections and struvite urolithiasis.

Glycosaminoglycans↗

Low-angle X-ray scattering signatures of urinary calculi.

This is the first reported use of low-angle X-ray scattering for the investigation of urinary calculi. Low-angle X-ray scattering (LAXS) measures the diffraction of a broad spectrum of X-rays at a single angle and uses a conventional diagnostic X-ray beam, and could thus be developed for use in vivo. A total of 45 calculi were investigated using this technique. Calcium oxalate stones showed a bimodal signature with peaks of almost even photon energies. Signatures for the other stone types were less well-defined. The results are discussed in more detail below. Our preliminary results show that the technique is capable of distinguishing between calcium oxalate stones and other stone types in vitro. Further work is in progress to correlate the results of this technique with objective parameters of stone hardness.

Humans↗

Management of complex renal calculi.

The treatment of small renal pelvic and ureteric calculi can be performed with relative safety and efficacy using lithotripsy or an endourological method. There remains however, a proportion of stones that are resistant to these methods because of their anatomical position, physical composition or sheer size. To these stones must be applied a treatment strategy using the variety of techniques to their maximum advantage. This article aims to review the accumulated experience on the management of these more complex urinary calculi.

Calcium Phosphates↗

The influence of calcium content of water, intake of vegetables and fruit and of other food factors upon the incidence of renal calculi.

An area of high incidence of renal calculi in Northern England and Scotland has been found to coincide with an area of soft water supply. However, in Wales and South West England the equation of soft water with high incidence of urolithiasis is lacking, and an enquiry into regional variations in diet reveals that a high intake of fruit and vegetables may protect against renal calculi.

Calcium, Dietary↗

Analysis of calcium, iron, copper and zinc contents of nucleus and crust parts of urinary calculi.

In this study we compared the concentrations of calcium, iron, copper and zinc in the nucleus and the crust parts of various kinds of urinary calculi. We found that the mean concentrations of iron, zinc and copper in the nucleus parts of the stones were statistically higher than those in the crust parts. We attempted to explain this finding by two different approaches. Inter- and intra-correlations were also sought between the elements in the nucleus and crust parts. These correlations suggested a complex relationship between the elements of the urinary calculi.

Calcium Oxalate↗

Extracorporeal shock wave lithotripsy and xanthine calculi in Lesch-Nyhan syndrome.

We report a case of Lesch-Nyhan syndrome (LNS) with urinary xanthine calculi. At eight years of age calculi in the renal pelvis were successfully disintegrated by extracorporeal shock wave lithotripsy (ESWL) without any complications. Follow-up sonography is very useful for management of patients with LNS, particularly when they are on allopurinol therapy.

Allopurinol↗

Combined oral and local therapy for the dissolution of urinary calculi.

The factors underlying the formation of Ca-phosphate and struvite calculi, as well as the present possibilities for oral and local therapy, their advantages and drawbacks are discussed in the light of published evidence. In this context a clinical case of multiple injuries is reported in which practically complete chemolitholysis has been achieved by combined oral and local therapy. The rapid growth of the calculi and their alarming tendency to recurrence in case of inadequate treatment is emphasized. The therapeutic method used in this case is regarded as suitable for practical purposes.

Administration, Oral↗

Experimental study of marginal wedge resection and its practical application in the surgical therapy of staghorn calculi.

A surgical procedure for staghorn calculi, which are inaccessible to conservative therapy, is described. It not only provides for complete elimination of the calculus but may also contribute to the prevention of recurrences. The technique of marginal wedge excision of the renal parenchyma, developed in animal studies, is described in detail and 11 surgical cases are reported. Removal of staghorn calculi was successful all throughout, and renal function remained unaffected by the intervention in all of the cases. Recurrences were confined to a single case. The procedure is safe, it involves no greater surgical strain than does marginal nephrotomy, but its short-term metaphylactic results seem more promising. Assessment of the long-term results awaits further observations.

Adult↗

Percutaneous ultrasonic lithotripsy of symptomatic renal calculi in children.

Percutaneous ultrasonic lithotripsy of upper urinary tract lithiasis is a well-established procedure in adults. We successfully applied this technique to completely remove symptomatic renal calculi in two children with idiopathic hypercalciuria. The procedure was well tolerated and no complications occurred. Both patients were discharged within 4 days of the lithotripsy. This method is an alternative to surgery for the removal of large or impacted calculi from the upper urinary tracts of pediatric patients.

Adolescent↗

Intrahepatic calculi associated with cholangiocarcinoma.

A unique case of hepatolithiasis associated with cholangiocarcinoma is described. The intrahepatic calculi consisted mainly of cholesterol rather than calcium bilirubinate. A bacteriological study of the intrahepatic and gallbladder bile was negative, though bacterial infection of the bile duct has been considered a main factor responsible for formation of intrahepatic calculi.

Adenoma, Bile Duct↗

Extracorporeal shock wave lithotripsy of staghorn calculi.

A total of 260 patients underwent treatment with extracorporeal shock wave lithotripsy (ESWL). Staghorn calculi were found in 32 cases. In carrying out ESWL for staghorn calculi, double pigtail stent was previously retained in principle. When the ureter was occluded by stone street in case a fever of more than 38 degrees C lasted for 4-5 days after the first treatment with ESWL, percutaneous nephrostomy (PNS) was performed. In ESWL treatment alone a large number of shock waves were required, but double pigtail stent and PNS were used in combination individually, and larger stones were treated by the same waves. When combination therapy was used, hospital stay was short and the rate of remaining stones was low. Our therapeutic conclusions are discussed.

Adult↗

Open stone surgery: is it still a preferable procedure in the management of staghorn calculi?

We reviewed 43 patients with staghorn calculi to determine the effectiveness of various treatment modalities such as extracorporeal shock wave lithotripsy (ESWL) monotherapy, ESWL and percutaneous nephrolithotomy (PCNL) combined therapy, and open stone surgery. While ESWL monotherapy and ESWL+PCNL were performed in 25 and 8 patients, respectively, 10 patients underwent open stone surgery. Of the 25 patients treated with ESWL, 8 were stone-free, whereas 4 out of 8 patients treated with ESWL+PCNL and 8 out of 10 patients treated with open surgery were stone-free. The complications of ESWL monotherapy consisted of pyelonephritis in one patient, and stone street formation in three. In the group of ESWL+PCNL, one patient developed pyonephrosis, and another perinephritic abscess. No serious complication was noted in patients who underwent open surgery, but an average of 525 ml of blood transfusion was required. We conclude that open stone surgery, although invasive, is still beneficial in the treatment of staghorn calculi.

Adolescent↗

DC plasma emission spectroscopic analysis of pancreatic calculi.

Previous studies on pancreatic calculi (PC) from alcoholic pancreatitis and our recent studies on calculi from tropical pancreatitis have shown them to consist mainly of CaCO3 with minute quantities of Mg. However, no attempt was made to look for other elements in PC. This is because of the difficulty in obtaining adequate samples of PC, coupled with the technical limitations in analyzing multi-elements from small samples. In this study, our aim was to analyze the major, minor and trace elements of PC from different parts of the world. DC plasma emission spectroscopy, a modern method that permits determination of multiple elements from small samples, was used in elemental analysis. We identified 17 elements in addition to calcium. Selenium was looked for but was absent. It was interesting that the elemental composition of PC in four patients from different geographical areas with divergent etiological factors remained the same. Absence of Se is of interest, as Se deficiency is associated with pancreatic fibrosis in experimental animals and it is often noted in chronic alcoholics and the malnourished. This preliminary study emphasizes the need for analysis of the elemental composition of pancreatic juice in normals and in conditions predisposing to chronic pancreatitis, to understand lithogenesis and possibly also the etiology of, at least, some types of pancreatitis.

Adult↗

[Ureteroscopy (URS) for ureteric calculi].

Distal ureteral calculi (<5 mm) usually pass the ureter spontaneously. Ureteroscopic lithotripsy of distal ureteral calculi shows high stone-free rates with a low complication rate (4%) and is equal to extracorporeal shock wave lithotripsy (ESWL), while ESWL is the primary choice for proximal ureteric stones. Flexible endoscopes are more difficult to handle and should be used only under fluoroscopic control. They are generally used in combination with the holmium:YAG laser and the flexible Lithoclast in the proximal ureter or the renal collecting system. Overall the complication rate of URS is 9-11% with avulsion of the ureteric urothelium being the most common complication. Ureteral perforation, stricture (<1%), impaction of the instrument in the ureter with consequent ureteral laceration, extravasation of stones, and bleeding in the urogenital tract are complications of URS but are minimal in the hands of a well-trained and skilled surgeon.

Humans↗

Simultaneous determination of composition of human urinary calculi by use of artificial neural networks.

A new chemometric method, which uses artificial neural networks (ANN), is presented for determination of the composition of urinary calculi. The selected constituents were whewellite, weddellite, and uric acid from which approximately 40% of the urinary calculi obtained from Macedonia patients are composed. The results for the synthetic mixtures were better then those obtained by partial least squares (PLS) regression or by the principal component regression (PCR), because neural networks have better prediction capacity. The generalization abilities of the optimized neural networks were checked using the standard addition method on carefully selected real natural samples.

Humans↗

The use of tamsulosin in the medical treatment of ureteral calculi: where do we stand?

It has recently been demonstrated that specific adrenoceptors subtypes (alpha(1A)/alpha(1D)) are prevalent in the distal part of the ureter, a finding supporting the interesting results obtained by different groups with the use of tamsulosin in the treatment of distal ureteral calculi. We performed a prospective randomized study to evaluate the effects of the addition of tamsulosin on our standard pharmacological therapy for the treatment of selected ureteral stones. A total of 64 patients referred to our department for the management of symptomatic ureteral calculi were considered. Patients were randomly divided into two treatment groups: group A (n=32) who received diclofenac (100 mg/daily) plus aescin (80 mg/daily) and group B (n=32) who received the same therapy plus tamsulosin (0.4 mg/daily) for a maximum of 2 weeks. No significant differences were found between the groups for age, gender distribution and mean stone size measured in the single largest dimension at presentation. The stone expulsion rate was 60% (19/32 patients) for group A and 88% for (28/32) for group B with a mean expulsion time of 7.4+/-2.2 (range 3.5-12) and 4.8+/-2.7 days (range 1.8-10.5), respectively. Group B showed a significant advantage in terms of both expulsion rate (P=0.01) and expulsion time (P=0.005). Different analgesics from those used in the standard treatment regimen were required in ten patients in group A (31%) but only three patients in group B (9%). This difference was significant (P=0.003). Hospitalization for recurrent colic was needed in 21% of patients in group A (7/32) and in 9% in group B (3/32) (P=0.01). Only two patients in each group (6%) experienced minor side effects associated with the expulsive therapy. Our data confirm the efficacy of tamsulosin in the treatment of distal ureteral stones up to 1 cm. This selective alpha-blocker should therefore be included in the pharmacological regimen of patients when a conservative approach is considered in the treatment of ureteral lithiasis.

Adrenergic alpha-Antagonists↗