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PubMed1993

Gall stone recurrence and its prevention: the British/Belgian Gall Stone Study Group's post-dissolution trial.

The British/Belgian Gall Stone Study Group (BBGSG) post-dissolution trial was a prospective, multicentre, randomised, double blind trial of: (i) low dose ursodeoxycholic acid, (ii) placebo, and (iii) a high fibre, low refined carbohydrate diet in the prevention of gall stone recurrence in patients with complete gall stone dissolution. Further aims included establishing the timing and frequency of recurrence and its association with biliary symptoms, a comparison of the sensitivity of ultrasonography v oral cholecystectography in detecting recurrent stones, and a search for risk factors predicting recurrence. Ninety three patients entered the study, and 82 were followed up for up to five years (mean (SEM) 28 (1.5) months) with six monthly ultrasonography and yearly oral cholecystectography. There were 21 recurrences (26 by oral cholecystectography or ultrasonography, or both), only two of which were symptomatic, which were detected between 12 and 42 months after trial entry. This corresponded to an actuarial recurrence rate of 33.9 (7.0%) by lifetable analysis at 42 months and subsequently. There were four recurrences in the ursodeoxycholic acid, six in the placebo, and 11 in the diet groups, corresponding to 21.9 (9.9)%, 27.4 (10.1)%, and 45.8 (12.4)% respectively at 42 months by lifetable analysis (NS). Variables including age, obesity, menopausal state, pregnancy, and oestrogen containing drugs were not shown to affect recurrence rate. Men had more frequent recurrence than women (NS). Patients who had had multiple stones experienced more recurrences than did those with single stones (NS). Recurrence did not occur in patients who took non-steroidal anti-inflammatory drugs (NSAIDs) (p < 0.02). The stone free interval between stone dissolution and trial entry proved to be important--those stone free > nine months had a recurrence rate of only 12.7 (6.0)% at 42 months compared with 55.4 (12.5)% in those stone free < nine months (p < 0.01). There was imbalance between the ursodeoxycholic acid and placebo groups for this factor, and after applying a statistical correction, the adjusted recurrence rate in the ursodeoxycholic acid group was 15% compared with 30% in both placebo and diet groups (NS). These data suggest that after medical dissolution, the risk of gall stone recurrence is not reduced by a high fibre, low refined carbohydrate diet: it may be lowered, but not abolished, by low dose ursodeoxycholic acid.

Adult↗

PubMed1997

Glycosaminoglycan content of Ca-oxalate stone matrix. Effect of this factor on stone fragility.

To evaluate the fragility of Ca-oxalate monohydrate stones in terms of high energy shock wave effectivity, we measured the glycosaminoglycan (GAG) content of the organic stone matrix of 35 patients who had undergone extracorporeal shock wave lithotripsy (ESWL) treatment for renal pelvic stones. The patients were classified into 3 different groups with respect to the rate of stone disintegration. While group I consisted of patients in whom only one ESWL session was needed to complete disintegration, in group II there were patients requiring 3 or more sessions for complete stone disintegration. On the other hand, patients in whom no sign of disintegration was observed despite 3 ESWL sessions constituted group III. Following this procedure, comparative evaluation of the GAG content of the stone matrix per dry stone weight in each group revealed a statistically significant difference between the first 2 and the 3rd group (p < 0.05). Our results indicated that as the GAG content of the stone matrix decreased, the efficiency of the shock waves on stone disintegration also prominently decreased, disintegration being impossible in some cases. On the other hand, the stones which were found to have higher amounts of GAGs in the organic matrix tended to be more fragile and were easily disintegrated with shock waves. In our study group the chemical composition of Ca-oxalate monohydrate stones, e.g. the matrix GAG content, seemed to be important with regard to the disintegrative effect of high energy shock waves.

Adult↗

PubMed1993

Extracorporeal shock wave lithotripsy for obstructed proximal ureteral stones. A prospective randomized study comparing in situ, stent bypass and below stone catheter with irrigation strategies.

In an attempt to assess the usefulness of a ureteral stent in facilitating disintegration of obstructed proximal ureteral stone with extracorporeal shock wave lithotripsy (ESWL), a prospective randomized study on 120 patients with ultrasonic evidence of hydronephrosis whose stone sizes were greater than 1.0 x 0.6 cm on KUB film and located above the level of L5 were allocated into three distinct treatment strategies: group 1: in situ without stone manipulation; group 2: bypass stones with stent, and group 3: placement of a catheter below stone with continuous saline irrigation. Of 77 patients, 26, 27 and 24 in each group, followed up for a period of 6 months with sufficient data for analysis, the stone-free rates were 76.9, 59.3 and 62.5%, respectively. The average number of shock waves delivered to accomplish a stone-free state were 3,245, 3,250 and 3,880 for individual groups and the comparisons among them were statistically insignificant (p's > 0.1). ESWL retreatment was common, being 33.3, 29.4 and 43.8%, respectively. Hydronephrosis has a major impact on the outcome of ESWL treatment, as more stone-free cases were found in the mildly hydronephrotic category than in the severer counterparts. About 90% of cases who finally were stone-free, passed all their stone fragments within 28 days. Ancillary procedures were needed in 13 (16.9%), 7 received ureterolithotomy, whilst 6 were removed of their stones by ureteroscopy.

Adult↗

PubMed1998

Proteins in renal stones and urine of stone formers.

Knowledge of the essential characteristics of macromolecules constituting the organic matrix of the nidus of urinary stones is required to understand the mechanism of urolithogenesis. The aim of this study was to isolate and characterise those stone nidus proteins. Using an extraction buffer containing SDS and beta-mercaptoethanol, we were able to overcome known problems of protein isolation from urinary stone matrix. These proteins were characterised by a strong tendency to aggregate under reducing and denaturing conditions. On SDS-PAGE, their molecular weights range from < or = 12 to 66 kDa. Antisera raised against stone matrix proteins showed a cross-reactivity between proteins isolated from different stones irrespective of their origin or mineral composition. Moreover, urinary proteins from stone formers also cross-reacted with these whereas there was no reaction with urinary proteins of non-stone formers. Western blotting confirmed these findings. Given the above summarised properties, it can be safely concluded that these proteins are prevalent in urines of stone formers, that they are selectively incorporated into renal stones of all aetiologies, and that they most likely have a role in nidus and, therefore, early stone formation.

Blotting, Western↗

PubMed1992

Stone surface area determination techniques: a unifying concept of staghorn stone burden assessment.

The use of stone surface area measurements obtained from standard radiographs provides a more accurate and reproducible assessment of stone burden when reporting results and treatment recommendations for staghorn calculi. Techniques for determining stone surface area include use of graph paper, planimeter or computerized image analysis. The use of graph paper is inefficient while planimeters suffer from significant variation for areas less than 500 mm.2 (more than 5%). Computer image analysis is accurate, rapid and easiest to perform. Software programs compatible with microcomputers are readily available making assessment of stone surface area practical and inexpensive. Stone surface area showed close correlation to stone volume as measured by 3-dimensional computerized tomography (correlation coefficient 0.84, p = 0.005). Stone surface area determination enables more accurate reporting of treatment results and, thus, recommendations based upon stone burden. Comparison of data between institutions becomes more meaningful if stone surface area is used. Stone surface area also provides a useful basis to study and compare trends of treatment within a single institution.

Humans↗

PubMed1998

Dissolution of gallbladder stones with methyl tert-butyl ether and stone recurrence: a European survey.

Since there are now several ways to treat symptomatic gallstone disease, one is able to select treatment on the basis of the patient's comfort, the practicability, effectiveness, and side effects of the technique, and the relative costs. In order to assess the present status of contact dissolution with methyl tert-butyl ether with regard to these aspects, the present enquiry reports the data of 21 European hospitals. Eight hundred three patients were selected for contact litholysis of cholesterol gallbladder stones using methyl tert-butyl ether. Percutaneous transhepatic puncture of the gallbladder was performed under x-ray or ultrasound guidance. Dissolution rate, side effects, and treatment times of 268 patients from one single center were compared to those of 535 patients from the other 20 centers. Two hundred sixty-four patients were followed for five years to assess stone recurrence. Physicians were asked how they assessed the expenditure of the method, the discomfort to the patients, and the staffing situation. Patients were asked to indicate their acceptance on an analog scale. Puncture was successful in 761 (94.8%) patients. Prophylactic administration of antibiotics was not necessary. Stones were dissolved in 724 (95.1%) patients. In 315 (43.5%) sludge remained in the gallbladder. The most severe complication was bile leakage, which led 12 (1.6%) patients to have elective cholecystectomy. Toxic injuries due to the ether were not reported. Method-related lethality amounted to 0%, 30-day-lethality to 0.4%. Stone recurrence rate was about 40% in solitary stones and about 70% in multiple stones over five years. Patients with multiple stones developed recurrent stones almost twice as often as those with solitary stones. The probability of stone recurrence in patients with sludge in the gallbladder after catheter removal was not statistically significantly different from those without sludge. Seventy to 90% of the centers found the puncture to be simple and not distressing for patients and the relation between expenditure and therapeutic success to be acceptable. The acceptance of contact litholysis by the patients was excellent. Contact litholysis when applied by an experienced team provides real advantages in the treatment of gallstone disease. The method is technically simple, well accepted by the patients, and can be easily applied in community hospitals. Contact litholysis may be of particular value in patients who are not suitable for anesthesia or surgery.

Adolescent↗

PubMed1993

Results of extracorporeal shock wave lithotripsy of gall bladder stones in 693 patients: a plea for restriction to solitary radiolucent stones.

During a period of 24 months 693 consecutive patients with symptomatic gall bladder stones (526 males, 167 females; mean age 51 years, range 18-89) were treated by extracorporeal shock wave lithotripsy with a Piezolith 2300. The procedure was carried out on an out-patient basis without analgesics or sedatives. Concomitant chemolitholytic treatment (ursodeoxycholic and chenodeoxycholic acid 7.5 mg/kg/day each) was administered until three months after total fragment clearance for a maximum therapy period of 1.5 years. In 601 patients with radiolucent stones complete clearance of all fragments was obtained after three, six, 12, and 18 months in respectively 20, 41, 64, and 78%. Actuarial analysis of the subgroups according to the stone mass (size and number) selected an ideal patient population with solitary stones less than 20 mm diameter (84% stone free after one year). The results are significantly less good when the greater the number of stones or their maximal diameter increases. Treatment was interrupted in 3.6% of the patients. In 90 sludge or fragments remain present. Twenty five patients were lost to follow up for non-biliary reasons. Stone recurrence was 5.7% at one year and was observed both in patients with solitary and multiple stones. A cost effectiveness analysis suggests that laparoscopic cholecystectomy is the most effective and economic solution, although extracorporeal shock wave lithotripsy for solitary radiolucent stones less than 2 cm is cheaper than conventional cholecystectomy. Extracorporeal shock wave lithotripsy for multiple stones is the most expensive and least effective option.

Adolescent↗

PubMedDate not supplied

Stone composition, metabolic profile and the presence of the gut-inhabiting bacterium Oxalobacter formigenes as risk factors for renal stone formation.

OBJECTIVE: To examine stone composition, metabolic evaluation and colonization of Oxalobacter formigenes as risk factors for renal stone formation. SUBJECTS AND METHODS: Eighty patients with renal stones and 70 healthy controls were enrolled in the study. Of the 80 patients, 48 were first-time stone formers (FSF) and 32 were 'recurrent' stone formers (RSF), recurrent indicating 2 or more episodes of stone formation. Stone analysis by X-ray crystallography, 24-hour urine metabolic profile and detection of O. formigenes-specific DNA by PCR were performed for each patient. Detection of O. formigenes was also performed on 45 and urinary metabolic profile on an additional 25 controls. RESULTS: Calcium oxalate monohydrate was the major component of stones, hyperoxaluria and hypocitraturia were the most common urinary abnormalities in the 80 patients, 46% of RSF patients had hypercalciuria. Urinary abnormalities were far less frequent in the controls, with the exception of hypocitraturia (40%). Of the urinary metabolites, only calcium levels were significantly different (p < 0.05) between FSF (6.50 +/- 4.08 mmol/24 h) and RSF (8.21 +/- 5.26 mmol/24 h) patients. Colonization of O. formigenes was higher in controls (62.2%) than in FSF (33.3%) or RSF (28%) patients, it was least in patients with more than 4 episodes (7%) of stone formation. CONCLUSION: The findings indicate that lack of colonization of O. formigenes may be an important risk factor for recurrence of stone formation (calcium oxalate monohydrate).

Adult↗

PubMed1991

Stone fragility--measurement of stone mineral content by dual photon absorptiometry.

We measured the mineral content of urinary tract stones by dual photon absorptiometry, which is widely used for the analysis of bone mineral content, and compared the values of the stones by dual photon absorptiometry (DPA values) with the results of an in vitro fracture study as well as those of an in vivo extracorporeal shock wave lithotripsy treatment study. The results of a preliminary experiment showed that the DPA values of 20 urinary tract stones reflected actual stone mineral content. As a result of the in vitro fracture study, the DPA value calculated by volume of a struvite stone, which was the most easily disintegrated, was the lowest (0.53 g/cm3). The DPA values of calcium oxalate monohydrate and apatite stones, which poorly disintegrated, were the highest (0.98, 1.01 g/cm3). The DPA value of calcium oxalate dihydrate, which moderately disintegrated, was 0.86 g/cm3. By the in vivo extracorporeal shock wave lithotripsy treatment study, the total DPA values of stones measured before extracorporeal shock wave lithotripsy treatment in 12 patients were 0.73 +/- 0.34 g in successful cases and 1.92 +/- 0.43 g in unsuccessful cases with a significant difference between the two (p less than 0.05). These results showed that the measurement of stone mineral content by dual photon absorptiometry was useful in predicting the fragility of stones against shock waves before performing extracorporeal shock wave lithotripsy treatment for patients with urinary tract stones.

Absorptiometry, Photon↗

PubMed2002

Urinary stone risk factors in the siblings of patients with calcium renal stones.

PURPOSE: We determined which, if any, urinary stone risk factors accurately discriminate stone forming and nonstone forming siblings of patients with calcium renal stones. MATERIALS AND METHODS: A total of 252 siblings of stone formers provided 2, 24-hour urine samples, which were sent overnight and analyzed at a central laboratory. Standard stone risk factors were measured and the supersaturation of calcium oxalate, calcium phosphate and uric acid was calculated. RESULTS: Discriminant functions were derived for each gender by multivariate analysis. In stone forming sisters higher urinary calcium and pH discriminated with a success rate of 70%. In stone forming brothers higher urinary calcium, lower urinary potassium and older age discriminated with a success rate of 79%. CONCLUSIONS: Select urinary measurements as well as age classify siblings into those with and without stones with fair accuracy. Calcium excretion and urinary pH in females, and calcium excretion, urinary potassium and age in males are feasible identifiers of stone forming siblings. To determine whether these measurements can be used to predict new stone onset may require years of observation of our current cohort.

Adult↗

PubMed2003

[Urinary stones and urinary tract abnormalities. Is the stone composition independent of the anatomical abnormality?].

INTRODUCTION: More than ten per cent of stones are associated with a urinary tract abnormality. To verify whether the malformation influences stone composition, we studied the composition of stones observed in fifteen urological abnormalities. MATERIAL AND METHOD: This study is based on 1,461 stones associated with a clearly defined malformation analysed by infrared spectroscopy plus 402 bladder stones in men with benign prostatic hyperplasia. RESULTS: In this series of 1,863 abnormalities, 732 (39.3%) involved the kidney, 561 (30.1%) involved the ureter and 570 (30.6%) involved the lower tract. Whewellite stones were predominant in all renal abnormalities with the exception of cysts, which were mainly associated with uric acid. The main differences concerned the second constituent: weddellite in horseshoe kidneys, carbapatite in Cacchi-Ricci disease and caliceal abnormalities. Struvite was uncommon (<10%). Whewellite was the main component in ureteric abnormalities except for megaureter and reflux in which carbapatite was predominant. Struvite was present in 10% to 30% of stones. Vesicourethral abnormalities were accompanied by calcium and magnesium phosphate stones (90% of cases), and struvite was present in 58% to 90% of cases. The exception to this general rule was bladder stones associated with benign prostatic hyperplasia, in which the main component was uric acid. CONCLUSION: Significant differences in stone composition were observed as a function of anatomical abnormalities reflecting the fact that some abnormalities add infectious or metabolic risk factors to anatomical factors.

Female↗

PubMed2005

[Stone Cone: a device that prevents ureteral stone migration during intracorporeal lithotripsy].

OBJECTIVES: Proximal migration of stone fragments during ureteroscopic lithotripsy is a common problem influenced by pressure of irrigation solution, type of energy for lithotripsy, site and degree of fixation of the stone to the ureteral wall, and degree of proximal ureteral dilation. The Stone Cone (Boston Scientific & Spencer) is a device that helps to prevent proximal migration of fragments and favours a safe extraction during ureteroscopic lithotripsy. TECHNIQUE: The Stone Cone is an helical device made of stainless steel and nitinol alloy, which consists of an internal guide wire and a sheath-like radiopaque catheter with a 3 Fr. calibre. Once the cone is placed above the stone it is maintained in that position during lithotripsy to avoid fragment migration. The external catheter is used to coil and unroll the cone, and allows access to place the cone above the stone. METHODS: We describe two cases of urinary calculi in the left lumbar ureter treated by ureteroscopy and intracorporeal lithotripsy with holmium YAG laser using the Stone Cone to avoid migration of fragments. RESULTS: One month after surgery no lithiasic fragments were observed in the imaging tests. CONCLUSIONS: The Stone Cone decreases the need to perform repeated ureteral instrumentations, and is also a safer and simpler method for the extraction of stone fragments. The use of Stone Cone seems to have more advantages than Dormia's basket during ureteroscopic lithotripsy in terms of lower incidence of residual fragments and reoperation rate.

Adult↗

PubMedDate not supplied

Endoscopic lithotripsy of bile duct stones using a new laser with automatic stone recognition.

Biliary stones can be removed in 85% to 90% of patients using endoscopic sphincterotomy; in the rest alternative methods are required. Thirty-eight consecutive patients in whom conventional methods had failed underwent laser lithotripsy with a new laser system. A flashlamp-pumped pulsed laser with rhodamine 6G as dye (594 nm) has a tissue-stone recognition system that can identify bile duct stones by analyzing backscattered light and interrupt the pulse in case of tissue contact (Lithognost, Telemit, Munich, Germany). Access of the 0.25- or 0.30-mm-diameter laser fiber to the stones was achieved perorally in 18 patients. In 13 of these cases, eccentrically located stones in the middle or proximal common bile duct were targeted with a 3.4-mm miniscope introduced through a standard duodenoscope. Fluoroscopically guided peroral lithotripsy was performed in 5 patients with stones in the distal common bile duct that could be approached with a standard ERCP catheter. Percutaneous cholangioscopic laser lithotripsy was carried out in 20 patients with stones not amenable to retrograde techniques. The mean number of bile duct stones per patient was 3.6, and the average diameter of the largest stone of each patient was 25 mm (range, 8 to 52 mm). The bile ducts were cleared in all but 1 patient in a mean number of 1.3 sessions lasting 15 to 115 minutes (mean, 60). No laser-related complications were observed. The Lithognost laser was successfully used in 37 of 38 patients referred for the removal of difficult bile duct stones.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1996

Peroral laser lithotripsy of difficult intrahepatic and extrahepatic bile duct stones: laser effectiveness using an automatic stone-tissue discrimination system.

OBJECTIVES: The use of laser lithotripsy with an integrated stone-tissue discrimination system is an ambitious treatment modality for bile duct stone fragmentation. The aim of our prospective study was to determine the effectiveness and safety of the laser system and to find whether it reduced the need for choledochoscopy. METHODS: Thirty patients with complicated bile duct stones were treated perorally with a flashlamp-pulsed Rhodamine-6G dye laser and an automatic stone-tissue discrimination system. Initial treatment sessions were performed under fluoroscopic guidance in each patient and switched to choledochoscopic control if the stone could not be approached properly. RESULTS: Eighteen of 19 patients with extrahepatic bile stones were treated under fluoroscopic control; 17 of 19 patients were successfully treated through laser therapy. In nine of the patients with intrahepatic stones (n = 11), choledochoscopy was necessary for sufficient laser lithotripsy; seven of those patients became stone-free. Twenty-four of 30 patients (80%) were stone-free after sole laser therapy. Combined with other methods, the overall success rate was 27/30 (90%). Therapy-related mortality was 0%. CONCLUSIONS: Laser lithotripsy is effective and safe. The stone-tissue discrimination system facilitates therapy under fluoroscopic control and precludes the need for choledochoscopy, which is highly significant (p <0.001) if the calculi are extrahepatically located.

Adult↗

PubMed1995

Analysis of the soluble organic matrix of five morphologically different kidney stones. Evidence for a specific role of albumin in the constitution of the stone protein matrix.

Our aims were to analyze the protein composition of the organic matrix of urinary stones and to investigate the role of albumin in its constitution. Five different morphological types of stones were studied. Proteins extracted from the stone were submitted to sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and analyzed by immunoblotting with antibodies to 13 urinary proteins. Nine of the 13 proteins were found in all types of stone: human serum albumin (HSA), alpha 1-acid glycoprotein (alpha 1-GP), alpha 1-microglobulin (alpha 1-M), immunoglobulins (Igs), apolipoprotein A1 (apo-A1), transferrin (Tr), alpha 1-antitrypsin (alpha 1-T), retinol-binding protein (RBP) and renal lithostathine (RL). The beta 2-microglobulin (beta 2-M) was present only in calcium oxalate and uric acid stones. In contrast, ceruloplasmin, haptoglobin and Tamm-Horsfall protein (THP) were detected in none of them. Because HSA appeared as the major protein component in all stones, we wondered whether it might play a specific role in the constitution of the stone matrix. Association of HSA with urinary proteins that were present in stones was demonstrated by showing that proteins present in the matrix comigrated with HSA on gel filtration, whereas proteins that were absent did not. Moreover, HSA induced the binding of stone matrix proteins to an albumin-specific affinity column. Finally, we evidenced HSA binding to calcium oxalate monohydrate (COM) crystals in a solution similar to urine.(ABSTRACT TRUNCATED AT 250 WORDS)

Albumins↗

PubMed1998

Calyceal stones: fate of shock wave therapy with respect to stone localization.

In a retrospective analysis the results of extracorporeal shock wave lithotripsy (ESWL) treatment were evaluated in patients with renal stones according to calyceal localization of treated stones. The 198 patients who underwent ESWL with the Dornier MPL 9000 were analyzed for success rate, complication rate, residual fragments, regrowth and recurrence rates. Totally 210 calyceal calculi located in different portions of the kidney have been comparatively evaluated. No major complications were noted during or after ESWL. Some minor complications such as flank pain, renal colic, haematuria were observed. Flank pain was observed during ESWL treatment especially in patients with upper calyceal stones. Although stone-free and residual fragment rates were similar in pelvic, upper and middle calyces, patients with lower calyceal and pelvicalyceal stones had high residual fragment rate and lower stone-free rate. Patients with stones in the lower calyces or pelvicalyces had high recurrence and regrowth rates (p < 0.05). ESWL has been considered as the optimal treatment modality for most upper urinary tract calculi. It is especially effective in patients with pelvic, upper and middle calyceal stones. Patients with lower calyceal stones often failed to eliminate the fragments, hence had high recurrence and regrowth rates.

Adolescent↗

PubMed1987

Triamterene and renal stone formation: the influence of triamterene and triamterene stones on calcium oxalate crystallization.

A constant composition method has been used to compare the effects of triamterene renal stone material, synthetic triamterene precipitates, and soluble triamterene on the nucleation and crystallization kinetics of calcium oxalate in aqueous solution in vitro. Crystallization studies have been carried out with the concentrations of calcium and oxalate ions maintained constant by the potentiometrically controlled addition of concentrated reagent solutions containing these ions. Triamterene renal stones were found to be much less effective than synthetic triamterene towards promoting the nucleation and crystallization of calcium oxalate from supersaturated solution. Renal stones composed of triamterene and matrix did not significantly enhance the deposition of calcium oxalate compared to nonseeded controls. The triamterene stones were also found to be ineffective in promoting calcium oxalate crystallization compared to other precipitates thought to be involved in the etiology of stone disease such as calcium hydroxyapatite. For stones of mixed triamterene/calcium oxalate composition, the enhancement of the nucleation and crystallization of calcium oxalate was directly related to the calcium oxalate content of the stone seed material. The presence of soluble triamterene or its metabolites in solution did not influence the crystallization kinetics of pure calcium oxalate seed materials. The results of this study indicate that triamterene in stones does not significantly contribute to further stone development through the enhancement of calcium oxalate crystallization processes.

Calcium Oxalate↗

PubMed2006

An angulated common bile duct predisposes to recurrent symptomatic bile duct stones after endoscopic stone extraction.

BACKGROUND: Endoscopic sphincterotomy and stone extraction are standard procedures for the removal of bile duct stones. Stone recurrence can, however, occur in up to 25% of cases. Risk factors have been poorly defined, but are believed to be related to bile stasis. This study investigated whether an angulated common bile duct (CBD) that may predispose to bile stasis influences symptomatic stone recurrence after successful endoscopic therapy. METHODS: This study included 232 consecutive patients (mean age, 64.1 years; 86 men) who had undergone therapeutic endoscopic retrograde cholangiopancreatography for bile duct stones. Data from the follow-up period (36 +/- 17 months) were obtained from medical records and patient questioning. Common bile duct angulation and diameter were measured from the cholangiogram after stone removal. RESULTS: Symptomatic bile duct stones recurred in 16% of the patients (36/232). Three independent risk factors were identified by multivariate analysis: an angulated CBD (angle, < or = 145 degrees; relative risk [RR], 5.2; 95% confidence interval [CI], 2.2-12.5; p = 0.0002), a dilated CBD (diameter, > or = 13 mm; RR, 2.6; 95% CI, 1.2-5.7; p = 0.017), and a previous open cholecystectomy (RR, 2.7; 95% CI, 1.3-5.9; p = 0.0117). Gender, age, urgency of procedure, or a periampullary diverticulum did not influence the recurrence rate. CONCLUSIONS: Angulation of the CBD (< or = 145 degrees) on endoscopic cholangiography, a dilated CBD, and a previous open cholecystectomy are independent risk factors for symptomatic recurrence of bile duct stones. The findings support the role of bile stasis in stone recurrence. Further studies using these data prospectively to identify high-risk patients are warranted.

Adolescent↗