The relation between biliary lipids, nucleation time, and number of gallbladder stones after percutaneous gallbladder puncture

Assessment of 'nucleation time' as a predictor of cholelithiasis

INTRODUCTION

In the formation of gallstones, crystal nucleation is a key step, which is followed by precipitation and gradual growth of cholesterol crystals.

MATERIALS AND METHODS

A case-control study was carried out among 60 patients (30 patients, 14 males and 16 females, median age of 36 years, range 33-71 years, body mass index (BMI)=25.1+/-0.33 kg/m, who underwent laparoscopic cholecystectomy; 30 control individuals, 15 males and 15 females, median age of 38 years, range 33-70 years, BMI=24.5+/-0.23 kg/m, who underwent laparotomy and who had normal ultrasound scans of the gallbladder and no demonstrable stones). Bile aspirated from the common bile duct was ultrafiltered and anaerobically incubated at 37 degrees C. Incubated bile was examined daily by polarized light microscopy, for appearance of cholesterol crystals. Nucleation time (NT) of bile was assessed as the time taken for the first crystals to appear under polarized light microscopy.

RESULTS

Age and BMI of control individuals were not different to those of cases studied. The overall mean NT was significantly shorter in patients versus controls (mean NT+/-SEM: patients, 1.76+/-0.2 days; vs. controls, 12.74+/-0.4 days, P=0.001). Of control individuals, females demonstrated a shorter NT compared with males (mean NT+/-SEM: females, 11.4+/-0.36 days; vs. males, 14.1+/-0.46 days, P=0.006). In contrast, there was no sex difference in NT in patients (mean NT+/-SEM: females, 1.7+/-0.24 days; vs. males, 1.8+/-0.2 days, P=0.7).

CONCLUSION

NT in control individuals without gallstones was significantly prolonged compared with the NT in patients with established gallstone disease. Among the control individuals, females had a significantly shorter NT than males. Hence, the assessment of NT is predictor of cholelithiasis.

Ten years experience with piezoelectric extracorporeal shockwave lithotripsy of gallbladder stones

BACKGROUND

A critical review of the experience with extracorporeal shockwave lithotripsy (ESWL) of gallbladder stones is needed to clarify whether this method should continue to be applied to patients.

METHODS

Patients with symptomatic gallbladder stones were treated by piezoelectric ESWL according to a prospective protocol between 1988 and 1997. ESWL treatment was limited to a maximum of three (solitary stones <20 mm diameter) to five sessions (larger solitary or multiple stones) and 3000 pulses per session. Univariate and multivariate analyses of pretreatment and treatment variables were performed to investigate their impact on fragmentation efficacy and stone clearance. A tree-based analysis was used to identify prognostically homogenous subgroups of individuals with maximum benefit from ESWL.

RESULTS

Four hundred and eight patients, 76% female and 24% male, with a mean age of 46 (SD, 13) years, were selected for evaluation. Cox regression analysis identified three pretreatment variables with significant prognostic impact: (1) number of gallstones >1 (relative risk, 2.6 (95% CI, 1.9-3.5)), (2) size of stones >17 mm (1.7 (1.4-2.2)), and (3) computed tomography (CT) density of stones >55 Hounsfield units (H) (1.4 (1.1-1.8)). According to tree-based analysis, the stone clearance rate after 1 year was 85% (95% CI, 75-91%) for solitary stones <16 mm, 79% (70-86%) for solitary stones > or =16 mm with a CT density <84 H, 45% (32-55%) for solitary stones > or =16 mm with a CT density > or =84 H, and 42% (30-51%) for multiple stones. Five years after stone clearance, recurrence occurred in 43% of patients (95% CI, 39-47%).

CONCLUSIONS

ESWL treatment showed an acceptable stone clearance in the case of small solitary gallbladder stones (<16 mm) or larger solitary stones with a CT density <84 H, but a very low success rate in the case of multiple stones. The poor long-term success, however, is an important argument against the use of ESWL of gallbladder stones.

Phosphatidylcholine-enriched diet prevents gallstone formation in mice susceptible to cholelithiasis

Cholesterol gallstones affect approximately 10-15% of the adult population in North America. Phosphatidylcholine (PC) is considered to be the main cholesterol solubilizer in bile. This study examined the effect of a PC-enriched diet on gallstone incidence in mice susceptible to cholelithiasis. The result obtained showed that the feeding of a lithogenic (LG) diet for 4 weeks or 8 weeks resulted in cholesterol gallstone incidences of 47% and 89%, respectively. These gallstone incidences were either reduced or prevented when the LG diet was enriched with 2% or 6% PC, respectively. The cholesterol saturation index (CSI) was reduced only in mice fed with LG + 6% PC diet as compared with mice fed the LG diet alone. However, in all groups, the CSI was significantly higher than in mice fed Purina chow diet. The biliary anionic polypeptide fraction (APF) was significantly increased in mice fed the LG + 2% PC diet and was reduced in those fed with LG + 6% PC diet. In conclusion, prevention or delay of gallstone formation was not due to a consistent effect on biliary lipid composition, suggesting a direct effect of PC on cholesterol solubilization and/or the effect of an additional nonlipid biliary component such as APF.

Percutaneous ultrasound-guided cholecystocentesis in dogs

Percutaneous ultrasound-guided cholecystocentesis was performed on 13 healthy beagle dogs to determine whether percutaneous ultrasound-guided cholecystocentesis in the dog was a feasible and safe procedure. Clinical, laboratory and ultrasonographic examinations were done at 0 and 10 minutes, in the 2nd and 16th hour, and on the 7th day. They included a detailed physical examination of the mucous membranes, cardiorespiratory system and abdominal organs. Laboratory examinations of the blood consisted of a complete blood count, determination of packed cell volume (PCV), haemoglobin (Hb), total plasma protein (TPP), parameters of haemostasis including prothrombin time (PT), activated partial thromboplastin time (APTT), and enzyme activities reflecting hepatobiliary function, i.e. aspartate aminotransferase (AST), alanine aminotransferase (ALT), and gamma-glutamyltransferase (GGT). Ultrasonographic findings of the gallbladder (size, shape, wall, content) and appearance of the biliary tract and the surrounding cranial intraabdominal organs were also evaluated. Percutaneous ultrasound-guided cholecystocentesis was performed easily during the study, and dogs tolerated well the procedure performed without anaesthesia. All laboratory parameters of the blood remained within normal limits throughout the study. However, some follow-up values, i.e. PCV, TPP, APTT and ALT, demonstrated statistically significant differences when compared to baseline measurements, which might reflect the effect of 24-hour fasting before the experiment, as well as day-to-day metabolic fluctuations due to feeding and water supply during the study. There were no visible signs of bleeding from the liver, bile leakage from the gallbladder or accumulation of free peritoneal fluid during repeated ultrasonographic examinations. Percutaneous ultrasound-guided cholecystocentesis seems to be an important diagnostic procedure in canine gallbladder diseases and can be used safely and easily to gain gallbladder bile for diagnosis of bacterial cholecystitis or for investigating hepatobiliary function in the dog.

Biliary lipid composition in patients with cholesterol and pigment gallstones and gallstone-free subjects: deoxycholic acid does not contribute to formation of cholesterol gallstones

BACKGROUND

Four main disturbances have been attributed to cholesterol gallstone disease: hypersecretion of cholesterol from the liver with cholesterol supersaturation in bile; disturbed motility with defective absorption and secretion by the gallbladder; increased crystallisation of cholesterol in the gallbladder bile; and slow intestinal transit with increased amount of deoxycholic acid in the bile acid pool. We aimed to evaluate the biliary lipid composition in a large series of gallstone patients, with emphasis on the amount of deoxycholic acid and with respect to number of stones, compared to gallstone free subjects.

MATERIALS AND METHODS

Bile was sampled during operations through puncture of the gallbladder from 145 cholesterol gallstone patients, 23 patients with pigment stones and 87 gallstone free patients undergoing cholecystectomy. Biliary lipid composition, cholesterol saturation, bile acid composition, nucleation time and cholesterol crystals were analysed.

RESULTS

The patients with cholesterol gallstones showed higher molar percentage of cholesterol, lower total biliary lipid concentration, higher cholesterol saturation, shorter nucleation time and higher proportion of crystals in bile than the other groups. The nucleation time was significantly shorter in multiple cholesterol gallstone patients, but this was not due to higher cholesterol saturation. Male cholesterol gallstone patients showed higher cholesterol levels, lower total biliary lipid concentration, and higher cholesterol saturation in bile than female patients. There was no difference in biliary content of deoxycholic acid, but significantly lower content of cholic acid in gallstone patients compared to gallstone free patients.

CONCLUSIONS

We conclude that deoxycholic acid does not contribute to gallstone formation in cholesterol gallstone patients. The short nucleation time in patients with multiple cholesterol stones is not due to higher cholesterol saturation.

Biliary alpha 1-acid glycoprotein concentrations in gallstone-free controls and in patients with multiple or solitary cholesterol gallstones

We recently identified a promoting glycoprotein in the concanavalin A-bound fraction of gallbladder bile as a biliary form of alpha 1-glycoprotein (AAG). The concentration of biliary AAG appears to exert an important promoting effect on the speed of cholesterol nucleation in many patients with cholesterol gallstone disease. In the current study, we provide information about the biliary concentration of AAG as well as the amount and comparative potency of its subfractions in patients with and without cholesterol gallstone disease. The amount of total biliary AAG and the amounts of its different isoforms separated by concanavalin A affinity chromatography were measured by ELISA. Estimates of absolute concentrations of AAG for each sample were normalized to the sample total protein content to give relative AAG values. The promoting activity (potency) of immunopurified biliary AAG from gallstone patients and gallstone-free controls on cholesterol crystallization was compared by a crystal growth assay. The mean absolute concentration of AAG in gallstone-free controls was not significantly different from multiple stone patients. The relative concentration of AAG (micrograms per milligram total protein) was significantly increased in patients with multiple stones when compared to controls (P < 0.05), and both the absolute and relative concentrations of AAG (micrograms per milligram bile), were three- and to five fold higher in a number of these patients. The functional activity and distribution of AAG in different subfractions was similar in gallstone patients and gallstone-free controls. The relative concentration of biliary AAG is significantly greater in cholesterol gallstone patients with multiple stones than in gallstone-free controls.(ABSTRACT TRUNCATED AT 250 WORDS)