Cholesterol nucleation time measurement in nasobiliary or nasoduodenal bile. Comparison with surgical bile

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.

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.

Gallbladder motility and lithogenicity of bile in patients with choledocholithiasis after endoscopic sphincterotomy

BACKGROUND/AIMS

Ablation of the sphincter of Oddi has been shown to inhibit gallstone formation in the prairie dog model, probably by alleviating gallbladder bile stasis. The effect of endoscopic sphincterotomy (ES) on gallbladder emptying and lithogenicity of bile has not been studied adequately in humans. We, therefore, studied the changes in gallbladder emptying and lithogenicity of bile following ES in patients with choledocholithiasis and gallbladder in situ.

METHODS

Thirteen patients with choledocholithiasis with intact gallbladder underwent ES and common bile duct clearance. Eight patients had concomitant gallstones. Gallbladder emptying was studied by real time ultrasonography after stimulation by ceruletid infusion. Fasting gallbladder bile was collected during endoscopic retrograde cholangiography by placing a 7F or 8F catheter in the common bile duct and after ceruletid stimulation of gallbladder for bile microscopy and cholesterol nucleation time determination. Gallbladder emptying, nucleation time and bile microscopy were performed before ES and again between 4 and 8 weeks after ES after cholangiographic confirmation of clearance of common bile duct stones.

RESULTS

Fasting and residual gallbladder volumes decreased and ejection fraction increased significantly following ES, suggesting decreased stasis and improved emptying of gallbladder. Nucleation time was prolonged and cholesterol crystal index in bile decreased after ES, suggesting decreased lithogenicity. The decrease in gallbladder volumes and increase in ejection fraction after ES were observed in both groups of patients, with or without concomitant gallstones.

CONCLUSIONS

ES decreases the stasis of gallbladder bile, improves gallbladder emptying and decreases the lithogenicity of bile in patients with gallstone disease as reflected by prolongation in nucleation time. ES may find a role as an adjunct to oral bile acid therapy and extracorporeal shock wave lithotripsy in addition to a prophylactic role of preventing gallstone formation in high risk groups.

Ultrasound-guided percutaneous fine needle puncture of the gallbladder for studies of bile composition

Ultrasound-guided percutaneous fine needle puncture of the gallbladder (PFNP-GB) is invaluable for diagnostic and research purposes, but there are few reports about its safety. We therefore describe the efficacy and side-effects of 43 consecutive gallbladder punctures in 39 patients. PFNP-GB was successful in 40/43 (93%), but failed in three. Bile was completely aspirated in 28 of the 40 (70%) successful procedures. After 36 of the 43 punctures (84%), the patients remained asymptomatic, although on seven occasions (16%) the patients complained of right upper quadrant pain 0.5-12 h after the procedure. In six of these, the pain resolved in 2-24 h, although one developed a leucocytosis (22 x 10(9) 1(-1)). The seventh patient developed pyrexia and signs of generalized peritonism, which settled with conservative therapy. Ultrasonographic abnormalities of the gallbladder wall were seen in five of the seven symptomatic patients, consisting of: (i) an increase in the thickness of the gallbladder wall (n = 5) from less than 2 mm to 4-14 mm; (ii) peri-cholecystic collections (n = 2) measuring 5 and 11 mm in diameter; (iii) an intraluminal mucosal flap (n = 1); (iv) an intraluminal echogenic layer (n = 1); and (v) a 12 cm intraabdominal haematoma in the patient with generalized peritonism. Predictors of pain were: (i) the number of needle "passes" (3.7 +/- 0.8, range 2-8, in patients with pain vs 2.0 +/- 0.2, range 1-6, in pain-free patients, p < 0.02); (ii) the absence of gallbladder stones (p < 0.03); and (iii) incomplete aspiration of bile from the gallbladder (p < 0.02). PFNP-GB is an effective way of sampling fresh gallbladder bile, although there is a 16% risk of inducing pain and/or ultrasonographic changes in the gallbladder.