Gallstones in chronic spinal cord injury: is impaired gallbladder emptying a risk factor?

OBJECTIVE

To confirm that spinal cord injured persons are susceptible to gallstones and to evaluate the role of gallbladder stasis as a risk factor.

STUDY DESIGN

Twenty-nine subjects with chronic spinal cord injury underwent fasting ultrasonography to determine the incidence of gallstones and to quantitate gallbladder emptying response to a 20g fat liquid meal. Gallbladder emptying fraction was compared to that of healthy subjects studied concurrently.

RESULTS

Gallstones or sludge were found in 6 spinal cord injured men, a minimal prevalence of 21%. Four additional subjects had prior cholecystectomy for stones, giving a potential maximal prevalence of 30%. Four of the 6 subjects had gallstone risk factors of diabetes, obesity, and/or family history. Gallbladder stasis was not apparent in chronic spinal cord injured subjects. Only 5 subjects had poor gallbladder emptying, and 4 of them had diabetes and/or obesity.

CONCLUSIONS

The study confirms an increased prevalence of gallstones after spinal cord injury. However, gallbladder stasis did not appear to be etiologic, and most gallstones were associated with conventional risk factors. The results do not support a general policy of gallstone screening or prophylactic therapy after spinal cord injury.

The role of gallbladder emptying in gallstone formation during diet-induced rapid weight loss

Obese persons are at risk for cholesterol gallstones because their bile is saturated with cholesterol. The risk increases during rapid weight loss by means of certain very-low-calorie diets or gastric bypass surgery. Gallstone risk factors during rapid weight loss include increased bile cholesterol saturation index and gallbladder stasis. Obese subjects were randomized to one of two low-calorie liquid diets for rapid weight loss: a 520-kcal diet with less than 2 g fat/d, and a 900-kcal diet with 30 g fat/d (including one 10-g fat meal to stimulate maximal gallbladder emptying). Bile and blood lipids, saturation index, leukocyte 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase activity, and ultrasonographic gallbladder emptying were measured repeatedly during dietary treatment. Both diets produced comparable weight loss of 22%. Bile cholesterol saturation index increased during both diets (26%), but fell to 15% below prediet level after weight loss. Compared with subjects' maximal gallbladder emptying fraction of 66%, the 520-kcal diet provided poor gallbladder emptying (35%), whereas the 10-g fat meal of the 900-kcal diet provided maximal emptying. Gallstones developed in four of six 520-kcal subjects and none of seven 900-kcal subjects (P = .021), an unanticipated difference that resulted in premature study termination for ethical reasons. Blood lipids and HMG CoA reductase activity in mononuclear leukocytes fell at week 8 during both diets, but recovered while weight was still being lost. The findings suggest that gallstone risk during rapid weight loss may be reduced by maintenance of gallbladder emptying with a small amount of dietary fat. Ultimately, weight loss reduced bile cholesterol saturation and improved highdensity lipoprotein (HDL) levels.

A randomized blinded comparison of omeprazole and ranitidine in the treatment of chronic esophageal stricture secondary to acid peptic esophagitis

BACKGROUND

Esophageal strictures due to gastroesophageal reflux disease are often resistant to medical therapy and require repeated dilation procedures. Our aim was to compare the efficacy of therapy with omeprazole (20 mg/day) to ranitidine (150 mg twice daily) in the treatment of chronic esophageal strictures.

METHODS

Thirty-three patients with chronic esophageal stricture disease (mean length of prior treatment, 50.9 months) were entered into a randomized blinded trial. The majority (88%) of the patients had received multiple prior esophageal dilations (mean, 7.9 per patient). Endoscopy and barium esophagograms were performed initially and at the end of 10 months. Symptoms were considered every 2 months and dilations performed as needed. The patient groups were equivalent.

RESULTS

One patient in each group was subsequently lost to follow-up. No significant differences were seen in symptom improvement or need of dilation. At the final endoscopy, 8 of 17 (47%) patients receiving ranitidine had residual erosions or ulceration, compared with 1 of 14 (7%) patients receiving omeprazole (p >0.2). All patients receiving ranitidine had persistent strictures, whereas 8 of 14 (57.1%) patients receiving omeprazole had radiographic and endoscopic resolution of their strictures (p <0.004).

CONCLUSION

These data further emphasize the need for vigorously treating esophagitis in patients with acid peptic strictures.

Variability in measurement of abdominal aortic aneurysms. Abdominal Aortic Aneurysm Detection and Management Veterans Administration Cooperative Study Group

PURPOSE

The purpose of this study was to report interobserver and intraobserver variability of computed tomography (CT) measurements of abdominal aortic aneurysm (AAA) diameter and agreement between CT and ultrasonography observed in the course of a large, multicenter, randomized trial on the management of small AAAs.

METHODS

CT measurements of AAA diameter from participating centers were compared with measurements made from the same scan by a central laboratory. Blinded central remeasurement of a randomly selected subset of these CT scans was used to assess intraobserver variability. Agreement between AAA measurements by CT and ultrasonography done within 30 days of each other was also assessed.

RESULTS

For interobserver pairs of local and central CT measurements of AAA diameter (n = 806), the difference was 0.2 cm or less in 65% of pairs, but 17% differed by at least 0.5 cm. For intraobserver pairs of central CT remeasurements (n = 70), 90% differed by 0.2 cm or less, 70% were within 0.1 cm, and only one differed by 0.5 cm. Of 258 ultrasound-measured and central CT pairs, the difference was 0.2 cm or less in 44% and at least 0.5 cm in 33%. Ultrasound measurements were smaller than central CT measurements by an average of 0.27 cm (p < 0.0001). Local CT and ultrasound measurements showed a marked preference for recording by half centimeter.

CONCLUSIONS

A high degree of precision is possible in CT measurement of AAA diameter, but this precision may not be obtained in practice because of differences in measurement techniques. Differences between imaging modalities increase variability further. Variations in AAA measurement of 0.5 cm or more are not uncommon, and this should be taken into account in management decisions. Efforts to reduce variation in measurement are warranted and might include (1) seeking agreement between surgeons and radiologists on a precise definition of AAA diameter, (2) limiting the number of radiologists who measure AAAs, and (3) use of calipers and magnifying glass for CT measurements.

Gallbladder emptying stimuli in obese and normal-weight subjects

Gallbladder stasis may be an important factor in the pathogenesis of cholesterol-gallstone formation in some individuals. We investigated gallbladder function in a group of nondieting, gallstone-free, healthy subjects with normal (22 +/- 1 kg/m2) and high (36 +/- 1 kg/m2) body mass indexes. Fasting gallbladder volume (28.2 +/- 4.4 ml) and residual volume after maximal emptying (8.4 +/- 2.3 ml) in high-body-mass index subjects were not significantly different from those of normal-body-mass index subjects (20.5 +/- 2.5 ml and 4.2 +/- 1.3 ml, respectively). The percentage of gallbladder emptying (71% +/- 5%) and the rate of gallbladder emptying (-1.9 +/- 0.3 x 10(-2) min-1) in high-body-mass index subjects in response to a maximal emptying stimulus was similar to the percentage of emptying (78% +/- 6%) and rate of emptying (-2.3 +/- 0.6 x 10(-2) min-1) in normal-body-mass index subjects. A liquid meal containing less than 1 gm fat, 14 gm protein and 6 gm carbohydrate resulted in both a decreased rate of gallbladder emptying and an increased residual gallbladder emptying and an increased residual gallbladder volume in both groups. The addition of 10 or 20 gm (but not 4 gm) of fat to the liquid meal restored gallbladder emptying to the maximal-stimulus level. These results demonstrate that gallbladder emptying in response to a single liquid meal stimulus is not altered in obesity and that dose-response relationships to fat are similar in obese and normal-weight individuals.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy of chenodeoxycholic acid and ursodeoxycholic acid for lowering cholesterol saturation index of gallbladder in patients with a sphincterotomy

After endoscopic retrograde sphincterotomy, patients with an intact gallbladder are at risk for developing symptoms or complications of gallbladder stones. Medical dissolution of such stones would be desirable, especially in elderly patients with an increased surgical risk. However, sphincterotomy alters emptying dynamics of the gallbladder and markedly reduces bile salt pool size, effects that may alter response to chenodeoxycholic acid or ursodeoxycholic acid treatment. Studying two groups of 5 patients with an intact gallbladder after endoscopic retrograde sphincterotomy, we found that 15 mg/kg.day of chenodeoxycholic acid increased the mean (+/- SEM) biliary percentage of chenodeoxycholic acid from 35.5% +/- 4.0% to 88.8% +/- 1.9% (p less than 0.01) and decreased the mean saturation index of gallbladder bile from 1.02 +/- 0.22 to 0.55 +/- 0.08 (p less than 0.05). Ursodeoxycholic acid (10 mg/kg.day) increased the mean biliary percentage of ursodeoxycholic acid from 5.6% +/- 1.5% to 44.7% +/- 5.8% (p less than 0.01) and decreased the mean saturation index of gallbladder bile from 1.04 +/- 0.25 to 0.57 +/- 0.03 (p less than 0.05). A long-term trial of bile acid treatment in sphincterotomy patients with stones in an intact gallbladder is needed.

Partial biliary obstruction caused by chronic pancreatitis. An appraisal of indications for surgical biliary drainage

This paper presents a retrospective review of 38 patients with intrapancreatic bile duct strictures secondary to chronic alcoholic pancreatitis. The strictures were identified by endoscopic retrograde cholangiopancreatography (ERCP). All patients with pancreatic cancer and gallstone pancreatitis were excluded. The mean alkaline phosphatase and total bilirubin values were 344 +/- 57 IU/dl and 4.4 +/- 0.7 mg/dl, respectively. The mean stricture length was 3.9 +/- 0.5 cm, and the mean common bile duct (CBD) diameter was 1.8 +/- 0.2 cm. The degree of bilirubin and alkaline phosphatase elevation did not correlate with stricture length or the severity of bile duct dilatation. Eighteen of the 38 patients received surgical biliary drainage (BD) as part of their initial therapy, and 20 patients did not. Liver function tests, intrapancreatic stricture length, and the degree of proximal CBD dilation were comparable in these two groups. Patients not undergoing BD did well clinically as only one patient required BD over an average follow-up period of 3.8 years. In conclusion, bypass of these strictures is usually unnecessary, and most patients may be safely treated without operation.

Clinical and endoscopic findings in patients early in the course of clostridium difficile-associated pseudomembranous colitis

Endoscopic and clinical features are reported for 39 patients detected early in the course of pseudomembranous colitis. Disease was detected early by virtue of careful surveillance in patients in whom diarrhea developed. Early proctosigmoidoscopic findings in pseudomembranous colitis are illustrated. Clinical presentation includes development of fever, leukocytosis, abdominal pain, and even an ileus picture on radiography in addition to diarrhea.

Postsplenectomy gastric deformity

Mass- or polyplike defects of the gastric fundus were found on upper gastrointestinal examination in five patients, representing 7% of those who had undergone splenectomy. In four cases, the splenectomies were performed 1--5 months earlier, and, in one, the splenectomy was performed 10 years before. Dense adhesions were the cause of the defects in two patients. Plication deformity was thought to be a possible cause in the others. Recognition of the nonneoplastic nature of such defects is important in preventing unnecessary surgery. Computed tomography and endoscopy may be helpful in confirming the diagnosis.

Is intravenous cholangiography still useful?

A retrospective study was performed to determine the usefulness of the intravenous cholangiogram for evaluation of common bile duct disease. Using interpretations obtained by chart review, 128 intravenous cholangiograms were categorized according to common bile duct visualization. Fifty-five percent of the studies were considered technically adequate for interpretation, while 23% and 22% were suboptimal and nondiagnostic, respectively. The intravenous cholangiogram diagnoses were verified when possible by comparison with the findings of: (a) endoscopic retrograde cholangiography, (b) operative cholangiography, (c) choledochotomy, or (d) autopsy. In verified studies of adequate intravenous cholangiograms, the diagnostic error rate was 40%, largely owing to missed stones. We conclude that the intravenous cholangiogram is usually unreliable for biliary tract evaluation, and should be replaced by alternative studies such as endoscopic or transhepatic cholangiography.

A comparison of upper gastrointestinal endoscopy and radiography

One hundred symptomatic patients were evaluated independently with upper gastrointestinal radiography and fiberoptic endoscopy, and the results were compared. Of the two endoscopists sequentially examining the same patient, one was informed of available clinical and radiographic details and the other was not. Knowledge of the x-ray examination by the informed endoscopist did not improve his accuracy. Each endoscopist made four errors of interpretation. The endoscopic and x-ray findings agreed in 46 of the 100 patients, most often (68%) in esophagus, least often (29%) in the stomach and half the time (45%) in the duodenum. Ulcer craters seen endoscopically were detected radiographically in 36% of patients. We conclude that: 1) knowledge of results of prior upper gastrointestinal radiography did not alter endoscopic results; 2) experienced endoscopists are accurate but make mistakes; and 3) endoscopic findings would have been unaltered had radiography not been performed.

Significance of the nonopacified gallbladder in endoscopic retrograde cholangiography

Failure to visualize the cystic duct and gallbladder during endoscopic retrograde cholangiography, while obtaining satisfactory opacification of the rest of the biliary system, is a radiographic sign of undetermined meaning. The diagnostic implication of this finding was analyzed in 63 patients with pathologically proven diagnoses. One patient was normal at surgery. Three groups of abnormal patients had: (1) obstructing lesions of the distal common bile duct (35 patients); (2) primary lesions of the cystic duct or gallbladder (19 patients); or (3) obstructing lesions about the common hepatic/cystic duct junction (8 patients). The results indicate that obstructing lesions of the distal common bile duct may cause stasis of bile within the biliary system, increased biliary pressure, and sludge formation that prevent the flow of contrast material through the cystic duct and into the gallbladder, which can cause nonopacification. If the extrahepatic biliary system is of normal caliber without evidence of an obstructing process, nonfilling of the cystic duct and gallbladder is highly predictive of pathology.

Cholangiographic abnormalities in patients with inflammatory bowel disease

Twenty patients with inflammatory bowel disease, abnormal liver function tests and abnormal endoscopic retrograde cholangiograms were found to have a spectrum of abnormalities affecting the intra- and extrahepatic biliary trees. The intrahepatic systems were abnormal in all patients and demonstrated ductal stenosis, ectasia, decreased arborization and major duct obstruction. The extrahepatic systems were abnormal in 75 percent of cases with stenosis, diverticula formation and mural irregularity being the most frequent abnormalities. The value of endoscopic retrograde cholangiography in this patient group is to exclude extrahepatic obstruction, establish a nonoperative diagnosis, and assist in determining the method of treatment.

Endoscopic retrograde intrahepatic cholangiogram: radiographic findings in intrahepatic disease

Endoscopic retrograde intrahepatic cholangiograms were evaluated in 107 patients and correlated with intrahepatic diagnoses determined by liver biopsy. Included were normal livers (six), cirrhosis (38) portal fibrosis (14), cholangitis (22), metastases (11), and miscellaneous diagnoses (16). Results suggest that differentiation of the normal from the abnormal intrahepatic biliary system using the endoscopic retrograde intrahepatic cholangiogram is possible, and that certain patterns of abnormality prevail within given disease categories. The cholangiogram in cirrhosis is marked by ductular stenosis, diminished arborization, tortuosity, and approximation of the intrahepatic ducts. Sclerosing cholangitis demonstrates focal stenoses with concomitant ectasias and frequent similar involvement of the extrahepatic system. Chronic cholangitis and portal fibrosis are frequently associated with extrahepatic obstructing lesions and increased intrahepatic ductal caliber, but demonstrate no distinguishing intrahepatic characteristics. Intrahepatic metastases, polycystic liver disease, and primary hepatic neoplasm produce mass effects consisting of ductal displacement, narrowing, and obstruction. The potential of endoscopic retrograde intrahepatic cholangiography in evaluating the intraheptic biliary tree is significant; specifically in separating normal from abnormal, in distinguishing between intrahepatic processes, and as an adjunct to liver biopsy in determining the extent and location of intrahepatic abnormalities.