Functional Gallbladder Dyskinesia and Pathological Finding of Gallbladder Microlithiasis: Which Came First — The Chicken or the Egg?

Abstract

Introduction: Functional gallbladder (GB) dyskinesia is a debilitating disorder. We have previously shown that a significant number of subjects with chronic dyspepsia and a negative gastrointestinal (GI) work up had functional GB dyskinesia, which is characterized by a low GB ejection fraction (GBEF). Functional GB dyskinesia is thought to be due to metabolic disorders such as bile supersaturated with cholesterol or as a result of a primary motility disorder. However, the definitive etiology remains unclear. We examined the association of GB dyskinesia and blood dyscrasia, hypercholesterolemia, obesity, diabetes mellitus, and pathological findings of microlithiasis in subjects who underwent cholecystectomy. Methods: We retrospectively studied 129 subjects whose symptoms could not be explained by findings on abdominal ultrasound and computed tomography scan, upper and lower GI endoscopy. We excluded subjects with incomplete data, radiological findings of cholelithiasis/choledocholithiasis, previous sphincterotomy, any biliary surgery, and ongoing prokinetic medications. Pathology specimens were studied in those patients diagnosed with GB dyskinesia (low GBEF). Statistical analysis was performed using chi-square for categorical variables and t-test for continuous variables with age-, gender-, and ethnicity-adjusted odds ratios. Unconditional logistic regression model was used to estimate 95% confidence intervals (CI). SAS 9.3 software was used to perform the statistical analysis. Results are shown as mean (range). Results: One hundred twenty nine subjects were included. Seventy two percent (93/129) were female and fifty three percent (69/129) were African American. Mean age of the subjects was 54 (range 15-96). Fifty two percent (68/129) of subjects were diagnosed with GB dyskinesia. Of these, 24% (16/68) had chronic cholecystitis, and 3% (2/68) had microlithiasis found in pathological specimens. On multivariate analysis, the presence of blood dyscrasias (p=0.60), hypercholesterolemia (p=0.60), and diabetes mellitus (p=0.70) were not statistically significant. No correlation was found among age, gender, ethnicity, BMI, and GB dyskinesia. Conclusion: Metabolic disorders such as blood dyscrasia, hypercholesterolemia, and diabetes mellitus were not associated with GB dyskinesia. However, we found that subjects with GB dyskinesia had chronic cholecystitis and microlithiasis, which was not detected by imaging studies. Larger studies are warranted to validate these findings.