Effects of Chemical Composition of Cholesterol and Pigment Stones on the Gallbladder Mucosa

Objective: To compare the effect of chemical composition of cholesterol and pigment stones on gallbladder mucosa. Study design & setting: This comparative cross-sectional study was conducted in the Department of Anatomy, BMSI, JPMC, Karachi, Pakistan, from April to September 2021. Methodology: Total n= 120 gallbladder specimens were collected after cholecystectomies in 10% formalin. Gross morphological features of gallbladder and stones were observed. Specimens were processed and 5µm sections from fundus, body & neck of gallbladder were stained and examined for microscopic changes. Chemical analysis of stones was carried out to differentiate between cholesterol & pigment stones. Results: We evaluated different histomorphological alterations in gallbladder with reference to both type of gallstones. Muscular wall thickness in pigment stone group was noted to be (143.89±78.66) and in cholesterol group (158.37±83.95). Both pigment and cholesterol stone showed increased tendency of muscular hypertrophy. Mucosal ulceration, chronic inflammatory cell infiltration, capillary congestion and hyperplasia (p-value: 0.04) were observed in both type of stones. Statistical analysis showed that large cholesterol stones produce significant histopathological changes (p-value: 0.004); greater the size of stone, more profound was the mucosal hyperplasia. Rokitansky-Ashcoff sinuses were predominant in gallbladders with cholesterol stone. Conclusion: Gallstones cause series of histopathological changes ranging from chronic cholecystitis to pre-malignant and malignant changes. Hyperplasia was observed to be more frequent with long standing, large cholesterol stones