Background: Bile analysis yields important information such as "biliary microlithiasis" and biliary tract colonization by microorganisms like Salmonella typhi or paratyphi, Escherichia coli, etc., which may progresses to cholelithiasis and have been found to have a role in the development of gallbladder cancer in India.
Aim: To perform microscopic, cytomorphological and microbiological examination of bile collected during endoscopic retrograde cholangiopancreatography in patients with benign and malignant lesions of the gallbladder.
Materials and methods: Bile was collected from 48 patients by a catheter inserted through the cystic duct during endoscopic retrograde cholangiopancreatography. Direct microscopy and grading of crystals was performed. Smears prepared from centrifuged deposits were stained with Giemsa, Papanicolaou stain and Gram's stain for cytological and microbiological examination. Special staining for Helicobacter pylori was performed using Loeffler's Methylene blue and Warthin Starry stain. The rest of the sample was used for culture and complete microbiological examination.
Results: Thirty-six patients had inflammatory lesions while 12 had malignant lesions. Crystals were observed in 93% of the cases, 13 (28.8%) had only cholesterol crystals, three (6.6%) had bilirubinate and 29 (64.4%) had both cholesterol and bilirubinate crystals. Smears from the centrifuged deposit mainly showed coccoid or cocobacillary bacteria on Gram's staining (81.3%). Five of 12 (41.6%) malignant cases showed epithelial atypia while none of the benign or inflammatory lesions showed such a change in hematoxylin and eosin and Pap-stained smears. Microbiologic analysis showed Staphylococcus aureus (14%), S. saprophyticus (5.5%), Peptococcus (5.5%), Peptostreptococcus (5.5%), Proteus mirabilis (5.5%), E. coli (17%), Enteorbacter cloacae (5.5%) and H. pylori (2.8%).
Conclusion: Complete microscopic and microbiological examination of bile directly obtained from the common bile duct during endoscopic retrograde cholangiopancreatography yielded good results as fresh samples could be analyzed. It may help in diagnosis of many gallbladder lesions in early stages, thereby reducing the morbidity and mortality.