The value of bacterial metagenomic analysis in post-surgical examination of gallstones.

Gallstone disease is one of the most common causes of hospitalization for gastrointestinal diseases in the world. Recent studies have examined the presence of bacteria in the formation of stones. Our main goal was to determine the overall composition of gallstone microflora. Gallstones were obtained from 24 patients during laparoscopic cholecystectomy from which DNA were extracted. Composition of bacterial flora was evaluated on 16 s rDNA sequencing technique. In the vast majority of samples, bacteria were present, and four groups could be differentiated regarding the flora. Overall composition shows that 87% of the stones were cholesterol/mixed type of gallstone. Additionally, potentially harmful microorganisms (Streptococcus, Clostridium and Kocuria) that could cause post-surgery complications were identified in several patients. The obtained results indicate that this technique may be useful in analyzing the type of stones and in pinpointing the presence of pathogenic bacteria.