Gallstones containing bacteria are biofilms: bacterial slime production and ability to form pigment solids determines infection severity and bacteremia

• Published in: Journal of gastrointestinal surgery Vol. 11; no. 8; pp. 977 - 984
• Main Authors: Stewart, Lygia, Griffiss, J McLeod, Jarvis, Gary A, Way, Lawrence W
• Format: Journal Article
• Language: English
• Published: United States Springer Nature B.V 01.08.2007
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Bacteremia - etiology; Bacteria; Biofilms; Female; Gallstones; Gallstones - complications; Gallstones - microbiology; Humans; Infections; Male; Middle Aged; Pigments, Biological; Prospective Studies; Severity of Illness Index
• ISSN: 1091-255X; 1873-4626
• DOI: 10.1007/s11605-007-0168-1

Gallstone bacteria provide a reservoir for biliary infections. Slime production facilitates adherence, whereas beta-glucuronidase and phospholipase generate colonization surface. These factors facilitate gallstone formation, but their influence on infection severity is unknown. Two hundred ninety-two patients were studied. Gallstones, bile, and blood (as applicable) were cultured. Bacteria were tested for beta-glucuronidase/phospholipase production and quantitative slime production. Infection severity was correlated with bacterial factors. Bacteria were present in 43% of cases, 13% with bacteremia. Severe infections correlated directly with beta-glucuronidase/phospholipase (55% with vs 13% without, P < 0.0001), but inversely with slime production (55 vs 8%, slime <75 or >75, P = 0.008). Low slime production and beta-glucuronidase/phospholipase production were additive: Severe infections were present in 76% with both, but 10% with either or none (P < 0.0001). beta-Glucuronidase/phospholipase production facilitated bactibilia (86% with vs 62% without, P = 0.03). Slime production was 19 (+/-8) vs 50 (+/-10) for bacteria that did or did not cause bacteremia (P = 0.004). No bacteria with slime >75 demonstrated bacteremia. Bacteria-laden gallstones are biofilms whose characteristics influence illness severity. Factors creating colonization surface (beta-glucuronidase/phospholipase) facilitated bacteremia and severe infections; but abundant slime production, while facilitating colonization, inhibited detachment and cholangiovenous reflux. This shows how properties of the gallstone biofilm determine the severity of the associated illness.