Common bile duct stones: a cause of chronic salmonellosis.

A chronic carrier state of Salmonella spp is present in 0.15% of the population, and is believed to be related to the presence of a diseased gallbladder. We present a patient with common bile duct (CBD) stones, whose bile cultures repeatedly indicated Salmonella typhi, despite an adequate course of antibiotic treatment. The carrier state was abolished after removal of the CBD stones 4 months later. The chronic carrier state may be related to biofilm formation on the surface of the CBD stones. The removal of the biliary stones, which are the most likely reservoir for Salmonella spp, may be a crucial step in eradication of the carrier state.