Aeromonas hydrophilia and Citrobacter braakii Septicemia from Cholecystitis/Cholangitis in a 90 Year Old Immigrant

Abstract

A 90 year old Korean lady presented to hospital with complaints of right upper quadrant pain accompanied by fever and vomiting of 2 days duration. Ultrasound examination identified a dilated common bile duct (CBD) with pericholecystic fluid. An endoscopic retrograde cholangiopancreaticogram revealed a distal ductal stone with purulent bilious fluid. Due to the presence of a papilla within a distal ductal diverticula a sphicterotomy was not performed. Blood cultures were positive for Aeromonas hydrophilia and Citrobacter braakii. Both organisms were sensitive to 3rd and 4th generation cephalosporins and pipericillin/tazobactam.She underwent an open cholecystectomy with CBD exploration, a choledocholithotomy and placement of a T-tube within the CBD. Her post op period was uneventful. Biopsy of the gall bladder revealed evidence of cholecystitis and abscess formation. We report this as the first case of cholecystitis in conjunction with both Aeromonas and Citrobacter. Both are gram negative bacilli, inhabitants of water and both are known to cause infections in immunocompromised hosts. Aeromonas species have been implicated in causing hepatobiliary infections with the largest series of patients having been reported from Asia where asymptomatic colonization rates may reach 30%. Aeromonas species are usually resistant to ampicillin and first generation cephalosporins. Citrobacter braakii refers to the genomospecies 6 of the Citrobacter freundii complex. There are few detailed studies of infections caused by this newly formed specific genetic species. To the best of our knowledge Citrbacter Braakii involvement in cholecystitis and or cholangitis has never been reported previously. Sensitivity studies and treatment with appropriate antibiotics should result in prompt recovery. Citrobacter are of low virulence and can exist in host populations for long periods. This leads us to believe it is possible that these two pathogens could have colonized our patient much earlier but caused sepsis in the setting of a CBD stone. 1. Aeromonas and possibly Citrobacter should be considered as pathogens in the setting of hepatobiliary infections in the south east asian immigrant populations. 2. Knowledge of pathogens that colonize the biliary tract is essential for treatment and management of sepsis.