Chronic liver disease impairs bacterial clearance in a human model of induced bacteremia

Sepsis often causes impaired hepatic function. Patients with liver disease have an increased risk of bacteremia. This is thought to be secondary to impaired reticuloendothelial system function. However, this has not been demonstrated clinically. Since transient bacteremia occurs following toothbrushing, we hypothesized that subjects with cirrhosis would have impaired bacterial clearance following toothbrushing compared with subjects with pulmonary disease and healthy controls. After baseline blood was drawn, the subjects underwent a dental examination to determine plaque index and gingival index. Following toothbrushing, blood was drawn at 30 seconds, 5 minutes, and 15 minutes. Bacteremia was measured using quantitative real-time PCR with primers that amplify all known bacteria. We found greater than 75% incidence of bacteremia following toothbrushing. While control and pulmonary subjects were able to clear this bacteremia, subjects with cirrhosis had prolonged bacteremia. Baseline and peak bacterial load correlated with plaque index, suggesting that dental hygiene predicts the degree of bacteremia. However, only the severity of cirrhosis was predictive of bacterial clearance at 15 minutes, suggesting that liver function is important in clearing bacteremia. In this study, we demonstrate clinically that cirrhosis results in impaired bacterial clearance. This suggests that cirrhotic patients may be more susceptible to sepsis because of ineffective bacterial clearance.