Proton pump inhibitor use significantly increases the risk of cryptogenic liver abscess: A population-based study

Background Proton pump inhibitors (PPIs) increase gastric pH and impair defence mechanisms against ingested pathogens, which may result in the overgrowth of virulent Klebsiella pneumoniae in the intestine and subsequent liver abscess. Aim We investigated the possible association between PPIs use and cryptogenic liver abscess in Taiwan. Methods We conducted a population-based case-control study using data from the National Health Insurance Research Database. A total of 958 adult cases of liver abscess and 3832 age-and sex-matched control patients were enrolled during 2000-2010. Conditional logistic regression was used to estimate the adjusted odds ratios (ORs) in patients using PPIs before cryptogenic liver abscess. Results The adjusted OR associating current use of PPIs (prescription within the past 30 days) with cryptogenic liver abscess was 4.7 [95% confidence interval (CI), 2.9-7.8], and recent use of PPIs (prescription within the past 31-90 days) with cryptogenic liver abscess was 2.9 (95% CI, 1.4-6.1). A dose-response relationship was apparent for cumulative dose of PPIs within 90 days. Adjusted OR was highest among the patients receiving PPIs more than 60 cumulative defined daily dose (OR = 6.5, 95% CI, 2.8-14.9). Conclusion Proton pump inhibitor therapy within the past 90 days was associated with an increased risk of cryptogenic liver abscess.