Background: Pyogenic liver abscess is a life-threatening disease. Accurate data on incidence and prognosis are important, but scarce.
Aim: To examine changes in the incidence and 30-day mortality rate of patients with pyogenic liver abscess in Denmark.
Methods: Using nationwide administrative registers, we identified all patients diagnosed with pyogenic liver abscess in Denmark, 1977-2002, and their dates of death. We computed annual standardized incidence and 30-day mortality rates, and used Poisson regression to adjust gender-specific mortality rates for year-by-year differences in age at diagnosis.
Results: We identified 1448 patients with pyogenic liver abscess, of whom 54% were men. The crude incidence rate for the entire study period was 11.8 per 1,000,000 for men and 9.7 per 1,000,000 for women. Between 1977 and 2002, the incidence rate increased from 6 to 18 per 1,000,000 for men and from 8 to 12 per 1,000,000 for women. The cumulative 30-day mortality rate was 15% for men and 23% for women. The adjusted 30-day mortality rate decreased from 40% for men and 50% for women to around 10% for both genders.
Conclusions: In this large nationwide study spanning a 26-year period, we found an increasing incidence rate and a decreasing mortality rate of pyogenic liver abscess. We believe that these changes are primarily explained by more sensitive diagnostic tools.