Clinical and epidemiological characteristics of pyogenic liver abscess in people 65 years or older versus people under 65: a retrospective study

BACKGROUND: To analyse the clinical, epidemiological, microbiological and prognostic differences of pyogenic liver abscess (PLA) in older (≥ 65 years of age) versus younger patients (< 65 years). METHODS: Multicentre, retrospective cohort study in all patients with PLA admitted to two Spanish hospitals from January 2000 to January 2014. Cases were divided into two age groups (< 65 years and ≥65 years) for comparison of clinical, epidemiological and microbiological characteristics as well as treatment. RESULTS: Of 98 patients analysed, 40 patients were younger than 65, and 58 were aged 65 or older. Significant associations in the older group were found with female sex (adjusted odds ratio [ORa] 9.0; 95% CI 1.4, 56), non-cryptogenic origin (ORa 14.5; 95% CI 1.6, 129), absence of chronic liver disease (ORa 14; 95% CI 1.3, 155), Escherichia coli infection (ORa 7.7; 95% CI 1.03, 58), and incidence of complications (ORa 2.3; 95% CI 1.04, 5.4). Mortality was 8.2% overall, although all deaths occurred in the older group (8/58; 13.8%) (p = 0.02). DISCUSSION: Our results are in consonance with other published studies. Older patients with PLA tend to present more anomalies in the biliary tract (Kai et. al, World J Gastroenterol 18: 2948-295, 2012, Rahimian et. al, Clin Infect Dis 39:1654-9, 2004, Seeto, Medicine (Baltimore) 75:99-113, 1996, Kao et.al, Aliment Pharmacol Ther 36:467-76, 2012, Lai et. al, Gastroenterology 146:129-37, 2014), while younger patients are more often male and present more commonly with previous liver disease (especially related to alcohol) and cryptogenic PLA. CONCLUSION: In patients aged 65 or older, PLA was more common in women and in those with a history of biliary disease, and E. coli was the most frequent bacterium. Mortality was also higher in the older group.