Eggerthella lenta Bloodstream Infections Are Associated With Increased Mortality Following Empiric Piperacillin-Tazobactam (TZP) Monotherapy: A Population-based Cohort Study

• Published in: Clinical infectious diseases Vol. 67; no. 2; pp. 221 - 228
• Main Authors: Ugarte-Torres, Alejandra, Gillrie, Mark R, Griener, Thomas P, Church, Deirdre L
• Format: Journal Article
• Language: English
• Published: US Oxford University Press 02.07.2018
• Subjects: Antibiotics; Appendicitis; Bacilli; Breakpoints; Cohort analysis; Confidence intervals; Gram-positive bacilli; Health risk assessment; Infections; Minimum inhibitory concentration; Mortality; Opportunist infection; Piperacillin; Piperacillin-tazobactam; Population studies; Population-based studies; Regression analysis; Risk analysis; Risk factors; Sepsis; Skin; Statistical analysis; Tazobactam; Tetragonal zirconia polycrystals; anaerobes; bloodstream infection; piperacillin-tazobactam; Eggerthella lenta
• ISSN: 1058-4838; 1537-6591
• DOI: 10.1093/cid/ciy057

Eggerthella lenta bloodstream infections are increasingly recognized, often caused by intraabdominal infections and associated with high mortality. Eggerthella lenta displays high minimal inhibitory concentrations to piperacillin-tazobactam (TZP), and empiric TZP monotherapy is a risk factor for 30-day mortality. Abstract Background Eggerthella lenta is a anaerobic gram-positive bacilli associated with polymicrobial intraabdominal infections. Recently, E. lenta was recognized as an important cause of anaerobic bloodstream infections (BSIs) associated with high mortality. Eggerthella lenta has been reported to have high minimal inhibitory concentrations (MICs) to piperacillin-tazobactam (TZP), a broad-spectrum antibiotic with anaerobic coverage commonly used in multiple centers for empiric treatment of abdominal sepsis. Methods We describe a retrospective population-based analysis of invasive E. lenta infections from 2009 through 2015. A logistic regression analysis for 30-day mortality risk factors was conducted. Results We identified 107 E. lenta infections, 95 (89%) were BSIs, 11 (10%) skin and soft tissue infections, and 1 intraabdominal abscess. Polymicrobial infections were found in 40%; 72% of isolates were from a gastrointestinal source, most commonly appendicitis (33%) of which two-thirds were perforated. TZP MIC50 and MIC90 for E. lenta isolates were 32 μg/mL and 64 μg/mL, respectively. The overall 30-day mortality for BSI was 23% and was independently associated with empiric TZP monotherapy (odds ratio [OR], 4.4; 95% confidence interval [CI], 1.2-16; P = .02) and intensive care unit stay (OR, 6.2; 95% CI, 1.4-27.3; P = .01). Thirty-day mortality rates were significantly influenced by the use of different TZP MIC breakpoints. Conclusions Our results demonstrate the increased recognition of E. lenta as an anaerobic opportunistic pathogen and highlight the need for improved empiric antimicrobial guidelines and TZP MIC breakpoints with better correlation to clinical outcomes to guide appropriate management of invasive E. lenta infections.