S-613 Potential usefulness of direct rapid antibiotic susceptibility testing in blood culture = S-613 Potential usefulness of direct rapid antibiotic susceptibility testing in blood culture

다국어 초록 (Multilingual Abstract)

Background:?Antibiotic susceptibility testing (AST) is essential for choosing an accurate treatment of bacterial infections. Current AST requires at least 48h when a first blood culture (BC) is positive on direct smear examination (DSE). Thus, initial empirical antibiotic treatment is often inadequate, increasing rates of ineffective treatment or unnecessary broad spectrum antibiotic use. Direct rapid antibiotic susceptibility testing (dRAST) based on analyzing change of single bacterial cell under antibiotic condition detects antibiotic resistance in 4-6h after unveiling of DSE results and is expected to help more accurate selection of antibiotic.?Objective:?To assess accuracy of dRAST and evaluate its potential usefulness to improve selection of adequate antibiotic in clinical practice settings.?Material and Methods:?Among patients admitted to Seoul National University Hospital from June 2015 to December 2015, 141 patients with bacteremia were included for analysis. BC bottles from these patients were processed by both current AST method and dRAST. Prescribed antibiotics were recorded. In comparison with current AST, we evaluated whether the faster availability of dRAST results could have led to the initiation of optimal treatments without error. The efficacy of antibiotic treatment was classified as non-, sub-, optimal treatment according to antibiotic susceptibility to isolate.?Results:?Among 141 patients with bacteremia, 37 received non-optimal treatments and 4 had sub-optimal treatments after DSE results were reported. After the full results were known, 66% (27/41) changed non-, sub-optimal treatment into optimal treatment. For 98% (138/141), antibiotics prescribed supposedly in accordance with dRAST results were same with antibiotics prescribed in accordance with current methods. In at least 59% (24/41) patients, adequate treatment could have been done earlier with dRAST results. Unnecessary carbapenem treatments could have been avoided in 64% (9/14) of patients receiving carbapenem.?Conclusions: This study suggests that introduction of dRAST would increase treatment effectiveness and reduce unnecessary broad spectrum antibiotic use in early period of bacteremia.