Time to positivity as a novel predictor of outcome in intensive care unit patients with sepsis
© BioMed Central Ltd 2007
Published: 26 September 2007
Inadequate antibiotic therapy predicts poor outcome from sepsis, but there is no simple test of adequacy. We suggested that a time-to-positivity assay (Tpos) might act as a surrogate for antimicrobial activity and predict outcome from sepsis in the intensive care unit (ICU) . We are conducting a prospective clinical trial to test this hypothesis.
We studied 35 sequential ICU patients with onset of sepsis who had not had antibiotics for at least 3 days. Sepsis was defined as clinical evidence of infection plus at least three criteria for systemic inflammatory response syndrome. All patients received standard empiric therapy. Sera taken at 24 hours post antibiotics were inoculated into blood culture bottles containing standardised bacteria, incubated in an automated microbial detection system and the time to positivity noted. The primary clinical endpoint was days in the ICU.
These data show that some septic patients on standard antimicrobial regimens are receiving inadequate therapy. The Tpos is a new, simple assay that might be used effectively to monitor antibiotic use.