Introduction: In the setting of Sepsis, Blood Culture is one of the important diagnostic tools in aiding a clinician to determine the offending pathogen. Following the Sepsis Bundle, Blood Culture is obtained at two sites before initiation of antibiotics. However, blood Cultures are one of the expensive tests wherein some clinicians find it unnecessary and costly. This study would provide more information regarding positive blood cultures among septic patients as a prognostic tool regarding the time to positivity. Reporting Time to Positivity would aid clinicians in the severity of the infection and could be used as a clinical predictor of mortality. This study investigated the optimal cutoff point of the time to positivity to predict mortality and the association between time to positivity of blood cultures with mortality among septic patients.

Methods: This was a single-center cross-sectional study with a retrospective chart review of septic patients with positive blood cultures. The optimal cutoff point of time to positivity was determined and associated with mortality.

Results: 405 adult in-patients with sepsis in Makati Medical Center from April 1, 2017, to April 30, 2018, were reviewed. The suggested optimal cutoff TTP is ?19.1 hours, with sensitivity 79.78%, specificity 28.48%, accuracy 39.75%, Youden's index 8.26%. The overall mortality rate is 21.98%. The mortality rate was higher in the TTP < 19.1 group at 23.91% compared to the >19.1 hours group. Predictors associated with mortality are age, liver comorbidity, genitourinary source of infection, and short TTP.

Conclusion: A short TTP was associated with higher mortality rates. TTP can be clinically used to predict poorer outcomes. Therefore, patients with a short TTP should be monitored more closely, and appropriate antibiotics should have been initiated.