Serum Lactate: A Predictor of Septic Shock in Childhood Cancers with Febrile Neutropenia.

Early recognition and management are the key elements to prevent febrile neutropenia associated mortality. The prospective observational study aimed to investigate prognostic accuracy of serum lactate to predict septic shock within 48 hours among hemodynamically stable children with febrile neutropenia. In all, 99 pediatric oncology patients who developed febrile neutropenia were enrolled in the study. Clinical information during 48 hours and serum lactate at the time of enrollment were analyzed. Among 99 participating patients, 10 developed septic shock and 4 of those expired. No significant difference was found of patients' baseline characteristics and basic laboratory parameters between patients with and without septic shock. Serum lactate was significantly elevated among patients developing septic shock (P-value < .001) and those who expired (P-value .002). Receiver operating characteristic (ROC) curve was created to identify the best cutoff value for initial serum lactate associated with the development of septic shock within 48 hours. Baseline serum lactate more than 2.5 mmol/L showed the largest area under the ROC curve to predict the septic shock development within 48 hours (ROC area, 0.90; 95% confidence interval [CI], 0.81-0.98), with sensitivity, specificity, negative predictive value, and accuracy of 80.0%, 92.1%, 97.6%, and 90.9%, respectively. Serum lactate level determined early at the time of febrile neutropenia was an effective surrogate marker for developing septic shock within 48 hours among hemodynamically stable, pediatric oncology patients. The level more than 2.5 mmol/L was the best threshold to start preemptive aggressive hemodynamic monitoring and prompt treatment to ensure adequate tissue perfusion.