Change of procalcitonin predicts clinical outcome of febrile episodes in patients with hematological malignancies

Background: Procalcitonin (PCT) was widely investigated in febrile neutropenia as an indirect marker of infection. Many institutions also use PCT as a tool to monitor the course of a febrile episode because increases in PCT values during the febrile episode were associated with development of complications. However, to date, no study systematically evaluated the accuracy of decreasing PCT values in predicting favorable outcomes of a febrile episode. The aim of this study was to evaluate the changes in PCT values after resolution of fever with regard to their predictive value of stable defervescence. Materials and methods: PCT was studied prospectively in 94 febrile episodes of 35 patients with hematological malignancies. Results: Sixty-seven episodes were associated with an increased level of PCT at the beginning. In these episodes, stable resolution of fever was significantly correlated with a decrease in PCT values. The best cut-off level to predict freedom from recurrence of fever for at least 5 days was <70% of the maximum PCT value on the second afebrile day. Out of 44 patient episodes with a subsequent decrease to <70%, only two patients had recurrent fever within the next 5 days, revealing a negative predictive value of 95%, p<0.001. Conclusion: Our study supports the value of PCT as a reliable tool to predict clinical outcome in febrile neutropenia.