INTRODUCTION
Febrile neutropenia is a well-known complication of chemotherapy and it is one of the most frequent oncologic emergencies treated by emergency physicians [1]. Neutropenia often develops due to both the toxic effect of chemotherapy and the spread of malign cells into the bone marrow preventing the growth of hematopoietic cells. Neutrophils play an important role against infectious agents thus neutropenic patients become more susceptible to infections [2]. Invasive infections and the conditions that cause sterile tissue damage may lead to an increase in the systemic inflammation together with inflammatory mediators and high fever. High fever in the patients with malignancy can result from the malignant cell lysis or mucosal damage induced by chemotherapy apart from the infections [3].
It is quite important to diagnose and treat serious infections resulting in morbidity and mortality in febrile neutropenia in the early phase. On the other hand, insufficient clinical and microbiological data in these patients cause serious problems in the diagnosis of the disease [4, 5]. It is hard to distinguish the infected patients from the non-infected ones through the use of simple inflammation parameters in febrile neutropenia, thus reliable biomarkers are necessary for the early prediction of the complications [3, 6]. Certain biological markers were suggested for this purpose and their relationship with the risk assessments was studied. The accuracy and predictive values of these markers were generally evaluated by small-scale, single-center clinical and laboratory studies and different results were obtained [7-9].
The mediators released due to oxidative stress are known to cause numerous systemic diseases accompanied by inflammation. Thiol/disulphide homeostasis parameters have been used for the detection of oxidative stress, and they have been measured in a one-sided way since 1979. Today, these parameters can be measured both separately and collectively by means of a new method developed by Erel and Neselioglu [10-13]. Moreover, PCT and CRP are the biochemical markers released in infection and inflammation [14, 15].
Researchers have tried to develop prognostic models for many years in order to classify patients with febrile neutropenia to foresee severe complications and risks that may occur. In 2000, the MASCC risk scoring index was published so as to make risk classification and especially to identify the ambulant patients at low risk [16, 17].
This study aims to determine whether it is beneficial to use thiol/disulphide homeostasis parameters, PCT and CRP together with the MASCC risk scoring system for the prediction of prognosis and mortality in the patients with febrile neutropenia presenting to the emergency department.