Risk factors for mortality in febrile neutropenic patients treated with colistin.

This study aimed to investigate the prognostic factors of febrile neutropenic patients during colistin treatment. The indications for starting colistin treatment during febrile neutropenia (FN) episodes, nephrotoxicity, FN-related mortality rates, and the presence of isolated gram-negative bacteria in cultures were examined before initiating colistin treatment. This study included a total of 160 participants. The time from fever onset to colistin initiation was ≤ 5 days in 23 patients and > 5 days in 137 patients. When colistin treatment was initiated, 70 patients had sepsis or septic shock. There were 24% of patients had invasive pulmonary aspergillosis. Acute kidney injury occurred in 38 patients (24%). Klebsiella pneumoniae (41%), Acinetobacter baumannii (30%), and Escherichia coli (19%) were the most frequently isolated gram-negative bacteria. When these variables were included in the multivariate Cox regression model, the risk of mortality increased if colistin was started after the fifth day (hazard ratio [HR], 7.78; 95% confidence interval [95% CI], 1.89-31.95), patients had sepsis or septic shock (HR, 5.02; 95% CI, 2.03-12.37), patients had K. pneumoniae (HR, 3.06; 95% CI, 1.06-8.82) and A. baumannii infection (HR, 10.37; 95% CI, 2.91-36.92), and whether the patient had probable invasive pulmonary aspergillosis (HR, 6.51; 95% CI, 1.99-21.22). Culture-positive patients had a higher FN-related mortality rate than culture-negative patients (P = .04). In the presence of prognostic factors in our risk model, the early initiation of colistin therapy may reduce mortality.