The retrospective analysis of infection agents and antimicrobial therapies and treatment response in febrile neutropenic patients with hematologic malignancies at KTU Medical Faculty hematology unit between the dates 2015-2020

Aim: In this study, its aimed to investigate the causes of fever, to detect the causative microorganisms, to evaluate their response to antimicrobial treatments, examining treatment modifications and to improve local applications by comparing the effects of all these on morbidity and mortality. Materials and Methods: Patients with hematological malignancy and febrile neutropenia who were hospitalized in the Hematology Service of the Department of Internal Medicine of Karadeniz Technical University between 2015 and 2020 were evaluated. 197 patients and 541 attack of febrile neutropenia were analyzed. Demographic characteristics of patients, primary diagnosis, duration of neutropenia, empirical antibiotics initiation, antibiotic therapy modifications, G-CSF intake status, culture positive sites, positive causative factors, causes of fever (microbiologically documented fever, clinically documented fever, unexplained neutropenic fever), comorbidities and final discharge status were reviewed retrospectively. Results: 541 FEN attacks in 197 patients were analyzed. Mortality developed in 41 (7.57%) patients. There was a significant difference in mortality between MDE (microbiologically documented infection) and UNF (unexplained neutropenic fever), and between CDE (clinically documented infection) and UNF (p<0.001, p=0.007, respectively). The mean MASCC score was 21.14 ± 2.34. While there were 74 (13.7%) attacks with a MASCC score below 21, there were 467 attacks (86.3%) with a MASCC score of 21 and above. Culture positivity was detected in the blood in 146 (27%) and negative culture results were detected in 395 (73%) of the attacks. Gram (-) bacteria were encountered in 103 (70.5%), and Gram (+) bacteria were observed in 43 (29.5%) of the episodes in blood culture analysis. In terms of mortality, the difference was statistically insignificant. The most common Gram (-) agents were Escherichia coli and Klebsiella pneumoniae, and the most common Gram (+) agents were Streptococcus mitis and Enterococcus faecium in blood culture positive attacks. There were 72 multi-drug resistant bacteria growths. The most common MDRO (multidrug-rezistant organism) were Escherichia coli, Klebsiella pneumoniae and Pseudomonas Aeruginosa. The most common causes of fever were 118 (32.2%) bacteremia and 67 (18.3%) pneumonia. The cause of fever could not be determined in 174 attacks. In 290 of 541 febrile neutropenic attacks, treatment modifications were made in 3 steps. When the relationship between the necessity of antibiotic treatment modification and mortality was examined, the difference was statistically significant (p<0.001). Conclusion: The prognosis and higher mortality were related to the clinically or microbiologically documented infection, disease requiring empirical antibiotics other than regular protocol, need for treatment modification, patients with prolonged hospital admission, more than 7 days of neutropenia duration, number of days with fever, MASCC score below 21, the presence of a catheter, development of bacteremia, ARF (acute renal failure) development, high CRP and procalcitonin in the attack. Keywords: Febrile neutropenia, hematological malignancy, empirical antibiotic therapy