A comparison of bacteremic and non-bacteremic neutropenic patients treated at Hacettepe University Hospitals between 2018-2019 and an investigation of changing gram negative bacteria etiology, epidemiology and antibiotic resistance mechanisms between 2010-2019

Introduction: Number of patients with hematological disease and/or stem cell transplantation (HSCT) is increasing day by day. Bacteremia is important because of low risk of contamination and antibiogram study in this group of patients. Purpose of our research; to investigate factors affecting bacteremia development, mortality rates and mortality factors in febrile neutropenic patients with hematological disease and/or stem cell transplantation prospectively, and to determine the agent distribution and antibiotic susceptibility of microorganisms that reproduce from 2010 to the first 5 months of 2019. Method: Among adult patients with bacteremia due to gram negative (GN) bacilli and patients without bacteremia followed at Hacettepe University Adult and Oncology Hospitals between 01.01.2010-31.05.2019 was selected for study. The study was conducted retrospectively and prospectively observationally. In retrospective period (01.01.2010-28.02.2018), 211 bacteremic patients, in prospective period (01.03.2018-31.05.2019), 66 bacteremic and 132 non-bacteremic patients were collected. Bacteremic patients' GN bacteria reproduction, antibiotic susceptibility and resistance mechanisms of microorganisms were compared from blood culture from 2010 and to the first 5 months of 2019. Results: In patients with hematological disease and/or HSCT; male sex 2.77 times, radiotherapy before bacteremia, 5.16 times, steroid administration before bacteremia 3.47 times, concomitant infection with bacteremia 2.69 times, systolic blood pressure <90 mmHg 3.35 times, presence of septic shock 2.90 times, antibiotic use within 30 days 19.37 times, presence of intensive care hospitalization in the last 3 months 20.69 times, presence of colonization with resistant bacteria 2.82 times, 1 day increase of neutropenia before bacteremia 1.10 times, and 1 day prolongation of hospital stay 1.09 times increases risk of developing bacteremia. Presence of graft-versus-disease is 30 times, disease is resistant to treatment 18.17 times, 48 hours or longer urinary catheter presentation before bacteremia 24.23 times, concomitant infection with bacteremia 15.96 times, systolic blood pressure <90 mmHg before bacteremia 6.074 times, presence of septic shock 9.42 times, carbapenem-resistant GN bacteria growth 3.42 times, need of intensive care 90.25 times, intubation 59.5 times, administration of colistin in targeted therapy 8.4 times, and 1 day prolongation of hospital stay 0.98 times increases 30-day mortality in bacteremic patients after bacteriemia occurs. Chemotherapy (CT) given before bacteremia develops 20 times and appropriate empirical treatment 16.6 times reduces mortality. In non-bacteremic patients, disease is resistant to treatment 27.38 times, systolic blood pressure <90 mmHg 9.04 times, presence of septic shock 65 times, administration of colistin in targeted therapy 11.67 times, need for intensive care 72.67 times, intubation 39.64 times, continuation of neutropenia after fever (FEN) 1.046 times and use of antibiotics in the last 30 days 3.6 times increases mortality rates. Administration of CT before FEN 6.7 times and administration of colony stimulants 6.3 times to patients reduces mortality rates. When cultures over the ten-year period were evaluated, an increase trend was observed in multidrug-resistant bacteria (p = 0.03) and carbapenem-resistant Enterobacteriaceae (p = 0.02) over the years. There was no significant change in resistance to carbapenems (p=0.10), production of ESBLs (p=0.13) and ESBLs producing rates in Escherichia coli and Klebsiella pneumoniae (p=0.32). Conclusion: Many factors affecting bacteremia and mortality were found in our study. Of course, it is not possible to correct or prevent all of these factors. However, removal of unnecessary urinary and central catheters, avoiding inappropriate antibiotics, not being hospitalized for long, being careful in patients who have a high risk of developing neutropenia, starting appropriate prophylaxis at the right time, treating concomitant infections promptly, early identification of patients in need of intensive care, being careful of selection and application of invasive procedures, identification of patients at high risk for bacteremia, and appropriate empirical treatment in patients at risk of developing resistant bacteremia are general recommendations that can be applied include early identification of patients.