Reversal of Antimicrobial Resistance (AMR) in Gram-Negative Pathogens in Hematology Oncology Patients

To analyse the trends in drug susceptibility patterns (DSP) of gram- negative bacilli (GNB) in setting of febrile neutropenia in hematology-oncology patients. This retrospective study (done from April 2019-April 2024) compares clinical (Charlson co-morbidity index [CCI], Sequential organ functional assessment [SOFA] score, Pitts bacteraemia score, and all cause 30 day mortality) parameters and trends in DSP of GNBs isolated from blood cultures of hematology-oncology patients. Various AMS activities, including restriction on use of high end antibiotics, cessation of antibiotics in patients with pre-neutropenic fever, involvement of an infectious diseases physician for management of multi-drug resistant (MDR) infections and improvement in diagnostics, among others, were done during this time period. In 535 patients, 601 different GNB bacteraemia episodes were identified. Time series analysis showed that carbapenem resistance in Klebsiella pneumoniae and Escherichia coli decreased from 90.3 to 48.1% (r = -0.961, p = 0.0006) & 54.5-27.7% (r = -0.882, p < 0.001) respectively, DTR (difficult to treat) rates in Pseudomonas aeroginosa fell from 83.3 to 10% (r = -0.716, p- 0.036). This study provides evidence that resistance in GNB can be curtailed by AMS activities even in highly vulnerable population like hematology-oncology.