Hematopoietic stem-cell transplantation in a zoo of multidrug-resistant organisms: Data from a cancer center in eastern India.

BACKGROUND: Infections by multidrug-resistant organisms (MDRO) are a major hurdle in hematopoietic stem-cell transplants (HSCTs). Conditioning regimens lead to mucosal barrier injury, which in-turn leads to transmigration of gut bacteria and sepsis. Pre-transplant stool and throat surveillance cultures can guide empirical antibiotic policy during the neutropenic period. In this paper, we document colonization with MDRO in pre-transplant surveillance cultures and the correlation with bloodstream infections in HSCT patients and analyze transplant outcomes with respect to these infections. METHODS: A single-center, retrospective study on HSCT was performed between January 2021 and December 2021. The incidence of bacterial infections, percentage of MDROs, correlation with pre-transplant stool/throat surveillance cultures, and their impact on overall 100-day and post-100-day to 6-month post-transplant survival were analyzed. RESULTS: Sixty-four patients were included in the study. Pre-transplant stool surveillance cultures were positive for MDRO in 85.9% of patients. Almost half (48.5%) of the isolates were positive for carbapenemase-producing genes (mainly New Delhi metallo-beta-lactamase-1 [NDM-1] and oxacillinase-48 [OXA-48]). Eighteen patients (18/64, 28%) had a positive blood culture for MDRO in the peri-engraftment neutropenic period. Correlation between surveillance and blood cultures was seen in 61% (11/18) of patients. All-cause mortality was 14.1% (9/64) and 25% (16/64) in patients at 100 days and 6 months post-HSCT, respectively. The 100-day and post-100-day all-cause mortality rates were higher in patients with Gram-negative MDRO bloodstream infections (p < .012 and <.008, respectively). CONCLUSION: MDRO infections can adversely affect HSCT outcomes. Pre-transplant stool and throat surveillance cultures may guide empirical antibiotic policy and lead to favorable transplant outcomes.

Multi-drug resistant (MDR) and extensively drug-resistant (XDR) bacteraemia rates among cancer patients in an oncology hospital in eastern India: an 11-year retrospective observational study.

Background: Trend analysis of bacteraemias caused by multi-drug resistant (MDR) and extensively drug resistant (XDR) bacteria helps to assess efficacy of infection prevention and control (IPC) practices. Data on the trends of MDR and XDR bacteraemias are lacking from cancer patients in India. Aims: To report antibiotic resistance rates over time in bacteraemias and to assess the effect of IPC practices where patient isolation facilities were limited on the rates and trends of MDR and XDR bacteraemias from a cancer centre in eastern India. Methods: A retrospective observational study was conducted in a specialist cancer hospital in India from 2011 to 2021. The study included both patients with haematological and solid organ malignancy. Data on blood cultures and surveillance culture samples were analysed. Blood cultures were processed using BACT/ALERT® (bioMérieux, Marcy-l'Étoile, France) and the identification and antibiotic susceptibilities of bacteria were performed using VITEK® 2 (bioMérieux, Marcy-l'Étoile, France). Surveillance cultures for MDR/XDR bacteria were performed on a subset of patients and processed based on a modified method described previously. Findings: 3rd-generation cephalosporin-resistant Gram negative bacilli were the commonest cause of MDR bacteraemia (57.6%) followed by carbapenem resistant organisms (CRO) (35.7%). Bacteraemias caused by vancomycin-resistant enterococci (VRE), meticillin-resistant Staphylococcus aureus (MRSA) and colistin-resistant Gram negative bacilli were responsible for 1.3%, 2.3% and 3.0% of laboratory confirmed bloodstream infections (BSI) respectively. The ranges of the rates of MDR/XDR BSI per 1000 in-patients during the study period were: MRSA (1-1.18), VRE (0-0.88), 3rd generation cephalosporin-resistant Gram negative bacilli (10.10-20.32), CRO (5.05-13.07) and colistin-resistant Gram negative bacilli (E. coli, Klebsiella, Pseudomonas aeruginosa, Acinetobacter spp (0-1.3). Surveillance cultures collected from a subset of patients showed ranges of MRSA detection in 0-2.11%, VRE in 1.67%-7.49%, 3rd generation cephalosporin-resistant Gram negative bacilli in 55%-89.91% and carbapenem resistant Gram negative bacilli in 18.33%-31.11% of patients. Conclusion: This is one of few studies providing trend data for MDR/XDR bacteraemia rates among cancer patients in India over a decade. In a high prevalence setting it was possible to keep the rates of MDR/XDR bacteraemia controlled with IPC strategies and without adequate isolation facilities. The results are of potential interest to policy makers, IPC specialists and clinicians.