Trends in the epidemiology of intravascular device-associated bacteremia among French hematology patients: insights from the SPIADI prospective multicenter study, 2020-2024.

Abstract

Hematology patients require central venous catheters for cancer treatment and nutrition, which increases their risk of intravascular device-associated bacteremia. In the absence of recent data, we investigated intravascular device-associated bacteremia in this specific context. A three-month surveillance was conducted annually in 27 hematology wards, using a protocol derived from the HAI-Net ICU ECDC protocol (2020-2024). We analyzed the characteristics of infected patients, the sources and microorganisms of healthcare-associated bacteremias, and intravascular device-associated bacteremias (including catheter type: central venous catheter (CVC), implantable venous access device (IVAD), peripherally inserted central catheter (PICC), midline catheter (MID), and peripheral venous catheter (PVC)), the time between catheter insertion and infection onset, and bacteremia incidence rates per 1,000 patient-days. Over the five-year period, 1,835 patients experienced healthcare-associated bacteremia. No significant changes were observed in patient characteristics over the five-year period. The two primary sources of bacteremias were intravascular devices (n = 682; 37.2%) and the digestive tract (n = 467; 25.4%). The incidence rates of intravascular device-associated bacteremias acquired in the participating wards remained stable. Among the 682 intravascular device-associated bacteremias, 648 (95.0%) involved central venous catheters, primarily PICCs (42.8%), IVADs (25.6%), and CVCs (24.8%). The types of central venous catheters involved shifted over the five years, with a decrease in the proportion of CVCs (from 31.1% in 2020 to 16.8% in 2024) and, conversely, an increase in PICCs (from 35.2% in 2020 to 52.8% in 2024; p = 0.007). Among the microorganisms identified, coagulase-negative Staphylococci (n = 330; 40.6%) and Enterobacterales (21.9%) were the most common. Overall, 59 bacteremias (8.6%) were associated with multidrug-resistant organisms, with no significant trend over the study period. Of the 682 cases, 88.2% were nosocomial, while 11.8% were acquired following care provided in the community or at home. The two groups of bacteremias did not differ regarding microorganisms, and the increasing proportion of PICC-associated bacteremias was noted in both populations. In contrast, the proportion of bacteremias acquired in the community or at home significantly increased over the five-year period, starting in 2022 (6.9% of bacteremias in 2020, 6.5% in 2021, 11.8% in 2022, 16.4% in 2023, and 18.0% in 2024; p = 0.006), at the expense of nosocomial bacteremias. PICC-associated bacteremias were more common in patients with bacteremias acquired in the community or at home (57.7% vs. 40.3% for nosocomial bacteremias; p = 0.021). In addition, while most intravascular device-associated bacteremias involving central venous catheters were late-onset, with the time between catheter insertion and the onset of bacteremia exceeding 7 days in 84.8% of cases, nosocomial bacteremias were less frequently late-onset (82.8%) compared to those acquired outside healthcare institutions (97.3%; p = 0.002). The mechanisms behind the increase in the proportion of PICC-associated bacteremias occurring long after catheter placement and acquired in hematology wards or in the community/at home should be investigated. Given that Staphylococci, common components of the skin flora, are involved in approximately half of PICC-associated bacteremias, our findings raise concerns about adherence to aseptic techniques during line manipulations and catheter dressing changes, both in hematology wards and in community settings. Therefore, to improve the prevention of PICC-associated bacteremias in patients, our data should encourage local infection prevention teams to implement targeted educational programs to reinforce strict aseptic practices during catheter manipulations and dressing changes. As these procedures are increasingly performed outside hospitals, training should be extended beyond healthcare workers in hematology wards to include those providing home care.