The role of colonization with resistant Gram-negative bacteria in the treatment of febrile neutropenia after stem cell transplantation

Background

Febrile neutropenia (FN) is a common complication of stem cell transplantation.

Aim

To evaluate the frequency of sepsis in patients with FN colonized with resistant Gram-negative bacteria (extended-spectrum β-lactamase (ESBL)-positive, multidrug-resistant (MDR) Pseudomonas aeruginosa) and the choice of primary antibiotic in colonized patients.

Methods

This retrospective study analysed data from patients undergoing haematopoietic stem cell transplantation from January 2018 to September 2022. Data were extracted from the hospital information system.

Findings

Carbapenem as the primary antibiotic of choice was chosen in 10.9% of non-colonized +/–AmpC patients, 31.5% of ESBL⁺ patients, and 0% of MDR P. aeruginosa patients. Patients with FN and MDR P. aeruginosa colonization had a high prevalence of sepsis (namely 100%, P = 0.0197). The spectrum of sepsis appeared to be different, with Gram-negative bacilli predominating in the ESBL⁺ group (OR: 5.39; 95% CI: 1.55–18.76; P = 0.0123). Colonizer sepsis was present in 100% of sepsis with MDR P. aeruginosa colonization (P = 0.002), all in allogeneic transplantation (P = 0.0003), with a mortality rate of 33.3% (P = 0.0384). The incidence of sepsis in patients with ESBL⁺ colonization was 25.9% (P = 0.0197), with colonizer sepsis in 50% of sepsis cases (P = 0.0002), most in allogeneic transplantation (P = 0.0003).

Conclusion

The results show a significant risk of sepsis in FN with MDR P. aeruginosa colonization, a condition almost exclusively caused by the colonizer. At the same time, a higher risk of Gram-negative sepsis has been demonstrated in patients colonized with ESBL⁺ bacteria.