Characteristics and Outcomes of Patients with Delftia acidovorans Infections: a Retrospective Cohort Study

Delftia acidovorans (D. acidovorans) is a Gram-negative bacteria and an uncommon cause of human infections. This retrospective cohort study investigated clinical and microbiological characteristics and outcomes of patients with D. acidovorans infections. We included patients with culture-confirmed D. acidovorans infections attending Rigshospitalet, during 2002-2020. Fifty-nine patients with a median interquartile ranges (IQR) age of 47 (15-67) years were included. Thirty-five (59%) were males, and 57 (97%) had at least one comorbidity, including 25 (42%) with solid or hematologic malignancies. Eight (14%) were admitted to ICU, and 15 (25%) died within 365 days after infection. Persistent infection was found in 4 (6.8%) patients, and 41 (70%) had polymicrobial cultures, mainly with Pseudomonas spp. and Stenotrophomonas maltophilia. More than 85% of the D. acidovorans isolates were susceptible to meropenem or ceftazidime. Although, 88% and 62% of the isolates were resistant to gentamicin and colistin, respectively. D. acidovorans infections mainly affect patients with preexisting comorbidities, including malignancies. In the first year, all-cause mortality is considerable, polymicrobial cultures are common, and meropenem or cephalosporins with antipseudomonal activity could be the antibiotics of choice. IMPORTANCE Delftia acidovorans (D. acidovorans) is a Gram-negative bacteria that can cause infection in immunocompetent and immunocompromised individuals. The current knowledge comes mainly from case reports and case series. In this retrospective cohort study, we found that D. acidovorans infections mainly affect male patients with preexisting comorbidities, including malignancies. Persistent infections were not common, and most of the patients had polymicrobial cultures, mainly with Pseudomonas spp. and Stenotrophomonas maltophilia. More than 85% of the D. acidovorans isolates were susceptible to meropenem or ceftazidime. In contrast, 88% and 62% of the isolates were resistant to gentamicin and colistin, respectively.