Evolution of Drug-resistant Acinetobacter baumannii After DCD Renal Transplantation

Area of Science:

• Infectious Diseases
• Transplantation Immunology
• Microbiology

Background:

• Infection post-renal transplantation poses significant risks, particularly from multidrug-resistant organisms.
• Acinetobacter baumannii is a major threat in transplant recipients, leading to high morbidity and mortality.
• Donation after cardiac death (DCD) transplants may carry unique infectious risks.

Purpose of the Study:

• To investigate an outbreak of Acinetobacter baumannii infections in DCD renal transplant recipients.
• To determine the transmission routes of Acinetobacter baumannii in a transplant setting.
• To evaluate the utility of integrated clinical and molecular methods for outbreak investigation.

Main Methods:

• Isolation and identification of Acinetobacter baumannii from donor preserved fluid and recipient draining fluid.
• Pulsed-field gel electrophoresis (PFGE) for initial DNA fingerprinting.
• Antimicrobial susceptibility testing (K-B diffusion and eTest).
• Whole-genome sequencing for detailed genetic analysis and phylogenetic relationships.

Main Results:

• Fourteen Acinetobacter baumannii isolates were recovered from DCD donor fluid and four from recipient draining fluid.
• PFGE indicated similar DNA patterns among isolates from the same hospital.
• Whole-genome sequencing confirmed transmission events, implicating donor-to-recipient spread and nosocomial transmission via medical procedures.
• Isolates 3R1 and 3R2 likely originated from the donor, while 4R1 was transmitted through medical manipulation.

Conclusions:

• Acinetobacter baumannii can be transmitted from DCD donors to recipients, posing a serious threat.
• Nosocomial transmission through medical interventions is a significant risk factor in transplant-associated outbreaks.
• Combining clinical data with molecular techniques is crucial for effective outbreak investigation and infection control in transplantation.