Introduction: Although rarely reported, donor-transmitted bacterial infection is a serious complication after heart transplantation. Due to organ shortage, nonbacteremic localized infections are not considered an obstacle for transplantation in many centers.Here a recipient who was followed up with donor-derived extended spectrum resistant ( XDR) Klebsiella pneumonia bacteremia after heart transplantation is presented
Case: A 50-year-old man who had been followed up with a left ventricular assist device (LVAD) since 2020 for dilated cardiomyopathy was hospitalized on 28/12/23 due to possible infective endocarditis caused by Staphylococcus haemolyticus. While the patient was on cefazolin treatment, cadaveric heart transplantation was performed on 18/01/24.
The donor was a 48-year-old man with no known comorbidities. He was followed up in the intensive cate unit ( ICU) of another hospital in the same city for 17 days  because of traumatic subarachnoid hemorrhage and he was intubated. .On the organ  precurement day he was recieving piperacillin tazobactam treatment for 5 days empirically because of  subfebrile fever  and CRP elevation (11mg/L to 88mg/L)  but blood, urine and tracheal aspirate cultures taken from him were negative during this period.
The transplantation was performed  succesfully but on the 5th day of transplantation, the recipient had fever and  XDR Klebsiella pneumoniae was isolated from blood cultures. He recieved colistin and meropenem. It was learned that  XDR Klebsiella pneumoniae  was isolated  from  blood cultures  takenfrom donor before  organ procurement. Simultaneus bacteremia was detected in the donor’s other organ recipients ( two kidneys and one liver).
Recipent  gave response to antibacterial treatment  and blood cultures taken on 04/02/24 revealed  no growth.  It’s also learned that the other recipients recovered. 
Conclusion: Pretransplant screening of donors are essential for organ transplantation. On the other hand it is not possible to  rule out bacterial infections especially from deceased  donors who are treated in ICU. Here a serious bacterial infection transmitted to 4 recipients from a donor with an undocumented infection is presented. It is intended to emphasize that donor candidate receiving ICU treatment should be evaluated more detailed.