Bacteremia among kidney transplant recipients: a case-control study of risk factors and short-term outcomes

Kidney transplant recipients are highly susceptible to life-threatening infections, including bacteremia. To determine the risk factors for bacteremia within the first month after renal transplantation we performed a non-concurrent transplant population-based case-control study involving all 1,000 consecutively operated adult patients at Helsinki University Central Hospital in 1987-93. All patients with at least 1 positive blood culture within 31 d of transplantation were defined as cases. Control patients were drawn systematically from the transplant population with no positive blood cultures within the first 31 d post-transplant. The study included 35 cases and 123 controls. The overall rate of bacteremia in the population was 3.5%. The case patients were more likely to have been on haemodialysis prior to transplantation (71%, vs. 43%, p < 0.05) and to have experienced acute rejection (46% vs. 20%, p < 0.05) than the controls. Local infections (46% vs. 12%, p < 0.05) were also more common among case patients. In the crude analysis an additive interaction of acute rejection and haemodialysis was found, with a 10% rate of bacteremia occurring if both conditions were present. The mortality rate within 2 months of follow-up was higher among case patients than among controls (14%, vs. 1%, p < 0.05) and they also returned more often to dialysis (23% vs. 4%, p < 0.05). Bacteremia during the immediate postoperative period might still have severe outcomes measured as allograft and patient survival at 2 months post-transplant. Further evaluation will confirm whether a lower rate of bacteremia among kidney transplantation patients can be achieved if peritoneal dialysis is preferred to haemodialysis whenever possible.