"Organ Donor With a Positive Blood Culture"

Shmuel Shoham, MD, Infectious Diseases

"A transplant cardiologist called me several weeks ago with a question. The previous night, they had transplanted a heart into a patient. Now, they have received word that a blood culture drawn from the donor had grown Enterobacter cloacae. How should the recipient, who was recovering from the transplant uneventfully, be managed? Had they known they known the blood culture results the previous night, should they still have transplanted the organ?

Let's tackle the second question first (should they still have transplanted the organ?). The issue of donor-derived infection is frequently on the mind of those involved in organ transplant and Primum non nocere (First, do no harm) is a major guide in decision making.

Potential donors are screened for a variety of blood and tissue borne pathogens. However, no test is perfect and there is no replacement for a good history. In their outstanding review on Donor-Derived Infections in Solid Organ Transplants, Grossi et al [American Journal of Transplantation 2009;(Supp 4):S19-26] suggest gathering the following data from the donor: history of previous infections, vaccinations, occupational exposures, travel history, contact with people with HIV, Hep B and C, tattooing, ear piercing or body piercing, illicit drug use, incarceration, sexual behavior, and contact with bats, stray dogs or rodents.

Some of the questions applicable to the recipient and medical team are:
a) how badly is the organ needed?
b) How rare is this particular organ?
c) How does the recipient feel about the risk?
D) What can be done to minimize the risk?

With regards to donor bacteremia, Freeman et al (Transplantation. 1999 Oct 27;68(8):1107-11.) found that 5.5 per cent of donors had + blood cultures, half of which were likely contaminants. Among the recipients of organs from the bacteremic donors, none were found to have evidence for transmission. The 30-day graft and patient survival for recipients of organs from bacteremic donors was not significantly different from recipients of organs from nonbacteremic donors. Similarly, Lumbreras et al (Clin Infect Dis. 2001 Sep 1;33(5):722-6.) evaluated the significance of donor blood culture results that were reported to be positive after transplantation. They found that 5 per cent of liver and heart donors had bacteremia at the time of organ procurement, but there were no documented instances of transmission of the isolated bacteria from the donor to the recipient. Len et al (Am J Transplant. 2008 Nov;8(11):2420-5) found non-viral infection in 8.8 per cent of donors and transmission to occur in approximately 2 per cent of recipients from those donors. However, when transmission did occur, the outcomes could be devastating (40 per cent mortality).

So as long as our patient was ok with the risk, I would have advocated transplantation of the heart, even if I had the information of the positive culture at the time of organ procurement.

Now back to the first question (How should the recipient be managed?). We started empiric anti-gram negative coverage and treated the recipient for about a week. The patient did fine, but I still do not know the answer as to how long he should have been treated."

Source:
http://boards.medscape.com