The Microbiology of Laparoscopic Kidney Donation – A Baseline Study for Transvaginal Donor Nephrectomy

Calvin D Lyons, MD, Richard Link, MD, Osama Gaber, MD FACS, Vid Fikfak, MD, Barbara L Bass, MD FACS, Brian J Dunkin, MD FACS. The Methodist Institute for Technology Innovation and Education

Introduction: Kidney transplantation from a living donor is the treatment of choice for patients with end stage renal disease. Laparoscopic donor nephrectomy has become popular due to its decreased morbidity compared to the open technique. However, even a laparoscopic approach requires an extraction incision which causes pain and risks incisional hernia and wound infection. These unwanted complications have led surgeons to seek an alternative method of kidney extraction using the transvaginal route. Although promising, transvaginal extraction of the kidney raises concerns for bacterial contamination and the possibility of infection in the recipient. This study investigated the baseline contamination of living donor kidneys as part of a two arm study to determine the feasibility of transvaginal extraction of grafts for transplantation.

Methods: Eleven patients (9 female) at a single institution undergoing laparoscopic donor nephrectomy were enrolled. All laparoscopic donor nephrectomies were performed by one of two surgeons. Six were done using a periumbilical single port technique, and five with four 5mm ports and a Pfannenstiel extraction incision. Each incision was approximately 6cm in length and a specimen bag was used for all extractions. After the kidney was removed from the donor, the extraction bag was opened and a 2 x 2cm template used to obtain surface cultures prior to immersion in ice. The kidneys were then transferred to the transplant surgeons for flushing and immediate transplantation. Gram stain, culture, and sensitivity results were obtained.
Results: The average donor age was 41.7 years old. Procedure lengths were comparable in all cases as were the warm ischemia times for the graft, averaging 4 minutes 38 seconds. Four of 11 (36%) kidneys were colonized with aerobic or anaerobic bacteria. No kidney had more than one isolate. The isolated bacteria included non-hemolytic streptococcus, coagulase negative staphylococcus, enterococcus faecalis, and clostridium perfringens. Three positive cultures arose from the Pfannenstiel extraction and one from the single port technique. No recipient patient developed any infectious complications.
Conclusion: Conventional laparoscopic donor nephrectomies can result in surface contamination of the donated graft in over 1/3 of cases even without evidence of a break in sterile technique. This finding, combined with the low rate of graft infections, suggests that the presence of bacteria alone on the surface of a transplanted kidney does not lead to post transplant infections. This data establishes a microbiology baseline for the standard of care in laparoscopic donor nephrectomy that will be used in future feasibility studies for transvaginal donor nephrectomy.