The most important issue in LDLT is donor safety, and the ability to donate the appropriate graft size for the recipient. The risks of mortality and morbidity with live donor right hepatectomy have been previously estimated as 0.4% and 35%, respectively (
4). Only one-third of potential donors are accepted as candidates for the procedure (
5). Some centers have used a 4-phase approach to assess live liver donors (
6,
7), while another center used a 5-step evaluation protocol. In this study, we tried to determine contraindications to donation early before conducting expensive and invasive tests. Phase 1 represents the highest number of rejected donors before proceeding to the final phase, which involves anatomical and pathological assessment of the graft. This evaluation protocol is close to the protocols used at Cairo University, Kyoto University in Japan (
5), and the University of Heidelberg in Germany (
8).
In a previous series, 68.2% of potential donors were excluded early, and only 23% of those who had complete work-up underwent the operation. Both donor and recipient reasons for rejection were included (
9). However, our study was mainly concerned with reasons for donor rejection. In addition, our study is unique, because it showed that the main reason for rejection was Factor V Leiden mutation. In another study, 33% of potential donors were rejected (
10). In a series of patients, 11% of potential donors were not accepted due to fatty liver and abnormal liver enzymes, which is in agreement with our findings (eight with fatty liver, and nine with abnormal transaminases of 126 donors) (
11). Renz and Roberts accepted only 13% of potential donors, with 23% rejected for medical reasons, and 20% rejected for psychosocial reasons (
12). In our study, 51% of donors were rejected early. The remaining 49% proceeded to the third phase, and 14.6% were excluded at this phase. In another series, of 126 donors, 69% were disqualified due to incompatible blood type, steatosis with low graft-to-recipient weight ratio, and positive results for hepatitis serology (
6).
Although the donor rejection percentage (65.6%) in our study was similar, ABO-incompatible potential donors were not enrolled in our study. Nevertheless, Factor V Leiden mutation (23%) was the most significant cause of rejection in our study, which is incomparable to any other series, and represents a new finding requiring broad investigation. Factor V Leiden mutation is the most common etiological factor in Egyptian patients with Budd-Chiari Syndrome (
13). Our data also showed a higher percentage of positive results for hepatitis serology compared to the previous studies (7.9% HCV and 11.9% HBcAb), which is explained by a higher prevalence of viral hepatitis in Egypt than other countries. We also had more potential donors rejected for drug abuse (12.7%), fewer donors with steatosis (7.9%), and a similar proportion of donors with small-for-size livers (4.8%) compared to the study mentioned above. Valentin-Gamazo and colleagues found only 14% of potential donors to be suitable, and excluded 67% with positive results for hepatitis markers or blood incompatibility (
14). In another study, 56.5% of potential donors were excluded. Positive results for hepatitis serology and ABO incompatibility were the main contraindications to donation (
15). Pascher et al. reported that 39.9% of potential donors were declined because of blood group incompatibility or obvious contraindications, 18% had steatosis of more than 10%, and 7.9% showed psychological contraindications (
16). In our center, we accepted HBcAb-positive donors provided for a recipient who was also HBcAb-positive. In a 2005 study by Nadalin et al. 108 of 730 donors (15%) were considered suitable. Liver biopsy revealed a positive finding in 31 of 144 candidates, including 21 cases of steatosis, and 10 cases of non-steatotic hepatopathy (
17). In our study, 94 potential donors proceeded to phase 3 and underwent liver biopsies. Eleven (8.7 %) subjects had positive pathological findings and were rejected, 9 (7.1 %) due to steatosis of more than 15%, and 2 due to non-steatotic hepatopathy (non-specific inflammation in one case, and non-specific granuloma in the other). Though we routinely take biopsy of all accepted donors, one donor was rejected intraoperatively because of an irregular liver border and nodular surface. Fifty cases of LDLT were performed at the West China Hospital, Sichuan University. The evaluation process yielded 10 cases with a volume of remnant liver of more than 30%, which would make a potential donor ineligible (
15). In our study, 4.8 % of cases were excluded due to small-size liver.
Schroeder et al. reported that 40.8% of potential donors were rejected due to unfavorable anatomy, mostly inappropriate hepatic volumes. Two candidates were rejected due to the presence of 3 or more vascular and biliary variants (
18). However, the proportion of potential donors rejected due to unfavorable anatomy in our study was only 9.5%. This was due to portal vein variants (trifurcation) in 9 (7.1%) cases, biliary anomaly in 2 (1.6 %) cases, previous major operation (nephrectomy) in one (0.8 %) case, and small-size liver in 6 (4.8 %) cases.
We believe that the stepwise approach to donor preparation used in our study is cost effective. In a previous study, the reported costs of donor evaluation were 567 € (Euro) for step 1, 794 € for step 2, 1462 € for step 3, 185 € for step 4, and 1581 € for step 5, for a total cost of 4589 € (
14). In our study, the evaluation procedure was less expensive. The cost of the complete evaluation procedure was $1455 (The US dollars, approximately 1110 €), including $55 for the preliminary evaluation phase, $300 for step 1, $400 for step 2, and $700 for step 3. Professional fees were not included, similar to the previous study. Though, this cost may appear low, in a country with limited resources and a university-based transplant program serving low-income patients lacking health insurance coverage, this cost is considered high, especially if more than one donor is tested for a single recipient. In conclusion, Factor V Leiden mutation is a new significant cause of rejection among Egyptian potential living liver donors. A stepwise approach to donor evaluation is cost-effective. Implementation of cadaveric liver transplantation would spare the expense of donor preparation as well as the surgery risk imposed on donor. Because of the very low rate of donor rejection as well as abnormal findings in phase 2, and a much higher number of rejections after CT scanning, we would change our protocol, so that CT scanning can be performed much earlier to check for potential anatomical and size contraindications for liver donation in potential donors.