Kidney paired exchange is an established method of overcoming incompatibility in donor-recipient pairs and expanding the living-donor pool. It is infrequently performed in developing countries. We report the first kidney paired exchange in Pakistan, successfully performed at our center. One donor-recipient pair consisted of a 38-year-old female recipient (blood type, B positive) and her 40-year-old husband (A positive) as the potential donor. The second pair consisted of a 30-year-old male recipient (A positive) and his 30-year-old wife (B positive) as the potential donor. The donors were exchanged with the recipients, and both pairs were antigen matched for human leukocyte antigen A and human leukocyte antigen DR. Luminex antibody screening was negative, as were the crossmatches for T and B cells and for IgG and IgM. The transplant procedures and recoveries proceeded uneventfully. The recipients are maintaining serum creatinine levels around 0.78 mg/dL and 0.90 mg/dL, 1 year after transplant. Kidney paired exchange is a relatively low-cost option for overcoming the barrier of incompatibility in a resource-constrained setting.
Key words : Incompatibility, Paired kidney exchange, Transplant
The incidence of end-stage renal disease is increasing worldwide and in Pakistan is estimated at about 200 per million population, and less than 10% of patients have access to renal replacement therapy.1 Kidney transplant remains the best option for treatment. However, there is a gross imbalance between the rate of organ donation, both deceased and living-related, and the demand for organs.2,3 Several methods have been used to increase the number of organs available, including enlarging the deceased-donor pool, ABO-incompatible transplant, laparoscopic donor nephrectomy for living donors, use of marginal donors, accepting altruistic donors, and paired kidney donation. Kidney paired exchange (KPE) increases access to living-donor grafts.4,5
The process of KPE is an established method of overcoming incompatibility in donor-recipient pairs (DRPs). It is practiced widely throughout the world, but its use is infrequent in developing countries because of the complexity of donor issues, a lack of awareness about the exchange method, and logistic barriers. This method seeks to address the acute shortage of organs by accessing the pool of living donors who want to donate a kidney to a family member but cannot do so because of issues such as incompatible blood types or antigen sensitization. In a donor-exchange program that strictly limits it scriteria for incompatibility to blood group type, only type A and type B pairs would mutually benefit from paired donation. However, if the criteria for incompatibility are expanded to crossmatch-positive DRPs, then type AB and type O recipients also benefit from paired donation. Therefore, exchange programs allow for both blood group types, mismatched DRPs and crossmatch-positive DRPs.6
Here, we share our experience with the first KPE performed in this country. We describe 2 DRPs that were ABO incompatible and had no other suitable donors in the family.
A 38-year-old female patient, blood type B positive, had only 1 potential donor, her husband, whose blood type was A positive. Her father was not alive, her mother was 80 years of age, and her 2 brothers were disqualified on the basis of age (62 years) and hypertension. The patient had 3 sisters: 1 was 60 years of age, 1 was 55 years of age and hypertensive, and 1 was not willing to donate due to pressure from her in-laws. Neither the patient nor the potential donor had a family history of renal disease.
A 30-year-old male patient, blood type A positive, had a single potential donor, his 30-year-old wife, whose blood type was B positive. The patient’s father was not alive, and his mother was 70 years of age. He had 4 brothers: 1 was 42-years-old with an incompatible ABO blood type (B positive), the second was 38 years of age and diabetic, the third was 32 years of age and hypertensive, and the fourth was 28 years old and not willing to donate due to pressure from his spouse. The patient had 1 sister, who was hypertensive. Neither the patient nor the potential donor had a family history of renal disease.
Both patients were on hemodialysis for the previous 2 years and were waiting for a kidney transplant. In the absence of a deceased-donor program, no kidneys were available. We offered them the option of swapping, explaining at length all possible benefits and risks. Both pairs discussed this opportunity with their families and eventually gave consent. The donors were swapped with the recipients, as shown in Figure 1.
Both pairs were matched for 2 antigens: human leucocyte antigen (HLA)-A and HLA-DR. Luminex antibody screening was 0%. Lymphocyte cytotoxicity and flow cytometry crossmatch for T and B cells, and screening for IgG and IgM, were negative. The transplant procedures and patient recoveries were uneventful; both recipients were induced with antithymocyte globulin, and maintenance immunosuppression consisted of tacrolimus, mycophenolate mofetil, and corticosteroids. The recipients are maintaining serum creatinine levels around 0.78 mg/dL and 0.90 mg/dL, 1 year after transplant.
Living kidney donation offers superior outcomes and is the most readily expandable source of kidneys for transplant. The 2 greatest barriers to improving living-donation rates are ABO incompatibility and HLA sensitization. The method of KPE offers a relatively low-cost option for overcoming the incompatibility barrier. It is feasible, successful, and, if applied to larger donor pools, capable of expanding access to renal transplant.2-4
Grafts from KPE are used when a healthy donor is unable to donate to his or her intended recipient. In KPE transplant, the healthy donor from 1 pair donates his or her kidney to the recipient from another mismatched pair; in exchange, the second pair’s donor gives a kidney to the first pair’s recipient. The concept of KPE was first described by Felix Rapaport in 1986.7 However, the technique was not accepted in Europe, as most transplant centers considered unrelated transplant in any form as illegal. The first use of KPE was in South Korea in 1991 where, because of cultural and religious reasons, organ exchange between living donors is easier to accept than the concept of brain death and the use of organs from deceased donors.8 Switzerland and the United States performed their first KPE transplants in 1999 and 2000.3,4 Subsequently, several other countries in Europe have legalized the procedure.3-6 Our “swap” procedure, initiated for the first time in Pakistan, is pioneering. Encouraged by the promising initial results, the Sindh Institute of Urology and Transplantation is planning to expand this program and, consequently, several of the potential kidney-exchange pairs have been identified. Their workups are in progress.
In conclusion, the shortage of kidney donors can be partly overcome by a KPE living-donor kidney transplant program, especially in countries where deceased-donor programs are in the preliminary stages.
Volume : 15
Issue : 1
Pages : 76 - 78
DOI : 10.6002/ect.mesot2016.O63
From the 1Department of Medical Social Welfare, the 2Department of Immunology,
the 3Department of Transplantation, the 4Department of Clinical Chemistry, and
the 5Department of Urology Sindh Institute of Urology and Transplantation,
Acknowledgements: The authors have no financial disclosures and have no conflicts of interest to disclose. We would like to thank Professor Jeremy Chapman and Professor Muhammad Mubarak for their valuable guidance in preparing this manuscript.
Corresponding author: Naveeda Nizam, Department of Medical Social Welfare, Sindh Institute of Urology and Transplantation,Karachi-74200, Pakistan
Phone: +922 19 921 5752
Figure 1. Kidney Swap Transplant Between Incompatible (Blood-Group Mismatch) Donor-Recipient Pairs