Simultaneous pancreas/kidney transplantation at the Penn Transplant Institute
The Penn Transplant Institute offers simultaneous pancreas/kidney transplants to improve kidney graft and patient survival vs. kidney transplant alone.
The Penn Transplant Institute offers simultaneous pancreas/kidney (SPK) transplantation, a procedure with the potential to improve both kidney graft and patient survival in comparison to kidney transplantation alone.
At Penn, SPK is offered to insulin-dependent diabetic patients age 60 and under with end stage renal disease (ESRD), typically as a consequence of diabetes mellitus, the leading cause of kidney failure. About 85% of pancreas transplants in the United States occur as SPKs. While the majority of these procedures occur in type 1 diabetics, type 2 diabetics accounted for 23% of SPKs performed in the US in 2020 (American Journal of Transplantation, 2022).
SPK offers unique advantages to patients with diabetic ESRD, whose treatment options are limited to kidney transplantation alone or peritoneal dialysis or hemodialysis. Kidney transplantation is an ideal approach, but the median wait time for a good quality deceased donor kidney in the United States is now 3.6 years (5-8 years in the Mid-Atlantic region).
Most patients anticipating a kidney transplant will undergo dialysis as a bridge to transplant.
Dialysis is associated with significant mortality rates, however, and carries many additional risks and complications for the diabetic population. Generally, diabetic patients on dialysis have a life expectancy of 3 to 5 years.
Survival rates: SPK vs. kidney transplantation alone
Kidney transplantation, alone or in combination with a pancreas, is the only approach that can preempt or minimize dialysis exposure for patients with end-stage kidney failure. However, kidney transplantation with continued insulin therapy does not resolve the condition that caused kidney failure in the first place.
To achieve this end, experienced transplantation centers, including the Penn Transplant Institute, have been transplanting a pancreas either at the time of kidney transplant (e.g., SPK), or following kidney transplantation alone (pancreas after kidney transplantation, or PAK).
Five-year survival rates for kidney transplantation from deceased donors is approximately 86% (93% for living donor transplants). By comparison, the national patient survival rate for SPK at five years post transplant is 92.7%.
SPK is more widely used than PAK because most patients do not have a living donor. The attendant advantages of SPK vs PAK include the relative benefits of a single procedure versus multiple surgeries, and an immunologic benefit for the pancreas in that the kidney from the same donor can signal early rejection of the pancreas, conferring increased long term pancreas graft survival compared to PAK.
Recent changes in organ allocation may also have benefits for SPK
With reference to SPK, the process of organ allocation shifted in December 2014, when the United Network for Organ Sharing (UNOS) launched a new system to disentangle the pancreas and kidney wait lists and enhance the possibility that both organs can be allocated to candidates for SPK transplant.
This has utility not only for timing (the waiting list for a pancreas is much shorter than that for a kidney) but for improved kidney quality, since the risk factors that impact kidney quality are typically absent among pancreas donors.
Outcomes data
- In 2020 there were 19,458 living recipients of pancreas transplants in the US.
- The National patient survival rate for SPKs is 97.14% at one year, 92.7% at five years, and 79.1% at 10 years post transplant.
- The rate of kidney graft function (as part of the SPK transplant) is 95.8% at one year and 66.6% at 10 years.
- Nationally, the rate of pancreas graft function at one year for SPK is 93%.
- Long term graft survival is excellent for SPK transplantation; the point in time when 50% of grafts are lost/still functioning is >15 years (for both the pancreas and the kidney).
- In a large nationwide cohort study performed in the Netherlands in 2020 that compared SPK to kidney transplantation alone, SPK recipients with a functioning pancreas graft at 1 year (91%) had the highest rate of survival (median 17.4 years) (Diabetes Care, 2020).
- The rejection rate for SPK is lower (10.6%) compared to PAK (12.5%) and PTA (21.8%).
- While the average wait for a simultaneous kidney and pancreas transplant varies by blood type and area of the country, the median wait time for SPK in the Mid-Atlantic region is between 1 and 3.5 years.
SPK at the Penn Transplant Institute
The Penn Transplant Institute is exceptional for its concern for the long-term well-being of patients, and the experience and skill of its surgeons, who have the expertise to be both aggressive in pursuit of the best quality organs, and to manage potential complications should they arise.
As shown in Figure 1, kidney and/or pancreas transplantation typically does not involve removing the native organs (unlike heart, lung and liver transplant).
In the instance of SPK, the donated kidney is placed in the lower abdomen, to the right or left of the bladder to which it is attached by its ureter; it receives blood flow from the nearest iliac artery and vein.
The pancreas is typically transplanted on the right side with a segment of duodenum anastomosed to the recipient’s jejunum and receives its blood flow from the common iliac artery; the venous outflow can be systemic (from the inferior vena cava or common iliac vein), or portal (superior mesenteric vein).
Case study
Bill, a 48-year-old male, was referred to the Penn Transplant Institute for a kidney transplant for biopsy-proven diabetic nephropathy.
Bell’s medical history included stage 4 chronic kidney disease and type 2 diabetes for 23 years, requiring insulin for 10 of those years.
Despite efforts to care for himself, his many complications (in addition to end-stage renal failure) included diabetic retinopathy, cataracts, and peripheral neuropathy. His GFR at presentation was 23 (normal range 100 – 130); his A1C was 7.9; his blood was type A. Among other concerns, Bill’s looming kidney failure meant he would soon have to begin dialysis.
At the Penn Transplant Institute, the SPK team evaluated Bill to better understand his circumstances and burden of disease, his health literacy, and his ability to understand the risks and benefits of his transplant options. The purpose of these efforts was to help him make an informed decision about his future and to ensure that the decision for transplant was in concordance with his wishes.
Bill was counseled that his options included simultaneous pancreas/kidney transplantation involving a living or deceased donor kidney transplant, with the option of a pancreas after kidney transplantation (PAK).
However, like so much else for individuals with diabetic kidney disease, Bill’s future depended upon other findings from his transplant evaluation, including cardiac status, vascular disease, hypercoagulability, and any other as yet undisclosed issues he might have.
Options, stratagems, and advantages
Bill now entered an interim defined by time dependencies, opportunity, risk, strategy, design, and occasionally, luck.
Whether or not he achieved his ultimate objective — freedom from dialysis and insulin — would depend upon decisions made in the initial stages of his journey. One critical early consideration was the need to avoid dialysis and its many adverse effects. The median lifespan of individuals on hemodyalysis is only 5 - 10 years. Thus, for patients at risk for kidney failure, it’s important to avoid or minimize dialysis time by finding the most direct path to a kidney transplant, from a living donor, if one is available.
In the next few weeks, however, all of Bill’s potential living donors proved to have disqualifying physiological issues, making SPK an increasingly attractive option to achieve his goals.
SPK: An option for patients seeking kidney transplantation
Because pancreas donors are typically younger and fitter, the quality of a kidney from a deceased pancreas donor is often as good as — or sometimes better than — that from a living donor. For diabetic patients, successful pancreas transplant as part of an SPK protects against the recurrence of diabetic nephropathy, and can slow or prevent the other complications of diabetes (Diabetes Care, 2002).
Bill was advised to get on the waiting list for a kidney and pancreas, although he was technically ineligible to accrue waiting time for the former as his GFR was still above 20ml/min.
The UNOS qualifying time (date from which waiting time can accrue) for a kidney can’t begin until the GFR is 20 or below, but for pancreas wait time, accrual begins on the date of listing. By getting on the waiting list for an SPK, therefore, patients will accrue pancreas waiting time, which is important in case they are able to obtain a living donor kidney, at which time the SPK waiting time converts seamlessly to their pancreas waiting time for PAK.
Bill was fortunate in that his clinical situation favored SPK. Despite the hardships of diabetes and struggling with hypoglycemic unawareness, he was genuinely motivated to be insulin free, had demonstrated compliance with his medical regimens, and expressed a willingness to take on additional surgical risk (over kidney alone transplantation) to gain freedom from diabetes. Furthermore, he was young and relatively lean (BMI 28), both ideal characteristics for an SPK candidate.
Bill was placed on the waiting list for a pancreas, and when his GFR dipped below 20 (as monitored by the transplant center), he began accruing kidney waiting time as well. A year later, when his GFR approached 14 and he was becoming symptomatic from his kidney failure, he started to receive organ offers.
The urgency for a transplant recipient approaching dialysis is to get an organ, and soon. What’s needed, however, isn’t just any organ, but the best organ available.
Soon thereafter, the PTI was notified about a potential organ donor with favorable characteristics for donation of a pancreas and a kidney. The donor was 27 years old with a BMI of 23; he had an A1C of 5.2 and a creatinine of 0.8. In the operating room, the pancreas and kidneys appeared completely normal. A virtual crossmatch confirmed that the donor and Bill were compatible.
SPK surgery
Bill was admitted to the Hospital of the University of Pennsylvania, to which the organs were transported soon afterward. At the hospital, he had a COVID test, labs, EKG, and a chest x-ray, while he awaited organ arrival.
While Bill was undergoing anesthesia, the transplant team was preparing the organs for transplantation, which takes between one and two hours to complete. As this process neared its completion, part of the team began the operation on Bill with a midline incision to inspect the internal organs and the vasculature, to determine where the kidney and pancreas would be implanted.
The practice at Penn is to put the kidney in first, which can usually be accomplished while the pancreas is being prepared. This minimizes cold time and also helps manage potassium for patients who are on dialysis. If extended cold time is a concern, the team may choose to anastomose the pancreas first.
Bill’s surgery went well, and at its conclusion, he was moved to the intensive care unit and monitored for one day for bleeding, clotting, and function of his newly transplanted organs.
By his second day, Bill was ambulatory and after a few days when it was evident that his GI system was returning to normal function, his diet was advanced, with careful attention to maintenance of hydration.
To keep Bill safe during recovery, he was followed intensively for the first month, during which time he returned to the clinic every week. He received labs twice a week for three months thereafter, and in the months beyond was monitored for the development of complications related to his history of longstanding diabetes, as well as immunosuppression-related side effects.
Patients having SPK have the lowest risk of pancreas rejection, which is good because this correlates with lower levels of immunosuppression and increased pancreas longevity, in contrast to PAK or PTA transplant recipients.
Bill’s recovery was uneventful, and at one year, his pancreas and kidney grafts show no signs of rejection, and his glycemic control was excellent. Although historically 50% of SPK patients are readmitted in the first year as a result of complications related to longstanding diabetes (including dehydration, nausea, gastroparesis, and constipation), Bill was not among them.
For more information about pancreas and kidney transplantation at the Penn Transplant Institute, please call 215-662-6200.
About the Penn Transplant Institute Pancreas Transplant Program
The Penn Transplant Institute pancreas transplant program was the first program in the region to offer pancreas transplant as treatment for type 1 diabetes, and is one of the leading transplant centers in the world researching islet cell transplantation.
As a member of the Clinical Islet Transplantation Consortium funded by the National Institutes of Health, we participate in clinical trials for islet transplantation in addition to clinical trials studying aspects of pancreas transplantation.
Faculty team
- Peter L. Abt, MD - Pancreas Transplant Surgeon
- Samir Abu-Gazala, MD - Pancreas Transplant Surgeon
- Matthew H. Levine, MD, PhD - Pancreas Transplant Surgeon