NOTE: This article was first published in February 2021 in Issue 12 of our Kidney Matters magazine
Over 40% of kidney patients receiving dialysis also have diabetes. For some of those with insulin-dependent diabetes the option exists of having a simultaneous pancreas and kidney (SPK) transplant. For many patients who receive a SPK transplant, life is completely transformed for the better.
A simultaneous pancreas and kidney (SPK) transplant is a big operation. In general, it is a much more complex operation than a kidney transplant by itself. The transplant operation lasts longer (four to eight hours on average) and involves two separate transplanting teams: one team preparing the pancreas for implantation and a separate team preparing the patient for the pancreas transplant. After the pancreas is transplanted, the kidney is then implanted. Both organs will have been donated by one deceased donor and will be transplanted into a patient with insulin-dependent diabetes mellitus and chronic kidney disease (CKD).
Which patients will be offered a simultaneous pancreas and kidney transplant?
Not everyone with CKD and diabetes is suitable for a SPK transplant. Our national guidelines stipulate that in order for a patient to be considered suitable for a SPK, they will have insulin-dependent diabetes and have less than 20% kidney function. Most people who have a SPK transplant have type 1 diabetes, but occasionally people with type 2 diabetes who require insulin injections will also be eligible for an SPK transplant.
People with type 1 diabetes tend to have been diagnosed at quite an early age (in their early teens or twenties). Their pancreas has ceased to produce insulin due to an auto-immune condition. Those with type 2 diabetes tend to be diagnosed later in life; these patients still produce insulin from their pancreas but the body’s ability to act on the insulin signal is reduced. In other words, they have insulin resistance.
Over the course of several years, some patients with diabetes will go on to develop various forms of organ damage. One of these is called ‘diabetic nephropathy’ (or ‘diabetic kidney disease’). Diabetes can also damage the eyes, nerves, and blood vessels.
We know that a good quality pancreas, transplanted along with a kidney from the same deceased donor, is likely to work well in a selected group of patients with diabetes.
We expect that the insulin secreted from the implanted pancreas will bring that patient’s blood sugar level down within minutes.Chris Callaghan Consultant Kidney and Pancreas Transplant Surgeon, Guy’s and St Thomas’ NHS Foundation Trust
The transplant work-up
When we meet a patient with insulin-dependent diabetes whose kidney function has declined to less than 20%, we assess their individual suitability for this form of treatment, as this will not suit all patients. Every person is different, with different expectations and a different medical history. So, in a series of consultations, we consider what the best treatment for this individual might be and talk through all of those options.
One of the first questions we would ask ourselves when considering someone for a SPK transplant is ‘are they fit enough to withstand and recover from this complex surgery?’ If a patient is deemed to be clinically obese, they may be asked to lose weight in order to mitigate the additional risks and anatomical difficulties associated with complex surgery in obese patients. We also look at a patient’s overall health and consider many other issues, including:
- Whether they have any heart disease
- The health of their blood vessels
- How much abdominal surgery they’ve had in the past
Whilst there is no national upper age limit for SPK transplants, most patients tend to be under the age of 60 years, as younger patients are more likely to be able to withstand this type of major surgery. That said, if a patient is over the age of 60 years but meets the qualifying criteria we would still consider them for the SPK transplant programme. It’s a case-by-case decision. It’s very rare for a child to be suitable for a SPK transplant. This is because it usually takes many years for advanced diabetic nephropathy to develop in a patient with diabetes.
The work-up for a SPK transplant can seem intense and protracted. There are often a lot of tests and we need to discuss what will happen in theatre, the risks of complex surgery, what recovery will look like and any potential complications that may occur during and after surgery.
Donor selection and organ retrieval
A pancreas suitable for transplantation will usually have come from a young, slim donor with few chronic health issues. This is because the pancreas is more sensitive to obesity than other organs in the body. The pancreas is a delicate organ, and it is close to many other organs such as the stomach and liver, and many major blood vessels. Therefore, it is more susceptible to being damaged in the organ retrieval process.
So, sadly, patients are often called in for a pancreas or SPK transplant and, just a few hours later while they are in the hospital, we discover that the pancreas we had hoped to transplant is not suitable for implantation due to fat within the pancreas or damage. The transplant cannot go ahead. This is such a disappointing time for the patient and the transplanting team.
The SPK transplant operation
The operation is carried out under a general anaesthetic. A large, usually vertical, incision is made in the patient’s abdomen. The artery and vein of the donated pancreas are then sewn into the patient’s artery and vein in the right-hand side of their lower tummy. The intestine that comes attached to the donated pancreas is sewn into patient’s intestine.
Through the same incision, the artery and vein of the donated kidney are sewn into the patient’s artery and vein in the left-hand side of their lower tummy. The ureter (the tube carrying urine from the kidney) is sewn into the patient’s bladder. A small, soft piece of plastic tubing called a stent is placed inside the ureter to help it heal. The patient’s own kidneys and pancreas are left in place, if they are still there. Once blood flow to the transplanted pancreas has been established in the operating theatre, we expect that the insulin secreted from the implanted pancreas will bring that patient’s blood sugar level down within minutes. And then, within an hour or so on the intensive care unit (ICU) the patient’s blood sugar level will be completely normal.
As a surgeon, this is very satisfying to see. On the other hand, it can take a few days for a transplanted kidney to start working and for the patient to come off dialysis if they were on it before the transplant.
A pancreas transplanted along with a kidney from the same donor tends to last longer than a pancreas transplanted alone. This is because any signs of rejection tend to also affect the kidney. Rejection in the kidney is quickly identifiable and can therefore be treated swiftly and effectively.
Most patients who have a SPK transplant leave hospital within two weeks of surgery. About one out of every three patients who have an SPK transplant needs to go back for more surgery in the first week or so after their transplant. Sometimes patients have major problems after SPK surgery and occasionally (about one out of every ten patients) the transplanted pancreas needs to be removed due to bleeding, infection or blood clots within it.
Most patients do very well after an SPK transplant – free of the ties of dialysis, insulin injections, and daily blood glucose monitoring. Some patients with good pancreas function after an SPK transplant notice that nerve or eye damage due to their diabetes gets better.
Average SPK transplant survival rates per 100 transplants (UK)
Pancreas – where the patient has good blood sugar control and does not require insulin
- At one year: 85 - 90
- At five years: 80 - 85
- At ten years: 50 - 60
- Many have good pancreas function for longer
Kidney – where the patient is free from dialysis
- At one year: 90 - 95
- At ten years: 75 - 80
- Most will have good kidney function for between 15 and 20 years