How is the transplantation of the kidney and pancreas done

Usually the kidney is transplanted extraperitoneally in the left lower quadrant and the pancreas intraperitoneally with part of the duodenum in the right lower quadrant.

The pancreas is removed from the donor together with the liver, so that damage of the blood vessels that perfuse them is avoided, and then their separation follows. The pancreas can be maintained in a University of

Wisconsin solution (special buffer solution) for up to 30 hours. The arterial perfusion of the pancreas is ensured with a graft from the bifurcation of the donor's iliac artery, of a Y shape, while the internal iliac artery is anastomosed to the splenic artery and the common or external iliac artery is anastomosed to the superior mesenteric artery.

Afterwards, the Y-shaped arterial graft of the donor is anastomosed with the external iliac artery of the recipient. The portal vein of the graft is anastomosed with the iliac vein or with the portal vein of the recipient.

The exocrine part of the graft is drained either to the urinary bladder of the recipient or, more often, to an intestinal loop.

Why is intestinal drainage of the exocrine part of the transplanted pancreas preferred today compared to drainage in the urinary bladder of the recipient, which was preferred in the past?

Although the survival of both the graft and the recipient are similar in both techniques, intestinal drainage is nevertheless superior concerning the occurrence of metabolic complications (dehydration, acidosis due to bicarbonate loss, pancreatitis and urinary tract infections).

Which medicines are administered postoperatively, after a simultaneous kidney and pancreas transplantation?

The immunosuppressive therapy differs from hospital to hospital. A relatively common regimen is described below.

As an initial treatment, many transplant centres prefer a regimen of four medicines including:

• a polyclonal or monoclonal antibody against the T lymphocytes, such as the antilymphocyte globulin (ALG), or the antithymocyte globulin (ATG) or the OKT3;

• mycophenolate mofetil (MMF, Cellcept), which selectively inhibits the inosine monophosphate dehydrogenase (IMPDH) and hence inhibits purine synthesis on which the T and the B-lymphocyte proliferation depends (some clinicians use azathioprine, instead of the MMF);

• cyclosporine A, at a dose adjusted so that its levels in the blood are higher than 200ng/ml or Tacrolimus Prograf (FK-506) 2 mg in the morning and in the evening, half an hour before meals (appearance of tremor and headache may constitute signs of overdosage);

• methylprednisolone (Medrol) or prednisone, received with the food and together with antacids.

The maintenance treatment usually includes cyclosporine, MMF or azathioprine and corticosteroids that are gradually decreased. Recently, Rapamycin (sirolimus) has been used as a maintenance treatment, or a medicine that inhibits the complete activation of T lymphocytes, or Daclizumab, an immunosuppressant humanized monoclonal antibody IgG1. This is selectively bound to the alpha-subunit (Tac subunit) of the interleukin-2 receptor, which is expressed on the surface of the activated lymphocytes.

Apart from the immunosuppressive medicines, the following are frequently prescribed on a chronic basis (indicative list):

• lansoprazole or omeparazole (proton pump inhibitors) and antacids for gastric protection;

• aspirin, for avoidance of thromboses;

• ganciclovir, for protection against megalocytovirus infections;

• co-trimoxazole, for the avoidance of infection from Pneumocystis carinii;

• florinef (fludrocortisone), for the avoidance of orthostatic hypotension;

• magnesium gluconate, for avoidance of serum magnesium decrease caused by the FK-506;

• potassium and perhaps sodium bicarbonate if their levels are low;

• clotrimazole (pills), for avoidance of mycoses from Candida;

• multivitamin preparations.

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