Islets Allotransplantation Into Gastric Submucosa in a Patient with Portal Hypertension: 4-year Follow-up

Islets transplantation is an established treatment method for patients suffering from brittle diabetes with hypoglycemia unawareness. The standard implantation technique is through the portal vein into the liver. In case of liver diseases or portal hypertension, finding an extra-hepatic site is recommended. There have been attempts to perform islets transplantations into muscles and into the gastric submucosa.

The aim of this study is to show a 4-year follow-up of allotransplantation into gastric submucosa in a case of portal hypertension observed during the procedure of islets infusion.

A 36-year-old woman with complicated diabetes for over 30 years was selected to receive simultaneous islets and kidney transplantation. The patient underwent an unsuccessful simultaneous pancreas and kidney transplantation 2 years earlier in another transplantation center. The patient's daily insulin requirement was 60 IU, which corresponded to 1.15 IU/kg of body weight. The HbA1c level was 7.4%. C-peptide levels, both fasting and stimulated, were 0.01 ng/mL. On December 7, 2013, the patient received transplanted kidney and islets procured from the same donor. Only 124,000 islets equivalents (IEQ) were isolated (2400 IEQ/kg body weight). Islets were suspended in 300 mL of Ringer's solution along with albumin, antibiotics, and heparin. After infusing 100 mL of the islets suspension into the portal vein, pressure in portal vein increased from 5 mm Hg to 23 mm Hg. Despite stopping the infusion, pressure did not drop after 30 minutes. The decision was made to transplant the reminder of the islets (200 mL) into the gastric wall.

No complications were observed after the procedure. Serum creatinine level was 1.6 mg/dL on day 10 and 1.5 mg/dL 4 years after the transplantation. Fasting C-peptide levels were 1.7, 0.65, 0.55, 0.69, 0.68, and 0.2 ng/mL at 1, 3, 6, 12, 18, and 36 months after the transplantation, respectively. HbA1c levels were 5.2, 6.4, 4.7, 5.2, and 5.9% at 3, 6, 12, 18, and 36 months, respectively. The patient's insulin requirement dropped to 15 U/day immediately after transplantation and equaled 20 and 27 U/day at 18 and 48 months after the simultaneous islet and kidney transplantation, respectively.

Allotransplantation of islets into the gastric wall may be a safe alternative in cases of contraindications for transplantation into the portal vein.