Lack of feedback inhibition of insulin secretion in denervated human pancreas

In this study, pancreas transplantation is used as a clinical model of pancreas denervation in humans. To assess the role of innervation on the feedback autoinhibition of insulin secretion, we studied four groups of subjects--group 1: 16 patients with combined pancreas and kidney transplantation (plasma glucose = 5.1 mM, HbA1c = 6.4%, creatinine = 86 mM); group 2: 8 patients with chronic uveitis on the same immunosuppressive therapy as transplanted patients (12 mg/day prednisone, 5 mg.kg-1.day-1 CsA); group 3: 4 uremic, nondiabetic patients in chronic hemodialysis; group 4: 7 normal, nondiabetic control subjects. The following means were used to study the groups: 1) a two-step hyperinsulinemic euglycemic clamp (insulin infusion rate = 1 mU and 5 mU.kg-1.min-1); and 2) a 0.3 mU.kg-1.min-1 hypoglycemic clamp (steady-state plasma glucose = 3.1 mM). Basal plasma-free IRI (84 +/- 6, 42 +/- 12, 72 +/- 12, and 30 +/- 6 pM in groups 1, 2, 3, and 4, respectively), basal C-peptide (0.79 +/- 0.05, 0.66 +/- 0.05, 3.04 +/- 0.20, and 0.59 +/- 0.06 nM in groups 1, 2, 3, and 4, respectively), and glucagon (105 +/- 13, 69 +/- 4, 171 +/- 10, and 71 +/- 5 pg/ml in groups 1, 2, 3, and 4, respectively) were increased in groups 1 and 3 with respect to groups 2 and 4 (P < 0.01). During euglycemic hyperinsulinemia, plasma C-peptide decreased by 45, 20, and 44% in groups 2, 3, and 4, respectively, but showed no significant change from the basal in patients with transplanted pancreases.(ABSTRACT TRUNCATED AT 250 WORDS)

Octreotide administration in the treatment of pancreatic fistulae after pancreas transplantation

Among the surgical complications of pancreas transplantation are pancreatic fistulae, which arise rather frequently. Suppression of exocrine secretion with polymers has succeeded in reducing the rate of this complication. Nevertheless, in some instances, pancreatic fistulas may occur. Thirty pancreas transplantations were performed in 27 diabetic patients. In 5 cases a pancreatic fistula occurred and was drained after the insertion of a catheter for the collection of secretions. A serous liquid was collected with a high concentration of amylases (61604 +/- 19562 IU/24 h). Fistula output was 280 +/- 87 ml/24 h. Patients were treated with octreotide, administered subcutaneously in a dose of 300-750 micrograms/day. In all patients a progressive reduction in fistula output was observed after a mean of 16 + 2 days. Fistula flow rate dropped to 24 +/- 10 ml/24 h--a reduction of 95% +/- 5% and drainage was subsequently stopped. Sonographic follow-up did not show recurrence of peripancreatic collections in these patients. All patients were insulin-independent up to 12-44 months after surgery.

Secondary failure of oral hypoglycaemic agents in lean patients with type 2 diabetes mellitus: insulin sensitivity, insulin response to different stimuli, and the role of cyclic-AMP

The aim of this study was to evaluate the insulin (IRI) response to different stimuli and insulin sensitivity in Type 2 diabetic patients responsive to oral hypoglycaemic agents (OHA) and in Type 2 diabetic patients with secondary failure of OHA (SF), all patients being of normal body weight (relative body weight less than 120%), and the possible role of cyclic AMP in the reduced IRI release. SF patients, without islet cell antibodies (ICA), with hyperglycaemia lasting more than 3 months, underwent tests with i.v. tolbutamide (n = 21), i.v. glucose (n = 14), i.v. glucagon (n = 19), i.v. arginine infusion (n = 18); the arginine infusion was repeated in 12 patients during administration of aminophylline, an inhibitor of phosphodiesterase. The same tests were performed in groups of 8 to 15 OHA patients and in groups of 6 to 17 healthy subjects. During all the tests, blood glucose levels were higher in SF patients, than in OHA patients and in healthy subjects. Both SF patients and OHA patients had no IRI response to glucose; SF patients, in contrast to OHA patients, had a reduced IRI response to tolbutamide and to glucagon. The IRI response to arginine was not different in OHA, in SF patients and in healthy controls, but was significantly enhanced by aminophylline only in healthy controls. Insulin infusions (1.66 mU/Kg/min for 90 min) were performed in OHA patients and in SF patients at blood glucose levels of 150 and of 250 mg/dl: during the last 60 min, the amount of glucose metabolized (M), and the insulin sensitivity (M/I) index were greater in OHA than in SF patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Pancreas and kidney transplantation: the San Raffaele Hospital (Milan, Italy) experience

Results of 33 simultaneous pancreas and kidney transplantations performed at the San Raffaele Hospital, Milan, Italy are presented. In 26 cases segmental neoprene duct-injected grafts were transplanted and in seven cases, duodenopancreatic bladder-drained grafts. Five-year patient, kidney and pancreas survival were respectively, 89%, 72% and 58%. Five-year survival in patients with technically successful pancreas transplants was 73%. Thrombosis occurred in 20% of cases. Mortality was 6% and overall morbidity 76%. Surgical complications were present in 51% of cases.

Effect of pancreas transplantation on diabetic retinopathy: a 20-case report

In order to study the effects of normoglycaemia on diabetic retinopathy, 20 diabetic uraemic patients who underwent a kidney-pancreas transplantation were evaluated before and after surgery (6.9 months and once a year). The control group consisted of 12 uraemic patients who underwent kidney transplantation alone. At each follow-up examination a complete clinical examination and a retinal fluorescein angiography were performed. The eyes with end-stage retinopathy at baseline were excluded from the study. The analysis of the results showed no significant differences in the two groups. The diabetic retinopathy at the moment of the transplantation was already too advanced to benefit from the better glycaemic control.

Neurophysiological study of the effect of combined kidney and pancreas transplantation on diabetic neuropathy: a 2-year follow-up evaluation

Previous study have reported a significant improvement of peripheral neuropathy following combined pancreas and kidney transplantation attributed to improvement of blood glucose control by some authors and to elimination of uraemia by others. To asses the specific role of uraemia and hyperglycaemia in neuropathy, 16 diabetic uraemic patients with combined pancreas and kidney transplantation were compared to 9 diabetic patients with a renal graft only. Neurophysiological studies of peripheral neuropathy included ulnar and deep peroneal nerve motor conduction velocity, median and sural nerve sensory conduction velocity were performed at baseline and 1 and 2 years after transplantation. One year after transplantation mean nerve conduction velocity significantly improved in both groups. However, changes were statistically significant in the kidney-pancreas group only. At the 2 year follow-up nerve conduction velocity had increased further in the pancreas-kidney group only. These data suggest that improvement of nerve conduction velocity following pancreas and kidney transplantation is predominantly due to the long-term euglycaemic state.

Metabolic control after kidney and pancreas transplantation: whole series results and effects of segmental duct obstruction versus whole pancreas with bladder diversion technique

From October 1976 to December 1990 181 pancreatic transplants were performed in our centre on 171 Type 1 (insulin-dependent) diabetic patients. Oral glucose tolerance test evaluated 1 year after surgery in 31 subjects showed an impaired glucose tolerance at 120 min (blood glucose 9.5 +/- 0.6 mmol/l). Similar results were obtained in seven patients 3 years after transplantation (blood glucose at 120 min 8.3 +/- 1.08 mmol/l). 24h metabolic profiles performed at the same intervals showed near normal blood glucose levels and good insulin release. Preliminary data concerning a randomized, comparative study between whole pancreas with bladder diversion and segmental pancreas transplantation, showed better metabolic control in the patients who received the whole pancreas, probably due to the greater islet mass grafted.

First peak insulin release after intravenous glucose and arginine is maintained for up to 3 years after segmental pancreas transplantation

In this study we have investigated blood glucose and serum free insulin response to glucose and to arginine orally or intravenously, 3 months and 3 years after a successful segmental, neoprene-injected, pancreas transplantation. Serum insulin responses to different secretagogues were normal 3 months after transplantation; they remained normal up to 3 years after transplantation.

Effect of pancreas transplantation on life expectancy, kidney function and quality of life in uraemic type 1 (insulin-dependent) diabetic patients

The aim of our study was to evaluate the effects of haemodialysis, kidney transplantation and simultaneous kidney and pancreas transplantation on survival of diabetic subjects and on kidney function. 40 Type 1 (insulin-dependent) diabetic patients received a kidney transplantation: in 31 cases the kidney was transplanted simultaneously to a pancreas graft from the same donor (KP group), while in 9 cases the pancreas was not available (K group). 44 uraemic Type 1 (insulin-dependent) diabetic patients on dialysis and in waiting list for kidney transplantation, constituted the control group (HD group). Patient survival rate 1, 3 and 5 years following transplantation was better in KP group (93%, 89%, 89%, respectively) and in K group (88%, 88%, 73%, respectively) and in HD group (88%, 62%, 51%, respectively). Kidney graft survival at 1, 3 and 5 years post-transplant was better in KP group (93%, 72%, 72%, respectively) than in K group (76%, 61%, 31%, respectively). 1 year after transplantation, patients of the KP group who had lost the pancreas for technical reasons (thrombosis) were included in the K group so as to evaluate the effect of the transplanted pancreas on long-term patient and kidney survival. Patient survival rate in the KP group (17 patients) at 2 and 4 years was 100%, while at the same intervals it was 78% in the K group (13 patients). Kidney graft function rate at 2 and 4 years was 93% in the KP group (17 grafts) and 54% and 27% respectively in the K group (14 grafts).(ABSTRACT TRUNCATED AT 250 WORDS)

Diabetic retinopathy after successful kidney-pancreas allotransplantation: a survey of 18 patients

To investigate the effects of normoglycaemia on diabetic retinopathy, we evaluated 18 uremic diabetic patients before and after successful pancreas kidney transplantation. In all, 12 uremic diabetic patients who submitted to kidney transplantation alone served as the control group; 4 of these subjects received a kidney transplantation alone, whereas 8 underwent a double kidney-pancreas transplantation but lost the pancreas graft within the first few weeks post-surgery. The mean age and the mean duration of both diabetes and dialysis were comparable in the two groups. All patients were studied prior to and at 6 and 9 months after surgery, then at annual intervals. Subjects were divided into three groups according to follow-up: less than 1 year, between 1 and 3 years and greater than 3 years. At each control visit, a complete clinical examination was performed by two independent examinators; retinal fluorescein angiography was carried out as well. The following parameters were evaluated: visual acuity, capillary closure, macular oedema, neovascularization at the disk and elsewhere and vitreous haemorrhage. A score ranging from -2 to +2 was assigned to each parameter for quantification of the variation between baseline values and those obtained at the end of the follow-up. This score was assigned by two different ophthalmologists. Eyes that were affected at baseline by end-stage diabetic retinopathy (secondary retinal detachment, neovascular glaucoma) were not entered in the study. A total of 18 eyes were lost to follow-up in the 2 groups because of laser treatment, cataract extraction, anterior ischaemic optic neuropathy and cytomegalovirus retinitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Endocrinometabolic effects of whole versus segmental pancreas allotransplantation in diabetic patients--a two-year follow-up

We have investigated the metabolic effects of segmental (neoprene-injected) pancreas transplantation versus whole (enteric-diverted) pancreas transplantation. Seventeen uremic insulin-dependent diabetes mellitus (IDDM) patients received a simultaneous pancreaticorenal transplant: in a prospective, randomized study, 9 patients received a segmental neoprene-injected graft (group A) while 8 patients received a total pancreaticoduodenal graft, with enteric diversion (group B). The immunosuppressive therapy was based on ALG, CsA, azathioprine, and steroids. Three months after surgery, patients were submitted to the following metabolic investigation: i.v. and oral glucose tolerance tests, Hba1, i.v. arginine test, and a 24-hr metabolic profile. The OGTT, HbA1, and metabolic profile were repeated 12 and 24 months after transplantation. At 3 months after transplantation, the OGTT showed delayed insulin secretion and higher blood glucose levels in group A. Serum insulin levels after IVGTT or arginine were higher in group B than in group A. OGTT at 12 and 24 months were unchanged in group B, while in group A a higher incidence of impaired glucose tolerance (IGT) and diabetes mellitus response were observed. HbA1 and blood glucose levels during the 24-hr profile showed good metabolic control in both groups at 3, 12, and 24 months. We can conclude that both the segmental and total pancreas transplantation restore a good metabolic control in IDDM patients, though a higher incidence of IGT and DM responses were observed after OGTT in the patients receiving a segmental graft. These abnormalities do not seem to interfere with metabolic control in everyday life. These results seem to be the consequence of the different B cell masses transplanted with these two techniques.