Diabetes Care, Vol 21, Issue 11 1944-1950, Copyright © 1998 by American Diabetes Association
Hypoglycemia after pancreas transplantation
JB Redmon, AU Teuscher and RP Robertson
Department of Medicine, the University of Minnesota, Minneapolis 55455, USA. redmo001@maroon.tc.umn.edu
OBJECTIVE: Hypoglycemia is a serious complication of therapy for diabetes.
Chronic hypoglycemia and the attendant decrease in quality of life have
been rationales for advocating pancreas transplantation as an alternative
treatment. However, reports have appeared that suggest that as high as
30-50% of pancreas transplant recipients have occasional symptoms of mild
hypoglycemia. Therefore, we studied glucose and hormone levels in
transplant recipients and healthy control subjects. RESEARCH DESIGN AND
METHODS: We studied glucose and hormone levels in transplant recipients
reporting frequent symptoms of hypoglycemia (n = 10), transplant recipients
without symptoms of hypoglycemia (n = 9), and healthy control subjects (n =
8) after a mixed meal and during a subsequent 24-h modified fast. All
transplant recipients were insulin-independent; were receiving prednisone,
cyclosporine, and azothioprine; and had functioning grafts with systemic
venous drainage. RESULTS: No significant differences were observed in the
fasting glucose, insulin, C-peptide, or glucagon levels when comparing the
symptomatic with the asymptomatic groups of patients who had undergone
successful pancreas transplantation. Similarly, no significant differences
were found in the immediate postprandial period after a mixed meal.
However, during the subsequent 24-h fast, glucose levels fell lower in the
symptomatic than in the asymptomatic group of patients receiving a
transplanted pancreas (71+/-2 vs. 81+/-2 mg/dl, P < 0.002). During the
fast, no significant differences were found in insulin, C-peptide, or
glucagon levels when comparing asymptomatic to symptomatic groups. Of 10
symptomatic recipients of pancreas transplantation, 5 reported symptoms of
hypoglycemia during the study. In four of these five subjects, the onset of
symptoms corresponded to nadirs in serum glucose, which occurred at values
2 SD or more below the mean glucose observed for the control and the
asymptomatic pancreas recipient groups. The serum glucose levels at the
time of symptoms in these four subjects were 55, 66, 51, and 57 mg/dl. In
each of these four subjects, symptoms abated and the glucose levels rose
spontaneously without intervention. One of these four subjects had elevated
insulin binding activity in his serum consistent with endogenous insulin
antibodies. This individual had a serum glucose value of 55 mg/dl at the
conclusion of the 24-h fast without symptoms. CONCLUSIONS: Among a group of
pancreas transplant recipients reporting frequent symptoms of hypoglycemia,
some individuals demonstrated transient, symptomatic postprandial
hypoglycernia. With the exception of one recipient with insulin antibodies,
no evidence was found for hypoglycemia during fasting. Although
postprandial hypoglycemia may occur in some pancreas transplant recipients,
it does not appear to be a highly significant clinical problem.