The Effect of BCG Vaccine on Recent Onset Type 1 Diabetes Mellitus Patients

Oh, Jeong Heon; Baik, Sei Hyun; Choi, Kyung Mook; Kim, Nan Hee; Park, Ie Byung; Choi, Dong Seop

Abstract

BACKGROUND: Type 1 diabetes mellitus (Type 1 DM) results from autoimmune destruction of -cells of the pancreas. Many treatments aimed at inducing remission of newly diagnosed type 1 DM or preventing of type 1 DM in high risk group are being conducted. BCG is known to modulate the development of spontaneous diabetes in animal model of type 1 DM. In some studies, single injection of BCG induced clinical remission in recent onset type 1 DM patients. However, the effect of BCG on human is still controversial. Thus, we performed a prospective study to evaluate the effect of BCG on type 1 DM.
METHODS
We enrolled a total of 23 type 1 DM patients within 6 months period. Randomly selected 14 patients were injected 0.1 ml BCG intradermally and 9 patients were injected normal saline. Fasting and postprandial 2 hour C-peptides, and insulin requirements were measured in all patients at enrollment and at 6, 12 and 24 months after BCG vaccination.
RESULTS
At enrollment, there was no significant difference in age, sex, duration of diabetes, HbA1-C, body mass index, fasting and postprandial 2 hour C-peptides, and insulin requirement between BCG group and control group. During follow-up, there was no significant difference in fasting and postprandial 2 hour C-peptides. However postprandial 2 hour C-peptides in BCG group were higher than those in control group at 12 and 24 months (p-value>0.05). Insulin requirements also were lower in BCG group than in control group at 12 and 24 months (p-value>0.05). Clinical remission has been sustained in 2 BCG vaccinated patients at 6 and 12 months. In one of the two patients, remission was sustained for 36 months.
CONCLUSION
BCG vaccine is safe and convenient to use, however, a large study is warranted for the use of BCG as a therapy of type 1 DM.