Evaluation of β-cell function in diabetic Taiwanese children using a 6-min glucagon test

Abstract

This study evaluates the effects of glucagon 30 mug/kg (maximal 1 mg) on beta-cell function in children by C-peptide determined before and 6 min after intravenous administration. From 1990 to 2005, 118 Taiwanese children with newly diagnosed diabetes mellitus (98 children with type 1 and 20 children with type 2) and 29 normal Taiwanese children were enrolled in this study. Fasting and 6-min post-glucagon C-peptide levels were analyzed. In the pre-pubertal group, the median fasting serum C-peptide levels were 0.2 and 0.8 nmol/l in type 1 diabetes and normal children, respectively. These levels rose to 0.3 and 1.9 nmol/l after glucagon stimulation. In the pubertal group, the median fasting serum C-peptide levels were 0.3, 1.0 and 0.9 nmol/l in type 1 diabetes, type 2 diabetes and normal children, respectively. They rose to 0.4, 2.5 and 2.7 nmol/l after glucagon stimulation. Both fasting and post-glucagon C-peptide levels in type 1 diabetes patients were significantly lower than those of normal children and children with type 2 diabetes. The optimal cut-off values to distinguish type 1 diabetes patients from those with type 2 as determined by the receiving operating characteristic curve were 0.7 and 1.1 nmol/l, respectively. The sensitivities of both C-peptide values were 93%. The post-glucagon C-peptide level was more powerful in distinguishing type 1 diabetes from type 2 diabetes with higher specificity (95% vs. 85%). The 6-min glucagon test is valuable in assessing beta-cell function in children and can help pediatricians in the differential diagnoses of diabetes mellitus in children.

Home urine C-peptide creatinine ratio testing can identify type 2 and MODY in pediatric diabetes

“…This is in contrast to Ludvigsson et al who identified that a C‐peptide > 1.0 nmol (equivalent to postprandial UCPCR of 1.8 nmol/mmol) at diagnosis has a predictive value of 46% (1 in 2.1 chance) to discriminate type 1 from non‐type 1 diabetes . This supports other studies in children where C‐peptide at diagnosis was shown to discriminate type 1 from type 2 diabetes with sensitivity varying from 83 to 95% . The metabolic presentation of patients may determine the variable sensitivities of C‐peptide reported in these studies because glucotoxicity at diagnosis may give an artificially low C‐peptide result .…”

Diagnostic criteria for acute‐onset type 1 diabetes mellitus (2012): Report of the Committee of Japan Diabetes Society on the Research of Fulminant and Acute‐onset Type 1 Diabetes Mellitus

“…and 97% (95% CI 86-100%) and 86% (95% CI 76-93%) in patients with a duration of diabetes >2 years. Furthermore, in Taiwanese patients with childhood-onset type 1 diabetes, Tung et al 10 reported that median fasting serum CPR level was 0.2 nmol/L (0.6 ng/mL) at disease onset. Based on these data, we decided to use 'fasting serum CPR <0.6 ng/mL' as a definition of endogenous insulin deficiency.…”

Urinary C-Peptide/Creatinine Ratio Can Distinguish Maturity-Onset Diabetes of the Young from Type 1 Diabetes in Children and Adolescents: A Single-Center Experience

“…Other studies in children have shown that C-peptide at diagnosis could differentiate T1DM from T2DM with sensitivities varying from 83 to 95% [20,21,22]. Katz et al [21] demonstrated that a C- peptide level of 0.85 ng/ml had a sensitivity of 83% and a specificity of 89%.…”