Urinary C-peptide creatinine ratio is a practical outpatient tool for identifying hepatocyte nuclear factor 1-{alpha}/hepatocyte nuclear factor 4-{alpha} maturity-onset diabetes of the young from long-duration type 1 diabetes.

Besser, Rachel E J; Shepherd, Maggie H; McDonald, Timothy J; Shields, Beverley M; Knight, Bridget A; Ellard, Sian; Hattersley, Andrew T
Diabetes care; 2011 Feb;34(2):286-91. PMID: 21270186
Peninsula National Institute for Health Research Clinical Research Facility, Peninsula Medical School, University of Exeter, Exeter, UK.


Hepatocyte nuclear factor 1-α (HNF1A)/hepatocyte nuclear factor 4-α (HNF4A) maturity-onset diabetes of the young (MODY) is frequently misdiagnosed as type 1 diabetes, and patients are inappropriately treated with insulin. Blood C-peptide can aid in the diagnosis of MODY, but practical reasons limit its widespread use. Urinary C-peptide creatinine ratio (UCPCR), a stable measure of endogenous insulin secretion, is a noninvasive alternative. We aimed to compare stimulated UCPCR in adults with HNF1A/4A MODY, type 1 diabetes, and type 2 diabetes.