COMPARISON OF C-PEPTIDE LEVELS IN MONOGENIC FORMS OF DIABETES WITH OTHER TYPES OF DIABETES: A SINGLE-CENTER STUDY.

Area of Science:

• Endocrinology
• Metabolic Disorders
• Clinical Diagnostics

Background:

• Accurate diabetes mellitus classification is crucial for effective management.
• Monogenic diabetes, type 1 diabetes mellitus (T1DM), and type 2 diabetes mellitus (T2DM) present diagnostic challenges.
• C-peptide levels reflect endogenous insulin production and can aid in differentiating diabetes types.

Purpose of the Study:

• To assess the clinical utility of C-peptide levels in distinguishing monogenic diabetes from T1DM and T2DM.
• To compare C-peptide levels across different diabetes mellitus subtypes at diagnosis.

Main Methods:

• Retrospective analysis of 104 patients diagnosed with monogenic diabetes, T1DM, or T2DM.
• Measurement and comparison of C-peptide levels at the time of diabetes diagnosis.
• Inclusion criteria: patients over 16 years old diagnosed between April 2011 and December 2020.

Main Results:

• Median C-peptide levels varied significantly: MODY (maturity-onset diabetes of the young) 1.78 ng/mL, T1DM 0.86 ng/mL, and T2DM 2.38 ng/mL.
• A statistically significant difference was observed between MODY and T1DM C-peptide levels.
• No significant difference was found in C-peptide levels between MODY and T2DM groups.

Conclusions:

• C-peptide levels are useful in differentiating monogenic diabetes from T1DM.
• Distinguishing MODY from T2DM based solely on C-peptide levels is challenging.
• Clinical assessment is essential, as MODY C-peptide levels can overlap with both T1DM and T2DM ranges.