Background and hypotheses: Urinary C-peptide creatinine ratio (UCPCR) is a new, non-invasive, economical test recommended in differential diagnoses of maturity-onset diabetes of the young (MODY). There are a few studies on this topic. UCPCR values were determined as >0.2 and >0.7 nmol/mmol with a high specificity and sensitivity in differential diagnosis in the previous two studies, the values were evaluated in only three MODY types (HNF1A/HNF4A/GCK-MODY). We investigate UCPCR changes in six different MODY types along with the availability of previously defined UCPCR values in different MODY types.
Methods: A total of 28 patients genetically diagnosed with MODY were included in the study. Urine samples were collected 2 h after a standard lunch, which contained an appropriate calorie content consistent with patients ages and weights. UCPCR values were calculated for all cases, and correlations between them as wells as ratios reported from previous studies were analyzed alongside data about each patients MODY type and diabetes duration.
Results: Patient UCPCR was defined as 1.22±1.03 (0.13.97) nmol/mmol.The duration of diabetes in patients with UCPCR<0.7 nmol/mmol was 3.08±1.04 years, and it was 2.43±2.72 years in patients with UCPCR≥0.7 nmol/mmol (P=0.044). There was a negative correlation between duration of diabetes and UCPCR. Among all patients, it was determined that 26 (93%) had UCPCR≥0.2 nmol/mmol, whereas 16 (57%) had UCPCR≥0.7 nmol/mmol.
Conclusions: It was determined that UCPCR values might change in relationship with MODY type and diabetes duration. It was observed that, in the differential diagnosis of MODY, if UCPCR >0.7 nmol/mmol is used only 57% of patients could be defined and if UCPCR >0.2 nmol/mmol is used 93% of patients could be defined. It was deduced that an interpretation of UCPCR alongside other clinical and laboratory tests defined for MODY would strengthen the diagnosis.
20 - 22 Sep 2014
European Society for Paediatric Endocrinology