Abstract 16: Urinary metabolic signatures for differential diagnosis of diabetic and non-diabetic kidney disease

BACKGROUND: Renal involvement in T2DM can be due to diabetes per se (Diabetic Kidney Disease) or causes other than diabetes (Non-diabetic kidney disease). Currently available clinical, biochemical and radiological markers fail to differentiate DKD from NDKD and renal biopsy remains gold standard for correct diagnosis. While urinary signatures may provide a non-invasive alternative to that end, no study has been reported on urinary metabolomics of biopsy-confirmed DKD and NDKD subjects. AIMS: To identify the expression of urinary metabolic signatures as putative marker for differentiation of biopsy-confirmed DKD and NDKD subjects. METHODS: Consecutive patient with renal involvement were subjected to biopsy and classified as per ISN/RPS Classification. Morning urine sample were collected for analysis by Gas Chromatography and mass spectrometry. Features were extracted and analysed using appropriate statistical method. RESULTS: Urinary metabolites (M1, M2, M3, M4) were found to be depleted in patients with kidney disease (P < 0.004, <0.006, and < 0.01, <0.03 respectively). M5 was exclusively depleted in NDKD (n=16). The level of M6 (<0.01), M7 (<0.03) increased and M8 (<0.05), M9 (0.03), M10 (0.02) were decreased in DKD subjects (n=34) . CONCLUSION: Our pilot study suggests that urinary metabolomics analysis may help to distinguish DKD and NDKD subjects. Our results warrant validation in another cohort.