Unveiling the Continuum: Tracking Urinary Transforming Growth Factor (TGF)-β1 in Diabetic Nephropathy Follow-Up

Background: Diabetic nephropathy (DN) is a leading cause of end-stage kidney disease (ESKD). Accumulating evidence points to transforming growth factor beta-1(TGF-β1),a potent profibrotic mediator, as a significant mediator in the development of DN. Methods: It was a prospective observational study including 10 cases of diabetic Nephropathy in group A and 10 healthy controls in group B, age ≥ 18 years. Patients with urinary tract infection, pregnancy, CKD stage Vd patients on maintenance hemodialysis and post renal transplant cases were excluded.Patients clinical characteristics and examination findings were recorded at visit 1 and follow up after 3 months (visit 2). Patients received standard of care treatment during the follow up. Urinary TGF-β1 levels were determined in a 24 hours urine sample using Miltenyi-MACSQuant-10 flowcytometer, each sample run in triplicates and average of the three taken. The biochemical tests were performed using dimension ExL clinical chemistry system (SIEMENS). Quality of life was assessed using Karnofsky performance status scale. Results: In group A, the mean value of urinary TGF-β1 on visit 1 was 88.33 ± 12.44 ng/24 hours and on visit 2 was 69.25 ± 13.56 ng/24 hours. The reduction in the TGF-β1 levels on follow up in group A was statistically significant (p< 0.001).The mean value in the group B was 29.03± 3.23 ng/24 hours, significantly low compared to group A (p<0.001). In group A there was no significant correlation between urinary TGF β1 levels and 24 hours urine protein, on visit 1 and 2(r = 0.341 and r=0.505) or UPCR on visit 1 and 2 (r = 0.154,p = 0.672 and r= 0.120,p= 0.742). Also, the change in urinary TGF-β1 levels(between visit 1 & 2) didn’t correlate with change in 24 hours urine protein (r=0.258, p=0.472), UPCR(r=0.240, p=0.505) or eGFR(r=-0.268, p=0.455). The median Karnofsky performance status was 80 on visit 1 and 90 on visit 2 in group A, while it was 100 in group B. Conclusion: Urinary TGF- β1 levels reduced significantly on follow up after 3 months amongst diabetic nephropathy patients but that change didn’t correlate with the change in proteinuria and eGFR.There was no significant correlation between urinary TGF- β1 levels and proteinuria, serum creatinine level or eGFR.