Background: Diabetic nephropathy (DN) is a significant and enduring consequence of diabetes, and it is the primary cause of end-stage renal disease (ESRD). The objective of this research was to investigate the capability of urine aquaporin-5 (AQP-5) as a diagnostic marker for DN.
Methods: This present research was done on 80 subjects aged over 25 years old, 20 apparently healthy volunteers and 60 patients with diabetes mellitus (DM). Subjectswere categorized into 2 groups: Group I: 20 apparently healthy individuals (9 males and 11females) as control group with an age ranged from 28 to 65 years. Group II: 60 patients with DM, were subdivided into equal groups: Group IIA: patients without nephropathy with their ages ranged from 26 to 70 years and Group IIB: patients with nephropathy with their ages ranged from 34 to 77 years.
Results: ROC curve between group-IIB and group (I+IIA) according to level of urine AQP5 (ng/mL) with Cut off value >1.2ng/mL, sensitivity = 53.33%, specificity = 94%, positive predictive value (PPV) =84.2%, negative predictive value (NPV) = 77% and area under curve (AUC) 0.744. ROC curve between group (I+IIA) and group-IIB, as regard urine AQP5/creatinine ratio (ng/g) with Cut off value >1095.7 ng/g, sensitivity = 63.33%, specificity = 90%, PPV=79.2%, NPV = 80.4% &AUC= 0.807.There were significant positive correlations of urine AQP5/creatinine ratio with duration of DM (r = 0.665, P-value <0.001), HbA1C% (r = 0.442,P-value =0.014), serum creatinine (r = 0.583, P-value = 0.001), BUN (r = 0.751, P-value <0.001), ACR (r = 0.672, P-value<0.001), and urine AQP5 (r = 0.814, P-value <0.001).
Conclusions: The urine AQP5/creatinine ratio may serve as a potential non-invasive biomarker for the diagnosis and prognosis of DN.
