Urinary N-Acetyl-β-d-glucosaminidase (uNAG) as an Indicative Biomarker of Early Diabetic Nephropathy in Patients with Diabetes Mellitus (T1DM, T2DM): A Systematic Review and Meta-Analysis

Abstract

Diabetic nephropathy (DN) is the main cause of chronic kidney disease in patients with type 1 (T1DM) and type 2 diabetes mellitus (T2DM). Renal tubular lysosomal enzyme activities like N-acetyl-β-d-glucosaminidase (NAG) have been shown to increase in patients developing DN. The aim of this systematic review and meta-analysis is to evaluate the diagnostic accuracy of NAG, as a preventional biomarker in the early stages of DN in patients with diabetes mellitus. Two impartial reviewers conducted a complete PubMed search until July 2021. A 2 × 2 contingency table was created for each trial and sensitivity and specificity were estimated using a bivariate random effects model. To pool data and estimate the area under the curve (AUC), the hierarchical summary ROC (hsROC) approach was utilized. Deek’s test was used to estimate publication bias. The meta-analysis included 21 studies that evaluated 2783 patients with T1DM and T2DM, as well as 673 healthy individuals. The AUC of urinary NAG (uNAG) ranged from 0.69 (95% CI: 0.65–0.73) to 0.89 (95% CI: 0.86–0.92). According to the results, NAG in urine can be considered as a potential and effective biomarker for predicting DN in diabetic patients (T1DM, T2DM).