Distribution of urinary N‐acetyl‐beta‐D‐glucosaminidase and the establishment of reference intervals in healthy adults

Abstract

Background Urinary N‐acetyl‐beta‐D‐glucosaminidase (NAG) plays an important role in the early diagnosis and progression of diseases related to renal tubular injury. We detected the urinary NAG concentration, assessed the preliminary statistics of its distribution, and established reference intervals for healthy adults in China using the rate method. Methods A total of 1,095 reference individuals (aged 20 to 79 years) met the requirements for inclusion in this study. Urinary NAG concentrations were detected using an AU5800 automatic biochemical analyzer with its matched reagents. The Kolmogorov‐Smirnov test was used to analyze the normality of the data. According to the guidelines of C28‐A3 and WS/T 402‐2012, the reference intervals of urinary NAG were established using the nonparametric percentile method (unilateral 95th percentile). Results The urinary NAG data showed a non‐normal distribution. The distribution of urinary NAG was significantly different by sex and age. Therefore, the reference intervals of urinary NAG were established using the rate method: males (aged 20–59 years) <19.4 U/L (90% CI: 18.0–20.3 U/L); males (aged 60–79 years) <22.3 U/L (90% CI: 20.2–22.6 U/L); females (aged 20–59 years) <15.7 U/L (90% CI: 15.2–16.5 U/L); and females (aged 60–79 years) <21.4 U/L (90% CI: 20.3–22.3 U/L). Conclusions We established preliminary reference intervals of urinary NAG for healthy adults in China to provide guidance for health screening, auxiliary diagnosis, and treatment monitoring of renal tubule‐related diseases.

Nephrotoxic Biomarkers with Specific Indications for Metallic Pollutants: Implications for Environmental Health

“…43 A rate procedure has recently been described to determine reference ranges for NAG in healthy Chinese adults. 46 …”

Electrochemical N-Acetyl-β-D-glucosaminidase Urinalysis: Toward Sensor Chip-Based Diagnostics of Kidney Malfunction

“…B plots of the anodic 4NP peak current magnitudes, ip, as a function of the GlcNAc centration and trial time, t, show the marked difference between the voltammetr Lysosomal GlcNAcase in circulating blood is too large to pass through the filtration system of the renal glomeruli into the urine; however, it might enter urine in tiny amounts by, for instance, lysosomal exocytosis. The urine of healthy people with normal kidney function is thus not entirely free of GlcNAcase, but its level is low with 5-10 U/L having been reported for control populations in clinical studies [36,37]. The elevated and critical levels are 20 and 100 U/L or higher, respectively.…”

Associations Between Characteristics of Individuals With Fontan Circulation With Blood and Urine Biomarkers of Kidney Injury and Dysfunction

“…Existing literature was used to determine the cutoff for elevated NGAL (>50 ng/mL), KIM‐1 (>1300 pg/mL), and NAG (>18 U/L). 12 , 13 , 14 The McNemar test was used to compare the percentages of CKD defined by creatinine eGFR and cystatin eGFR. The Student t ‐test was used to compare normally distributed continuous variables between 2 groups; for nonnormally distributed continuous variables, the Wilcoxon rank sum test was used.…”