Expression modes of urinary N-acetyl-beta-D-glucosaminidase in patients with chronic renal insufficiency.
BACKGROUND
Urinary N-acetyl-beta-D-glucosaminidase (NAG) activity has emerged as potentially useful early marker of renal tubular injury. This activity is usually evaluated in random urine samples and is related to urinary creatinine concentration. Reports about the lack of correlation between NAG activity of 24-h urines and activity of random urine samples in some clinical and experimental situations led us to study the correlation existing between different procedures for expressing urinary NAG in patients with chronic renal insufficiency.


METHODS
Thirty samples of 24-h urine and 30 random urine samples from chronic renal insufficiency patients were collected. The activity of urinary NAG was examined fluorimetrically.


RESULTS
The following correlations were observed: (1) r = 0.431 (P = 0.017) for activity in random urine samples and total activity in 24-h urines); (2) r = 0.281 (P = 0.005) for activity in random samples and activity, expressed as U/l, in 24-h urines.


CONCLUSIONS
The data show that collection of urine excreted over the whole day and evaluation of total daily excretion of NAG seems the method of choice, at least for patients with chronic renal insufficiency.
Tassi
C
C
Dipartimento di Scienze Biochimiche e Biotecnologie Molecolari, Università degli Studi di Perugia, Via del Giochetto, 6100 Perugia, Italy.
Mancuso
F
F
Feligioni
L
L
Marangi
M
M
Capodicasa
E
E
D000118:Acetylglucosaminidase / Q000652:urine*; D000328:Adult; D015415:Biomarkers / Q000652:urine; D005260:Female; D005470:Fluorometry; D006801:Humans; D007674:Kidney Diseases / Q000175:diagnosis / Q000201:enzymology / Q000652:urine*; D007676:Kidney Failure, Chronic / Q000175:diagnosis / Q000201:enzymology / Q000652:urine*; D007677:Kidney Function Tests / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011897:Random Allocation; D013048:Specimen Handling
D015415:Biomarkers; D000118:Acetylglucosaminidase