Diabetes mellitus is the commonest cause of ESRD worldwide and third most common cause in Nigeria. Recent reports from Nigeria indicate the prevalence of diabetic nephropathy as an aetiology of ESRD is increasing necessitating early diagnosis of diabetic nephropathy. We measured the urinary excretion of N-acetyl-beta-D-glucosaminidase (NAG), NAG/creatinine ratio, urinary protein-creatinine ratio and calculated eGFR in 30 recently diagnosed nonhypertensive diabetics and 67 controls. The age and sex distribution, systolic blood pressure, serum and urinary creatinine were similar for both groups. There was higher urinary excretion of NAG (304 versus 184？μmol/h/L, ？？ < 0 . 0 0 1 ) and NAG/creatinine ratio (21.2 versus 15.7？μmol/h/L/mmolCr, ？？ < 0 . 0 0 1 ) in the diabetics than controls. There was a strong correlation between NAG/creatinine ratio and albumin/creatinine ratio ( ？？ = 0 . 7 4 , ？？ < 0 . 0 0 1 ). A multivariate linear regression model showed a significant linear relationship between NAG/creatinine ratio and albumin/creatinine ratio after adjusting for the effect of blood pressure, age, sex, and serum creatinine. The strong association found between albumin/creatinine ratio and NAG/creatinine ratio perhaps indicates the need for further investigation of the clinical utility of NAG/creatinine ratio as a screening tool for early nephropathy in African diabetics. 1. Introduction End-stage renal disease is on the increase worldwide. However, it is difficult to appropriately compare international data on the aetiology, incidence, and prevalence because of differences in how data for various registries are derived, different patient demographics, and quality of healthcare among others. Diabetes mellitus (DM) is still recognized in the US and Europe as the commonest cause of end-stage renal disease (ESRD). Indeed recent data from the US Renal Data System suggests that the rates of ESRD due to DM and hypertension rose by 2.2% and 2.7%, respectively, in 2009 with overall prevalent ESRD estimated at 1,738 per million population [1]. African Americans were in the majority. Reports from Europe and Asia have also shown a rise in the incidence of ESRD over the years [2–4]. In Nigeria, many hospital-based reports put diabetic nephropathy as the third most common cause of ESRD [5–7], but it appears that the proportion of ESRD caused by diabetic nephropathy is increasing [8]. In the last two decades, studies have focused on the role of glomerular injury in early diabetic nephropathy (as measured by the onset of persistent microalbuminuria), but attention is now
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