Assessement of the Tubular Lesion by Determination of N-acetyl-beta-d-glucosaminidase in Surgically Acquired Single Kidney as Compared to Congenital Single Kidney Patients

Correspondence to:Dr. Gãdãlean Florica, e-mail: [email protected] SUMMARY:Background Tubular adaptive changes occurring after 50% reduction of renal mass can, in time, cause lesion to the tubular cell. According to data in the literature, the adaptive mechanisms occuring in the surgically aquired single kidney (SK) compared to those occurring in the congenital single kidney, seem to be completely different. The different compensatory adaptive changes in surgically acquired SK patients as compared to congenital SK patients may also be associated with different deleterious effects on the renal tubular cell, with different urinary enzymatic excretion. The urinary excretion of high-molecular-weight enzymes, for example urinary excretion of N-acetyl-ß-D-glucosaminidase (NAG) is a sensitive indicator of renal tubular cell damage. Aim The aim of our study was to assess the deleterious effects on the renal tubular cell due to the compensatory adaptive changes by studying the NAG biomarker in patients with surgically acquired SK as compared to those with congenital SK, at a similar moment in time of the existence of a single kidney. Patients and methods. A cross-sectional study has been performed on two groups of patients. Group A consisted from 16 patients (p) with surgically acquired single kidney. Mean/average age was 61.63 ± 11.66 and the mean time frame from nephrectomy was 30.94 ± 13 years (18-58 years). Group B consisted of 16 patients (p) with congenital single kidney. The mean/average age was 32.5 ±10.31 years (18-58 years). Results Urinary NAG for the group A had a mean value of 3.53±2.75 U/gcreat. For the group B, urinary NAG had a mean value of 4.7±6.33 U/gcreat. In both groups analyzed, we observed a strong correlation between the urinary NAG value and arterial hypertension duration (group A r=-0.745, P=0.008; group B r=0.795, P=0.010). Conclusion. The tubular compensatory adaptive phenomena occurring in the surgically acquired SK after nephrectomy are not accompanied by different tubular lesional changes from those in the congenital SK. The strong correlation between NAG activity and arterial hypertension duration underlines the usefulness of NAG monitoring in hypertensive SK patients.