[Early diagnosis of renal ischemia in arterial hypertension by means of urine N-acetyl-beta-D-glucosaminidase (author's transl)].

Essential arterial hypertension, malignant hypertension and renovascular hypertension were studied in 64 patients, divided into 5 groups according to creatinine clearance (Ccreat) and ophthalmic fundus. Urine N-Acetyl-b-d-glucosaminidase (NAG) was expressed in units/mg creatinine in urine. Results were; Group A: Ccreat greater than 60, ophthalmic fundus less than II (n=33), NAG 13.5 + 4.5; Group B: CCreat. greater than 60, ophthalmic fundus III-IV (n=4) NAG 42.4 +/- 12.5; Group C: Ccreat. less than 60, ophthalmic fundus less than II (n = 14) NAG 31.2 +/- 10,5; Group D: (clinically malignant arterial hypertension) Ccreat. less than 60, ophthalmic fundus III--IV (n = 8), NAG 91.1 +/- 55.7 and Group E: (renovascular hypertension) Ccreat. greater than 60, ophthalmic fundus less than II (n = 5), NAG 35.5 +/- 12.9. Only the patients in Group A had NAG within normal limits. Differences were found between groups: A-B (p less than 0.001), A-D (p less than 0.001), A-E (p less than 0.001) and C-D (p less than 0.001). Urine NAG is considered to be an early sign of renal involvement in arterial hypertension, an indication of the severity and a sign of ischemia even when the involvement is unilateral only, and helpful in the management of renovascular hypertension.