CLINICAL AND DIAGNOSTIC-SIGNIFICANCE OF DETERMINATION OF MICROALBUMINURIA AND ACTIVITY OF TUBULAR ENZYME N-ACETYL-BETA-D-GLUCOSAMINIDASE (NAG) IN PATIENTS WITH HYPERURICOSURIA

Aim. Development of the approaches to detection of hyperuricosuric sta ge of purin metabolism derangement and specification of methods for ea rly diagnosis of urate damage to the kidney. Materials and methods. Th e study included 115 young subjects whose parents suffer from gout wit h renal involvement or isolated urate nephropathy. Each patient Mas ex amined clinically with evaluation of family history for gout risk fact ors. Three times for 9 months measurements were made of uricemia and u ricosuria, microalbuminuria and activity of tubular enzyme NAG. Result s. 45 (39.1%) patients had neither disturbances of purin metabolism no r renal affection. 70 (60.9%) patients had hyperuricosuria. In 23 (32. 9%) of them microalbuminuria increased to >20 mg/day, NAG activity to 5 u/l. Chronic tubulointerstitial nephritis was diagnosed in 17 (73.9% ) patients. Six patients (26.1%) developed asymptomatic affection of t he kidneys. The rest 47 patients had normal levels of microalbuminuria find NAG. There were 3 cases of hyperuricemia with microalbuminuria r ising to 160-200 mg/day and further development of urinary syndrome. H yperuricemia in them was registered at microalbuminuria higher that 16 0 mg/day. Conclusion. Microalbuminuria higher than 20 mg/day and NAG a ctivity higher than 5 u/day are important diagnostic indicators of ren al affection in hyperuricosuria asymptomatic one. Microalbuminuria abo ve 160 mg/day gives grounds to discuss the role of morphological chang es prior to proteinuria.