尿中逸脱酵素・蛋白に関する研究 第2報: 糸球体炉過機能と尿中逸脱酵素・蛋白の関係について

Abstract

慢性糸球体腎炎36例, 前立腺肥大症24例, 糖尿病性腎症6例, 腎盂腎炎8例, 計74例を対象とし, 腎糸球体濾過機能を表すとされている血中β2 microglobulin (SBMG)値と, 尿細管障碍の評価に有用とされている尿中逸脱酵素・蛋白(N-Acetyl-β-D-glucosaminidase (NAG), β2 microglobulin (β2 MG), α1 microglobulin (α1 MG)測定値を比較, 検討した.SBMGが高値を示すに伴ってNAG, β2 MG, β1 MGも高値を示したが, それを仔細に分析すると, 糸球体濾過機能障碍に伴う尿細管機能障碍の評価としては尿中α1 MG>NAG>β2 MGの順に有用であり, かつそれら単独よりも尿中α1 MGとNAGの組合わせの方が更に有用であった

Urinary splitting enzymes and proteins including N-acetyl-b-D-glucosanimidase (NAG), beta 2 microglobulin (beta 2MG), and alpha 1 microglobulin: (alpha 1MG), which are established to be useful in the evaluation of renal dysfunction, especially renal tubular impairment, were measured to determine the extent of renal tubular impairment in relation to the degree of glomerular dysfunction in patients with renal deterioration. In healthy volunteers, urinary NAG, alpha 1MG and beta 2MG levels were 3.5 +/- 1.4 (mean +/- SD) U/g creatinine, 2.5 +/- 2.0 mg/l and 88 +/- 75 micrograms/l, respectively. While serum beta 2MG level (SBMG; microgram/ml) was between 2.0 and 2.9, among the patients with renal dysfunction, NAG, alpha 1MG and BMG levels showed 8.6 +/- 5.5, 9.8 +/- 5.8 and 785 +/- 1, 264, respectively, and further elevated to 10.1 +/- 5.0, 16.5 +/- 0.7 and 525 +/- 440, respectively with a SBMG level over 3.0. Thus glomerular function was deteriorated, urinary alpha 1MG level elevated to significantly higher with a parallel to renal dysfunction. In patients with more severe renal dysfunction, the corresponding urinary NAG and alpha 1MG levels became significantly higher. However, urinary beta 2MG level was significantly higher in patients with moderate renal dysfunction compared to healthy volunteers only when SBMG level was more than 2.0. Therefore, it was more valuable to measure urinary alpha 1MG with NAG or beta 2MG at SBMG level of less than 1.9 and to determine urinary NAG and alpha 1MG at greater than 2.0. These results indicated that the measurement of the levels of urinary splitting enzymes and proteins is valuable in the evaluation of proximal tubular impairment, even when the degree of glomerular impairment is minimal.(ABSTRACT TRUNCATED AT 250 WORDS)