Korean Journal of Nephrology 1989;8(3):467-472.

상부와 하부 요로감염에서 뇨 B2 - Microglobulin 치의 의의

황창희 , 김병길

Abstract

B-microglobulin is a small protein with a molecurlar weight 11,800 dalton. It is synthesized by most nucleated cells, and is present on their surfaces. It passes easily through the glomerular membrane and almost complete- ly reabsorbed in the proximal tubules of the kidney where it is metabolized. Therefore B-microglobulin excretion is increased in disorders affecting the prox- imal tubules. Since there is tubular involvement in upper urinary tract infection, urinary excretion of B-microg- lobulin is expected to increase in upper urinary tract infection. To distinguish between upper and lower urinary tract infection, the author measured the urinary excretion and renal clearance of B-microglobulin. The patients with upper urinary tract infection was 11 and the patients with lower urinary tract infection was 12, who were admitted at Severance Hospital, Yonsei University College of Medicine from November 1987 to July 1988. As a control, 7 healthy individual without renal dis- ease, malignance and autoimmune disease were also investigated. The results were as follows. 1) In patients with upper urinary tract infection, the serum B-microglobulin level was 3.27±2.39 mg/1 and the 24 hr urinary excretion of B-microglobulin was 3. 74±7.89 mg/24hr, both of which were significantly increased over those of the lower urinary tract infection (1.83±0.41 mg/I, 0.08±0.05 mg/24 hr). 2) There was no overlap of B-microglobulin excre- tion values between patients with upper urinary tract infection and those with lower urinary tract infection. From these results, it can be suggested that measure- ment of urinary excretion of B-microglobulin is a non-invasive and specific method to distinguish between upper and lower urinary tract infection.