小児の尿路感染症の部位診断における尿中LDHアイソザイム分析の有用性

Abstract

Clinical differentiation between pyelonephritis and cystitis is often difficult to determine in infants and children. Precise localization of the site of infection is important from a therapeutic and prognostic standpoint in children with urinary tract infection (UTI). The present investigation was undertaken to determine whether or not urinary lactic dehydrogenase (LDH) isoenzyme analysis could be available for differentiation between upper UTI and lower UTI. Fourteen children 2 months to 15 yr of age constituted the subjects for the study. Urinary LDH isoenzyme analyses were performed using cellulose acetate membrane electrophoresis. On the basis of the patterns of urinary LDH isoenzymes, patients were divided into two groups. Of 14 patients, 10 (group I) showed predominant elevations of LDH1 and LDH2 (fast zone pattern) in the urine. In the remaining four (group II), urinary LDH predominantly consisted of LDH4 and LDH5 (slow zone pattern). Clinical findings revealed that body temperatures were significantly higher in group II than in group I. Laboratory findings showed that the serum levels of C-reactive protein (CRP) and urinary levels of β2 microglobulin were slgnificantly higher in group II than in group I. Therefore, patients in group I were compatible with lower UTI and patients in group II with pper UTI. This study shows the urinary LDH isoenzyme analysis to be useful for differentiation between upper UTI and lower UTI in children.