Fliedner M, Mehls O, Rauterberg E W, Ritz E
J Pediatr. 1986 Sep;109(3):416-21. doi: 10.1016/s0022-3476(86)80110-x.
Urinary secretory IgA (sIgA) was measured using a specific ELISA with insolubilized anti-IgA and enzyme-linked antisecretory component. This test was applied to unprocessed urine from healthy children and from children with urinary tract infection. Normal range was a function of age. In 175 healthy children the excretion rate of sIgA was low in infants younger than 6 months but was constant between ages 6 months to 15 years (median 0.69 mg/gm creatinine, range 0.15 to 3.4 mg/gm creatinine), whereas sIgA concentration (milligrams per liter of urine) increased continuously with age. No sex difference was noted. There were no significant circadian changes or day-to-day variability. Thirty girls, age 1 to 16 years, were examined; they had a history of recurrent symptomatic episodes of urinary tract infection but had anatomically normal tracts and no symptoms, and no bacteriuria at the time of study. sIgA excretion rate was significantly lower (0.45 mg/gm, creatinine, 0.08 to 0.75 mg/gm creatinine) than in controls. In contrast, 11 girls examined at the time of symptomatic urinary tract infections, and who had normal urinary tracts, had significantly (P less than 0.01) higher sIgA excretion rates (1.4 mg/gm creatinine, 0.8 to 3.4 mg/gm creatinine) than those in either control subjects or girls without symptoms at the time of study. Urinary sIgA excretion rates were highest (2.0 mg/gm creatinine, 0.44 to 3.69 mg/gm creatinine) in children with symptomatic urinary tract infections who had an abnormal urinary tract. We conclude that low urinary sIgA values may be a marker for recurrent symptomatic bacteriuria in girls with normal urinary tracts.
采用固相抗IgA和酶联抗分泌成分的特异性酶联免疫吸附测定法（ELISA）检测尿分泌型IgA（sIgA）。该检测方法应用于健康儿童和尿路感染患儿的未处理尿液。正常范围因年龄而异。在175名健康儿童中，6个月以下婴儿的sIgA排泄率较低，但在6个月至15岁之间保持恒定（中位数为0.69mg/g肌酐，范围为0.15至3.4mg/g肌酐），而sIgA浓度（每升尿液中的毫克数）则随年龄持续增加。未发现性别差异。未观察到明显的昼夜变化或每日波动。对30名年龄在1至16岁的女孩进行了检查；她们有复发性有症状尿路感染发作史，但尿路解剖结构正常，在研究时无症状且无细菌尿。sIgA排泄率显著低于对照组（0.45mg/g肌酐，0.08至0.75mg/g肌酐）。相比之下，11名在有症状尿路感染时接受检查且尿路正常的女孩，其sIgA排泄率（1.4mg/g肌酐，0.8至3.4mg/g肌酐）显著高于（P<0.01）对照组或研究时无症状的女孩。有症状尿路感染且尿路异常的儿童尿sIgA排泄率最高（2.0mg/g肌酐，0.44至3.69mg/g肌酐）。我们得出结论，尿sIgA值低可能是尿路正常女孩复发性有症状菌尿的一个标志物。
