Sakai Naoshi, Fuchigami Hiroshi, Ishizuka Tsuneo, Tanaka Takahisa, Kato Masayuki, Nakamura Tsutomu, Nakayama Keiji, Kawaguchi Rieko, Kuroda Yutaka, Munakata Hiromi, Noda Mitsuhiko, Kakei Masafumi, Matsumoto Masahiko
Minaminakamaru Clinic, 1078-3 Minaminakamaru, Minuma-ku, Saitama City, Saitama 337-0041, Japan.
Tokai J Exp Clin Med. 2019 Dec 20;44(4):118-123.
Proteinuria is a marker for cardiovascular diseases and all-cause mortality. In the Specific Health Checkups in Japan, when subjects show trace proteinuria (grade±) on dipstick assay, further examination is recommended to them. Although 150 mg/gCr is a threshold for diagnosing chronic kidney disease (CKD), little data on the relationship between dipstick grade± and the protein-creatinine ratio have been reported.
A cross-sectional study using urine specimens obtained in a single institute, JCHO Saitama Northern Medical Center, was performed from October 2014 to March 2016. The level of proteinuria was measured in fresh morning urine samples from 819 volunteer participants of the Specific Health Checkups by two methods: Eiken Uropaper III to detect and qualitatively grade proteinuria, and total protein concentration by the pyrogallol red method.
Sensitivity, specificity, and the positive likelihood ratio to detect proteinuria of 30 mg/dL by 1+ were 90.3%, 97.8%, and 41.9, whereas 150 mg/gCr by ± were 45.3%, 81.4%, and 2.4, respectively. Therefore, screening for 150 mg/gCr by dipstick grade± had a false-negative rate of 54.7% and false-negative rate was significantly higher in women (8.0%) than in men (1.7%) (p < 0.0001).
Although the dipstick assay is useful to detect clinically significant proteinuria, substantial numbers of false-negative results occur in checkups for identifying subjects with a risk of CKD.
蛋白尿是心血管疾病和全因死亡率的一个标志物。在日本的特定健康检查中，当受试者在试纸法检测中显示微量蛋白尿（±级）时，建议对其进行进一步检查。虽然150mg/gCr是诊断慢性肾脏病（CKD）的阈值，但关于试纸法±级与蛋白肌酐比值之间关系的数据报道较少。
2014年10月至2016年3月，在埼玉北医疗中心（JCHO Saitama Northern Medical Center）这一单一机构进行了一项横断面研究，该研究使用所采集的尿液标本。通过两种方法对特定健康检查的819名志愿者参与者的清晨新鲜尿液样本中的蛋白尿水平进行测量：使用荣研尿试纸III检测并对蛋白尿进行定性分级，以及使用邻苯三酚红法检测总蛋白浓度。
用+1检测蛋白尿水平为30mg/dL时的灵敏度、特异度和阳性似然比分别为90.3%、97.8%和41.9，而用±检测蛋白尿水平为150mg/gCr时分别为45.3%、81.4%和2.4。因此，通过试纸法±级筛查150mg/gCr时假阴性率为54.7%，且女性（8.0%）的假阴性率显著高于男性（1.7%）（p<0.0001）。
虽然试纸法检测对于检测具有临床意义的蛋白尿是有用的，但在筛查具有CKD风险的受试者的检查中会出现大量假阴性结果。
