Center for Prostate Cancer, National Cancer Center, Goyang, Korea.
Urology. 2013 Nov;82(5):1059-64. doi: 10.1016/j.urology.2013.05.056. Epub 2013 Sep 14.
To confirm the hypothesis that nuclear matrix protein 22 (NMP22) is overestimated in concentrated urine, we compared the NMP22 values measured at different dietary states.
We retrospectively reviewed 531 healthy subjects who had had abnormal urinary NMP22 values ≥ 10 U/mL at the first test and underwent a second NMP22 test within 2 weeks. The first NMP22 test was performed after overnight fasting, and the second was performed with no dietary restrictions. We compared the NMP22 values between the 2 measurements and investigated the relationship between the NMP22 value and urine specific gravity.
At the second test, 504 subjects (94.9%) had a normal NMP22 value of <10 U/mL and only 27 subjects (5.1%) persistently had an abnormal NMP22 value of ≥ 10 U/mL. Both NMP22 and urine specific gravity at the first test were significantly higher than at the second test (P <.0001). Subjects with an abnormal NMP22 value tended to have a more concentrated urine with a greater urine specific gravity than did the subjects with a normal NMP22 value. This difference was significant in the subgroup undergoing bowel preparation for colonoscopy (P <.001).
NMP22 will be overestimated in concentrated urine after overnight fasting. When interpreting the NMP22 value, we should consider the overestimation of NMP22 in concentrated urine.
为了证实核基质蛋白 22（NMP22）在浓缩尿液中被高估的假说，我们比较了不同饮食状态下测量的 NMP22 值。
我们回顾性分析了 531 例首次检测尿 NMP22 值异常（≥10U/mL）且在 2 周内进行第二次 NMP22 检测的健康受试者。第一次 NMP22 检测在隔夜禁食后进行，第二次检测无饮食限制。我们比较了两次检测的 NMP22 值，并研究了 NMP22 值与尿比重之间的关系。
在第二次检测中，504 例（94.9%）受试者的 NMP22 值<10U/mL 正常，仅 27 例（5.1%）受试者持续存在 NMP22 值≥10U/mL 的异常。第一次检测时的 NMP22 值和尿比重均明显高于第二次检测（P<0.0001）。NMP22 值异常的受试者尿液比重大，尿液浓缩程度高于 NMP22 值正常的受试者。行结肠镜肠道准备的亚组中，这种差异具有统计学意义（P<0.001）。
禁食一夜后，浓缩尿液中的 NMP22 值会被高估。在解释 NMP22 值时，我们应考虑浓缩尿液对 NMP22 值的高估。
