尿N-乙酰-β-D-氨基葡萄糖苷酶水平与新生儿窒息后肾损伤关系

目的探讨新生儿窒息后尿 N-乙酰-β-D-氨基葡萄糖苷酶（N-acetyl-beta-D-glu-cosaminidase,NAG）、血清中α1微球蛋白（α1-microglobulin,α1-MG）、β2-MG 值水平变化以及与窒息程度和急性肾损伤（acute kidney inj ury,AKI）之间的关系,阐述其在窒息新生儿肾损伤中的诊断价值。方法选择围产期窒息新生儿40例（窒息组）,按照新生儿窒息Apgar评分标准分为轻度窒息者22例（轻度窒息组）,重度窒息者18例（重度窒息组）；根据有无发生 AKI 将40例窒息新生儿分为AKI组25例和无 AKI组15例；记录入选新生儿 Apgar评分、胎龄、日龄、体质量。另外选择20例无窒息史新生儿为对照组。所有纳入对象在出生后24 h内采取外周静脉血,同时收集尿液。采用胶乳增强免疫比浊法测定血清中α1-MG、β2-MG的含量；采用 ELISA法测定尿液中 NAG含量；同时用全自动生化仪检测尿素氮及血肌酐水平。结果（1）本研究40例窒息后新生儿 AKI 总发生率为62.5%（25/40）,并且轻度窒息与重度窒息对 AKI 影响不同,重度窒息患儿更易发生严重的肾损伤。（2）窒息组尿 NAG及血清中β2-MG、α1-MG明显高于对照组（25.48±12.45）U/L 比（8.62±2.49） U/L,（4.82±1.32）mg/L比（2.92±0.89）mg/L,（29.85±5.59）mg/L 比（25.23±5.26）mg/L]。（3）重度窒息组尿 NAG及血清中β2-MG、α1-MG 明显高于轻度窒息组（32.21±24.32）U/L、（5.89±1.59）mg/L、（34.32±7.64）mg/L]明显高于轻度窒息组（17.25±7.32）U/L、（2.92±0.89）mg/L、（26.94±5.57）mg/L]。（4）AKI组尿 NAG及血清中β2-MG、α1-MG（28.24±21.25）U/L、（5.79±1.49）mg/L、（31.32±5.28）mg/L]明显高于无 AKI组（16.34±6.72））U/L、（2.82±0.79）mg/L、（26.49±5.52）mg/L]。（5）按照对照组尿 NAG及血清中β2-MG、α1-MG值设定在x＋2SD为对照上限值,窒息组中尿 NAG异常率达65%,明显高于血清中β2-MG、α1-MG 异常率（分别为32.5%和7

Correlation between urinary NAG levels in neonates and asphyxia-induced acute kidney injury

Objective To study urine levels of N-acetyl-β-D-glucosaminidase （NAG）,serum levels ofα1-microglobulin （MG）andβ2-MG and their association with acute kidney inj ury （AKI）and asphyxia severity in neonates with asphyxia.Methods Forty cases of neonatal asphyxia were divided into mild asphyxia group （22 cases）and severe asphyxia group （18 cases）according to APGAR scores,and AKI group （25 cases）and non-AKI group （1 5 cases）according to the definition of AKI. Twenty neonates without perinatal asphyxia served as control group.Apgar score,gestational age, day age and body weight were recorded.Peripheral blood was obtained within 24 h in all cases after birth.Serumα1-MG andβ2-MG concentrations were measured by latex-enhanced immunoassay,and urine NAG by ELISA simultaneously.Results The incidence of AKI was 62.5% in neonatal asphyxi-a,and severe asphyxia was more likely leading to more serious kidney inj ury.Urine NAG,and serumβ2-MG andα1-MG levels were （25.48±12.45）U/L,（4.82±1.32）mg/L and （29.85±5.59）mg/L in asphyxia group respectively,which were significantly higher than those in normal control group （8.62±2.49）U/L,（2.92±0.89）mg/L and （25.23±5.26）mg/L].Urine NAG,and serumβ2-MG andα1-MG levels in severe asphyxia group were （32.21±24.32）U/L,（5.89±1.59）mg/L and （34.32±7.64）mg/L respectively,which were significantly higher than those in the mild asphyxia group （17.25±7.32）U/L,（2.92±0.89）mg/L and （26.94±5.57）mg/L].Urine NAG,and ser-umβ2-MG andα1-MG levels in AKI group were （28.24±21.25）U/L,（5.79±1.49）mg/L and （31.32± 5.28）mg/L respectively,which were significantly higher than those in non-AKI group （16.34±6.72）U/L,（2.82±0.79）mg/L and （26.49±5.52）mg/L].The percentage of abnormal-ly increased urine NAG in asphyxia group was 65%,significantly higher than that of serumβ2-MG （32.5%）andα1-MG （7.5%）（P〈0.01）.Conclusions The incidence of AKI among neonates with asphyxia was 62.5%,and severe