【摘要】 目的 探讨尿N-乙酰--D-氨基葡萄糖苷酶(N-acecyl--D-glucosaminidase,NAG)/尿肌酐(creatinine，Cr)的在老年重症肺炎急性肾损伤患者中的诊断意义。方法 回顾分析19例老年重症肺炎合并急性肾损伤患者(试验组)的尿NAG/Cr的变化情况，患病前后48 h、第7 d的血肌酐应用生化分析仪检测，尿NAG/Cr用速率散射法检测。对照组为同期住院不伴有肺部感染的19例非肾脏疾病患者。结果 试验组患病前与对照组比较，血Cr及尿NAG/Cr差异无统计学意义(P＞0.05)；根据急性肾损伤网络(Acute Kidney Injury Network,AKIN)的标准，患重症肺炎后48 h诊断急性肾损伤Ⅰ期15例，Ⅱ期3例，Ⅲ期1例；合并急性肾损伤的患者尿NAG/Cr均明显增高。患重症肺炎后的第7 d，检测了尿NAG/Cr的12例患者中的5例肾衰竭患者尿NAG/Cr明显高于已好转的另7例非肾衰竭患者。结论 尿NAG/Cr的增高对老年重症肺炎合并急性肾损伤有诊断意义。

【Objective】 To investigate the value of urinary N-acety-β-D-glucosaminidase (NAG)/creatinine (Cr) ratio for the early diagnosis of acute kidney injury (AKI) in elderly patients with severe community-acquired pneumonia (CAP). Methods We retrospectively analyzed the changes of urinary NAG/Cr ratio in 19 elderly patients with severe CAP and AKI. We also analyzed the ratio in 19 elderly people without renal disease and pneumonia as controls. Urinary NAG and Cr were measured before AKI and after the presence of AKI for 48 hours and 7 days. NAG was assayed by spectrophotometry, and urinary Cr by biochemistry method on automatic analyzer. Results In the 19 patients after presence of AKI for 48 hours, 15 cases were identified as stage I AKI, 3 cases as stage II, and one case as stage III AKI, based on the criteria from the Acute Kidney Injury Network (AKIN). In elderly patients with severe CAP after presence of AKI for 48 hours, urinary NAG/Cr ratio was significantly higher than that before the presence of AKI (P<0.01). In the 12 elderly patients with severe CAP after presence of AKI for 7 days, urinary NAG/Cr ratio was significantly lower in the 7 patients recovering from AKI than the 5 patients having acute renal failure. Conclusion Urinary NAG/Cr ratio may be useful for the early diagnosis of AKI in elderly patients with severe CAP.