目的：探討化療處方範本更新後，給予高劑量 methotrexate (HDMTX) 期間常規 監測尿液 pH 值是否改善 methotrexate 排除速率、減少相關副作用發生。並評估是否 可藉由病人給藥前尿液 pH 值預測病人 HDMTX 引起急性腎損傷風險。
 

方法：此回溯性研究於 2018 年 9 月某醫學中心化療處方範本更新前後，分別收 載 117 位及 73 位使用 HDMTX 病人。透過病歷收集資料，分析常規監測尿液 pH 值 前後兩組急性腎損傷發生率、尿液檢測率、尿液 pH 值達標率 (pH ≥ 7.0) 是否統計顯 著差異。依據發生急性腎損傷與否進行次族群分析，探討兩組給藥前尿液 pH 值是否 統計顯著差異並探討危險因子。
 

結果：HDMTX 化療處方範本更新後，尿液檢測率增加 (30.8% vs. 68.5%, p < 0.0001)、尿液pH值達標率增加 (首日6.8% vs. 16.4%，p = 0.03；次日 1.7% vs. 21.9%，p < 0.0001)，急性腎損傷發生率並無統計顯著差異 (16.24% vs. 9.59%, p = 0.19)。在多變項邏輯斯迴歸分析中，給藥前尿液 pH 值低、水腫、HDMTX 劑量高、併用腎毒性藥品是 HDMTX 引起急性腎損傷的統計顯著影響因子。
 

結論：HDMTX 化療處方範本更新後，尿液檢測率及尿液 pH 值達標率皆顯著增 加，急性腎損傷發生率並無統計顯著差異。給藥前尿液pH值低是 HDMTX 引起急性腎損傷的統計顯著影響因子之一。常規監測尿液 pH 值可以讓醫療團隊及時調整尿液 鹼化處方，針對給藥前尿液pH值較低之病人，需及早提高尿液鹼化處方強度。

 

Objective: The study assessed the effect of urine pH monitoring on the side effects of high-dose methotrexate (HDMTX) therapy after a prescription template revision. We also determined whether baseline urine pH can predict the risk of HDMTX-induced acute kidney injury. 
 

Methods: This retrospective study included 117 and 73 patients who received, respectively, HDMTX therapy before and after the revision of a prescription template issued by a medical center in September 2018. We extracted data from the patients’ medical records. The incidence of acute kidney injury, rate of urine analysis, and percentage of patients with a urine pH of ≥7.0 were analyzed. On the basis of the occurrence of acute kidney injury, a subgroup analysis was conducted to determine the risk factors. 
 

Results: After the prescription template was revised, the urine analysis rate (30.8% vs 68.5%, P < 0.0001) and percentage of patients with a urine pH of ≥ 7.0 increased significantly in the first 2 days (6.8% vs 16.4%, P = 0.03; 1.7% vs 21.9%, P < 0.0001). The difference in the incidence of acute kidney injury was nonsignificant (16.24% vs 9.59%, P = 0.19). A low baseline urine pH, edema, a high methotrexate dose and concomitant nephrotoxic medication were identified as risk factors for HDMTX-related acute kidney injury. 
 

Conclusions: Urine pH monitoring helps medical team adjust their alkalization regimens in a timely manner, but does not lead to a significant difference in incidence of HDMTX-related acute kidney injury. A low baseline urine pH is a risk factor for HDMTX-related acute kidney injury. For patients with a low baseline urine pH, an intensive alkalization regimen must be administered as quickly as possible.

 

Submited for publication: 2021.7.31; Accepted for publication: 2021.12.19