目的 探讨吗替麦考酚酯（MMF）治疗儿童系统性红斑狼疮（SLE）的霉酚酸血药浓度时间曲线下面积（MPA AUC）与疾病活动、疾病复发及药物不良反应的关系。方法 回顾分析2017年1月至2019年6月行MMF血药浓度检测的 SLE患儿的临床资料。纳入患儿近半年的治疗方案为激素联合MMF、羟氯喹，MMF使用剂量为20 ~ 40 mg/（kg ·d）。根据 患儿SLE疾病活动度评分（SLEDAI）、是否复发以及有无不良反应分组，比较各组间MPA AUC水平；根据MPA AUC水平 分为3组，比较三组间疾病活动度及不良反应情况。结果 本研究共纳入81例患儿，男20例、女61例，中位年龄为13 . 1 （11.0~14.4）岁。根据SLEDAI-3个月分组，非活动组67例，活动组14例。与非活动组相比，活动组的起病年龄偏小，白蛋 白和肌酐水平较低，估算肾球滤过率较高，差异均有统计学意义（P<0.05）。非活动组随访3个月及6个月的MPA AUC0-12h 均高于活动组，差异有统计学意义（P<0 . 05）。低、中、高AUC三组之间随访3个月以及6个月后的SLEDAI评分差异均有 统计学意义（P<0.05），均以低AUC组的SLEDAI评分为较高。复发组MPA AUC水平低于未复发组，差异有统计学意义 （P= 0 . 001）。利用ROC曲线预测患儿复发时MPA AUC的截断值为43 . 03 mg/(h · L)，曲线下面积为0 . 89（P= 0 . 001），灵敏 度100 %，特异度69.8%。结论 MMF治疗儿童SLE，监测MPA AUC有重要意义。MPA AUC与疾病活动度呈负相关，血 药浓度43 . 03 mg/(h · L)以上可维持SLE在低活动度水平及减少疾病复发，过高浓度对疾病活动并无改善。

Objective To explore the relationship of the area under the mycophenolic acid concentration-time curve (MPA AUC) with disease activity, disease recurrence and adverse drug reactions of mycophenolate mofetil (MMF) in the treatment of childhood systemic lupus erythematosus (SLE). Methods The clinical data of SLE children who underwent MMF blood concentration test from January 2017 to June 2019 were retrospectively analyzed. The treatment regimens for the children in the last half year were hormone combined with MMF and hydroxychloroquine, and the dose of MMF was 20 - 40 mg/(kg·d). According to SLE disease activity score (SLEDAI), recurrence and adverse reactions and the levels of MPA AUC were compared among the groups. According to the level of MPA AUC, the patients were divided into three groups, and the disease activity and adverse reactions among the three groups were compared. Results A total of 81 ( 20 boys and 61 girls) children were enrolled and the median age was 13 . 1 ( 11 . 0 - 14 . 4 ) years. According to the 3 month-SLEDAI, 67 children were included in the inactive group and 14 were included in the active group. Compared with the inactive group, age at onset was younger, albumin and creatinine levels were lower and eGFR was higher in active group, and the differences were statistically significant (all P< 0 . 05 ). The MPA AUC0 - 12 h at 3 -month follow-up and 6 -month follow-up in the inactive group were higher than those in the active group, and the difference was statistically significant (P< 0 . 05 ). There were statistically significant differences in SLEDAI among the low, medium and high AUC groups at 3 month and 6 month follow-up, and the SLEDAI in low AUC group were the highest. The level of MPA AUC in the relapsed group was lower than that of the non-relapsed group, and the difference was statistically significant (P= 0. 001 ). The cut-off point of MPAAUC was 43. 03 mg /(h·L) when the ROC curve was used to predict the recurrence. The AUC was 0 . 89 (P= 0 . 001 ), the sensitivity was 100% and the specificity was 69 . 8%. Conclusions? It is important to monitor MPA AUC in the treatment of childhood SLE with MMF. There was a negative correlation between MPA AUC and disease activity. The serum concentration of mycophenolic acid higher than 43 . 03 mg/(hL) can maintain the low activity level of SLE and reduce disease recurrence, but excessive concentration does not improve disease activity.