低剂量左甲状腺素治疗先天性甲状腺功能减低症的疗效观察

Curative Effect of Low Dose of Levothyroxine in Treatment of Congenital Hypothyroidism

目的 探讨不同剂量左甲状腺素治疗先天性甲状腺功能减低症（congenital hypothyroidism,CH）的临床疗效,以寻找最佳治疗剂量.方法 选择CH 60例,随机分为低剂量组和常规剂量组各30例,均应用左甲状腺素治疗.常规剂量组起始剂量10 ～ 15 μg/（kg·d）,维持剂量80 ～ 100 μg/d;低剂量组起始剂量8～10μg/（kg·d）,维持剂量50～ 80 μg/d.观察两组治疗2个月时甲状腺功能指标及治疗至2岁时智力情况.结果 治疗2个月时,两组FT3和FT4差异无统计学意义（P＞0.05）；低剂量组TSH值（2.6±1.2） mU/L明显低于常规剂量组（11.3±8.2） mU/L,差异有统计学意义（P＜0.01）.2岁时参照儿童韦氏智力测试量表（C-WYCSI）检测患儿操作智商（PIQ）、语言智商（VIQ）和总智商（FIQ）的变化情况,低剂量组各项指标均高于常规剂量组,差异有统计学意义（P＜0.01）.结论 应用低剂量左甲状腺素治疗CH有助于改善患儿的甲状腺功能和智力水平,推荐剂量为起始剂量8～10μg/（kg·d）,维持剂量50～ 80 μg/d.

Objective To investigate the clinical efficacy of different doses levothyroxine in treatment of congenital hypothyroidism （CH） to find the optimal therapeutic dosage. Methods A total of 60 patients with CH were randomly divided into low-dose group （n = 30） and routine dose group （n = 30） , and all patients received levothyroxine treatment. The routine dose group was treated with 10-15 μg/（ kg · d） of initial dose and 80-100 μg/d of maintenance dose; the low-dose group was treated with 8-10 μg/（kg · d） of starting dose and 50-80 μg/d of maintenance dose. The thyreoid functional parameters in two groups were observed after treatment for 2 months, and intelligence status was also observed in patients who received con- tinued treatment at the age of two. Results After treatment for 2 months, the differences of values of FT3 and FT4 in two groups were not statistically significant （ P 〉 0.05 ） ; TSH value of （2.6 ± 1.2） mU/L in low-dose group was significantly lower than that of （11.3 ±8.2） mU/L in routine dose group, and the differences were statistically significant （ P 〈0. 01 ）. The changes of performance intelligence quotient （PIQ） , verbal intelligence （VIQ） and full-scale intelligence quotient （FIQ） were detected by Wechsler intelligence scale （C-WYCSI） when patients were two years old. The indexes in low dose group were significantly higher than those in routine dosage group, and the differences were statistically significant （ P 〈 0.01 ）. Conclusion Low dose of levothyroxine in treatment of congenital hypothyroidism may improve thyroid function and intelli- gence level, and the recommended doses are 8-10 μg/d of initial dose and 50-80 μg/d of maintenance dose.