Hospital Infantil Joana de Gusmão, Departamento de Endocrinologia Pediátrica, Florianópolis, SC, Brasil,
Universidade Federal de Santa Catarina (UFSC), Florianópolis, SC, Brasil.
Arch Endocrinol Metab. 2021 Nov 1;64(6):816-823. doi: 10.20945/2359-3997000000299. Epub 2020 Oct 21.
To assess the implications of changing the cutoff level of TSH from 10 to 6 mIU/L.
The study population was constituted by 74.123 children screened for congenital hypothyroidism by the National Screening Program in Santa Catarina, from March 2011 to February 2012. The cutoff of TSH was 6 mIU/L. If TSH between 6-10 mIU/L, the newborn was recalled for a second TSH measurement on filter paper. If TSH > 6 mIU/L in the second sample, the child was sent for medical evaluation. In children with normal topic thyroid, levothyroxine was suspended for 1 month at the age of 3 years for identification of the etiology and evaluation of the need to continue treatment.
Among the children screened, 435 were recalled for presenting TSH between 6 and 10 mIU/L in the first sample, 28 remained TSH > 6 mIU/L in the second sample. Among these, 11 had a final diagnosis of dyshormonogenesis, two of ectopic thyroid, two of thyroid hypoplasia and one of transient hypothyroidism. Ten children presented normal TSH levels on the first medical evaluation and two lost follow-up.
A decrease in the TSH cutoff level from 10 to 6 mIU/L in a neonatal screening program for congenital hypothyroidism reduced the number of false-negative results, increasing the sensitivity of the test, but increased the number of false-positive results and recalls. Since a TSH cutoff level of 6 mIU/L detects thyroid function abnormalities requiring treatment, the adoption of this cutoff level is justified.
评估将 TSH 截断值从 10 mIU/L 更改为 6 mIU/L 的影响。
该研究人群由 2011 年 3 月至 2012 年 2 月期间通过圣卡塔琳娜州国家筛查计划筛查先天性甲状腺功能减退症的 74123 名儿童组成。TSH 的截断值为 6 mIU/L。如果 TSH 在 6-10 mIU/L 之间，新生儿将被召回进行第二次滤纸 TSH 测量。如果第二次样本中 TSH>6 mIU/L，则将儿童转至医疗评估。对于甲状腺功能正常的儿童，在 3 岁时暂停左旋甲状腺素治疗 1 个月，以确定病因并评估是否需要继续治疗。
在所筛查的儿童中，有 435 名因初次样本 TSH 处于 6-10 mIU/L 之间而被召回，其中 28 名儿童在第二次样本中 TSH>6 mIU/L。其中，有 11 名儿童最终诊断为甲状腺激素合成障碍，2 名儿童为异位甲状腺，2 名儿童为甲状腺发育不全，1 名儿童为短暂性甲状腺功能减退。在第一次医学评估中，有 10 名儿童 TSH 水平正常，2 名儿童失访。
新生儿先天性甲状腺功能减退症筛查的 TSH 截断值从 10 mIU/L 降低至 6 mIU/L 减少了假阴性结果的数量，提高了检测的敏感性，但增加了假阳性结果和召回的数量。由于 TSH 截断值为 6 mIU/L 可以检测到需要治疗的甲状腺功能异常，因此采用该截断值是合理的。
