ABSTRACT
Objective To investigate the distribution of human thyroid stimulation hormone(hTSH) in dried venous blood spots of neonatal screening for congenital hypothyroidism in Guilin ,and establish the hTSH cut‐off value for neonatal screening .Methods We selected 101 817 cases of neonatals with the local household registration from January 2011 to December 2013 ,and collected their venous blood to be made into dried venous blood spots on filter paper ,then the hTSH levels in dried blood spots were deter‐mined for congenital hypothyroidism ,According to screening results ,using the percentile method to calculate the hTSH P50 ,P99 of all the normal neonatals and neonatals that born in different quarters .Results Among 101 817 neonatals who were screened ,101 746 cases of normal neonatals ,71 cases of patients(including 47 cases of patients with CH ,24 cases of patients with high hTSH hy‐perlipidemia) ,the hTSH levels of normal neonatals showing a skewed distribution ,P50 ,P99 were 2 .45 μU/mL ,9 .86 μU/mL .the hTSH levels of the neonatal who were born in different quarters was changed with the change in the quarter ,P50 ,P99 were 2 .15μU/mL ,9 .20 μU/mL in The Spring ;P50 ,P99 were 1 .97 μU/mL ,8 .38 μU/mL in the summer ;P50 ,P99 were 2 .67 μU/mL ,10 .43μU/mL in the autumn ;P50 ,P99 were 2 .90μU/mL ,11 .15μU/mL in the winter .Through the analysis ,although the hTSH cut‐off of capillary blood spots that was used in the local center could be applied to dried venous blood spots ,but not ideal cut‐off value .Even‐tually ,the hTSH P99 9 .20μU /mL in the spring was identified as cut‐off value of dried venous blood spots for routine screening la‐boratory ,which had a sensitivity of 100 .00% ,a specificity of 36 .80% ,the diagnosis rate of 38 .96% ,and no missed phenomena .For the better service ,the hTSH value in the range of 9 .20-20 .00 μU/mL was defined as the boundary region ,and it was the danger region when the hTSH value was higher than 20 .00 μU/mL .Conclusion It is necessary to establish a reasonable hTSH cut‐off value to provide objective evidence for the use of dried venous blood spots of neonatal screening for congenital hypothyroidism ,ac‐cording to the boundary region and the danger region ,the recall chosen a different way ,the development of neonatal screening can be effectively promoted .