Lele, a 4.5-year-old boy, weighed 3.4 kg at birth and was 50 cm tall. He ate regularly, but his height grew significantly faster than children his age. The parents felt that their height was not high and it was good for the child to grow tall, but in the past two years it was found that the growth was also too fast, the 4-year-old child, as tall as the neighbor’s 7-year-old child, and a few days ago the childish voice also began to be hoarse, finally sinking to the hospital for examination. After a series of tests, the final diagnosis of congenital adrenocortical hyperplasia, bone age has reached 14 years old, the final height is seriously affected. The parents regretted not taking their child to the hospital for examination earlier. There are many similar examples. What exactly is this disease? Congenital adrenocortical hyperplasia is a group of diseases caused by congenital defects in one or several enzymes in the adrenocortical hormone biosynthesis enzyme system, resulting in altered levels of hormones such as cortisol. It is often inherited in an autosomal recessive manner. Clinical manifestations vary, with some children exhibiting significantly faster height growth than children of the same age, and eventually short stature. Early diagnosis and intervention are needed. At present, screening for neonatal diseases has been carried out in some areas. Blood can be collected from the heel of the newborn 3 to 5 days after birth, dropped on a special filter paper sheet, and the concentration of 17-OHP in the filter paper sheet can be measured by various testing methods, such as enzyme-linked immunosorbent assay (ELISA) and fluorescent immunoassay, for early diagnosis.