ESPEYB18 13. Global Health for the Paediatric Endocrinologist Endocrinology (11 abstracts)
Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Department of Endocrinology, Shenzhen Childrens Hospital, Shenzhen, China. liangyan@tjh.tjmu.edu.cn.
Front Endocrinol 2021; 12:624507. doi: 10.3389/fendo.2021.624507
This systematic review identified 41 Chinese studies totalling 7,853,756 newborns who underwent neonatal CAH screening The overall incidence of CAH in China was 1/23,024 (95% CI, 1/25,757 to 1/20,815) Among the CAH patients, the Male:Female ratio was 1.92:1, and 76% presented with salt wasting
The number of neonates screened is impressive (>7.8 million). This large number of tests provides a precise overall incidence for CAH in China of 1:23 024, lower than in Caucasian populations, and than in populations with high rates of consanguinity (CAH incidence was reported to be 1:7908 in Saudi Arabia and 1:9030 in the United Arab Emirates). However, this incidence should be interpreted in the light of the fact that the programs covered only < 20% of the population, that richer regions are overrepresented and that there are large variations from region to region and several relatively small size programs (22% of programs screened < 50 000 neonates).
The most surprising finding was a Male:Female ratio close to 2 for CAH. Such a difference has not been reported elsewhere and, as mentioned by the authors, is not easy to understand, considering that CAH is an autosomal recessive condition (a ratio close to 1 would be expected). Several points, not mutually exclusive, may explain this finding. First, the overall Male:Female sex ratio at birth is 1.1 in China. Second, it is possible that girls are diagnosed clinically early (due to virilization) and therefore do not undergo screening. Third, Chinese parents may pay more attention to boys, such that the recall rate of positive boys may be higher than that of girls. Finally, the authors highlight a study in the USA that found a higher sensitivity of the screening for boys than for girls.