Incidence of Congenital Adrenal Hyperplasia in Great Britain
Should Newborns Be Screened for CAH?
Their research was published as the article “Incidence and clinical features of congenital adrenal hyperplasia in Great Britain” in the February 2012 issue of Archives of Disease in Childhood.
Researchers wanted to make an estimate of the incidence of clinically-diagnosed CAH; they also looked at clinical features and the age at first presentation. A third objective was to examine the benefit of screening all newborns for CAH.
The researchers used active surveillance through the British Paediatric Surveillance Unit. They included all children younger than 16 who were newly diagnosed with CAH, and the study was done prospectively between the dates noted above.
There were 12 labs which reported new CAH diagnoses between August 2007 and January 2009, and clinicians who diagnosed the patients filled out clinical questionnaires.
In the study, there were 144 children. Of those, 132 (92%) had 21-hydroxylase deficiency. It was noted that 36 (25%) were Asian; 62 (43%) were boys.
The incidence of new diagnoses in children younger than 16 was 0.60 (95% CI; 0.50 to 0.71) per 100,000.
Some children—86 (59%; 36 boys)—were diagnosed before they turned a year old: estimated birth prevalence of 5.48 (95% CI; 4.42 to 6.81) per 100,000. Of those 86, 77 of them presented with CAH within the first month of life.
Three-quarters of the girls evidenced virilized genitalia.
Salt-wasting crisis was seen in 27 newborns when they first presented; of those, 18 (67%; 16 boys) presented on or after 14 days of life.
The researchers concluded that approximately 1 in every 18,000 child in Great Britain is born with congenital adrenal hyperplasia.
Although similar numbers of girls and boys presented in the first year of life, it was seen that boys present more often with salt-wasting crisis or other severe manifestations. Researchers concluded that about 70% of newborns who present with salt-wasting crisis would be detected through newborn screening for CAH.