Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders affecting cortisol biosynthesis. Reduced activity of an enzyme required for cortisol production leads to chronic overstimulation of the adrenal cortex and accumulation of precursors proximal to the blocked enzymatic step. The most common form of CAH is caused by steroid 21- hydroxylase deficiency due to mutations in CYP21A2. Since the last publication summarizing CAH in Endocrine Reviews in 2000 there have been numerous new developments. These include more detailed understanding of steroidogenic pathways, refinements in neonatal screening, improved diagnostic measurements utilizing chromatography and mass spectrometry coupled with steroid profiling, and improved genotyping methods. Clinical trials of alternative medications and modes of delivery have been recently completed or are under way. Genetic and cell-based treatments are being explored. A large body of data concerning long-term outcomes in patients affected by CAH, including psychosexual well-being, has been enhanced by the establishment of disease registries. This review provides the reader with current insights in congenital adrenal hyperplasia with special attention to these new developments.

SummaryContext As a result of the introduction of treatment with glucocorticoids and mineralocorticoids, now 60 years ago, congenital adrenal hyperplasia has become a lifelong chronic disease. Whether long-term treatment of the disease leads to long-term side effects remains unknown. In this respect, especially cardiovascular risk seems to be important. Evidence synthesis We reviewed the reported prevalence of conventional cardiovascular risk factors, i.e. obesity, insulin resistance, high blood pressure and dyslipidaemia in patients with congenital adrenal hyperplasia. Overall, the studies suggest a tendency towards an increased body mass index and fat mass, the presence of insulin resistance and hypertension, although data are relatively scarce and obtained in heterogeneous populations. Conclusions Our findings suggest that adult CAH patients tend to have a cluster of metabolic risk factors, which are consistent with the metabolic syndrome. This notion may have consequences for the care for this group of patients.

There was no funding for this study. S.F., Y.H., K.D., W.L.M.N., D.S., H.L.C.-v.d.G. and L.R. declare to have no conflicts of interests. D.D.M.B. reports grants from Merck Serono, grants from Ferring and grants from MSD, outside the submitted work. K.F. reports personal fees from MSD (commercial sponsor), personal fees from Ferring (commercial sponsor), grants from Merck-Serono (commercial sponsor), grants from Ferring (commercial sponsor) and grants from MSD (commercial sponsor), outside the submitted work.

<b><i>Introduction:</i></b> Almost 20 years after the first international guidelines on the diagnosis and treatment of GHD have been published, clinical practice varies significantly. The low accuracy of endocrine tests for GHD and the burden caused by ineffective treatment of individual patients were strong motives for national endocrine societies to set up national guidelines regarding how to diagnose GHD in childhood. This audit aims to review the current state and identify common changes, which may improve the diagnostic procedure. <b><i>Methods:</i></b> A group of eight German pediatric endocrinologists contacted eight pediatric endocrinologists from Spain, France, Poland, the UK, the Netherlands, Denmark, Italy, and the US. Each colleague responded as a representative for the own country to a detailed questionnaire containing 22 open questions about national rules, guidelines, and practice with respect to GHD diagnostics and GH prescription. The results were presented and discussed in a workshop and then documented in this study which was reviewed by all participants. <b><i>Results:</i></b> National guidelines are available in 7 of 9 countries. GH is prescribed by pediatric endocrinologists in most countries. Some countries have established boards that review and monitor prescriptions. Preferred GH stimulation tests and chosen cutoffs vary substantially. Overall, a trend to lowering the GH cutoff was identified. Priming is becoming more popular and now recommended in 5 out of 9 countries; however, with different protocols. The definition of pretest-conditions that qualify the patient to undergo GH testing varies substantially in content and strictness. The most frequently used clinical sign is low height velocity, but definition varies. Height, IGF-1, and bone age are additional parameters recommended in some countries. <b><i>Conclusions:</i></b> GHD diagnostics varies substantially in eight European countries and in the US. It seems appropriate to undertake further efforts to harmonize endocrine diagnostics in Europe and the US based on available scientific evidence.