Late prenatal dexamethasone and phenotype variations in 46,XX CAH: concerns about current protocols and benefits for surgical procedures

The management of congenital adrenal hyperplasia during preconception, pregnancy, and postpartum

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders of steroidogenesis of the adrenal cortex, most commonly due to 21-hydroxylase deficiency caused by mutations in the CYP21A2 gene. Although women with CAH have decreased fecundity, they are able to conceive; thus, if pregnancy is not desired, contraception options should be offered. If fertility is desired, women with classic CAH should first optimize glucocorticoid treatment, followed by ovulation induction medications and gonadotropins if needed. Due to the possible pregnancy complications and implications on the offspring, preconception genetic testing and counseling with a high-risk obstetrics specialist is recommended. For couples trying to avoid having a child with CAH, care with a reproductive endocrinology and infertility specialist to utilize in vitro fertilization can be offered, with or without preimplantation genetic testing for monogenic disorders. Prenatal screening and diagnosis options during pregnancy include maternal serum cell free-DNA for sex of the baby, and chorionic villus sampling and amniocentesis for diagnosis of CAH. Pregnant women with classic CAH need glucocorticoids to be adjusted during the pregnancy, at the time of delivery, and postpartum, and should be monitored for adrenal crisis. Maternal and fetal risks may include chorioamnionitis, maternal hypertension, gestational diabetes, cesarean section, and small for gestational age infants. This review on CAH due to 21-hydroxylase deficiency highlights reproductive health including genetic transmission, contraception options, glucocorticoid management, fertility treatments, as well as testing, antenatal monitoring, and management during pregnancy, delivery, and postpartum.

Prenatal dexamethasone treatment for classic 21-hydroxylase deficiency in Europe

OBJECTIVE

To assess the current medical practice in Europe regarding prenatal dexamethasone (Pdex) treatment of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency.

DESIGN AND METHODS

A questionnaire was designed and distributed, including 17 questions collecting quantitative and qualitative data. Thirty-six medical centres from 14 European countries responded and 30 out of 36 centres were reference centres of the European Reference Network on Rare Endocrine Conditions, EndoERN.

RESULTS

Pdex treatment is currently provided by 36% of the surveyed centres. The treatment is initiated by different specialties, that is paediatricians, endocrinologists, gynaecologists or geneticists. Regarding the starting point of Pdex, 23% stated to initiate therapy at 4-5 weeks postconception (wpc), 31% at 6 wpc and 46 % as early as pregnancy is confirmed and before 7 wpc at the latest. A dose of 20 µg/kg/day is used. Dose distribution among the centres varies from once to thrice daily. Prenatal diagnostics for treated cases are conducted in 72% of the responding centres. Cases treated per country and year vary between 0.5 and 8.25. Registries for long-term follow-up are only available at 46% of the centres that are using Pdex treatment. National registries are only available in Sweden and France.

CONCLUSIONS

This study reveals a high international variability and discrepancy in the use of Pdex treatment across Europe. It highlights the importance of a European cooperation initiative for a joint international prospective trial to establish evidence-based guidelines on prenatal diagnostics, treatment and follow-up of pregnancies at risk for CAH.

Congenital Adrenal Hyperplasia Due to Steroid 21-Hydroxylase Deficiency: An Endocrine Society Clinical Practice Guideline

Objective

To update the congenital adrenal hyperplasia due to steroid 21-hydroxylase deficiency clinical practice guideline published by the Endocrine Society in 2010.

Conclusions

The writing committee presents updated best practice guidelines for the clinical management of congenital adrenal hyperplasia based on published evidence and expert opinion with added considerations for patient safety, quality of life, cost, and utilization.

Nouveautés dans l’hyperplasie congénitale des surrénales

Congenital adrenal hyperplasia is an autosomal recessive disease due to functional abnormalities of adrenal steroid enzymes. The most common form of the disease is due to a 21-hydroxylase deficiency. The classical forms (most severe) are characterized by a deficiency in cortisol and sometimes in aldosterone, which may compromise the vital prognosis of neonates, and by an increase in androgen synthesis, leading to the virilization of girls' external genitalia at birth, followed by clinical signs of hyperandrogenism during childhood and adolescence. Neonatal screening has improved management and reduced morbidity and mortality in the neonatal period, but its performance could be broadly optimised by adjusting the assay techniques or the biomarkers used. The genetic diagnosis is difficult owing to the large genetic heterogeneity of the 6p21.3 region, which contains the CYP21A2 gene, especially with respect to the use of new-generation techniques of sequencing. Prenatal diagnosis is now possible as early as 6 weeks of gestation, but prenatal treatment remains controversial, awaiting results from prospective cohorts evaluating its long-term impact. Since conventional therapies have limitations, new therapies are currently being developed to allow better control of androgen synthesis and a substitutive treatment that respects the physiological rhythm of cortisol secretion, which would limit the development of long-term complications.

MANAGEMENT OF ENDOCRINE DISEASE: Congenital adrenal hyperplasia due to 21-hydroxylase deficiency: update on the management of adult patients and prenatal treatment

Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency is characterized by cortisol and in some cases aldosterone deficiency associated with androgen excess. Goals of treatment are to replace deficient hormones and control androgen excess, while avoiding the adverse effects of exogenous glucocorticoid. Over the last 5 years, cohorts of adults with CAH due to 21-hydroxylase deficiency from Europe and the United States have been described, allowing us to have a better knowledge of long-term complications of the disease and its treatment. Patients with CAH have increased mortality, morbidity and risk for infertility and metabolic disorders. These comorbidities are due in part to the drawbacks of the currently available glucocorticoid therapy. Consequently, novel therapies are being developed and studied in an attempt to improve patient outcomes. New management strategies in the care of pregnancies at risk for congenital adrenal hyperplasia using fetal sex determination and dexamethasone have also been described, but remain a subject of debate. We focused the present overview on the data published in the last 5 years, concentrating on studies dealing with cardiovascular risk, fertility, treatment and prenatal management in adults with classic CAH to provide the reader with an updated review on this rapidly evolving field of knowledge.

New developments in prenatal diagnosis of congenital adrenal hyperplasia

Congenital adrenal hyperplasia (CAH) owing to 21-hydroxylase deficiency is an autosomal recessive disorder caused by mutations in the CYP21A2 gene. Females affected with classical CAH are at risk for genital ambiguity, but can be treated in utero with dexamethasone before 9 gestational weeks to prevent virilization. Early genetic diagnosis is unavailable through current invasive methods of chorionic villus sampling and amniocentesis. New developments in prenatal genetic testing utilize fetal DNA extracted from maternal blood through noninvasive methods, which allow the determination of fetal gender and the diagnosis of CAH at an early gestational age (<9 weeks). Noninvasive prenatal diagnosis allows for the establishment of early and effective management plans in fetuses at risk for CAH and avoids unnecessary prenatal dexamethasone treatment.

Surgery in disorders of sex development (DSD) with a gender issue: If (why), when, and how?

Ten years after the consensus meeting on disorders of sex development (DSD), genital surgery continues to raise questions and criticisms concerning its indications, its technical aspects, timing and evaluation. This standpoint details each distinct situation and its possible management in 5 main groups of DSD patients with atypical genitalia: the 46,XX DSD group (congenital adrenal hyperplasia); the heterogeneous 46,XY DSD group (gonadal dysgenesis, disorders of steroidogenesis, target tissues impairments …); gonosomic mosaicisms (45,X/46,XY patients); ovo-testicular DSD; and "non-hormonal/non chromosomal" DSD. Questions are summarized for each DSD group with the support of literature and the feed-back of several world experts. Given the complexity and heterogeneity of presentation there is no consensus regarding the indications, the timing, the procedure nor the evaluation of outcome of DSD surgery. There are, however, some issues on which most experts would agree: 1) The need for identifying centres of expertise with a multidisciplinary approach; 2) A conservative management of the gonads in complete androgen insensitivity syndrome at least until puberty although some studies expressed concerns about the heightened tumour risk in this group; 3) To avoid vaginal dilatation in children after surgical reconstruction; 4) To keep asymptomatic mullerian remnants during childhood; 5) To remove confirmed streak gonads when Y material is present; 6) It is likely that 46,XY cloacal exstrophy, aphallia and severe micropenis would do best raised as male although this is based on limited outcome data. There is general acknowledgement among experts that timing, the choice of the individual and irreversibility of surgical procedures are sources of concerns. There is, however, little evidence provided regarding the impact of non-treated DSD during childhood for the individual development, the parents, society and the risk of stigmatization. The low level of evidence should lead to design collaborative prospective studies involving all parties and using consensual protocols of evaluation.

Preventing female virilisation in congenital adrenal hyperplasia: The controversial role of antenatal dexamethasone

Congenital adrenal hyperplasia (CAH) refers to a group of recessively inherited disorders of cortisol production, which in the classical form results in virilisation of female fetuses. Since the 1980s, antenatal treatment with dexamethasone has been recommended in high-risk pregnancies to minimise the risk of virilising the female genitalia of affected fetuses. To be effective, this treatment requires implementation in early pregnancy, prior to the commencement of autonomous fetal adrenal androgen synthesis. Using this approach, seven of eight high-risk pregnancies are treated unnecessarily, prior to establishing the fetal gender or the confirmed diagnosis of a genetically affected pregnancy. In the face of ongoing concerns regarding potential adverse maternal-fetal effects of antenatal dexamethasone exposure, a review of this practice has been advocated by expert advisory groups. In this review, we summarise current controversies, potential improvements and future directions in the management of pregnancies at risk of CAH. In high-risk families, recent genomic advances include early prenatal diagnosis utilising noninvasive genetic techniques to minimise unnecessary dexamethasone exposure to unaffected fetuses. In affected pregnancies when families elect for antenatal treatment, optimal antenatal dosing regimens need to be defined and a standardised treatment and follow-up protocol are recommended. Establishment of a national registry with standardised follow-up will allow future families to be better informed of the risks and benefits of both treated and untreated fetal CAH.