Cognitive and social function in girls with congenital adrenal hyperplasia — Influence of prenatally administered dexamethasone

Prenatal and Pregnancy Management of Congenital Adrenal Hyperplasia

Management of patients with congenital adrenal hyperplasia (CAH) poses challenges during pregnancy and prenatal stages, impacting fertility differently in men and women. Women with CAH experience menstrual irregularities due to androgen and glucocorticoid precursor interference with endometrial development and ovulation. Genital surgeries for virilization and urogenital anomalies further impact fertility and sexual function, leading to reduced heterosexual relationships among affected women. Fertility rates vary, with a lower prevalence of motherhood, primarily among those with classic CAH, necessitating optimized hormonal therapy for conception. Monitoring optimal disease control during pregnancy poses challenges due to hormonal fluctuations. Men with CAH often experience hypogonadotrophic hypogonadism and complications like testicular adrenal rest tissue, impacting fertility. Regular monitoring and intensified glucocorticoid therapy may restore spermatogenesis. Genetic counselling is vital to comprehend transmission risks and prenatal implications. Prenatal dexamethasone treatment in affected female fetuses prevents virilization but raises ethical and safety concerns, necessitating careful consideration and further research. The international "PREDICT" study aims to establish safer and more effective prenatal therapy in CAH, evaluating dosage, safety, and long-term effects.

Dexamethasone induces developmental axon damage in the offspring hippocampus by activating miR-210-3p/miR-362-5p to target the aberrant expression of Sonic Hedgehog

Given the extensive application of dexamethasone in both clinical settings and the livestock industry, human exposure to this drug can occur through various sources and pathways. Prior research has indicated that prenatal exposure to dexamethasone (PDE) heightens the risk of cognitive and emotional disorders in offspring. Axonal development impairment is a frequent pathological underpinning for neuronal dysfunction in these disorders, yet it remains unclear if it plays a role in the neural damage induced by PDE in the offspring. Through RNA-seq and bioinformatics analysis, we found that various signaling pathways related to nervous system development, including axonal development, were altered in the hippocampus of PDE offspring. Among them, the Sonic Hedgehog (SHH) signaling pathway was the most significantly altered and crucial for axonal development. By using miRNA-seq and targeting miRNAs and glucocorticoid receptor (GR) expression, we identified miR-210-3p and miR-362-5p, which can target and suppress SHH expression. Their abnormal high expression was associated with GR activation in PDE fetal rats. Further testing of PDE offspring rats and infant peripheral blood samples exposed to dexamethasone in utero showed that SHH expression was significantly decreased in peripheral blood mononuclear cells (PBMCs) and was positively correlated with SHH expression in the hippocampus and the expression of the axonal development marker growth-associated protein-43. In summary, PDE-induced hippocampal GR-miR-210-3p/miR-362-5p-SHH signaling axis changes lead to axonal developmental damage. SHH expression in PBMCs may reflect axonal developmental damage in PDE offspring and could serve as a warning marker for fetal axonal developmental damage.

Safety of Antenatal Predniso(lo)ne and Dexamethasone on Fetal, Neonatal and Childhood Outcomes: A Systematic Review

CONTEXT

Due to ethical considerations, antenatal dose finding for prednisolone and dexamethasone in pregnant women is limited, leading to a knowledge gap.

OBJECTIVE

In order to guide the clinician in weighing benefits vs risks, the aim is to systematically review the current literature on the side effects of antenatal predniso(lo)ne and dexamethasone use on the fetus, newborn, and (pre)pubertal child.

EVIDENCE ACQUISITION

The search was performed in PubMed/MEDLINE and Embase using prespecified keywords and Medical Subject Headings. This systematic review investigated studies published until August 2022, with the following inclusion criteria: studies were conducted in humans and assessed side effects of long-term antenatal predniso(lo)ne and dexamethasone use during at least one of the trimesters on the child during the fetal period, neonatal phase, and during childhood.

EVIDENCE SYNTHESIS

In total, 328 papers in PubMed and 193 in Embase were identified. Fifteen studies were eligible for inclusion. Seven records were added through references. Antenatal predniso(lo)ne use may be associated with lower gestational age, but was not associated with miscarriages and stillbirths, congenital abnormalities, differences in blood pressure or low blood glucose levels at birth, or with low bone mass, long-term elevated cortisol and cortisone, or high blood pressure at prepubertal age. Increased risks of antenatal dexamethasone use include association with miscarriages and stillbirths, and from age 16 years, associations with disturbed insulin secretion and higher glucose and cholesterol levels.

CONCLUSIONS

Based on the limited evidence found, predniso(lo)ne may have less side effects compared with dexamethasone in short- and long-term outcomes. Current literature shows minimal risk of side effects in the newborn from administration of a prenatal predniso(lo)ne dose of up to 10 mg per day.

Gestational dexamethasone exposure impacts hippocampal excitatory synaptic transmission and learning and memory function with transgenerational effects

The formation of learning and memory is regulated by synaptic plasticity in hippocampal neurons. Here we explored how gestational exposure to dexamethasone, a synthetic glucocorticoid commonly used in clinical practice, has lasting effects on offspring's learning and memory. Adult offspring rats of prenatal dexamethasone exposure (PDE) displayed significant impairments in novelty recognition and spatial learning memory, with some phenotypes maintained transgenerationally. PDE impaired synaptic transmission of hippocampal excitatory neurons in offspring of F1 to F3 generations, and abnormalities of neurotransmitters and receptors would impair synaptic plasticity and lead to impaired learning and memory, but these changes failed to carry over to offspring of F5 and F7 generations. Mechanistically, altered hippocampal miR-133a-3p-SIRT1-CDK5-NR2B signaling axis in PDE multigeneration caused inhibition of excitatory synaptic transmission, which might be related to oocyte-specific high expression and transmission of miR-133a-3p. Together, PDE affects hippocampal excitatory synaptic transmission, with lasting consequences across generations, and CDK5 in offspring's peripheral blood might be used as an early-warning marker for fetal-originated learning and memory impairment.

Congenital adrenal hyperplasia

Congenital adrenal hyperplasia is a group of autosomal recessive disorders leading to multiple complex hormonal imbalances caused by various enzyme deficiencies in the adrenal steroidogenic pathway. The most common type of congenital adrenal hyperplasia is due to steroid 21-hydroxylase (21-OHase, henceforth 21OH) deficiency. The rare, classic (severe) form caused by 21OH deficiency is characterised by life-threatening adrenal crises and is the most common cause of atypical genitalia in neonates with 46,XX karyotype. After the introduction of life-saving hormone replacement therapy in the 1950s and neonatal screening programmes in many countries, nowadays neonatal survival rates in patients with congenital adrenal hyperplasia are high. However, disease-related mortality is increased and therapeutic management remains challenging, with multiple long-term complications related to treatment and disease affecting growth and development, metabolic and cardiovascular health, and fertility. Non-classic (mild) forms of congenital adrenal hyperplasia caused by 21OH deficiency are more common than the classic ones; they are detected clinically and primarily identified in female patients with hirsutism or impaired fertility. Novel treatment approaches are emerging with the aim of mimicking physiological circadian cortisol rhythm or to reduce adrenal hyperandrogenism independent of the suppressive effect of glucocorticoids.

Pregnancy and Prenatal Management of Congenital Adrenal Hyperplasia

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive diseases that may cause cortisol insufficiency together with other hormonal alterations. The most common form is 21-hydroxylase deficiency, in which the lack of pituitary negative feedback causes an increase in ACTH and adrenal androgens. Classical forms of CAHs can lead to severe adrenal failure and female virilization. To date, the appropriate management of pregnant CAH patients is still debated regarding appropriate maternal therapy modifications during pregnancy and the risks and benefits of prenatal treatment of the fetus. We conducted a literature search of relevant papers to collect current evidence and experiences on the topic. The most recent and significant articles were selected, and current international guidelines were consulted to update current recommendations and guide clinical practice. Given the lack of randomized clinical trials and other high-quality scientific evidence, the issue is still debated, and great heterogeneity exists in current practice in terms of risk/benefit evaluation and pharmacological choices for pregnancy and prenatal treatment. Glucocorticoid therapy is advised not only in classical CAH patients but also in non-classical, milder forms. The choice of which glucocorticoid to use, and the safety and benefits of dexamethasone therapy aimed at preventing genital virilization are still debated issues. Several advances, however, have been made, especially in terms of fertility and reproduction. This review aims to present the most recent scientific and real-world updates on pregnancy and prenatal management of CAH, with the presentation of various clinical scenarios and specific case-by-case recommendations.

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-Current Insights in Pathophysiology, Diagnostics, and Management

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 CAH with special attention to these new developments.

Behavioral Health Diagnoses in Youth with Differences of Sex Development or Congenital Adrenal Hyperplasia Compared with Controls: A PEDSnet Study

OBJECTIVE

To evaluate the odds of a behavioral health diagnosis among youth with differences of sex development (DSD) or congenital adrenal hyperplasia (CAH) compared with matched controls in the PEDSnet database.

STUDY DESIGN

All youth with a diagnosis of DSD (n = 1216) or CAH (n = 1647) and at least 1 outpatient encounter were extracted from the PEDSnet database and propensity-score matched on 8 variables (1:4) with controls (n = 4864 and 6588, respectively) using multivariable logistic regression. The likelihood of having behavioral health diagnoses was examined using generalized estimating equations.

RESULTS

Youth with DSD had higher odds of a behavioral health diagnosis (OR, 1.7; 95% CI, 1.4-2.1; P < .0001) and neurodevelopmental diagnosis (OR, 1.7; 95% CI, 1.4, 2.0; P < .0001) compared with matched controls. Youth with CAH did not have an increased odds of a behavioral health diagnosis (OR, 1.0; 95% CI, 0.9, 1.1; P = .9) compared with matched controls but did have higher odds of developmental delay (OR, 1.8; 95% CI, 1.4, 2.4; P < .0001).

CONCLUSIONS

Youth with DSD diagnosis have higher odds of a behavioral health or neurodevelopmental diagnosis compared with matched controls. Youth with CAH have higher odds of developmental delay, highlighting the need for screening in both groups.

Gender roles and behavioral problems in children with 21-hydroxylase deficiency in Southern China

PURPOSE

To assess the gender roles and behavioral outcomes in children with 21-hydroxylase deficiency (21-OHD) in Southern China.

METHODS

A total of 50 individuals with 21-OHD participated in our study, (30 boys and 20 girls), as well as another 19 age-matched non-affected relatives of patients (12 boys and 7 girls). Psychological adjustment was assessed with a preschool activity survey and a Conner parent symptom questionnaire was modified for retrospective reporting.

RESULTS

The response rate of the questionnaire in the control group was only 36.5%. All the patients were diagnosed with salt-wasting of 21-OHD. Our study revealed that the masculine score was higher in male patients with 21-OHD than male controls and female patients. Compared with that in the female 21-OHD patient group, the masculine score in the female control group was lower, while comparative masculinization was found in the male controls. Regarding behavioral problems, there was a higher incidence of parent-reported problems among children with 21-OHD than controls, including conduct problems, impulsive hyperactivity, anxiety, and hyperactivity index.

CONCLUSION

Parents of 21-OHD patients in Southern China were unwilling to disclose the condition of their children to the society. Masculinization and behavioral problems were prevalent among patients with 21-OHD, which highlighted the importance of psychological and social support for 21-OHD patients and their families.

Antenatal Corticosteroid Therapy Attenuates Angiogenesis Through Inhibiting Osteoclastogenesis in Young Mice

Antenatal corticosteroid therapy (ACT) has been shown to reduce morbidity and mortality rates in preterm delivery, but the fetus is more likely to face the risk of low bone mineralization and low fetal linear growth. However, the mechanism of ACT inducing low bone mineralization remains largely unknown. Pre-osteoclasts, which play an important role in angiogenesis and osteogenesis, are specifically regulating type H vessels (CD31^hiEmcn^hi) and vessel formation by secreting platelet-derived growth factor-BB (PDGF-BB). We find that the number of pre-osteoclasts and POC-secreted PDGF-BB is dramatically decreased in ACT mice, contributing to the reduction in type H vessels and bone mineralization during the mouse offspring. Quantitative analyses of micro-computed tomography show that the ACT mice have a significant reduction in the mass of trabecular bone relative to the control group. Mononuclear pre-osteoclasts in trabecular bone decreased in ACT mice, which leads to the amount of PDGF-BB reduced and attenuates type H vessel formation. After sorting the Rank+ osteoclast precursors using flow cytometry, we show that the enhancer of zeste homolog 2 (Ezh2) expression is decreased in Rank+ osteoclast precursors in ACT mice. Consistent with the flow data, by using small molecule Ezh2 inhibitor GSK126, we prove that Ezh2 is required for osteoclast differentiation. Downregulating the expression of Ezh2 in osteoclast precursors would reduce PDGF-BB production. Conditioned medium from osteoclast precursor cultures treated with GSK126 inhibited endothelial tube formation, whereas conditioned medium from vehicle group stimulated endothelial tube formation. These results indicate Ezh2 expression of osteoclast precursors is suppressed after ACT, which reduced the pre-osteoclast number and PDGF-BB secretion, thus inhibiting type H vessel formation and ACT-associated low bone mineralization.

Efficacy and safety of prenatal dexamethasone treatment in offspring at risk for congenital adrenal hyperplasia due to 21-hydroxylase deficiency: A systematic review and meta-analysis

OBJECTIVE

To assess the efficacy and safety of prenatal dexamethasone treatment in offspring at risk for congenital adrenal hyperplasia.

METHODS

MEDLINE, EMBASE, the Cochrane Library, the clinicaltrials.gov website databases were systematically searched from inception through March 2019. WMD and SMD with 95%CIs were calculated using random or fixed effects models.

RESULTS

There was a significant reduction in virilization in the DEX-treated group (WMD: -2.39, 95%CI: -3.31,-1.47). No significant differences were found in newborn physical outcomes for birth weight (WMD: 0.09, 95%CI: -0.09, 0.27) and birth length (WMD = 0.27, 95%CI: -0.68, 1.21). Concerning cognitive functions, no significant differences in the domains of psychometric intelligence (SMD: 0.05, 95%CI: -0.74, 0.83), verbal memory (SMD: -0.17, 95%CI: -0.58, 0.23), visual memory (SMD: 0.10, 95%CI: -0.14, 0.34), learning (SMD: -0.02, 95%CI: -0.27, 0.22) and verbal processing (SMD: -0.38, 95%CI: -0.93, 0.17). Regarding behavioural problems, no significant differences in the domains of internalizing problems (SMD: 0.16, 95%CI: -0.49, 0.81), externalizing problems (SMD: 0.07, 95%CI: -0.30, 0.43) and total problems (SMD: 0.14, 95%CI: -0.23, 0.51). With respect to temperament, no significant differences in the domains of emotionality (SMD: 0.13, 95%CI: -0.79, 1.05), activity (SMD: 0.04, 95%CI: -0.32, 0.39), shyness (SMD: 0.25, 95%CI: -0.70, 1.20) and sociability (SMD: -0.23, 95%CI: -0.90, 0.44).

CONCLUSIONS

Prenatal DEX treatment reduced virilization with no significant differences in newborn physical outcomes, cognitive functions, behavioural problems and temperament. The results need to be interpreted cautiously due to the existence of limitations.

Effectiveness of Prenatal Intervention on the Outcome of Diseases That Have a Postnatal Urological Impact

We reviewed the literature addressing outcomes of fetal intervention of conditions that require post-natal urological management including lower urinary tract obstruction, hydrometrocolpos, congenital adrenal hyperplasia, and myelomeningocele. Despite several decades of fetal intervention for these conditions, benefits remain elusive in part because of the enormous difficulty of conducting prospective randomized studies. In this review, we reached the following conclusions: Prenatal intervention in lower urinary tract obstruction (LUTO) improves survival in the worst cases by improving pulmonary function and it may be advantageous for renal function, particularly in patients with adverse urine parameters.Prenatal treatment of female fetuses at risk of having congenital adrenal hyperplasia (CAH) reduces virilization. Non-invasive fetal DNA analysis allows earlier diagnosis, reducing the risk of treating with dexamethasone males and non-affected fetuses.Fetal treatment of myelomeningocele (MMC) is gaining momentum. Prospective studies including standardized urologic evaluation will determine if the encouraging results reported by some hold on the long term follow-up.

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.

Prenatal Treatment of Congenital Adrenal Hyperplasia: Long-Term Effects of Excess Glucocorticoid Exposure

Prenatal treatment of congenital adrenal hyperplasia with dexamethasone (DEX) has been in use since the mid-1980s and has proven effective at reducing virilization of external genitalia in affected girls. However, multiple experimental studies on animals and clinical studies on humans show that prenatal administration of glucocorticoids may cause unwanted adverse effects which have raised concerns about the long-term safety of the treatment. The long-term outcome of prenatal DEX treatment on cognition has been investigated, but the results are still conflicting. Overall, most of the evidence points towards a negative effect on executive functions where girls seem to be more susceptible than boys. Some effects on social behavior have been observed, but results are still contradictory and treated children are mostly well adapted. Cardiovascular, renal, and metabolic function are still areas to be investigated. Larger studies are warranted to investigate areas other than cognition and behavior and to be able to draw more definitive conclusions about prenatal DEX treatment.

Course-, dose-, and stage-dependent toxic effects of prenatal dexamethasone exposure on long bone development in fetal mice

Dexamethasone is routinely used for treating those mothers at risk for preterm delivery. However, overexposure to exogenous glucocorticoids induces bone loss in offspring, and the "critical window" and safe dose of this treatment are largely unknown. In this study, we found that femoral length, and the length of the primary ossification center were significantly reduced in fetal mice after repeated prenatal dexamethasone exposure (PDE). Compared with single-course exposure on gestational day (GD)15, newborn mice with repeated PDE (3 times, from GD15 to 17) showed a significant decrease in femoral trabecular bone mass with decreased trabecular number and thickness. For those newborn mice treated after repeated PDE at different doses (0, 0.2, 0.8, and 1.2 mg/kg/d), the toxic effect of dexamethasone on bone development was observed at 0.8 and 1.2 mg/kg/d. More severe retardation in bone development was observed in the fetal mice after PDE at 0.8 mg/kg/d during GD12-14, compared with that during GD15-17. Interestingly, stronger toxic effects were observed in male newborn mice after PDE than were observed in female newborn mice. In conclusion, PDE with multiple course, higher dose, or exposure at an early stage of pregnancy have stronger toxic effects on bone development of fetal mice.

Prenatal dexamethasone treatment in the context of at risk CAH pregnancies: Long-term behavioral and cognitive outcome

Dexamethasone (DEX) is used to prevent prenatal virilization in female fetuses with congenital adrenal hyperplasia (CAH). Since treatment has to be started before the genotype of the fetus is known, 7 out of 8 fetuses will be exposed to DEX without benefit. Previously, we have observed negative effects on cognition and behavior in DEX treated children. Here we evaluated neuropsychological functions, psychopathology and autistic traits in non-CAH DEX-treated adults exposed during the first trimester of fetal life (duration 6.2 ± 2.2 weeks). Cognitive functions, psychopathology and autistic traits were compared between DEX-treated subjects (n = 23) and non-exposed controls (n = 58). Cognitive outcome was also evaluated longitudinally for DEX-treated participants. We used neuropsychological tests (Wechsler Scales and the Stroop Interference Test) and questionnaires assessing executive functions (the Barkley Deficit in Executive Functioning Scale), psychopathology (the Montgomery Åsberg Depression Ratings Scale, the Hospital Anxiety and Depression Scale, the Liebowitz Social Anxiety Scale) and autistic traits (Autism Quota). We did not observe any significant differences in cognition, psychopathology or autistic traits between DEX-treated individuals and population controls. A significant improvement in verbal working memory (p = 0.038) and in impulse inhibition (p = 0.011) was seen when subjects were evaluated longitudinally. In summary, first-trimester DEX-exposed adult individuals do not show any significant neuropsychological deficits nor an increase in anxiety, depression or autistic traits, compared with a control group from the general population. The results also suggest that the observed deficits in executive functioning during childhood may improve with time.

Management of Childhood Congenital Adrenal Hyperplasia-An Integrative Review of the Literature

Congenital adrenal hyperplasia (CAH) is an endocrine condition that requires parents to administer steroids up to three times daily, supplementing maintenance doses with oral or injectable doses during times of illness. The purpose of this integrative review was to explore the management, care, and associated health issues for children with CAH and the family response to the condition. Four literature indexes were searched, with 39 articles included. Four themes emerged: (a) Health- and Development-Related Issues, (a) Effects of Excess Androgens, (c) Life Experience of CAH, and (d) Managing and Averting Adrenal Crisis. Families having a child with CAH face complex concerns related their child's growth, the fear of adrenal crisis events, and the consequences of atypical genitalia for affected girls. Future studies should focus on interventions that provide guidelines to increase parental preparedness in managing adrenal crises and creating support systems for affected girls.

Mechanisms of Glucocorticoid Action During Development

Glucocorticoids are primary stress hormones produced by the adrenal cortex. The concentration of serum glucocorticoids in the fetus is low throughout most of gestation but surge in the weeks prior to birth. While their most well-known function is to stimulate differentiation and functional development of the lungs, glucocorticoids also play crucial roles in the development of several other organ systems. Mothers at risk of preterm delivery are administered glucocorticoids to accelerate fetal lung development and prevent respiratory distress. Conversely, excessive glucocorticoid signaling is detrimental for fetal development; slowing fetal and placental growth and programming the individual for disease later in adult life. This review explores the mechanisms that control glucocorticoid signaling during pregnancy and provides an overview of the impact of glucocorticoid signaling on fetal development.

Steroid 21-hydroxylase deficiency in congenital adrenal hyperplasia

Congenital adrenal hyperplasia (CAH) refers to a group of inherited genetic disorders involving deficiencies in enzymes that convert cholesterol to cortisol within the adrenal cortex. There are five key enzymes involved in the production of cortisol. Of these key enzymes, deficiency of 21-hydroxylase is the most commonly defective enzyme leading to CAH representing more than 90% of cases. The low adrenal cortisol levels associated with CAH affects the hypothalamic-pituitary-adrenal negative feedback system leading to increased pituitary adrenocorticotropic hormone (ACTH) production, which overstimulates the adrenal cortex in an attempt to increase cortisol production resulting in a hyperplastic adrenal cortex. The deficiency of enzyme 21-hydroxylase results from mutations or deletions in the CYP21A2 gene found on chromosome 6p. The disorder is transmitted as an autosomal recessive pattern and specific mutations may be correlated to enzymatic compromise of varying degrees, leading to the clinical manifestation of 21-hydroxylase deficiency (21-OHD) CAH.

Sex-Dimorphic Effects of Prenatal Treatment With Dexamethasone

CONTEXT

Dexamethasone (DEX) is used to prevent virilization in female fetuses at risk of congenital adrenal hyperplasia (CAH). Given that treatment has to be started before the genotype is known, 7 out of 8 fetuses will be exposed to DEX without benefit.

OBJECTIVE

To evaluate long-term cognitive effects of prenatal DEX therapy in healthy (non-CAH) DEX-treated children.

DESIGN AND SETTING

Observational study with patient and control groups from a single research institute.

PARTICIPANTS

Healthy (non-CAH) DEX-treated subjects (n = 34) and untreated population controls (n = 66) from Sweden, aged 7-17 years.

INTERVENTION

DEX-treatment used in unborn children at risk of CAH, during first trimester of fetal life.

MAIN OUTCOME MEASURES

Standardized neuropsychological tests and questionnaires were used.

RESULTS

DEX treatment has widespread negative effects in girls. In Wechsler Intelligence Scales for Children-III scale subtests, we observed significant interactions between DEX and GENDER (coding, P = .044; block design, P = .013; vocabulary, P = .025) and a trend for the subtest digit span (P = .074). All interactions were driven by DEX effects in girls, but not boys, with DEX-treated females showing lower scores than female untreated controls (coding, P = .068, d = 0.66; block design, P = .021, d = 0.81; vocabulary, P = .014, d = 0.84; digit span, P = .001, d = 1.0). Likewise, DEX-treated girls tend to have poorer visual spatial working memory performance than controls (span board test forward: P = .065, d = .80). We observed no effects on long-term memory, handedness, speed of processing, nor self-perceived or parentally reported scholastic performance.

CONCLUSIONS

Early prenatal DEX exposure affects cognitive functions in healthy girls, ie, children who do not benefit from the treatment. It can therefore not be considered safe to use this therapy in the context of CAH.

Mitogen-inducible gene-6 partly mediates the inhibitory effects of prenatal dexamethasone exposure on endochondral ossification in long bones of fetal rats

BACKGROUND AND PURPOSE

Prenatal exposure to dexamethasone slows down fetal linear growth and bone mineralization but the regulatory mechanism remains unknown. Here we assessed how dexamethasone regulates bone development in the fetus.

EXPERIMENTAL APPROACH

Dexamethasone (1 mg·kg(-1) ·day(-1) ) was injected subcutaneously every morning in pregnant rats from gestational day (GD)9 to GD20. Fetal femurs and tibias were harvested at GD20 for histological and gene expression analysis. Femurs of 12-week-old female offspring were harvested for microCT (μCT) measurement. Primary chondrocytes were treated with dexamethasone (10, 50, 250 and 1000 nM).

KEY RESULTS

Prenatal dexamethasone exposure resulted in accumulation of hypertrophic chondrocytes and delayed formation of the primary ossification centre in fetal long bone. The retardation was accompanied by reduced maturation of hypertrophic chondrocytes, decreased osteoclast number and down-regulated expression of osteocalcin and bone sialoprotein in long bone. In addition, the mitogen-inducible gene-6 (Mig6) and osteoprotegerin (OPG) expression were stimulated, and the receptor activator of NF-κB ligand (RANKL) expression was repressed. Moreover, dexamethasone activated OPG and repressed RANKL expression in both primary chondrocytes and primary osteoblasts, and the knockdown of Mig6 abolished the effect of dexamethasone on OPG expression. Further, μCT measurement showed loss of bone mass in femur of 12-week-old offspring with prenatal dexamethasone exposure.

CONCLUSIONS AND IMPLICATIONS

Prenatal dexamethasone exposure delays endochondral ossification by suppressing chondrocyte maturation and osteoclast differentiation, which may be partly mediated by Mig6 activation in bone. Bone development retardation in the fetus may be associated with reduced bone mass in later life.

Prenatal Diagnosis of Congenital Adrenal Hyperplasia

Congenital adrenal hyperplasia (CAH) owing to 21-hydroxylase deficiency is a monogenic disorder of adrenal steroidogenesis. To prevent genital ambiguity, in girls, prenatal dexamethasone treatment is administered early in the first trimester. Prenatal genetic diagnosis of CAH and fetal sex determination identify affected female fetuses at risk for genital virilization. Advancements in prenatal diagnosis are owing to improved understanding of the genetic basis of CAH and improved technology. Cloning of the CYP21A2 gene ushered in molecular genetic analysis as the current standard of care. Noninvasive prenatal diagnosis allows for targeted treatment and avoids unnecessary treatment of males and unaffected females.

Experts' Opinion on the Prenatal Therapy of Congenital Adrenal Hyperplasia (CAH) Due to 21-Hydroxylase Deficiency - Guideline of DGKED in cooperation with DGGG (S1-Level, AWMF Registry No. 174/013, July 2015)

Purpose: This guideline of the German Society of Pediatric Endocrinology and Diabetology (DGKED) is designed to be experts' opinion on the current concept of prenatal therapy for congenital adrenal hyperplasia due to 21-hydroxylase deficiency (CAH). Several scientific medical societies have also participated in the guideline. It aims to offer guidance to physicians when they counsel affected families about prenatal therapy. Methods: The experts commissioned by the medical societies developed a consensus in an informal process. The consensus was subsequently confirmed by the steering committees of the respective medical societies. Recommendations: Prenatal CAH therapy is an experimental therapy. We recommend designing and using standardized protocols for the prenatal diagnosis, therapy and long-term follow-up of women and children treated prenatally with dexamethasone. If long-term follow-up is not possible, then prenatal therapy should not be performed.