Failure of steroid replacement to consistently normalize pituitary function in congenital adrenal hyperplasia: hormonal and MRI data

Altered Emotion Perception Linked to Structural Brain Differences in Youth With Congenital Adrenal Hyperplasia

CONTEXT

Congenital adrenal hyperplasia (CAH) is a genetic disorder that results in hormonal imbalances and decreased brain volumes in regions important for emotional processing.

OBJECTIVE

To examine whether emotion perception differs between youth with CAH and control youth, and if these differences relate to brain volumes.

METHODS

In this cross-sectional study of 27 youths with CAH (mean age = 12.63 years, 16 female) and 35 age- and sex-matched controls (mean age = 13.03 years, 20 female), each participant rated picture stimuli and completed a 3T structural brain scan. Valence and arousal ratings and reaction times of 61 affective images were assessed. Gray matter volumes were measured by MRI.

RESULTS

Youth with CAH had lower valence ratings for negative (P = .007) and neutral (P = .019) images. Controls showed differences in reaction times and arousal ratings across stimuli conditions, but youth with CAH did not. Brain volumes of the right amygdala (P = .025) and left hippocampus (P = .002) were associated with valence ratings. Left rostral middle frontal (P < .001) and right medial orbitofrontal cortex (P = .002) volumes were negatively related to valence scores only in youth with CAH, whereas left medial orbitofrontal cortex (P < .001) volumes were associated with valence scores positively in youth with CAH and negatively in controls.

CONCLUSION

Findings suggest that youth with CAH perceive emotive stimuli as more unpleasant. Decreased brain volumes in the amygdala, hippocampus, and prefrontal cortex are associated with these measures of altered emotion perception in youth with CAH.

Congenital Adrenal Hyperplasia and Brain Health: A Systematic Review of Structural, Functional, and Diffusion Magnetic Resonance Imaging (MRI) Investigations

BACKGROUND

Congenital adrenal hyperplasia (CAH) is a group of genetic disorders that affects the adrenal glands and is the most common cause of primary adrenal insufficiency in children. In the past few decades, magnetic resonance imaging (MRI) has been implemented to investigate how the brain may be affected by CAH. A systematic review was conducted to evaluate and synthesize the reported evidence of brain findings related to CAH using structural, functional, and diffusion-weighted MRI.

METHODS

We searched bibliographical databases through July 2021 for brain MRI studies in individuals with CAH.

RESULTS

Twenty-eight studies were identified, including 13 case reports or series, 10 studies that recruited and studied CAH patients vs unaffected controls, and 5 studies without a matched control group. Eleven studies used structural MRI to identify structural abnormalities or quantify brain volumes, whereas 3 studies implemented functional MRI to investigate brain activity, and 3 reported diffusion MRI findings to assess white matter microstructure. Some commonly reported findings across studies included cortical atrophy and differences in gray matter volumes, as well as white matter hyperintensities, altered white matter microstructure, and distinct patterns of emotion and reward-related brain activity.

CONCLUSIONS

These findings suggest differences in brain structure and function in patients with CAH. Limitations of these studies highlight the need for CAH neuroimaging studies to incorporate larger sample sizes and follow best study design and MRI analytic practices, as well as clarify potential neurologic effects seen across the lifespan and in relation to clinical and behavioral CAH phenotypes.

The role of imaging in congenital adrenal hyperplasia

Congenital adrenal hyperplasia (CAH) is an autossomic recessive disorder caused by impaired steroidogenesis. Patients with CAH may present adrenal insufficiency with or without salt-wasting, as well as various degrees of virilization and fertility impairment, carrying a high incidence of testicular adrenal rest tumors and increased incidence of adrenal tumors. The diagnosis of CAH is made based on the adrenocortical profile hormonal evaluation and genotyping, in selected cases. Follow-up is mainly based on hormonal and clinical evaluation. Utility of imaging in this clinical setting may be helpful for the diagnosis, management, and follow-up of the patients, although recommendations according to most guidelines are weak when present. Thus, the authors aimed to conduct a narrative synthesis of how imaging can help in the management of patients with CAH, especially focused on genitography, ultrasonography, computed tomography, and magnetic resonance imaging.

Clinical outcomes in the management of congenital adrenal hyperplasia

Congenital adrenal hyperplasia (CAH) is a group of disorders affecting adrenal steroid synthesis. The most common form, 21-hydroxylase deficiency, leads to decreased production of cortisol and aldosterone with increased androgen secretion. In classic CAH glucocorticoid treatment can be life-saving, and provides symptom control, but must be given in an unphysiological manner with the risk of negative long-term outcomes. A late diagnosis or a severe phenotype or genotype has also a negative impact. These factors can result in impaired quality of life (QoL), increased cardiometabolic risk, short stature, osteoporosis and fractures, benign tumors, decreased fertility, and vocal problems. The prognosis has improved during the last decades, thanks to better clinical management and nowadays the most affected patients seem to have a good QoL. Very few patients above the age of 60 years have, however, been studied. Classifying patients according to genotype may give additional useful clinical information. The introduction of neonatal CAH screening may enhance long-term results. Monitoring of different risk factors and negative consequences should be done regularly in an attempt to improve clinical outcomes further.

Congenital adrenal hyperplasia owing to 21-hydroxylase deficiency

Congenital adrenal hyperplasia (CAH) owing to 21-hydroxylase deficiency is the most common cause of genital ambiguity in the newborn and is present in about 1 in 15,000 live births worldwide. The disease is further characterized in its classic salt-wasting form (approximately 75% of cases) by potentially lethal adrenal insufficiency. A non-salt-wasting form of classic CAH with 21-hydroxylase deficiency is also recognized by genital ambiguity in affected females and by signs of androgen excess in later childhood in males. Nonclassic CAH with 21-hydroxylase deficiency may be detected in 1% to 3% of populations and is often mistaken for idiopathic precocious pubarche in children or polycystic ovary syndrome in young women. This article presents an overview of clinical and genetic aspects of the various forms of CAH with 21-hydroxylase deficiency.

Congenital adrenal hyperplasia due to 21-hydroxylase deficiency

More than 90% of cases of congenital adrenal hyperplasia (CAH, the inherited inability to synthesize cortisol) are caused by 21-hydroxylase deficiency. Females with severe, classic 21-hydroxylase deficiency are exposed to excess androgens prenatally and are born with virilized external genitalia. Most patients cannot synthesize sufficient aldosterone to maintain sodium balance and may develop potentially fatal "salt wasting" crises if not treated. The disease is caused by mutations in the CYP21 gene encoding the steroid 21-hydroxylase enzyme. More than 90% of these mutations result from intergenic recombinations between CYP21 and the closely linked CYP21P pseudogene. Approximately 20% are gene deletions due to unequal crossing over during meiosis, whereas the remainder are gene conversions--transfers to CYP21 of deleterious mutations normally present in CYP21P. The degree to which each mutation compromises enzymatic activity is strongly correlated with the clinical severity of the disease in patients carrying it. Prenatal diagnosis by direct mutation detection permits prenatal treatment of affected females to minimize genital virilization. Neonatal screening by hormonal methods identifies affected children before salt wasting crises develop, reducing mortality from this condition. Glucocorticoid and mineralocorticoid replacement are the mainstays of treatment, but more rational dosing and additional therapies are being developed.

Magnetic resonance imaging in the congenital adrenal hyperplasia population: increased frequency of white-matter abnormalities and temporal lobe atrophy

Congenital adrenal hyperplasia results from an adrenal enzyme deficiency, that causes an underproduction of glucocorticoids and sometimes mineralocorticoids and a resultant overproduction of androgens, until treatment with replacement glucocorticoids is instituted. The goal of this study was to determine the frequency and etiology of white-matter changes and temporal lobe atrophy demonstrable on magnetic resonance imaging (MRI) in a group of children and young adults with congenital adrenal hyperplasia. About one third of the patients evidenced white-matter abnormalities or temporal lobe atrophy. All patients, except one with a known stroke, had normal neurologic examinations. Exposure to excess exogenous glucocorticoids in the process of being treated for congenital adrenal hyperplasia is the most theoretically appealing explanation for these MRI findings. However, the relationship of MRI findings to treatment status (over-versus under-suppressed) does not run in clear parallel.