Leukoencephalopathy in 21-beta hydroxylase deficiency: report of a family

Glucocorticoids and cognitive function: a walkthrough in endogenous and exogenous alterations

PURPOSE

The hypothalamic-pituitary-adrenal (HPA) axis exerts many actions on the central nervous system (CNS) aside from stress regulation. Glucocorticoids (GCs) play an important role in affecting several cognitive functions through the effects on both glucocorticoid (GR) and mineralocorticoid receptors (MR). In this review, we aim to unravel the spectrum of cognitive dysfunction secondary to derangement of circulating levels of endogenous and exogenous glucocorticoids.

METHODS

All relevant human prospective and retrospective studies published up to 2022 in PubMed reporting information on HPA disorders, GCs, and cognition were included.

RESULTS

Cognitive impairment is commonly found in GC-related disorders. The main brain areas affected are the hippocampus and pre-frontal cortex, with memory being the most affected domain. Disease duration, circadian rhythm disruption, circulating GCs levels, and unbalanced MR/GR activation are all risk factors for cognitive decline in these patients, albeit with conflicting data among different conditions. Lack of normalization of cognitive dysfunction after treatment is potentially attributable to GC-dependent structural brain alterations, which can persist even after long-term remission.

CONCLUSION

The recognition of cognitive deficits in patients with GC-related disorders is challenging, often delayed, or mistaken. Prompt recognition and treatment of underlying disease may be important to avoid a long-lasting impact on GC-sensitive areas of the brain. However, the resolution of hormonal imbalance is not always followed by complete recovery, suggesting irreversible adverse effects on the CNS, for which there are no specific treatments. Further studies are needed to find the mechanisms involved, which may eventually be targeted for treatment strategies.

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.

White Matter Microstructural Differences in Youth With Classical Congenital Adrenal Hyperplasia

CONTEXT

Gray matter morphology in the prefrontal cortex and subcortical regions, including the hippocampus and amygdala, are affected in youth with classical congenital adrenal hyperplasia (CAH). It remains unclear if white matter connecting these aforementioned brain regions is compromised in youth with CAH.

OBJECTIVE

To examine brain white matter microstructure in youth with CAH compared to controls.

DESIGN

A cross-sectional sample of 23 youths with CAH due to 21-hydroxylase deficiency (12.9 ± 3.5 year; 61% female) and 33 healthy controls (13.1 ± 2.8 year; 61% female) with 3T multishell diffusion-weighted magnetic resonance brain scans.

MAIN OUTCOME MEASURES

Complementary modeling approaches, including diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI), to examine in vivo white matter microstructure in six white matter tracts that innervate the prefrontal and subcortical regions.

RESULTS

DTI showed CAH youth had lower fractional anisotropy in both the fornix and stria terminalis and higher mean diffusivity in the fornix compared to controls. NODDI modeling revealed that CAH youth have a significantly higher orientation dispersion index in the stria terminalis compared to controls. White matter microstructural integrity was associated with smaller hippocampal and amygdala volumes in CAH youth.

CONCLUSIONS

These patterns of microstructure reflect less restricted water diffusion likely due to less coherency in oriented microstructure. These results suggest that white matter microstructural integrity in the fornix and stria terminalis is compromised and may be an additional related brain phenotype alongside affected hippocampus and amygdala neurocircuitry in individuals with CAH.

Brain Differences in the Prefrontal Cortex, Amygdala, and Hippocampus in Youth with Congenital Adrenal Hyperplasia

CONTEXT

Classical congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency results in hormone imbalances present both prenatally and postnatally that may impact the developing brain.

OBJECTIVE

To characterize gray matter morphology in the prefrontal cortex and subregion volumes of the amygdala and hippocampus in youth with CAH as compared to controls.

DESIGN

A cross-sectional study of 27 CAH youth (16 female; 12.6 ± 3.4 years) and 35 typically developing, healthy controls (20 female; 13.0 ± 2.8 years) with 3-T magnetic resonance imaging scans. Brain volumes of interest included bilateral prefrontal cortex and 9 amygdala and 6 hippocampal subregions. Between-subject effects of group (CAH vs. control) and sex, and their interaction (group-by-sex) on brain volumes, were studied while controlling for intracranial volume (ICV) and group differences in body mass index and bone age.

RESULTS

Congenital adrenal hyperplasia youth had smaller ICV and increased cerebrospinal fluid volume compared to controls. In fully-adjusted models, CAH youth had smaller bilateral superior and caudal middle frontal volumes, and smaller left lateral orbitofrontal volumes compared to controls. Medial temporal lobe analyses revealed that the left hippocampus was smaller in fully-adjusted models. Congenital adrenal hyperplasia youth also had significantly smaller lateral nucleus of the amygdala and hippocampal subiculum and CA1 subregions.

CONCLUSIONS

This study replicates previous findings of smaller medial temporal lobe volumes in CAH patients and suggests that the lateral nucleus of the amygdala, as well as subiculum and subfield CA1 of the hippocampus, are particularly affected within the medial temporal lobes in CAH youth.

Cognitive function in children with classic congenital adrenal hyperplasia

Studies of cognitive function in patients with congenital adrenal hyperplasia (CAH) are few and controversial. This study aimed to investigate general intelligence and specific cognitive functions in children with salt wasting (SW) form of CAH and their relationship to demographic, clinical, and laboratory variables. This study included 36 children with classic 21 hydroxylase deficiency SW type of CAH (males = 12; females = 24; mean age = 15.6 ± 2.3 years). Intelligence quotient (IQ) and cognition were assessed using Wechsler Intelligence Scale for Children 3rd edition (WISC-III) and Stanford Binet Subsets Test version 4 (SBST4). Compared to controls, patients had lower mean full-scale (FS) IQ (P = 0.01) score, particularly performance IQ score (P = 0.001), and comprehension, pattern analysis, quantitation, bead memory, and memory for sentences of SBST4 (P = 0.05, P = 0.014, P = 0.001, P = 0.002, and P = 0.05, respectively). Lower IQ was observed in poorly controlled compared with well-controlled patients on medical treatment. Significant correlations were observed between FSIQ with age (r = - 0.810; P = 0.001), duration of treatment (r = - 0.887; P = 0.01), dose of glucocorticoids (r = - 0.463; P = 0.01), 17-OHP (r = - 0.543; P = 0.01) and testosterone (r = - 0.462; P = - 0.006) levels, and number of hyponatremic episodes (r = - 0.350; P = 0.05). In multivariate analysis, the independent risks of low FSIQ were the dose of glucocorticoids (OR = 1.14; 95% CI = 1.08-1.23, P = 0.0001), 17-OHP levels (OR = 2.25; 95% CI = 1.19-2.85, P = 0.01), and number of hyponatremic episodes (OR = 4.34; 95% CI = 2.05-5.15, P = 0.01).Conclusion: Patients with SW form of CAH may have lower IQ and cognitive deficits which may be related to the dose of glucocorticoids, androgen excess, and number of hyponatremic episodes. What is Known: • Congenital adrenal hyperplasia (CAH) is a group of inherited impairment of cortisol biosynthesis. • Studies of cognitive function in patients with congenital adrenal hyperplasia (CAH) are few and controversial. What is New: • Children with CAH may have lower intelligent quotient (IQ) and cognitive deficits. • Early hyponatremic episodes, overtreatment with glucocorticoids, and high androgen levels may be possible causative factors for the cognitive deficits.

Brain white matter abnormality in a newborn infant with congenital adrenal hyperplasia

Several studies have described brain white matter abnormalities on magnetic resonance imaging (MRI) in children and adults with congenital adrenal hyperplasia (CAH), while the brain MRI findings of newborn infants with CAH have not been clarified. We report a newborn boy with CAH who presented brain white matter abnormality on MRI. He was diagnosed as having salt-wasting CAH with a high 17-OHP level at neonatal screening and was initially treated with hydrocortisone at 8 days of age. On day 11 after birth, he had a generalized tonic seizure. No evidence of serum electrolyte abnormalities was observed. Brain MRI revealed white matter abnormalities that consisted of bilateral small diffuse hyperintensities on T1-weighted images with slightly low intensity on T2-weighted images in the watershed area. Several factors associated with brain white matter abnormalities in adults with CAH, such as increasing age, hypertension, diabetes and corticosteroid replacement, were not applicable. Although the cause of the phenomenon in this case is unclear, brain white matter abnormality could be observed in newborn infants with CAH as well as in adult patients.

Brain white matter abnormality in a newborn infant with congenital adrenal hyperplasia

Several studies have described brain white matter abnormalities on magnetic resonance imaging (MRI) in children and adults with congenital adrenal hyperplasia (CAH), while the brain MRI findings of newborn infants with CAH have not been clarified. We report a newborn boy with CAH who presented brain white matter abnormality on MRI. He was diagnosed as having salt-wasting CAH with a high 17-OHP level at neonatal screening and was initially treated with hydrocortisone at 8 days of age. On day 11 after birth, he had a generalized tonic seizure. No evidence of serum electrolyte abnormalities was observed. Brain MRI revealed white matter abnormalities that consisted of bilateral small diffuse hyperintensities on T1-weighted images with slightly low intensity on T2-weighted images in the watershed area. Several factors associated with brain white matter abnormalities in adults with CAH, such as increasing age, hypertension, diabetes and corticosteroid replacement, were not applicable. Although the cause of the phenomenon in this case is unclear, brain white matter abnormality could be observed in newborn infants with CAH as well as in adult patients.

Advances in the diagnosis of leukoencephalopathies

Introduction : Leukoencephalopathies (LEs) are a diverse group of diseases involving cerebral white matter. Some of the disorders may be infectious or immunologically mediated and, therefore, tend to be more amenable to treatment. Most of these disorders have a genetic basis, for which genetic counseling becomes important as currently very few of them have effective therapies. Areas covered : This review calls attention to the diagnostic dilemmas, highlights the diagnostic tests of choice for separating conditions with similar clinical, laboratory or neuroimaging findings, and describes several LEs that have been newly discovered within the last 20 years. Imaging of LEs has progressed rapidly since the introduction of magnetic resonance imaging (MRI) and spectroscopy (MRS), allowing recognition of new diseases, with and without identifiable corresponding biochemical or genetic defects. The distinguishing MRI and MRS features of LEs are described, as well as the resources available for biochemical, CSF and blood sample testing for diagnosis and differentiation from previously known LEs. Expert opinion : Although there is no treatment at present for many of the LEs, their detection as a cause of intellectual and motor disabilities, and as inherited disorders, makes it necessary to accurately categorize them. This knowledge will then allow further elucidation of the etiology, understanding the biological underpinnings, and eventually progress toward rational therapies.

Congenital adrenal hyperplasia and brain magnetic resonance imaging abnormalities

A 15-yr-old male patient with congenital adrenal hyperplasia (CAH) was referred to our department with a one year history of gradual worsening of tremors. He was diagnosed with salt-wasting 21-hydroxylase deficiency CAH at 40 d old and was started on hydrocortisone, fludrocortisone and salt. He was found to have hypertension at 8 yr of age. Detailed investigations failed to detect any cause for secondary hypertension. Physical findings on the current hospitalization objectified obesity, blood pressure of 150/80 mmHg, postural and action tremor, left cerebellar syndrome, reflex tetra pyramidal syndrome and mental decline. Brain magnetic resonance imaging (MRI) showed bilateral periventricular white matter hyperintensity that was more pronounced in the posterior regions and associated with cortico-subcortical atrophy and complete agenesis of the corpus callosum. All investigations for leukoencephalopathy were negative. A diagnosis of brain MRI abnormalities related to CAH was made, and the patient received symptomatic treatment of tremors. Our case report provides evidence of an increased frequency of brain MRI abnormalities in CAH. The literature suggests hormonal imbalance and exposure to excess exogenous glucocorticoids as main probable mechanisms. Thus, in clinical practice, CAH should be considered as one of the possible causes of brain white matter involvement associated with or without cerebral atrophy.