Emerging treatment for congenital adrenal hyperplasia

AAV-delivered hepato-adrenal cooperativity in steroidogenesis: Implications for gene therapy for congenital adrenal hyperplasia

Despite the availability of life-saving corticosteroids for 70 years, treatment for adrenal insufficiency is not able to recapitulate physiological diurnal cortisol secretion and results in numerous complications. Gene therapy is an attractive possibility for monogenic adrenocortical disorders such as congenital adrenal hyperplasia; however, requires further development of gene transfer/editing technologies and knowledge of the target progenitor cell populations. Vectors based on adeno-associated virus are the leading system for direct in vivo gene delivery but have limitations in targeting replicating cell populations such as in the adrenal cortex. One strategy to overcome this technological limitation is to deliver the relevant adrenocortical gene to a currently targetable organ outside of the adrenal cortex. To explore this possibility, we developed a vector encoding human 21-hydroxylase and directed expression to the liver in a mouse model of congenital adrenal hyperplasia. This extra-adrenal expression resulted in reconstitution of the steroidogenic pathway. Aldosterone and renin levels normalized, and corticosterone levels improved sufficiently to reduce adrenal hyperplasia. This strategy could provide an alternative treatment option for monogenic adrenal disorders, particularly for mineralocorticoid defects. These findings also demonstrate, when targeting the adrenal gland, that inadvertent liver transduction should be precluded as it may confound data interpretation.

Risk factors for testicular adrenal rest tumors in pediatric patients with congenital adrenal hyperplasia

INTRODUCTION

Testicular adrenal rest tumors (TARTs) predominantly occur in patients with congenital adrenal hyperplasia (CAH) and may interfere with the function of the testicles.

OBJECTIVE

This study aimed to identify the factors that contribute to the occurrence of TARTs in patients with CAH and influence their volume.

STUDY DESIGN

This was a comparative cross-sectional study. Male patients aged 0-16 years with CAH were included. Weight, height, bone age determination, biochemical and androgenic profiles, and testicular ultrasound were performed. Patients were divided into those with and without TARTs and the between-group differences were assessed using the Mann-Whitey U test and Fisher's exact test. A ROC curve was created for serum ACTH levels to identify the cut-off point to diagnose TARTs. Variables that influenced the volume of the TARTs were identified using Spearman's correlation coefficient.

RESULTS

TARTs were observed in seven (19.4%) of 36 male children with CAH. Of the patients with TARTs, 85.7% were pubertal. Serum concentrations of adrenocorticotropic hormone (ACTH) levels were significantly higher in patients with TARTs than in those without (309.0 pg/mL vs. 45.2 pg/mL; p = 0.006). ACTH levels >200 pg/mL were found to predict the presence of TARTs (sensitivity 85.7%; specificity 86.2%) (Figure). The factors found to correlate with TARTs volume were ACTH levels (coefficient 0.004; p = 0.009) and the three-year average of serum testosterone levels (coefficient 9.64; p = 0.003).] DISCUSSION: The main limitation of this study was the small sample size. However, an ACTH cut-off point to predict insufficient hormonal treatment and consequently the presence of TART had not been described.

CONCLUSIONS

High ACTH (>200 pg/mL) was found to be predictive insufficient hormonal treatment in patients with CAH. The three-year average of serum testosterone levels and ACTH concentrations were correlated with the volume of TARTs.

Future directions for adrenal insufficiency: cellular transplantation and genetic therapies

Primary adrenal insufficiency occurs in 1 in 5-7000 adults. Leading aetiologies are autoimmune adrenalitis in adults and congenital adrenal hyperplasia (CAH) in children. Oral replacement of cortisol is lifesaving, but poor quality of life, repeated adrenal crises and dosing uncertainty related to lack of a validated biomarker for glucocorticoid sufficiency, persists. Adrenocortical cell therapy and gene therapy may obviate many of the shortcomings of adrenal hormone replacement. Physiological cortisol secretion regulated by pituitary adrenocorticotropin, could be achieved through allogeneic adrenocortical cell transplantation, production of adrenal-like steroidogenic cells from either stem cells or lineage conversion of differentiated cells, or for CAH, gene therapy to replace or repair a defective gene. The adrenal cortex is a high turnover organ and thus failure to incorporate progenitor cells within a transplant will ultimately result in graft exhaustion. Identification of adrenocortical progenitor cells is equally important in gene therapy where new genetic material must be specifically integrated into the genome of progenitors to ensure a durable effect. Delivery of gene editing machinery and a donor template, allowing targeted correction of the 21-hydroxylase gene, has the potential to achieve this. This review describes advances in adrenal cell transplants and gene therapy that may allow physiological cortisol production for children and adults with primary adrenal insufficiency.

Approach of Heterogeneous Spectrum Involving 3beta-Hydroxysteroid Dehydrogenase 2 Deficiency

We aim to review data on 3beta-hydroxysteroid dehydrogenase type II (3βHSD2) deficiency. We identified 30 studies within the last decade on PubMed: 1 longitudinal study (N = 14), 2 cross-sectional studies, 1 retrospective study (N = 16), and 26 case reports (total: 98 individuals). Regarding geographic area: Algeria (N = 14), Turkey (N = 31), China (2 case reports), Morocco (2 sisters), Anatolia (6 cases), and Italy (N = 1). Patients’ age varied from first days of life to puberty; the oldest was of 34 y. Majority forms displayed were salt-wasting (SW); some associated disorders of sexual development (DSD) were attendant also—mostly 46,XY males and mild virilisation in some 46,XX females. SW pushed forward an early diagnosis due to severity of SW crisis. The clinical spectrum goes to: premature puberty (80%); 9 with testicular adrenal rest tumours (TARTs); one female with ovarian adrenal rest tumours (OARTs), and some cases with adrenal hyperplasia; cardio-metabolic complications, including iatrogenic Cushing’ syndrome. More incidental (unusual) associations include: 1 subject with Barter syndrome, 1 Addison’s disease, 2 subjects of Klinefelter syndrome (47,XXY/46,XX, respective 47,XXY). Neonatal screening for 21OHD was the scenario of detection in some cases; 17OHP might be elevated due to peripheral production (pitfall for misdiagnosis of 21OHD). An ACTH stimulation test was used in 2 studies. Liquid chromatography tandem–mass spectrometry unequivocally sustains the diagnostic by expressing high baseline 17OH-pregnenolone to cortisol ratio as well as 11-oxyandrogen levels. HSD3B2 gene sequencing was provided in 26 articles; around 20 mutations were described as “novel pathogenic mutation” (frameshift, missense or nonsense); many subjects had a consanguineous background. The current COVID-19 pandemic showed that CAH-associated chronic adrenal insufficiency is at higher risk. Non-adherence to hormonal replacement contributed to TARTs growth, thus making them surgery candidates. To our knowledge, this is the largest study on published cases strictly concerning 3βHSD2 deficiency according to our methodology. Adequate case management underlines the recent shift from evidence-based medicine to individualized (patient-oriented) medicine, this approach being particularly applicable in this exceptional and challenging disorder.