Aromatase Inhibitor Increases the Height of Patients with Congenital Adrenal Hyperplasia Due to 21-Hydroxylase Deficiency

Anastrozole Improves Height Outcomes in Growing Children With Congenital Adrenal Hyperplasia Due to 21-hydroxylase Deficiency

BACKGROUND

Hyperandrogenemia resulting in estrogen-mediated accelerated bone maturation and early growth plate fusion contributes to short stature in children with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency. Aromatase inhibitors block androgen conversion to estrogen and have been used off-label in children with short stature to improve adult height. There are no adequately powered studies examining the use of aromatase inhibitors in children with CAH with advanced bone age and reduced predicted adult height.

METHODS

Records of CAH patients treated with anastrozole were reviewed. Z-scores of bone age, predicted adult height, and height corrected for bone age were examined over an 8-year period. Outcome changes were analyzed using weighted mixed-effects models, adjusting for sex, diagnosis, age at diagnosis, and average hydrocortisone dose before and during treatment with anastrozole.

RESULTS

In 60 patients (26 females; 52 classic, 8 nonclassic) started on anastrozole therapy, the mean bone age Z-score decreased from 4.2 to 2.0 at 4 years and 1.3 at 6 years (both P < .001); predicted adult height Z-score improved from -2.1 to -0.45 at 4 years and 0.18 at 6 years (both P < .001); corrected height Z-scores improved from -1.7 to -0.33 at 4 years and 0.18 at 6 years (P < .001). There was no significant difference in the average total daily hydrocortisone dose used before or during treatment.

CONCLUSION

Anastrozole decreased the rate of bone maturation and led to improved height outcomes, indicating that anastrozole could have a role as an adjunct therapy in children with CAH and advanced bone age.

Decoding Monogenic Hypertension: A Review of Rare Hypertension Disorders

BACKGROUND

Hypertension is a growing concern worldwide, with increasing prevalence rates in both children and adults. Most cases of hypertension are multifactorial, with various genetic, environmental, socioeconomic, and lifestyle influences. However, monogenic hypertension, a blanket term for a group of rare hypertensive disorders, is caused by single-gene mutations that are typically inherited in an autosomal dominant fashion, and ultimately disrupt normal blood pressure regulation in the kidney or adrenal gland. Being able to recognize and understand the pathophysiology of these rare disorders is critical for properly diagnosing hypertension, particularly in children and young adults, as treating each form of monogenic hypertension requires specific and targeted treatment approaches.

METHODS

A scoping literature review was conducted on the available knowledge regarding each of the disorders currently categorized as forms of monogenic hypertension.

RESULTS

This narrative review serves to highlight the epidemiology, pathophysiology, clinical presentation, recent case reports, and most current methods of evaluation and treatment for familial hyperaldosteronism types 1-4, Gordon syndrome. Liddle syndrome, syndrome of apparent mineralocorticoid excess, congenital adrenal hyperplasia, Geller syndrome, hereditary syndromes related to pheochromocytomas and paragangliomas, and brachydactyly type E.

CONCLUSIONS

Recent and future advances in genetic analysis techniques will further enhance the diagnosis and early management of these disorders, preventing the consequences of uncontrolled hypertension.

Approach to the Child and Adolescent With Adrenal Insufficiency

The management of adrenal insufficiency (AI) is challenging, and the overall goals of treatment are to prevent life-threatening adrenal crises, to optimize linear growth, to control androgen levels without overdosing in patients with congenital adrenal hyperplasia (CAH), and to improve quality of life in affected individuals. Standard glucocorticoid formulations fail to replicate the circadian rhythm of cortisol and control the adrenal androgen production driven by adrenocorticotropin. To personalize and tailor glucocorticoid therapy and to improve patient outcomes, new pharmacological strategies have been developed that best mimic physiological cortisol secretion. Novel therapeutic approaches in the management of AI include new ways to deliver circadian cortisol replacement as well as various adjunctive therapies to reduce androgen production and/or androgen action/effects. Preclinical studies are exploring the role of restorative cell-based therapies, and a first recombinant adeno-associated virus-based gene therapy is also being developed in humans with CAH. In this article, we present 3 illustrative cases of AI with different underlying etiologies and times of presentation. Diagnostic and management processes are discussed with an emphasis on treatment and outcomes. We have also provided the most up-to-date evidence for the tailored management of children and adolescents with AI.

Clinical Manifestations and Treatment Challenges in Infants and Children With Classic Congenital Adrenal Hyperplasia Due to 21-Hydroxylase Deficiency

The most common form of congenital adrenal hyperplasia (CAH) is secondary to 21-hydroxylase deficiency (21OHD). This review will summarize the clinical manifestations, recommended treatments, monitoring, clinical challenges and management strategy, and treatment challenges in special situations for infants and children with classic CAH due to 21OHD. Specifically, we review newborn screening and the initial diagnosis, glucocorticoid and mineralocorticoid treatment, and recommended monitoring, including anthropometric and laboratory measures. Children with CAH may have premature adrenarche, precocious puberty, and early growth plate closure and have an increased risk of hypertension and overweight/obesity. Many 46,XX individuals will also have genital differences, which may include clitoromegaly and/or a urogenital sinus. We review psychosocial and surgical considerations, including suggestions on how to talk with children, family, and caregivers about bodily difference. These suggestions may be used by families and/or providers caring for individuals with CAH.

Case Report: Anastrozole as a monotherapy for pre-pubertal children with non-classic congenital adrenal hyperplasia

Most children with non-classic congenital adrenal hyperplasia (NC-CAH) due to 21-hydroxylase deficiency are asymptomatic and do not require cortisol replacement therapy unless they develop symptoms of hyperandrogenemia. The current practice is to treat symptomatic children with hydrocortisone aimed at suppressing excess adrenal androgen production irrespective of the child's level of endogenous cortisol production. Once on hydrocortisone therapy, even children with normal cortisol production require stress dosing. Some children with NC-CAH may present with premature adrenarche, growth acceleration, and advanced bone age, but with no signs of genital virilization and normal endogenous cortisol production. In these cases, an alternative therapy to hydrocortisone treatment that does not impact the hypothalamic-pituitary-adrenal axis, but targets increased estrogen production and its effects on bone maturation, could be considered. Aromatase inhibitors (AIs), which block the aromatization of androgen to estrogen, have been used off-label in men with short stature to delay bone maturation and as an adjunct therapy in children with classic CAH. The use of AI as a monotherapy for children with NC-CAH has never been reported. We present three pre-pubertal female children with a diagnosis of NC-CAH treated with anastrozole monotherapy after presenting with advanced bone age, early adrenarche, no signs of genital virilization, and normal peak cortisol in response to ACTH stimulation testing. Bone age z-scores normalized, and all three reached or exceeded their target heights. Monotherapy with anastrozole can be an effective alternative in slowing down bone maturation and improving height outcomes in children with NC-CAH and normal adrenal cortisol production.

Should Skeletal Maturation Be Manipulated for Extra Height Gain?

Skeletal maturation can be delayed by reducing the exposure to estrogens, either by halting pubertal development through administering a GnRH analogue (GnRHa), or by blocking the conversion of androgens to estrogens through an aromatase inhibitor (AI). These agents have been investigated in children with growth disorders (off-label), either alone or in combination with recombinant human growth hormone (rhGH). GnRHa is effective in attaining a normal adult height (AH) in the treatment of children with central precocious puberty, but its effect in short children with normal timing of puberty is equivocal. If rhGH-treated children with growth hormone deficiency or those who were born small-for-gestational age are still short at pubertal onset, co-treatment with a GnRHa for 2-3 years increases AH. A similar effect was seen by adding rhGH to GnRHa treatment of children with central precocious puberty with a poor AH prediction and by adding rhGH plus GnRHa to children with congenital adrenal hyperplasia with a poor predicted adult height on conventional treatment with gluco- and mineralocorticoids. In girls with idiopathic short stature and relatively early puberty, rhGH plus GnRHa increases AH. Administration of letrozole to boys with constitutional delay of growth puberty may increase AH, and rhGH plus anastrozole may increase AH in boys with growth hormone deficiency or idiopathic short stature, but the lack of data on attained AH and potential selective loss-of-follow-up in several studies precludes firm conclusions. GnRHas appear to have a good overall safety profile, while for aromatase inhibitors conflicting data have been reported.