Central precocious puberty in a patient with X-linked adrenal hypoplasia congenita and Xp21 contiguous gene deletion syndrome

Nuclear Receptor Gene Variants Underlying Disorders/Differences of Sex Development through Abnormal Testicular Development

Gonadal development is the first step in human reproduction. Aberrant gonadal development during the fetal period is a major cause of disorders/differences of sex development (DSD). To date, pathogenic variants of three nuclear receptor genes (NR5A1, NR0B1, and NR2F2) have been reported to cause DSD via atypical testicular development. In this review article, we describe the clinical significance of the NR5A1 variants as the cause of DSD and introduce novel findings from recent studies. NR5A1 variants are associated with 46,XY DSD and 46,XX testicular/ovotesticular DSD. Notably, both 46,XX DSD and 46,XY DSD caused by the NR5A1 variants show remarkable phenotypic variability, to which digenic/oligogenic inheritances potentially contribute. Additionally, we discuss the roles of NR0B1 and NR2F2 in the etiology of DSD. NR0B1 acts as an anti-testicular gene. Duplications containing NR0B1 result in 46,XY DSD, whereas deletions encompassing NR0B1 can underlie 46,XX testicular/ovotesticular DSD. NR2F2 has recently been reported as a causative gene for 46,XX testicular/ovotesticular DSD and possibly for 46,XY DSD, although the role of NR2F2 in gonadal development is unclear. The knowledge about these three nuclear receptors provides novel insights into the molecular networks involved in the gonadal development in human fetuses.

Pleomorphism of the HPG axis with NR0B1 gene mutation - a case report of longitudinal follow-up of a proband with central precocious puberty

OBJECTIVES

X-linked adrenal hypoplasia congenita (AHC) is characterized by adrenal insufficiency and hypogonadotropic hypogonadism. Herein, we report a rare case of X-linked AHC with central precocious puberty (CPP).

CASE PRESENTATION

An 11-month-old male patient was found to have premature pubarche, enlargement of the penis, and frequent erection. LH and FSH levels after the GnRHa test were in the pubertal range. Direct sequencing revealed a heterozygous variant of the NR0B1 gene. The proband was treated with hydrocortisone and 9-alpha fludrocortisone because of the significantly elevated ACTH and renin activity. The secondary sexual characteristics relieved gradually. The serum testosterone and LH subsequently returned to the prepubertal range. The basal serum FSH values have been between 1.0 and 2.0 IU/L since the age of 2.25 years, with extremely low AMH levels beginning at 3 years.

CONCLUSIONS

The clinical course of CPP with NR0B1 variant may be temporary. HPG axis status of X-linked AHC may probably be pleomorphic during the longitudinal follow-up.

IL1RAPL1 Gene Deletion in a Female Patient with Developmental Delay and Continuous Spike-Wave during Sleep

Interleukin-1 receptor accessory protein-like 1 (IL1RAPL1) encodes a protein that is highly expressed in neurons and has been shown to regulate neurite outgrowth as well as synapse formation and synaptic transmission. Clinically, mutations in or deletions of IL1RAPL1 have been associated with a spectrum of neurological dysfunction including autism spectrum disorder and nonsyndromic X-linked developmental delay/intellectual disability of varying severity. Nearly all reported cases are in males; in the few reported cases involving females, the clinical presentation was mild or the deletion was identified in phenotypically normal carriers in accordance with X-linked inheritance. Using genome-wide microarray analysis, we identified a novel de novo 373 kb interstitial deletion of the X chromosome (Xp21.1-p21.2) that includes exons 4 to 6 of the IL1RAPL1 gene in an 8-year-old girl with severe intellectual disability and behavioral disorder with a history of developmental regression. Overnight continuous video electroencephalography revealed electrical status epilepticus in sleep (ESES). This case expands the clinical genetic spectrum of IL1RAPL1-related neurodevelopmental disorders and highlights a new genetic association of ESES.

Identification of a novel point mutation in DAX-1 gene in a patient with adrenal hypoplasia congenita

X-linked adrenal hypoplasia congenita caused by a mutation in NR0B1/DAX-1 is a rare inherited disorder. Patients with adrenal hypoplasia congenita are usually diagnosed with primary adrenal insufficiency in infancy or early childhood and present hypogonadotropic hypogonadism during adolescence. Our patient first presented with adrenal crisis at the age of 2 months, which was managed with glucocorticoids and mineralocorticoids. At the age of 17 years, testicular volumes of 5 mL each and a stretched penile length of 4 cm were noted. A combined pituitary function test showed a peak luteinizing hormone level of 2.68 mIU/mL, testosterone 13.5 ng/dL, confirming hypogonadotropic hypogonadism. After whole-exome sequencing, a new variant of DAX-1, c.881T>C (p.Leu294Pro), was found. He was diagnosed with X-linked adrenal hypoplasia congenita and then treated with human choriogonadotropin for the induction of spermatogenesis as well as with steroid replacement therapy.

Gonadotropin- and Adrenocorticotropic Hormone-Independent Precocious Puberty of Gonadal Origin in a Patient with Adrenal Hypoplasia Congenita Due to DAX1 Gene Mutation - A Case Report and Review of the Literature: Implications for the Pathomechanism

BACKGROUND/AIMS

Mutations in the DAX1 gene cause X-linked adrenal hypoplasia congenita (AHC) classically associated with hypogonadotropic hypogonadism. Unexpectedly, precocious puberty (PP) has been reported in some cases, its mechanism remaining unclear.

METHODS

We longitudinally studied a boy with AHC due to DAX1 gene mutation who developed peripheral PP at age 4.5 years. Initially he presented pubic hair, penile enlargement, advanced bone age and elevated testosterone levels. PP progressed with acne, body odour and ejaculations. In addition, we summarized reported findings of patients with DAX1 mutations and PP in the literature in a structured manner providing a basis to discuss possible pathomechanisms of PP in DAX1 patients.

RESULTS

In our patient, hydrocortisone treatment was increased to 20 mg/m2/day as suggested in similar published cases. However, despite the suppression of adrenocorticotropic hormone (ACTH), this remained without clinical effect or change in laboratory results. The progression of symptoms of pubertal development was well suppressed under cyproterone acetate treatment. Twenty-four-hour steroid urine excretion rate measurements excluded an effect of adrenal androgens and showed a prepubertal rise of excreted testosterone. Testes size remained small. GnRH testing showed peripheral PP.

CONCLUSION

We hypothesize that an intrinsic, gonadotropin- and ACTH-independent activation of steroidogenesis in the DAX1 deficient testes leads to PP in AHC patients with DAX1 mutations.

Primary Adrenocortical Insufficiency Case Series in the Neonatal Period: Genetic Etiologies Are More Common Than Expected

Primary adrenocortical insufficiency (PAI) is an important cause of morbidity in neonates. The most common cause of PAI in neonates is congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21-OHD). Other rarer monogenic cases, for example, adrenal hypoplasia congenita (AHC) or familial glucocorticoid deficiency, also simulate clinical manifestation of 21-OHD, leading to misdiagnosis. The therapies and prognosis of these monogenic cases of PAI are entirely different. This study aimed to compare the differences of clinical data and identify genetic etiologies of PAI cases in the neonatal period. All 7 neonates initially presented with hyperpigmentation, hyponatremia, hyperkalemia, and high serum adrenocorticotropic hormone levels. Only CAH patients showed hyperandrogenism and remarkably elevated serum 17-hydroxyprogesterone levels. All the pathogenic mutations found in CYP21A2 were well known, except c.1069C>T (exon 8). The male patient with AHC had a novel hemizygous deletion of exon 2 in DAX1. The other one with familial glucocorticoid deficiency type 1 had two novel heterozygous mutations in the gene coding melanocortin 2 receptor, c.701C>T (exon 2) and c.119delT (exon 2). Glucocorticoid and/or mineralocorticoid replacement therapy depends on the cause of PAI. Genetic testing can be performed as a alternative diagnostic approach to provide information about therapy, prognosis, and genetic counseling.

Central precocious puberty as a prelude to hypogonadism in a patient with Klinefelter syndrome

INTRODUCTION

Incomplete pubertal development is a common phenomenon found in patients with Klinefelter syndrome (KFS). KFS combined with central precocious puberty (CPP) rarely occurs. We herein report a rare case of KFS with CPP and review several studies to determine the possible mechanism underlying this condition.

CASE PRESENTATION

An 8-year, 5-month-old male patient was admitted to our hospital because of enlargement of the penis and small testes. Laboratory evaluation revealed high luteinizing hormone and follicle-stimulating hormone levels, a high testosterone level, and the 48,XXYY karyotype. He was treated with triptorelin. One year later, the patient's testosterone level decreased and pubertal arrest occurred.

CONCLUSION

The literature review in this study showed that the occurrence of hypogonadism combined with CPP is not unique to patients with KFS; it has also been reported in individuals with Turner syndrome, adrenal hypoplasia congenita, and other diseases. Such individuals share common features including partial hypogonadism and a normal hypothalamic-pituitary-gonadal axis. CPP is considered a prelude to hypogonadism, and treatment with a gonadotropin-releasing hormone agonist may prevent gonadal failure.

Central precocious puberty as a prelude of gonad dysplasia

There is increasing evidence that patients with gonad dysplasia, as characterized by absent or incomplete puberty, can also exhibit central precocious puberty (CPP). Herein, we review the reported cases that manifest with both gonad dysplasia and CPP. Further, we examine the hypothesis that these patients exhibit a normal hypothalamic-pituitary-gonadal axis, hypogonadism, and the presence of residual gonadal function, and that the onset of disease is related to early initiation of the hypothalamic-pituitary-gonadal axis. Thus, we suggest that CPP is a prelude of some partial hypogonadism.

A novel DAX-1 mutation in two male siblings presenting with precocious puberty and late-onset hypogonadotropic hypogonadism

Background The DAX-1 gene is associated with X-linked adrenal hypoplasia congenita (AHC). Our objective was to compare the DAX-1 gene sequence of two male siblings exhibiting different clinical manifestations of AHC. Methods Clinical features were analyzed and laboratory data were collected from both siblings. Genomic DNA was extracted from the peripheral blood leukocytes of the siblings and their parents and the DAX-1 gene exons and intron-flanking regions were amplified by the polymerase chain reaction. The DAX-1 gene sequences were compared following sequencing. Results AHC was diagnosed based on a comprehensive review of the clinical presentation and laboratory tests. Gene analysis revealed a nonsense mutation in DAX-1 gene exon 1 (c.192C>G), resulting in a premature termination codon and a truncated 64-amino acid protein product (p.Tyr64X). Conclusions Our report provides evidence that defined point mutations in the DAX-1 gene do not necessarily translate into the same clinical manifestations of AHC, even in patients with the same pedigree.

NR0B1 Frameshift Mutation in a Boy with Idiopathic Central Precocious Puberty

NR0B1 is the causative gene for X-linked adrenal hypoplasia congenita, characterized by adrenal insufficiency, hypogonadotropic hypogonadism, and infertility. We identified an NR0B1 frameshift mutation in a boy with precocious puberty who had no signs of adrenal insufficiency. Blood examination revealed elevated testosterone levels and gonadotropin hyperresponses to gonadotropin releasing hormone (GnRH) stimulation, together with normal adrenal hormone levels. GnRH analog treatment partially ameliorated his clinical features. Molecular analysis identified a p.Glu3fsAla*16 in NR0B1. These results expand the clinical manifestations of NR0B1 mutations to include central precocious puberty without adrenal insufficiency. NR0B1 mutations likely underlie androgen overproduction via GnRH-dependent and -independent mechanisms.

Adrenal Hypoplasia Congenita: A Rare Cause of Primary Adrenal Insufficiency and Hypogonadotropic Hypogonadism

Primary adrenal insufficiency is defined by the impaired synthesis of adrenocortical hormones due to an intrinsic disease of the adrenal cortex. Determining its etiology is crucial to allow adequate long-term management and genetic counseling. We report the case of a male adolescent that presented in the neonatal period with adrenal crisis and received replacement therapy for primary adrenal insufficiency. During follow-up, adrenal hypoplasia congenita (AHC) was suspected given his persistently raised adrenocorticotropic hormone levels, with markedly low 17-OH progesterone and androstenedione levels. DNA sequence analysis revealed a mutation in NR0B1 gene (c.1292delG), confirming the diagnosis. Delayed puberty and persistent low levels of gonadotropins led to testosterone replacement therapy. X-linked AHC is a rare cause of primary adrenal insufficiency and hypogonadotropic hypogonadism, related to mutations in NR0B1 gene. Despite its rarity, AHC should be considered in patients who present with primary adrenal failure, low levels of 17-OH progesterone and hypogonadotropic hypogonadism.