Clinical and genetic characteristics of 42 Chinese paediatric patients with X-linked adrenal hypoplasia congenita.

BACKGROUND: X-linked adrenal hypoplasia congenita (AHC) is a rare disorder characterized by primary adrenal insufficiency (PAI) and hypogonadotropic hypogonadism (HH), with limited clinical and genetic characterization. METHODS: The clinical, biochemical, genetic, therapeutic, and follow-up data of 42 patients diagnosed with X-linked AHC were retrospectively analysed. RESULTS: Hyperpigmentation (38/42, 90%), vomiting/diarrhoea (20/42, 48%), failure to thrive (13/42, 31%), and convulsions (7/42, 17%) were the most common symptoms of X-linked AHC at onset. Increased adrenocorticotropic hormone (ACTH) (42/42, 100%) and decreased cortisol (37/42, 88%) were the most common laboratory findings, followed by hyponatremia (32/42, 76%) and hyperkalaemia (29/42, 69%). Thirty-one patients presented with PAI within the first year of life, and 11 presented after three years of age. Three of the thirteen patients over the age of 14 exhibited spontaneous pubertal development, and ten of them experienced delayed puberty due to HH. Six patients receiving human chorionic gonadotropin (hCG) therapy exhibited a slight increase in testicular size and had rising testosterone levels (both P < 0.05). The testicular volumes of the three patients with pulsatile gonadotropin-releasing hormone (GnRH) therapy were larger than those of the six patients undergoing hCG therapy (P < 0.05), and they also exhibited some growth in terms of luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone. Of the 42 patients, three had an Xp21 deletion, and 39 had an isolated DAX1 defect. Most patients (9/10) with entire DAX1 deletion accounting for 23.8% (10/42) of the total variants had early onset age of less than one year. CONCLUSIONS: This study details the clinical features and genetic spectra of X-linked AHC. Patients with X-linked AHC show a bimodal distribution of the age of onset, with approximately 70% presenting within the first year of life. Pulsatile GnRH may be recommended for HH when hCG therapy is not satisfactory, although it is difficult to achieve normal testicular volume. The combination of clinical features and molecular tests provides information for an accurate diagnosis.

Adrenal hypoplasia congenita in identical twins.

We are presenting a monozygotic twin brothers presented at different ages with different presentations. Twin-A presented at age of 18 days with salt losing crisis. Investigations revealed high plasma renin with low-normal aldosterone. Adrenocorticotropic hormone, stimulation test revealed low 17-OH progesterone at 0 and 60 minutes. Adrenocorticotropic hormone level and serum cortisol were normal, which excluded initial impression of congenital adrenal hyperplasia. He was diagnosed to have isolated primary hypoaldosteronism. At age of 18 months, he was noticed to have hyperpigmentation of lips and gum. Adrenal failure was suspected, and hydrocortisone was added. Twin-B presented at 9 years and 6 months of age with adrenal crisis. Both were having unilateral undescended testes. Adrenal hypoplasia congenita (AHC) was suspected after his twin's presentation.  Molecular analysis for gene study for both of them revealed adrenal insufficiency, NR0B1 (DAX1) gene mutation. In conclusion, gene analysis is important for the diagnosis of AHC and for genetic counseling.

[Recurrent anorexia and pigmentation of skin for more than two months in an infant].

A 2-month-old boy presented with adrenal insufficiency, impaired liver function, hypertriglyceridemia, significantly elevated creatine kinase and electrolyte disturbance. Microarray comparative genomic hybridization (aCGH) analysis test showed a pathogenic 8.7 Mb deletion in the short arm of chromosome X (Xp21.3 - p21.1) and confirmed the diagnosis of complex glycerol kinase deficiency (cGKD). He was treated with hydrocortisone, coenzyme Q10 and L-carnitine and was subsequently followed up for 4 years. His serum cortisol levels returned to normal one week later after treatment, but the serum creatine kinase, triglyceride and aminotransferase levels were progressively increased along with mental retardation and decreased muscular strength. cGKD is also named as Xp21 contiguous gene syndrome. The clinical manifestations of this disease include hypertriglyceridemia, congenital adrenal hypoplasia (AHC), Duchenne muscular dystrophy, and mental retardation. This case highlights the necessity to screen the serum triglyceride and creatine kinase levels in infants with suspected adrenal insufficiency.