Rare Causes of Primary Adrenal Insufficiency: Genetic and Clinical Characterization of a Large Nationwide Cohort

CONTEXT

Primary adrenal insufficiency (PAI) is a life-threatening condition that is often due to monogenic causes in children. Although congenital adrenal hyperplasia occurs commonly, several other important molecular causes have been reported, often with overlapping clinical and biochemical features. The relative prevalence of these conditions is not known, but making a specific diagnosis can have important implications for management.

OBJECTIVE

The objective of the study was to investigate the clinical and molecular genetic characteristics of a nationwide cohort of children with PAI of unknown etiology.

DESIGN

A structured questionnaire was used to evaluate clinical, biochemical, and imaging data. Genetic analysis was performed using Haloplex capture and next-generation sequencing. Patients with congenital adrenal hyperplasia, adrenoleukodystrophy, autoimmune adrenal insufficiency, or obvious syndromic PAI were excluded.

SETTING

The study was conducted in 19 tertiary pediatric endocrinology clinics.

PATIENTS

Ninety-five children (48 females, aged 0-18 y, eight familial) with PAI of unknown etiology participated in the study.

RESULTS

A genetic diagnosis was obtained in 77 patients (81%). The range of etiologies was as follows: MC2R (n = 25), NR0B1 (n = 12), STAR (n = 11), CYP11A1 (n = 9), MRAP (n = 9), NNT (n = 7), ABCD1 (n = 2), NR5A1 (n = 1), and AAAS (n = 1). Recurrent mutations occurred in several genes, such as c.560delT in MC2R, p.R451W in CYP11A1, and c.IVS3ds+1delG in MRAP. Several important clinical and molecular insights emerged.

CONCLUSION

This is the largest nationwide study of the molecular genetics of childhood PAI undertaken. Achieving a molecular diagnosis in more than 80% of children has important translational impact for counseling families, presymptomatic diagnosis, personalized treatment (eg, mineralocorticoid replacement), predicting comorbidities (eg, neurological, puberty/fertility), and targeting clinical genetic testing in the future.

Prevalence and long-term follow-up outcomes of testicular adrenal rest tumours in children and adolescent males with congenital adrenal hyperplasia

OBJECTIVE

There are a few studies regarding the prevalence of testicular adrenal rest tumours (TARTs) in boys and adolescent males with congenital adrenal hyperplasia (CAH), and there is little information regarding the treatment outcomes in patients with TARTs. The aim of this study was to determine the long-term treatment outcomes in boys and adolescent males with CAH.

PATIENTS AND METHODS

Sixty boys and adolescent males with CAH, who were between 2 and 18 years of age, were included in the study. Fifty-five patients had 21-hydroxylase deficiency (21-OHD), and five patients had 11-β hydroxylase deficiency (11β-OHD). All patients were screened for TARTs by scrotal ultrasonography (US) performed by an experienced radiologist.

RESULTS

TART prevalence was 18·3% in 2-18 years' of age; eight patients had 21-OHD, and three had 11β-OHD. The youngest patient with TART was 4 years old, whereas eight patients with RTs were at puberty. Only two patients had tight metabolic control: eight patients had stage 2, one had stage 4, and two had stage five rest tumours. In four patients with stage 2 TARTs, tumours disappeared after high-dose steroid treatment and did not recur. Shrinkage of tumour was observed in two patients. Testis-sparing surgery was performed in one patient with stage five tumour. Gonadal functions were normal in patients with partially regressed tumours. Two patients became fathers of healthy male off-springs.

CONCLUSIONS

Detection and treatment for TARTs in children with CAH at younger ages, earlier stages, may prevent infertility in adulthood. Therefore, we recommend that scrotal US screening should be performed in every 1-2 years starting from early childhood.

Assessment of the 21-hydroxylase deficiency and the adrenal functions in young females with Turner syndrome

There are few reports of an association between Turner syndrome (TS) and 21-hydroxylase deficiency. However, this association is more frequent in some populations. The aim of this study was to evaluate the incidence of 21-hydroxylase deficiency in patients with TS in our population. 21-hydroxylase deficiency was evaluated in 44 TS cases with 45X (n=20) and 24 mosaic cases. A standard dose adrenocorticotropic (ACTH) stimulation test (Synacthen, Novartis, Basel, Switzerland) was performed, and 17 hydroxyprogesterone (17OHP), dehydroepiandrosterone sulfate (DHEAS) and cortisol responses were evaluated. Patients with increased 17OHP responses in the stimulation test also underwent 21-hydroxylase gene analysis. The mean age was 14.6 +/- 4 (2.6-22.4); 37 patients were on growth hormone (GH) treatment. Nine patients were at prepubertal stage, whereas 35 were pubertal (24 on gonadal steroids and 11 spontaneously). Six patients were obese. Only one of our patients had a level of 7.5 ng/mL of 17OHP, and there was no mutation found in congenital adrenal hyperplasia (CAH) genetic analysis. In other cases, peak 17OHP levels were < or = 6 ng/mL. The mean peak 17OHP was 2.62 +/- 1.48 (1.19-7.5) ng/mL, the cortisol level was 37.6 +/- 8.43 (23.9-56.2) microg/dL and the DHEAS was 135.2+/- 87.3 (15-413) microg/dL. The increased mean basal and peak cortisol levels (20.5 +/- 10.2 and 37.6 +/- 8.4 microg/dL) were remarkable findings. Whereas basal cortisol was above 20 microg/dL in 38.7% of patients, exaggerated results up to 56.2 microg/dL were obtained in peak cortisol levels. The basal and peak 17OHP cortisol levels were not correlated with the presence of puberty, chromosome structure, gonadal steroid use, obesity or growth hormone use. This trial suggested that 21-hydroxylase deficiency was not common among patients with TS in our population. Adrenal function should be assessed, at least in the presence of clitoral enlargement in patients with TS, particularly if their karyotype does not contain a Y chromosome.

A pediatric Conn syndrome case

Conn syndrome, which is rarely encountered in children, is characterized by increased aldosterone, low renin level, and arterial hypertension. Severe complications, such as impaired vascular smooth muscle function secondary to increased aldosterone, endothelial dysfunction, deterioration of left ventricular functions, acute effects on the cardiovascular system, and proteinuria, may be observed. We present a case of primary aldosteronism in a patient who has been followed up for approximately 2 years. A 15-year-old girl complained of headache lasting for approximately 1.5 years, which was diagnosed as severe hypertension. All of her systemic examinations were normal other than the hypertension. Primary aldosteronism was diagnosed on the basis of hypokalemia and alkalosis accompanied by plasma renin activity of 3.9 ng/mL/h and an aldosterone level of 1007 pg/mL (normal: 40-480). Left adrenalectomy was performed because a 10x12x12 mm adenoma was detected on abdominal magnetic resonance imaging. Although aldosterone levels returned to normal values after the surgery, antihypertensive treatment was continued because of the persistent hypertension. As the 24-h ambulatory blood pressure values of the patient were normal at 10 months after the operation, the treatment was stopped, and she was followed up for 15 months without any treatment. Since then, she has been normotensive.

Mild and severe congenital primary hypothyroidism in two patients by thyrotropin receptor (TSHR) gene mutation

Congenital hypothyroidism (CH) is the most commonly encountered endocrinological birth defect, with an incidence of approximately 1 in 3000-4000 live births. It could be sporadic or familial as well as goitrous or non-goitrous. Inactivating mutations of TSHR , which is one of the genes responsible for non-goitrogenic congenital hypothyroidism, are mostly inherited autosomal recessively and result in a wide clinical spectrum owing to the extent of receptor function loss. Here, we report detailed clinical features of two CH cases with TSHR mutations. The first case was diagnosed before the initiation of the national screening program and had a severe clinical phenotype associated with a homozygous inactivating TSHR mutation (P556R), whereas the second case was diagnosed after the introduction of the national screening program and showed a mild clinical presentation and carried another homozygous missense mutation (P162A) in the TSHR gene. We compared the clinical features of our cases with those of previously reported patients with TSHR mutations to enhance the genotype/phenotype correlations between these mutations and corresponding clinical phenotypes.