X-linked congenital adrenal hypoplasia: Report of long clinical follow-up and description of a new complex variant in the NR0B1 gene

Adrenal hypoplasia congenita, attributed to NR0B1 pathogenic variants, accounts for more than 50% of the incidence of primary adrenal insufficiency in children. Although more than 250 different deleterious variations have been described, no genotype-phenotype correlation has been defined to date. We report a case of an adopted boy who reported the onset of an adrenal crisis at 2 weeks of age, requiring replacement therapy with mineralocorticoids and glucocorticoids for 4 months. For 3 years, he did well without treatment. At almost 4 years of age, the disorder was restarted. A long follow-up showed the evolution of hypogonadotropic hypogonadism. Molecular studies on NR0B1 revealed a novel and deleterious deletion-insertion-inversion-deletion complex rearrangement sorted in the 5'-3' direction, which is described as follows: (1) deletion of the intergenic region (between TASL and NR0B1 genes) and 5' region, (2) insertion of a sequence containing 37 bp at the junction of the intergenic region of the TASL gene and a part of exon 1 of the NR0B1 gene, (3) inversion of a part of exon 1, (4) deletion of the final portion of exon 1 and exon 2 and beginning of the 3'UTR region, (5) maintenance of part of the intergenic sequence (between genes MAGEB1 and NR0B1, telomeric sense), (6) large posterior deletion, in the same sense. The path to molecular diagnosis was challenging and involved several molecular biology techniques. Evaluating the breakpoints in our patient, we assumed that it was a nonrecurrent rearrangement that had not yet been described. It may involve a repair mechanism known as nonhomologous end-joining (NHEJ), which joins two ends of DNA in an imprecise manner, generating an "information scar," represented herein by the 37 bp insertion. In addition, the local Xp21 chromosome architecture with sequences capable of modifying the DNA structure could impact the formation of complex rearrangements.

[Acute heart failure in a neonate]

The male patient, one day old, was admitted to the hospital due to hypoglycemia accompanied by apnea appearing six hours after birth. The patient had transient hypoglycemia early after birth, and acute heart failure suddenly occurred on the eighth day after birth. Laboratory tests showed significantly reduced levels of adrenocorticotropic hormone and cortisol, and pituitary magnetic resonance imaging was normal. Genetic testing results showed that the patient had probably pathogenic compound heterozygous mutations of the TBX19 gene (c.917-2A>G+c.608C>T), inherited respectively from the parents. The patient was conclusively diagnosed with congenital isolated adrenocorticotropic hormone deficiency caused by mutation of the TBX19 gene. Upon initiating hydrocortisone replacement therapy, cardiac function rapidly returned to normal. After being discharged, the patient continued with the hydrocortisone replacement therapy. By the 18-month follow-up, the patient was growing and developing well. In neonates, unexplained acute heart failure requires caution for possible endocrine hereditary metabolic diseases, and timely cortisol testing and genetic testing should be conducted.

[A Novel Pathogenic variant in NR0B1 gene associated with Congenital Adrenal Hypoplasia]

X-linked adrenal hypoplasia congenita is a rare cause of primary adrenal insufficiency. Mutations in the NR0B1 gene cause a loss of function in the DAX1 receptor, which activates genes involved in the development and function of the hypothalamic-pituitary-gonadal axis. Objective: To describe a case of adrenal hypoplasia congenita secondary to a mutation in the NR0B1 gene and identified the differential diagnoses of the pediatric patient with adrenal insufficiency and hypogonadotropic hypogonadism. Clinical Case: A 4-year-old male patient with no relevant history and from a rural area was admitted to the emergency room due to a 15-days of emesis, asthenia, adynamia, myalgia, and ataxic gait. On the physical examination, hypotension, hyponatremia, and hyperkalemia, as well as mucosal hyperpigmentation and bilateral cryptorchidism were observed, therefore, adrenal crisis was diagnosed, starting fluid resuscitation with saline solution, hydrocortisone, and fludrocortisone, which stabilized the patient. Adrenal hyperplasia congenita, innate metabolic error, and infectious or autoimmune etiology were ruled out as etiology. A clinical exome test was performed which iden tified the variant c.1275A > T; p.Arg425Ser (Transcript ENST00000378970.5) in the NR0B1 gene consistent with X-linked adrenal hypoplasia congenita. Management of the patient continued with glucocorticoids and mineralocorticoids with favorable clinical course at 7 years of follow-up. Con clusion: A novel pathogenic variant associated with X-linked adrenal hypoplasia is described. Variants in the NR0B1 gene should be a differential diagnosis in a male patient with the association of primary adrenal insufficiency and hypogonadism.

Clinical and Hormonal Profiles Correlate With Molecular Characteristics in Patients With 11β-Hydroxylase Deficiency

BACKGROUND

Given the rarity of 11β-hydroxylase deficiency (11βOHD), there is a paucity of data about the differences in clinical and biochemical characteristics of classic (C-11βOHD) and nonclassic 11βOHD (NC-11βOHD).

OBJECTIVE

To characterize a multicenter pediatric cohort with 11βOHD.

METHOD

The clinical and biochemical characteristics were retrospectively retrieved. CYP11B1 gene sequencing was performed. Seventeen plasma steroids were quantified by liquid chromatography-mass spectrometry and compared to that of controls.

RESULTS

102 patients (C-11βOHD, n = 92; NC-11βOHD, n = 10) from 76 families (46,XX; n = 53) had biallelic CYP11B1 mutations (novel 9 out of 30). Five 46,XX patients (10%) were raised as males. Nineteen patients (19%) had initially been misdiagnosed with 21-hydroxylase deficiency. Female adult height was 152 cm [-1.85 SD score (SDS)] and male 160.4 cm (-2.56 SDS).None of the NC-11βOHD girls had ambiguous genitalia (C-11βOHD 100%), and none of the NC-11βOHD patients were hypertensive (C-11βOHD 50%). Compared to NC-11βOHD, C-11βOHD patients were diagnosed earlier (1.33 vs 6.9 years; P < 0.0001), had higher bone age-to-chronological age (P = 0.04) and lower adult height (-2.46 vs -1.32 SDS; P = 0.05). The concentrations of 11-oxygenated androgens and 21-deoxycortisol were low in all patients. The baseline ACTH and stimulated cortisol were normal in NC-11βOHD. Baseline cortisol; cortisone; 11-deoxycortisol; 11-deoxycorticosterone and corticosterone concentrations; and 11-deoxycortisol/cortisol, 11-deoxycorticosterone/cortisol, and androstenedione/cortisol ratios were higher in C-11βOHD than NC-11βOHD patients (P < 0.05). The 11-deoxycortisol/cortisol ratio >2.2, <1.5, and <0.1 had 100% specificity to segregate C-11βOHD, NC-11βOHD, and control groups.

CONCLUSION

NC-11βOHD can escape from clinical attention due to relatively mild clinical presentation. However, steroid profiles enable the diagnosis, differential diagnosis, and subtyping of 11βOHD.

Primary Adrenal Insufficiency in Childhood: Data From a Large Nationwide Cohort

CONTEXT

Primary adrenal insufficiency (PAI) is a rare and potentially life-threatening condition that is poorly characterized in children.

OBJECTIVE

To describe causes, presentation, auxological outcome, frequency of adrenal crisis and mortality of a large cohort of children with PAI.

PATIENTS AND METHODS

Data from 803 patients from 8 centers of Pediatric Endocrinology were retrospectively collected.

RESULTS

The following etiologies were reported: 85% (n = 682) congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21-OHD); 3.1% (n = 25) X-linked adrenoleukodystrophy; 3.1% (n = 25) autoimmune polyglandular syndrome type 1; 2.5% (n = 20) autoimmune adrenal insufficiency; 2% (n = 16) adrenal hypoplasia congenital; 1.2% (n = 10) non-21-OHD CAH; 1% (n = 8) rare syndromes; 0.6% (n = 5) familial glucocorticoid deficiency; 0.4% (n = 3) acquired adrenal insufficiency; 9 patients (1%) did not receive diagnosis. Since 21-OHD CAH has been extensively characterized, it was not further reviewed. In 121 patients with a diagnosis other than 21-OHD CAH, the most frequent symptoms at diagnosis were fatigue (67%), hyperpigmentation (50.4%), dehydration (33%), and hypotension (31%). Elevated adrenocorticotropic hormone (96.4%) was the most common laboratory finding followed by hyponatremia (55%), hyperkalemia (32.7%), and hypoglycemia (33.7%). The median age at presentation was 6.5 ± 5.1 years (0.1-17.8 years) and the mean duration of symptoms before diagnosis was 5.6 ± 11.6 months (0-56 months) depending on etiology. Rate of adrenal crisis was 2.7 per 100 patient-years. Three patients died from the underlying disease. Adult height, evaluated in 70 patients, was -0.70 ± 1.20 standard deviation score.

CONCLUSIONS

We characterized one of the largest cohorts of children with PAI aiming to improve the knowledge on diagnosis of this rare condition.

A rare cause of neonatal hypoglycemia in two siblings: TBX19 gene mutation

Congenital isolated adrenocorticotropic hormone (ACTH) deficiency (IAD) is a rarely seen disease characterized by low serum ACTH and cortisol levels accompanied by normal levels of the other anterior pituitary hormones. In these patients, severe hypoglycemia, convulsions, and prolonged cholestatic jaundice are expected findings in the neonatal period. In this paper, we present two siblings with TBX19 gene mutation. The first case was investigated at the age of 2 months for severe hypoglycemia, recurrent convulsions, and prolonged cholestatic jaundice persisting since the neonatal period. The second sibling presented with hypoglycemia in the neonatal period. In both cases, baseline cortisol and ACTH levels were low and cortisol response to the low-dose ACTH test was inadequate, while all other anterior pituitary hormones were normal. Thus, IAD was suspected. Genetic analysis of the TBX19 gene was performed. Both cases were homozygous for c.856 C>T (p.R286*), and hydrocortisone treatment was initiated. The first patient did not attend the clinic regularly. On attendance at another hospital, hydrocortisone treatment was discontinued and antiepileptic treatment was initiated because of suspected epilepsy. This led to developmental delay, measured with the Denver Developmental Screening Test II (DDST-II), because of cessation of the hydrocortisone therapy. The second sibling had normal development, as measured with the DDST. In conclusion, TBX19 gene analysis must be performed if adrenal insufficiency is associated with isolated ACTH deficiency. Delay in diagnosis may lead to inappropriate diagnoses, such as epilepsy, and thus inappropriate therapy, which may result in neonatal mortality.

Somatic mutations and progressive monosomy modify SAMD9-related phenotypes in humans

It is well established that somatic genomic changes can influence phenotypes in cancer, but the role of adaptive changes in developmental disorders is less well understood. Here we have used next-generation sequencing approaches to identify de novo heterozygous mutations in sterile α motif domain-containing protein 9 (SAMD9, located on chromosome 7q21.2) in 8 children with a multisystem disorder termed MIRAGE syndrome that is characterized by intrauterine growth restriction (IUGR) with gonadal, adrenal, and bone marrow failure, predisposition to infections, and high mortality. These mutations result in gain of function of the growth repressor product SAMD9. Progressive loss of mutated SAMD9 through the development of monosomy 7 (-7), deletions of 7q (7q-), and secondary somatic loss-of-function (nonsense and frameshift) mutations in SAMD9 rescued the growth-restricting effects of mutant SAMD9 proteins in bone marrow and was associated with increased length of survival. However, 2 patients with -7 and 7q- developed myelodysplastic syndrome, most likely due to haploinsufficiency of related 7q21.2 genes. Taken together, these findings provide strong evidence that progressive somatic changes can occur in specific tissues and can subsequently modify disease phenotype and influence survival. Such tissue-specific adaptability may be a more common mechanism modifying the expression of human genetic conditions than is currently recognized.

Sphingosine-1-phosphate lyase mutations cause primary adrenal insufficiency and steroid-resistant nephrotic syndrome

Primary adrenal insufficiency is life threatening and can present alone or in combination with other comorbidities. Here, we have described a primary adrenal insufficiency syndrome and steroid-resistant nephrotic syndrome caused by loss-of-function mutations in sphingosine-1-phosphate lyase (SGPL1). SGPL1 executes the final decisive step of the sphingolipid breakdown pathway, mediating the irreversible cleavage of the lipid-signaling molecule sphingosine-1-phosphate (S1P). Mutations in other upstream components of the pathway lead to harmful accumulation of lysosomal sphingolipid species, which are associated with a series of conditions known as the sphingolipidoses. In this work, we have identified 4 different homozygous mutations, c.665G>A (p.R222Q), c.1633_1635delTTC (p.F545del), c.261+1G>A (p.S65Rfs*6), and c.7dupA (p.S3Kfs*11), in 5 families with the condition. In total, 8 patients were investigated, some of whom also manifested other features, including ichthyosis, primary hypothyroidism, neurological symptoms, and cryptorchidism. Sgpl1-/- mice recapitulated the main characteristics of the human disease with abnormal adrenal and renal morphology. Sgpl1-/- mice displayed disrupted adrenocortical zonation and defective expression of steroidogenic enzymes as well as renal histology in keeping with a glomerular phenotype. In summary, we have identified SGPL1 mutations in humans that perhaps represent a distinct multisystemic disorder of sphingolipid metabolism.

NNT mutations: a cause of primary adrenal insufficiency, oxidative stress and extra-adrenal defects

OBJECTIVE

Nicotinamide nucleotide transhydrogenase (NNT), one of the several genes recently discovered in familial glucocorticoid deficiencies (FGD), is involved in reactive oxygen species detoxification, suggesting that extra-adrenal manifestations may occur, due to the sensitivity to oxidative stress of other organs rich in mitochondria. Here, we sought to identify NNT mutations in a large cohort of patients with primary congenital adrenal insufficiency without molecular etiology and evaluate the degree of adrenal insufficiency and onset of extra-adrenal damages.

METHODS

Sanger or massive parallel sequencing of NNT and patient monitoring.

RESULTS

Homozygous or compound heterozygous NNT mutations occurred frequently (26%, 13 unrelated families, 18 patients) in our cohort. Seven new mutations were identified: p.Met337Val, p.Ala863Glu, c.3G>A (p.Met1?), p.Arg129*, p.Arg379*, p.Val665Profs*29 and p.Ala704Serfs*19. The most frequent mutation, p.Arg129*, was found recurrently in patients from Algeria. Most patients were diagnosed belatedly (8-18 months) after presenting severe hypoglycemia; others experiencing stress conditions were diagnosed earlier. Five patients also had mineralocorticoid deficiency at onset. One patient had congenital hypothyroidism and two cryptorchidism. In follow-up, we noticed gonadotropic and genitalia impairments (precocious puberty, testicular inclusions, interstitial Leydig cell adenoma, azoospermia), hypothyroidism and hypertrophic cardiomyopathy. Intrafamilial phenotype heterogeneity was also observed.

CONCLUSIONS

NNT should be sequenced, not only in FGD, but also in all primary adrenal insufficiencies for which the most frequent etiologies have been ruled out. As NNT is involved in oxidative stress, careful follow-up is needed to evaluate mineralocorticoid biosynthesis extent, and gonadal, heart and thyroid function.

First case report of rare congenital adrenal insufficiency caused by mutations in the CYP11A1 gene in the Czech Republic

We characterized a case of congenital adrenal insufficiency caused by cholesterol side-chain cleavage enzyme (P450scc) deficiency. The patient presented after birth with cardiopulmonary instability, hyponatremia, hyperkalemia, hypoglycemia and metabolic acidosis. We confirmed primary adrenal insufficiency. There were no signs of the external genitalia virilism. The replacement therapy with glucocorticoids and mineralocorticoids led to normal laboratory results. At the age of 12 years, we confirmed hypergonadotropic hypogonadism, which revealed disorder of steroidogenesis in the adrenal glands and in the gonads. The enzymatic block was found at the beginning of steroidogenesis. The mutation was confirmed in the CYP11A1 gene. The patient is compound heterozygote for the novel CYP11A1 missense mutation c.412G>A (p.Gly138Arg) in exon 2 and frameshift mutation c.508_509delCT (p.Leu170Valfs*30) in exon 3. The CYP11A1: c.412G>A (p.Gly138Arg) was predicted as pathogenic by in silico analysis. So far, only 19 patients with CYP11A1 mutations causing P450scc deficiency have been reported worldwide. There are no related reports in the Czech Republic.

Current and novel approaches to children and young people with congenital adrenal hyperplasia and adrenal insufficiency

Congenital adrenal hyperplasia (CAH) represents a group of autosomal recessive conditions leading to glucocorticoid deficiency. CAH is the most common cause of adrenal insufficiency (AI) in the paediatric population. The majority of the other forms of primary and secondary adrenal insufficiency are rare conditions. It is critical to establish the underlying aetiology of each specific condition as a wide range of additional health problems specific to the underlying disorder can be found. Following the introduction of life-saving glucocorticoid replacement sixty years ago, steroid hormone replacement regimes have been refined leading to significant reductions in glucocorticoid doses over the last two decades. These adjustments are made with the aim both of improving the current management of children and young persons and of reducing future health problems in adult life. However despite optimisation of existing glucocorticoid replacement regimens fail to mimic the physiologic circadian rhythm of glucocorticoid secretion, current efforts therefore focus on optimising replacement strategies. In addition, in recent years novel experimental therapies have been developed which target adrenal sex steroid synthesis in patients with CAH aiming to reduce co-morbidities associated with sex steroid excess. These developments will hopefully improve the health status and long-term outcomes in patients with congenital adrenal hyperplasia and adrenal insufficiency.

Development and testing in healthy adults of oral hydrocortisone granules with taste masking for the treatment of neonates and infants with adrenal insufficiency

BACKGROUND

Treatment of neonates and infants with adrenal insufficiency is unsatisfactory because unlicensed hydrocortisone formulations are used.

OBJECTIVES

The objectives were to survey current hydrocortisone prescribing practice and develop a novel hydrocortisone formulation, Infacort.

METHODS

The use of hydrocortisone by European pediatric endocrinologists was surveyed. Based on this, an oral hydrocortisone granule formulation, Infacort, with taste masking was developed and evaluated in vitro and then in vivo in a phase I pharmacokinetic study.

RESULTS

The survey showed that pediatricians use a variety of unlicensed compounded adult medications at doses of between 0.5 and 5 mg. Infacort was formulated with a taste-masking layer stable for at least 5 minutes in aqueous media and was produced in unit doses of 0.5, 1, 2, and 5 mg. Infacort 10 mg is the bioequivalent of a 10-mg hydrocortisone tablet (mean area under the curve from zero to infinity [AUC(0-inf)] ratio, 101%; 90% confidence interval, 96-107%). Mean cortisol maximum concentration (C(max)) and AUC(0-inf) values after administration of Infacort were linear with dose and dose proportional when adjusted for saturable plasma protein binding. Subjects rated Infacort as "not good or bad" for smell (86%), feel in the mouth (71%), and taste (79%). No serious adverse events were reported.

CONCLUSIONS

This phase 1 study demonstrates that Infacort is safe, well tolerated, of neutral taste, bioequivalent to hydrocortisone licensed for adults, and shows dose proportionality with respect to cortisol exposure. Infacort is expected to facilitate optimization of hydrocortisone dosing in neonates and children with adrenal insufficiency; however, clinical studies will be required to demonstrate efficacy in this patient age group.

Clinical features of congenital adrenal insufficiency including growth patterns and significance of ACTH stimulation test

Congenital adrenal insufficiency is caused by specific genetic mutations. Early suspicion and definite diagnosis are crucial because the disease can precipitate a life-threatening hypovolemic shock without prompt treatment. This study was designed to understand the clinical manifestations including growth patterns and to find the usefulness of ACTH stimulation test. Sixteen patients with confirmed genotyping were subdivided into three groups according to the genetic study results: congenital adrenal hyperplasia due to 21-hydroxylase deficiency (CAH, n=11), congenital lipoid adrenal hyperplasia (n=3) and X-linked adrenal hypoplasia congenita (n=2). Bone age advancement was prominent in patients with CAH especially after 60 months of chronologic age (n=6, 67%). They were diagnosed in older ages in group with bone age advancement (P<0.05). Comorbid conditions such as obesity, mental retardation, and central precocious puberty were also prominent in this group. In conclusion, this study showed the importance of understanding the clinical symptoms as well as genetic analysis for early diagnosis and management of congenital adrenal insufficiency. ACTH stimulation test played an important role to support the diagnosis and serum 17-hydroxyprogesterone levels were significantly elevated in all of the CAH patients. The test will be important for monitoring growth and puberty during follow up of patients with congenital adrenal insufficiency.

Nocturnal hypoglycaemia in ACTH and GH deficient children: role of continuous glucose monitoring

OBJECTIVES

To evaluate the usefulness of continuous glucose monitoring (CGM) to identify nocturnal hypoglycaemia in children affected by combined ACTH and GH deficiency and to optimize the hydrocortisone replacement therapy in these patients.

STUDY DESIGN

Eleven patients with ACTH and GH deficiency (five boys and six girls, age 1·6-16·8 years) underwent CGM for 36 h, including two nights. At least two consecutive glucose levels <2·78 mm were considered hypoglycaemic episodes. The differences in age and doses of hydrocortisone and recombinant human growth hormone (rhGH) between children with and without hypoglycaemia were analysed. The percentage of the glucose values <3·33 mm and the mean glucose levels were also evaluated.

RESULTS

Continuous glucose monitoring demonstrated nocturnal hypoglycaemia lasting from 30 to 155 min (1·5% of the total monitoring time) in three cases (27%). No statistically significant differences in age and rhGH dose were observed between children with or without hypoglycaemia. Conversely, the difference in the hydrocortisone doses between the patients with and without hypoglycaemia resulted statistically significant (5·9 vs 8·5 mg/m²/day; P = 0·04). Eight patients presented glucose values less than 3·33 mm during 5% of the total monitoring time. Hydrocortisone dose showed significant positive linear relation with mean glucose level (r = 0·79, P = 0·0035) and inverse relation with time lags of glucose levels under 3·33 mm (r = -0·65, P = 0·03).

CONCLUSIONS

Our study shows that CGM may represent a valuable tool to detect nocturnal asymptomatic hypoglycaemic episodes and optimize the hydrocortisone therapeutic regimen in children with ACTH and GH deficiency.

Long-term clinical data and molecular defects in the STAR gene in five Greek patients

CONTEXT

Steroidogenic acute regulatory (STAR) gene mutations lead to adrenal and gonadal failure. Interesting, though as yet unexplained, features are the formation of ovarian cysts and the potential presence of CNS findings.

OBJECTIVE

To report biochemical, genetic, and long-term clinical data in five Greek patients from four different families with STAR gene defects (three 46,XX and two 46,XY).

METHODS AND RESULTS

All patients presented in early infancy with adrenal insufficiency. The STAR gene mutation c.834del11bp, detected in three of our patients, completely alters the carboxyl end of the STAR protein and has not thus far been described in other population groups. These three patients belong to three separate families, possibly genetically related, as they live in different villages located in a small region of a Greek island. However, their interrelationship has not been proven. A second mutation, p.W250X, detected in our fourth family, was previously described only in two Serbian patients. Ovarian cysts were detected ultrasonographically in our 46,XX patients and seemed to respond to a low dose of a contraceptive. The histology of an excised ovarian cyst was diagnosed as a corpus luteum (CL) cyst. In two out of the four patients who had undergone brain magnetic resonance imaging, asymptomatic Chiari-1 malformation was observed.

CONCLUSIONS

The occurrence of STAR gene mutation c.834del11bp in three families living in a restricted geographic region could indicate either a founder effect or simply reflect a spread of this defect in a highly related population. The ovarian histological findings suggest that ovarian cysts detected ultrasonographically in 46,XX individuals with STAR gene defects may be CL cysts. The Chiari-1 malformation in two of our patients may be part of the STAR gene mutation phenotype. Nevertheless, more data are needed to confirm or disprove the existence of specific CNS pathology in patients with STAR gene mutations.

Cushing disease with pregnancy

Pregnancy occurs rarely in patients with Cushing syndrome (CS) due to hypercortisolism. So far, about 150 cases of CS in pregnancy have been reported in the literature. We describe a 22-year-old female who presented in pregnancy with clinical features of CS. She delivered at 34 weeks of gestation and baby had transient adrenal insufficiency in the neonatal period. Mother underwent transsphenoidal surgery 1 year postpartum and on follow up she is under remission. Neonatal hypoadrenalism should be anticipated in maternal CS.

Clinical, biological and genetic analysis of 8 cases of congenital isolated adrenocorticotrophic hormone (ACTH) deficiency

Background

Congenital isolated adrenocorticotrophic hormone (ACTH) deficiency may be rare, but it could be an underestimated cause of neonatal death. Our objective was to shorten the time between first symptoms and diagnosis.

Methods

This single-centre retrospective case-cohort study was carried out on eight consecutive patients.

Results

Two had the neonatal form and 6 the late onset form. Six were admitted to an intensive care unit at least once for seizures with hypoglycemia, major hypothermia, fever, and/or collapsus. The 2 neonatal cases presented with hypoglycemia and in a state of “apparent death” at birth or hypothermia (29°C) at 6 days. All 6 late onset cases had also been admitted to an emergency department 1–3 times, but had left hospital incorrectly diagnosed. Their first symptoms were noted at 3–12.3 years, and they were diagnosed at 3.3–14.4 years. All had hypoglycemia, and 4 had had seizures. The presenting symptoms were vomiting and/or abdominal pain, asthenia, irritability, difficulty with physical activities, and anorexia. The school performance of 4 deteriorated. Two underwent psychotherapy and treatment for depression, which was stopped when Hydrocortisone® replacement therapy began.

The plasma concentrations in spontaneous hypoglycemia were: ACTH<5 to 17.1 pg/mL, with concomitant cortisol <3.5 to 37 ng/mL. The plasma dehydroepiandrosterone sulfate (DHAS) concentrations were low in the 7 evaluated. The coding sequence of TPIT was normal in all.

Conclusion

Several unexplained symptoms in a child, mainly gastro-intestinal symptoms and seizures due to hypoglycemia, may indicate ACTH deficiency. A low or normal basal plasma ACTH despite concomitant low cortisol at 8 a.m. and/or in spontaneous hypoglycemia, associated with low DHAS, in a patient not given corticosteroids is highly suggestive of ACTH deficiency. The isolated character of ACTH deficiency must be confirmed by determining the other hypothalamic-pituitary functions, and Hydrocortisone® replacement therapy initiated in emergency.

Seven novel DAX1 mutations with loss of function identified in Chinese patients with congenital adrenal hypoplasia

CONTEXT

DAX1 (for dosage-sensitive sex reversal, adrenal hypoplasia congenital critical region on the X chromosome, gene 1; also called NROB1) mutations are responsible for adrenal failure and hypogonadotropic hypogonadism in patients with adrenal hypoplasia congenita (AHC), through a loss of trans-repression of SF-1 (for steroidogenic factor-1)-mediated StAR (for steroidogenic acute regulatory protein) and LHbeta transcriptional activities and a reduction of GnRH expression. The correlation of clinical features with genetic and functional alterations of the gene was investigated in detail in AHC patients.

OBJECTIVE

The present study aimed at identifying DAX1 mutations in Chinese AHC patients and investigating the functional defects of detected novel mutations.

PATIENTS AND METHODS

Nine patients with AHC were recruited from eight families. DAX1 mutations were screened, and the transcriptional activities of the identified mutations were assessed in vitro.

RESULTS

DAX1 mutations were detected in all nine patients enrolled in the study, with eight different mutations. Among the latter, seven are novel mutations, including two missense (L262P and C368F), one nonsense (Q222X), and four frame-shift (637delC, 652_653delAC, 973delC, and 774_775insCC) mutations. The functional studies showed that the mutant DAX1 was impaired by nuclear localization, loss of trans-repression of StAR and LHbeta transcriptional activities, and reduction of GnRH expression.

CONCLUSION

These findings provide insight into the molecular events by which DAX1 mutations influence the hypothalamus-pituitary-gonadal and hypothalamus-pituitary-adrenal axis and lead to AHC and hypogonadotropic hypogonadism.

Growth hormone deficiency due to traumatic brain injury in a patient with X-linked congenital adrenal hypoplasia

X-linked adrenal hypoplasia congenita (AHC) is characterized by primary adrenal insufficiency and is frequently associated with hypogonadotropic hypogonadism (HH). The production of other pituitary hormones (adrenocorticotropic hormone [ACTH], growth hormone [GH], thyroid-stimulating hormone [TSH], and prolactin [PRL]) is usually normal. Mutations of the DAX-1 gene have been reported in patients with AHC and HH. We present a 13-year-old male patient with AHC caused by a nonsense mutation in the DAX-1 gene who developed GH deficiency following head trauma. He showed signs of adrenal insufficiency at the age of 23 months, and glucocorticoid and mineralocorticoid treatment was started. His parents reported head trauma due to a traffic accident at the age of 21 months. Adrenal computed tomography revealed hypoplasia of the left and agenesis of the right adrenal gland. Decreased growth rate was noted at the age of 12.5 years while receiving hydrocortisone 15 mg/m2/day. His height was 139.9 cm (-1.46 SD), body weight was 54.9 kg, pubic hair was Tanner stage 1, and testis size was 3 ml. His bone age was 7 years. His gonadotropin (follicle-stimulating hormone [FSH], luteinizing hormone [LH]) and testosterone levels were prepubertal. The evaluation of GH/insulin-like growth factor-1 (IGF-1) secretion at the age of 13 years revealed GH deficiency. Pituitary magnetic resonance imaging demonstrated a hypoplastic hypophysis (< 2.5 mm) and a normal infundibulum. GH treatment (0.73 IU/kg/week) was started. This paper reports a patient with genetically confirmed AHC demonstrating GH deficiency possibly due to a previous head trauma. Complete pituitary evaluation should be performed in any child who has survived severe traumatic brain injury.

Clinical and genetic heterogeneity of congenital adrenal hypoplasia due to NR0B1 gene mutations

INTRODUCTION

X-linked adrenal hypoplasia congenita (AHC) is a rare disorder caused by mutations or complete deletion of the NR0B1 gene that encodes the DAX-1 protein, an orphan member of the nuclear receptor superfamily. AHC is characterized by adrenal insufficiency in infancy and early childhood. Later, hypogonadotropic hypogonadism (HH) manifests as pubertal failure.

PATIENTS AND METHODS

We evaluated the clinical, endocrine and molecular characteristics of 12 AHC patients from 5 families diagnosed between 1984 and 2007 in Israel.

RESULTS

Most of the boys (10/12) presented with signs of adrenal insufficiency such as salt wasting and failure to thrive during the neonatal period. Aldosterone deficiency usually preceded cortisol deficiency requiring early mineralocorticoid therapy. Serum cortisol levels in the first weeks of life varied from very low to high levels (<2.76 to >1776 nmol/l). Five boys showed signs of precocious sexual development during infancy and childhood, including enlargement of the penis and testes. In four patients the initial diagnoses were erroneous. Molecular analysis of the NR0B1 gene identified point mutations in six patients including a novel splice site mutation in one patient and his family (IVS1-1G-->C). Contiguous gene deletion was found in six patients from two families who manifested impaired mental development.

CONCLUSIONS

In X-linked AHC caused by different molecular defects in NR0B1 gene, the clinical spectrum of the disease is quite variable and precocious sexual development is a prominent feature. Genetic testing is indicated in boys presenting with salt-wasting with or without cortisol deficiency if congenital adrenal hyperplasia has been ruled out.

A novel mutation in DAX1 (NR0B1) causing X-linked adrenal hypoplasia congenita: clinical, hormonal and genetic analysis

The association of primary adrenal insufficiency and hypogonadotropic hypogonadism is extremely infrequent in daily clinical practice. Differential diagnosis includes X-linked adrenal hypoplasia congenita, a genetic disease characterized by an alteration in the formation of the adrenal glands and the hypothalamus-pituitary-gonadal axis. The gene responsible is DAX1 (NR0B1). The most common form of clinical presentation is neonatal primary adrenal insufficiency and complete hypogonadotropic hypogonadism. Members of a single family often present the same clinical form, although there may be relatives affected with different clinical symptoms. The aim of this study is to characterize clinically and genetically a family affected by different forms of hypogonadotropic hypogonadism and/or primary adrenal insufficiency. We describe a family with three members affected, two adults and a neonate. The way of presentation of the adults was neonatal primary adrenal insufficiency and hypogonadotropic hypogonadism (one complete and another presenting as interrupted puberty). The genetic study revealed a new mutation in DAX1, p.Q76X gene (c.C226T), resulting in a truncated protein of 76 amino acids, the same in all three affected male patients and in the asymptomatic women of the family. These cases further expand the number of DAX1 mutations reported, as well as the description of infrequent forms of presentation of this disease as interrupted puberty.

A novel missense mutation in DAX-1 with an unusual presentation of X-linked adrenal hypoplasia congenita

A male presented at age 2.2 years with a 6-week history of intermittent vomiting and hyperpigmentation. Investigations showed salt wasting with hyperkalaemia, a grossly impaired cortisol response to ACTH stimulation, elevated renin and ACTH. Family history revealed that two maternal uncles had died soon after birth. A third uncle failed to thrive during infancy but improved with a course of cortisone, then being untreated until further investigation revealed adrenal insufficiency. A fourth uncle died aged 10 days, with urinary salt loss and hypoplastic adrenal glands at postmortem. Molecular studies on the proband, his mother, maternal grandmother, and surviving uncle showed a novel C to G substitution at nucleotide position 794 (missense mutation T265R) in the DAX1 (NR0B1) gene. The proband has responded well to steroid replacement but has proved sensitive to 9alpha-fludrocortisone treatment, developing hypertension on a dose of 133 microg/m(2)/day. At 8.8 years he was noted to have testicular volumes of 4 ml, despite no other evidence of secondary sexual development and prepubertal gonadotrophin levels. Novel features of this family include a novel DAX1 mutation, marked variability in age of presentation, hypertension on 'standard' doses of 9alpha-fludrocortisone and mild testicular enlargement.

Two siblings with 46,XY DSD, congenital adrenal hypoplasia, aniridia, craniofacial, and skeletal abnormalities and intrauterine growth retardation: A new syndrome?

We report on two siblings with an unusual constellation of congenital anomalies comprising 46,XY disorder of sex development (DSD), congenital adrenal hypoplasia, aniridia, dysmorphic facial features, intrauterine growth retardation, and minor skeletal abnormalities. This combination of abnormalities is yet to be recognized in the medical literature. As such, we propose that our patients represent either a new dysmorphic syndrome or a thus far unrecognized variation of a known syndrome, such as IMAGe syndrome. The sibling recurrence suggests autosomal recessive or X-linked patterns of inheritance.

Partial defects in transcriptional activity of two novel DAX-1 mutations in childhood-onset adrenal hypoplasia congenita

OBJECTIVE

Mutations in DAX-1, an X-linked gene encoding an orphan nuclear receptor, have been associated with adrenal hypoplasia congenita and hypogonadotropic hypogonadism. Here we describe two novel DAX-1 mutations, Y214X and I361T, associated with childhood-onset primary adrenal failure. We aimed at analysing their effects on protein localization, transcriptional activity and propose a structural-function relationship.

DESIGN

We have directly sequenced the DAX-1 gene from PCR-amplified DNA. The effect of the mutations on protein localization was assessed by immunocytochemistry in transfected cells. The impact of mutations on transcriptional activity was determined by transfection using a StAR promoter-luciferase reporter system.

RESULTS

The mutation Y214X produces a protein lacking the C-terminal half of DAX-1. The other one, I361T, affects a highly conserved amino acid within the putative ligand-binding domain. The mutant Y214X displayed a wild-type subcellular localization while I361T was partially retained in the cytoplasm. Both mutants retained subtantial transcriptional repressive activity, compared to mutants producing early onset adrenal failure. Interestingly, I361T displayed similar in vitro transcriptional repressive activity to the mutant I439S previously described in a case of late-onset AHC. This shows that molecular alterations of DAX-1 leading to similar in vitro activities may result in very different ages of onset of adrenal failure, which suggests that additional genetic and epigenetic factors are important in determining the clinical course of AHC.

CONCLUSIONS

Our results help the understanding of structure-function relationships in the DAX-1 molecule, suggesting that the N-terminal domain is relatively autonomous and add credence to presumed molecular interactions within ligand binding domain of the protein.

Two sisters with IMAGe syndrome: cytomegalic adrenal histopathology, support for autosomal recessive inheritance and literature review

Adrenal hypoplasia congenita (AHC) is a rare condition and causes primary adrenal insufficiency. X-linked (OMIM 300200) and autosomal recessive (OMIM 240200) forms are recognized. Recently, an association between Intrauterine growth restriction, Metaphyseal dysplasia, Adrenal hypoplasia congenita, and Genital abnormalities (IMAGe syndrome; OMIM 300290) has been described. We present the clinical features of two sisters with intrauterine growth restriction, AHC, and dysmorphic features. Interesting histopathologic findings of one sister are also presented. We suggest that IMAGe syndrome is the most plausible diagnosis and that autosomal recessive inheritance is likely. We analyzed genes that were postulated candidates for IMAGe syndrome (SF1, DAX-1, and STAR), and no mutations were found. Other cases of IMAGe syndrome are reviewed.

Importance of genetic diagnosis of DAX-1 deficiency: example from a large, multigenerational family

BACKGROUND

Inactivating mutations of DAX-1 give rise to the X-linked form of adrenal hypoplasia congenita (AHC). Affected fetuses are at risk of early postnatal Addisonian crisis, but the variable phenotypic expression of DAX-1 insufficiency renders this diagnosis challenging.

METHODS

We describe the familial transmission of AHC over several generations. The proband was diagnosed with adrenal insufficiency at age 3.5 years: molecular analysis revealed a novel, 373-bp deletion including the second exon of DAX-1. Given the familial history of several unexplained deaths in male infants related to the proband via his maternal great-grandmother, we hypothesized that all these boys had been affected with AHC. Another female member of the family being pregnant with a male fetus at the time, we performed DAX-1 analysis on the mother and the newborn. The mother was heterozygous for the deletion, and the newborn hemizygous: he presented an adrenal crisis at 10 days of life, and is now doing well on hormone replacement therapy.

CONCLUSION

The unfortunate deaths of male infants at each generation of this family underlie the importance of early and precise diagnosis of this rare condition, stressing the value of genetic diagnosis in six potential female carriers of this family entering their reproductive years.

Forced mouth opening reaction: a primitive reflex released from cortical inhibition

We report the case of a 6-year-old girl with congenital adrenal hyperplasia, who showed 'forced mouth opening reaction' during the course of acute encephalopathy due to adrenal crisis. When an object was moved towards her mouth, or when the corner of her mouth was stroked with a tongue depressor, she would immediately open her mouth fully and hold it open. This reaction appeared transiently during the course of her illness in association with other frontal release signs including the rooting, groping and palmomental reflexes. Magnetic resonance imaging showed bilateral widespread lesions involving the gray and white matters in the frontal lobes, and less severe lesions in the temporal and parietal areas. We propose that this unique reaction is a sign of a release phenomenon, and represents the emergence of primitive reflexes in the absence of cortical inhibition in some types of encephalopathies.

IMAGe association and congenital adrenal hypoplasia: no disease-causing mutations found in the ACD gene

The spontaneous mouse mutant adrenocortical dysplasia (acd) is characterized by defects in the adrenals, kidneys, and gonads of adult mutant mice and by caudal dysgenesis and vertebral segmentation defects in acd embryos. This association of defects mirrors those identified in patients with known or suspected abnormalities in adrenocortical development, including adrenal hypoplasia congenita and IMAGe association. The identification of the Acd gene in mice has prompted the study of its human homolog ACD, which has recently been shown to be a regulator of telomere length. Sequencing of ACD in 15 patients revealed no coding mutations, but three novel SNPs were identified.

Low estriol levels in the maternal triple-marker screen as a predictor of isolated adrenocorticotropic hormone deficiency caused by a new mutation in the TPIT gene

Isolated adrenocorticotropic hormone (ACTH) deficiency (IAD) is a rare cause of adrenocortical insufficiency, especially in children, and may be an underestimated cause of neonatal death. Early postnatal diagnosis may prevent hypoglycemic seizures, Addisonian crises, and death. There are also occasional reports of prenatal diagnosis of IAD by findings on the maternal triple-marker screen (TMST), a combined serum analyte test that measures levels of alpha-fetoprotein, human chorionic gonadotropin, and unconjugated estriol for the detection of Down syndrome and open neural-tube defects. An isolated low estriol level is usually correlated with compromised uteroplacental perfusion and frequently associated with fetal death. A low estriol level in the context of normal fetal sonography and growth, after exclusion of placental sulfatase deficiency and Smith-Lemli-Opitz syndrome, should raise the suspicion of deficient fetal steroidogenesis, which leads to decreased production of adrenal dehydroepiandrosterone sulfate. We describe 2 brothers with adrenal insufficiency resulting from IAD. The parents are first cousins whose first son is healthy. During the pregnancy of the second son, who died at the age of 7 weeks as a result of presumed cardiomyopathy, a low estriol level on the TMST was ignored because of a normal fetal ultrasound. In the third pregnancy, a low level was found again, and the mother was referred to our tertiary center. Ultrasonography revealed no abnormalities, and karyotype was normal. Normal levels of steroid sulfatase activity and 7-dehydrocholesterol ruled out X-linked ichthyosis and Smith-Lemli-Opitz syndrome, respectively. Postnatally, basal and stimulated cortisol and ACTH levels were low. Other pituitary functions were normal, suggesting the diagnosis of IAD. The patient was treated with a stress dose of hydrocortisone on day 2 of life, which was tapered to a maintenance dose. At the time of this writing, he was 7 months old, with normal growth and development. Recently, loss-of-function mutations in the human TPIT gene were detected in autosomal recessive IAD. TPIT is a cell-restricted T-box transcription factor that is important for the terminal differentiation of pituitary corticotrophs. Therefore, we performed molecular analysis of the TPIT gene, which revealed a new mutation (IVS4+1G>A) that affects the first nucleotide of the splice site at the 5' end of the fourth intron. This stop codon probably leads to loss of TPIT function by nonsense-mediated mRNA decay, as it does for other TPIT nonsense mutations. We recommend that pregnant women with an isolated low estriol level of unexplained etiology be referred for additional evaluation by a multidisciplinary team that includes a geneticist and pediatric endocrinologist. Prompt ACTH testing in the first postnatal days will allow for early diagnosis. The immediate institution of glucocorticoid therapy, with proper instructions for stress management, can prevent unnecessary neonatal death secondary to an easily treatable disease.

X-linked adrenal hypoplasia congenita and hypogonadotropic hypogonadism: report on new mutation of the DAX-1 gene in two siblings

OBJECTIVE

Adrenal hypoplasia congenita (AHC) is a hereditary disorder that leads to adrenal insufficiency and hypogonadotropic hypogonadism (HHG) in childhood. The gene responsible for the X-linked form, DAX-1 (dosage-sensitive sex-reversal, AHC, on the X-chromosome, gene 1)/NR0B1, encodes for an unusual member of the nuclear receptor superfamily. Deletions and point mutations in the DAX-1 gene have been described in more than 70 AHC families. Inter- and intra-familial variability in the clinical presentation of AHC has been observed. Here we present the clinical and genetic data of two brothers affected by AHC.

SUBJECTS AND METHODS

Clinical heterogeneity was observed in the two brothers: the first presented with adrenal insufficiency in early infancy, while the second required no substitution therapy until 4 yr of age. Interestingly, mineralcorticoid hormone deficiency preceded cortisol deficiency in both brothers. HHG was observed at pubertal age in both patients and required substitution therapy with gonadal steroids.

RESULTS

Sequence analysis revealed a novel mutation in the DAX-1 gene in the two brothers and in their carrier mother. The mutation, a three nucleotide deletion, results in the loss of leucine 278 (del278L). A missense mutation affecting the same leucine (L278P) was previously shown to cause marked reduction of repressor function with respect to the wild type protein in transcription assays.

CONCLUSIONS

Missense mutations or amino acid loss in the DAX-1 gene are very rare. Their identification and genotype-phenotype correlation are important for the characterization of protein function and for patient management.

Novel deletion mutations of the DAX1 (NR0B1) gene in two Taiwanese families with X-linked adrenal hypoplasia congenita

OBJECTIVE

To analyze the DAX1 (NROB1) gene in Taiwanese families with adrenal hypoplasia congenita.

PATIENTS AND METHODS

Two unrelated Taiwanese patients were followed up at our pediatric endocrine clinic. Both patients presented with adrenal crisis. One patient entered puberty spontaneously. However, arrest of puberty was noted in the following years and hypogonadotropic hypogonadism was confirmed by GnRH test. The other patient was still prepubertal. Sequencing of the DAX1 (NROB1) gene was carried out in both patients and their respective family members.

RESULTS

Two different novel mutations were identified. The first patient had one base (G) deletion at nucleotide 159, resulting in a frame-shift and a premature stop codon at position 84. The other patient had one base (G) deletion at nucleotide 831, leading to a frameshift and a premature stop codon at position 371. Family studies revealed that their mothers and sisters were heterozygotes for the mutations while their maternal grandmothers did not carry the mutations.

CONCLUSIONS

Two Taiwanese patients with adrenal hypoplasia congenita were detected to have novel mutations of the DAX1 (NR0B1) gene. Family studies suggested that such mutations resulted from de novo mutation of the DAX1 (NROB1) gene in their mothers. These data indicate that molecular analysis of the DAX1 (NR0B1) gene is important for the diagnosis and genetic counseling of children with primary adrenal insufficiency.

Congenital adrenal hypoplasia and male pseudohermaphroditism due to DAX1 mutation, SF1 mutation or neither: a patient report

A 15 year-old African American phenotypic female with congenital adrenal hypoplasia and intra-abdominal testes is described; she received cortisone acetate, 9alpha-Florinef, Premarin and Provera for maintenance therapy. Evaluation for DAX1, SF1 mutations using Southern blotting, PCR, PCR amplification, coding sequences, and splice site analyses have not detected any genetic abnormalities. While only 30% of the reported DAX1 mutation defects have been identified by a variety of genetic laboratory techniques, it remains probable that this unusual patient has either a DAX1 or SF1 mutation defect. A Wnt-4 defect was not evaluated.

IMAGe syndrome: a complex disorder affecting growth, adrenal and gonadal function, and skeletal development

IMAGe syndrome (intrauterine growth restriction, metaphyseal dysplasia, adrenal hypoplasia congenita, genital abnormalities; MIM 300290) is a multisystem disorder with a broad phenotype, which, if unrecognized, may result in major and possibly life-threatening complications. Initial clinical features overlap with those of Russell-Silver syndrome (RSS) and isolated growth hormone (GH) deficiency, conditions from which it must be distinguished. We report an Australian male with adrenal hypoplasia congenita (AHC) in association with IMAGe syndrome. The patient had intrauterine growth restriction (IUGR) and dysmorphic features comprising small, low-set ears, micrognathia, bilateral cryptorchidism, micropenis, and skeletal abnormalities. Signs of adrenal insufficiency occurred at aged 4.6 years. Our patient differs from those previously described by the late onset of adrenal insufficiency and the presence of GH deficiency. IMAGe is a complex syndrome involving dysmorphic features; disorders of growth, gonadal, and adrenal function; and skeletal abnormalities.

Adrenal insufficiency and abnormal genitalia in a 46XX female with Smith-Lemli-Opitz syndrome

OBJECTIVE

To report the first case of a 46XX female infant with Smith-Lemli-Opitz syndrome (SLOS), adrenal insufficiency and abnormal genitalia.

METHODS

The patient was assessed for hormonal status on day 4 and 6 months later and was followed-up from the study time (2.5 years of age).

RESULTS

The patient had a persistent urogenital sinus, posterior labial fusion without clitoromegaly. She presented with a salt-wasting syndrome on day 4. Adrenal insufficiency was confirmed. Adrenal androgen levels, including 17-hydroxyprogesterone and 11-deoxycortisol were moderately elevated.

CONCLUSION

Children with SLOS should be assessed for adrenal insufficiency. In female infants, abnormal external genitalia can be observed even if the precise mechanism behind these abnormalities is yet to be determined.

Mental retardation in a boy with congenital adrenal hypoplasia: a clue to contiguous gene syndrome involving DAX1 and IL1RAPL

We report on a 2 years and 9 months old Japanese boy with adrenal hypoplasia and mental retardation (MR) (developmental quotient approximately 60) which occurred in the absence of severe adrenal crisis and resultant brain damage. Cytogenetic and molecular studies were performed in this boy and his parents with normal phenotype, showing that the boy had a maternally derived approximately 2 Mb interstitial Xp deletion involving DAX1 (DSS-AHC critical region on the X chromosome, gene 1) for adrenal hypoplasia congenita and disrupting IL1RAPL (interleukin-1 receptor accessory protein-like) for non-specific MR. The results explain the development of MR in this boy in terms of contiguous gene syndrome, and suggest the importance of IL1RAPL analysis in patients with adrenal hypoplasia and MR.

[A peculiar form of neonatal adrenal insufficiency: the IMAGe association. Two new cases]

We report two siblings with an IMAGe syndrome. IMAGe is a newly reported syndrome characterized by the association of intra-uterine growth retardation, metaphyseal dysplasia, congenital adrenal hypoplasia and genital anomalies. This clinical association has only been described in five unrelated males. These two additional patients (one brother and one sister) suggest an autosomal recessive inheritance although identification of new cases will give further insight into the pathogenesis. The radiologic signs of osteopenia and metaphyseal dysplasia can suggest this diagnosis in affected individuals.

IMAGe association: additional clinical features and evidence for recessive autosomal inheritance

Congenital adrenal hypoplasia (CAH) normally occurs in the neonatal period, with patients presenting with more or less severe salt-wasting syndrome. X-linked CAH has been associated with mutations in the DAX-1 gene, and boys have also been shown to have hypogonadotrophic hypogonadism. Recently, in three unrelated boys, CAH was associated with intrauterine growth retardation (IUGR), metaphyseal dysplasia and genital abnormalities, defining a new association called IMAGe. We now report four additional patients with this association, including the first living female. The four patients belong to two unrelated families (one brother and one sister from each family). These patients have the main clinical characteristics of IMAGe association: IUGR, facial dysmorphy (frontal bossing, broad nasal bridge, low-set ears), short limbs due to metaphyseal dysplasia, and adrenal insufficiency. As these patients are older than the initial three patients, we can also describe additional features: short adult height, normal puberty in boys as well as in the living girl. The boys have hypospadias associated with micropenis. The living girl came to clinical attention at the age of 5 years as a result of a familial survey, and careful questioning revealed that she had been suffering from mild adrenal insufficiency since early childhood. At least one boy has congenital hypotonia due to muscular dystrophy. In conclusion, these four new cases display familial transmission, strongly suggesting Mendelian autosomal recessive inheritance. Adrenal insufficiency may be mild. Hypotonia, described in all the patients, might be related to paucisymptomatic muscular dystrophy, as this condition is clearly heterogeneous varying with regard to severity, associated manifestations and outcome. If this symptom is part of the syndrome, which we cannot assume, it could help to localize the candidate gene.

Compound heterozygous mutations in the cholesterol side-chain cleavage enzyme gene (CYP11A) cause congenital adrenal insufficiency in humans

Cholesterol side-chain cleavage enzyme (P450scc) catalyzes the conversion of cholesterol to pregnenolone in mitochondria, which is the first step in the biosynthesis of all steroid hormones. Until now, no homozygous or compound heterozygous mutations in CYP11A have been described in humans. Here we describe novel compound heterozygous mutations in CYP11A in a patient with congenital adrenal insufficiency born to healthy parents. One mutation, a maternally inherited R353W mutation, resulted in markedly reduced P450scc activity by the single amino acid substitution, indicating that Arg(353) is a crucial amino acid residue for P450scc activity. The other mutation, a de novo A189V mutation in the paternal allele, did not affect the P450scc activity by the single amino acid substitution and turned out to be a splicing mutation, which created a novel alternative splice-donor site. It resulted in a deletion of 61 nucleotides in the open reading frame and thus partially inactivated CYP11A. These experimental data are consistent with the clinical findings indicating that the patient had partially preserved ability to synthesize adrenal steroid hormones. This is the first report of the compound heterozygote for the CYP11A mutations with congenital adrenal insufficiency and the phenotypically normal heterozygote in humans.

X-linked adrenal hypoplasia congenita is caused by abnormal nuclear localization of the DAX-1 protein

Mutations in the DAX-1 [dosage-sensitive sex reversal-adrenal hypoplasia congenita (AHC) critical region on the X chromosome; NR0B1] gene cause X-linked AHC associated with hypogonadotropic hypogonadism. DAX-1 encodes an unusual orphan member of the nuclear hormone receptor superfamily, acting as a transcriptional repressor of genes involved in the steroidogenic pathway. All DAX-1 mutations found in AHC patients alter the protein C terminus, which shares similarity to the ligand binding domain of nuclear hormone receptors and bears transcriptional repressor activity. This property is invariably impaired in DAX-1 AHC mutants. Here we show that the localization of DAX-1 AHC mutant proteins is drastically shifted toward the cytoplasm, even if their nuclear localization signal, which resides in the N terminal of the protein, is intact. Cytoplasmic localization of DAX-1 AHC mutants correlates with an impairment in their transcriptional repression activity. These results reveal a critical role of an intact C terminus in determining DAX-1 subcellular localization and constitute an important example of a defect in human organogenesis caused by impaired nuclear localization of a transcription factor.