Familial cytomegalic adrenocortical hypoplasia: an X-linked syndrome of pubertal failure

Genetics of hypogonadotropic hypogonadism

Male congenital hypogonadotropic hypogonadism (CHH) is a heterogenous group of genetic disorders that cause impairment in the production or action of gonadotropin releasing hormone (GnRH). These defects result in dysfunction of the hypothalamic-pituitary-gonadal hormone axis, leading to low testosterone levels and impaired fertility. Genetic testing techniques have expanded our knowledge of the underlying mechanisms contributing to CHH including over 30 genes to date implicated in the development of CHH. In some cases, non-reproductive signs or symptoms can give clues as to the putative genetic etiology, but many cases remain undiagnosed with less than 50% identified with a specific gene defect. This leads to many patients labelled as "idiopathic hypogonadotropic hypogonadism". Medical and family history as well as physical exam and laboratory features can aid in the identification of hypogonadotropic hypogonadism (HH) that is associated with specific medical syndromes or associated with other pituitary hormonal deficiencies. Genetic testing strategies are moving away from the classic practice of testing for only a few of the most commonly affected genes and instead utilizing next generation sequencing techniques that allow testing of numerous potential gene targets simultaneously. Treatment of CHH is dependent on the individual's desire to preserve fertility and commonly include human chorionic gonadotropin (hCG) and recombinant follicle stimulating hormone (rFSH) to stimulate testosterone production and spermatogenesis. In situations where fertility is not desired, testosterone replacement therapies are widely offered in order to maintain virilization and sexual function.

Perspectives in Pediatric Pathology, Chapter 22. Testicular Involvement in Systemic Diseases

Normal testicular physiology requires appropriate function of endocrine glands and other tissues. Testicular lesions have been described in disorders involving the hypothalamus-hypophysis, thyroid glands, adrenal glands, pancreas, liver, kidney, and gastrointestinal tract. Testicular abnormalities can also associate with chronic anemia, obesity, and neoplasia. Although many of the disorders that affect the above-mentioned glands and tissues are congenital, acquired lesions may result in hypogonadism in children and adolescents.

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

X-linked adrenal hypoplasia congenita is caused by the mutation of DAX-1 gene (dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1), and can occur as part of a contiguous gene deletion syndrome in association with glycerol kinase (GK) deficiency, Duchenne muscular dystrophy and X-linked interleukin-1 receptor accessory protein-like 1 (IL1RAPL1) gene deficiency. It is usually associated with hypogonadotropic hypogonadism, although in rare cases, it has been reported to occur in normal puberty or even central precocious puberty. This study addresses a case in which central precocious puberty developed in a boy with X-linked adrenal hypoplasia congenita who had complete deletion of the genes DAX-1, GK and IL1RAPL1 (Xp21 contiguous gene deletion syndrome). Initially he was admitted for the management of adrenal crisis at the age of 2 months, and managed with hydrocortisone and florinef. At 45 months of age, his each testicular volumes of 4 mL and a penile length of 5 cm were noted, with pubic hair of Tanner stage 2. His bone age was advanced and a gonadotropin-releasing hormone (GnRH) stimulation test showed a luteinizing hormone peak of 8.26 IU/L, confirming central precocious puberty. He was then treated with a GnRH agonist, as well as steroid replacement therapy. In Korea, this is the first case of central precocious puberty developed in a male patient with X-linked adrenal hypoplasia congenita.

Primary adrenal insufficiency caused by a novel mutation in DAX1 gene

Adrenal hypoplasia congenita (AHC) is a rare disorder. The X-linked form is related to mutations in the DAX1 (NROB1) gene. Here, we report a newborn who had a novel hemizygous frameshift mutation in DAX1(c.543delA) and presented with primary adrenal failure that was initially misdiagnosed as congenital adrenal hyperplasia. This report highlights the value of genetic testing for definite diagnosis in children with primary adrenal failure due to abnormal adrenal gland development, providing the possibility both for presymptomatic, and in cases with a sibling with this condition, for prenatal diagnosis.

Massive neonatal adrenal enlargement due to cytomegaly, persistence of the transient cortex, and hyperplasia of the permanent cortex: findings in Cushing syndrome associated with hemihypertrophy

Described in this article is the massive enlargement of both adrenal glands in 3 newborns-2 girls and 1 boy. Two had hemihypertrophy and other congenital abnormalities but no identified genetic mutation; the third had genetically proven Beckwith-Wiedemann syndrome. Two had severe Cushing syndrome, the third had hypercortisolemia but no clinical Cushing syndrome. Bilateral adrenalectomy cured Cushing syndrome in the 2 with severe symptoms; total adrenal weight in these patients was 44 and 53 g, respectively. Unilateral adrenalectomy was performed in the third patient: the gland weighed 52 g; postoperatively, the patient's hypercortisolemia normalized, and, concomitantly, the enlarged contralateral adrenal gland had a 5-fold decrease in size with slight enlargement 6 years postoperatively. Microscopically, the 3 patients had similar pathology: massive adrenal enlargement due to a combination of cytomegaly, persistence of the transient cortex, and hyperplasia of the permanent cortex. The pathologic findings were most likely the result of the genetic mutation identified in 1 patient and of an unknown mutation in the remaining 2 patients.

Hypogonadotropic hypogonadism in subjects with DAX1 mutations

DAX1 (dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1; also known as NROB1, nuclear receptor subfamily 0, group B, member 1) encodes a nuclear receptor that is expressed in embryonic stem (ES) cells, steroidogenic tissues (gonads, adrenals), the ventromedial hypothalamus (VMH), and pituitary gonadotropes. Humans with DAX1 mutations develop an X-linked syndrome referred to as adrenal hypoplasia congenita (AHC). These boys typically present in infancy with adrenal failure but later fail to undergo puberty because of hypogonadotropic hypogonadism (HHG). The adrenal failure reflects a developmental abnormality in the transition of the fetal to adult zone, resulting in glucocorticoid and mineralocorticoid deficiency. The etiology of HHG involves a combined and variable deficiency of hypothalamic GnRH secretion and/or pituitary responsiveness to GnRH resulting in low LH, FSH and testosterone. Treatment with exogenous gonadotropins generally does not induce spermatogenesis. Animal models indicate that DAX1 also plays a critical role in testis development and function. As a nuclear receptor, DAX1 has been shown to function as a transcriptional repressor, particularly of pathways regulated by other nuclear receptors, such as steroidogenic factor 1 (SF1). In addition to reproductive tissues, DAX1 is also expressed at high levels in ES cells and plays a role in the maintenance of pluripotentiality. Here we review the clinical manifestations associated with DAX1 mutations as well as the evolving information about its function based on animal models and in vitro studies.

Evidence of adrenal failure in aging Dax1-deficient mice

Dosage-sensitive sex reversal, adrenal hypoplasia congenita (AHC) critical region on the X chromosome, gene 1 (Dax1) is an orphan nuclear receptor essential for development and function of the mammalian adrenal cortex and gonads. DAX1 was cloned as the gene responsible for X-linked AHC, which is characterized by adrenocortical failure necessitating glucocorticoid replacement. Contrary to these human data, young mice with genetic Dax1 knockout (Dax1(-/Y)) exhibit adrenocortical hyperfunction, consistent with the historic description of Dax1 as a transcriptional repressor that inhibits steroidogenic factor 1-dependent steroidogenesis. This paradox of molecular function and two apparently opposite phenotypes associated with Dax1 deficiency in mice and humans is compounded by the recent observations that under certain circumstances, Dax1 can serve as a transcriptional activator of steroidogenic factor 1. The recently revealed role of Dax1 in embryonic stem cell pluripotency, together with the observation that its expression in the adult adrenal is restricted to the subcapsular cortex, where presumptive undifferentiated progenitor cells reside, has led us to reexamine the phenotype of Dax1(-/Y) mice in order to reconcile the conflicting mouse and human data. In this report, we demonstrate that although young Dax1(-/Y) mice have enhanced steroidogenesis and subcapsular adrenocortical proliferation, as these mice age, they exhibit declining adrenal growth, decreasing adrenal steroidogenic capacity, and a reversal of their initial enhanced hormonal sensitivity. Together with a marked adrenal dysplasia in aging mice, these data reveal that both Dax1(-/Y) mice and patients with X-linked AHC exhibit adrenal failure that is consistent with adrenocortical subcapsular progenitor cell depletion and argue for a significant role of Dax1 in maintenance of these cells.

Clinical and molecular genetic characteristic of 10 cases with congenital adrenal hypoplasia caused by DAX-1 gene defects

X-linked congenital adrenal hypoplasia (CAH) is one of the most widespread forms of congenital hypocortisolism in boys. The disease is caused by defects in the NR0B1 gene that encodes for DAX1 protein. CAH manifests itself largely as adrenal insufficiency in young children and hypogonadotropic hypogonadism developing by the pubertal period. This paper describes 10 patients presenting with X-linked form of congenital adrenal hypoplasia. In six of them adrenal insufficiency was apparent during the first month of life and in the remaining four at a later time (up to the age of 13 years). Hypogonadism was diagnosed in all the patients (n=7) who reached the age of 15 by the moment of the last examination. Diagnosis of CAH was confirmed by molecular genetic analysis in all the ten cases. Nine different mutations in the NR0B1 gene were identified.

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.

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.

A new DAX1 gene mutation associated with congenital adrenal hypoplasia and hypogonadotropic hypogonadism

We report on a DAX1 gene investigation in a patient with X-linked adrenal hypoplasia congenita (AHC) and hypogonadotropic hypogonadism (HH) in order to identify mutations causing this disorder and to confirm the clinical diagnosis. The description of the clinical course of the condition with a detailed documentation of longitudinal data is also reported. A male newborn was referred at 45 days of life because of vomiting, dehydration, and weight loss. The diagnosis was primary adrenal insufficiency. The appropriateness of glucocorticoid therapy during the prepubertal period was difficult to judge because of elevated ACTH levels on one hand and progressive retardation of bone age on the other hand. Basal and GnRH stimulated gonadotropin levels remained low during the entire period of examination and exogenous gonadotropin treatment was begun. This had to be interrupted at age 14.6 years because of the occurrence of a 3rd degree anaplastic ependimoma of the left posterior-parietal region, without apparent lepto-meningeal involvement. The molecular analysis of DAX1 gene of the propositus showed deletion of nucleotides AAT in exon 2, resulting in the loss of the Asn430. No alterations were found in the mother and grandmother. This deleted residue lies in one of the helices forming the hydrophobic core of the ligand-binding domain (LBD); thus this mutation may be the cause of the observed phenotype. Further investigations are needed to verify its causal role in AHC associated with HH.

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.

Novel DAX1 mutations in X-linked adrenal hypoplasia congenita and hypogonadotrophic hypogonadism

OBJECTIVE

Mutations of the DAX1 gene (Dosage-sensitive sex reversal-Adrenal hypoplasia congenita critical region on the X chromosome gene 1), which encodes a novel orphan nuclear receptor, have been identified in patients with X-linked adrenal hypoplasia congenita (AHC) and hypogonadotrophic hypogonadism (HHG). We have investigated two kindreds with AHC and HHG for DAX1 mutations.

METHODS

Two kindreds with five affected males, four carrier females and four unaffected males were investigated. The gonadotrophin deficiency in three of the boys was observed to be partial until mid-puberty. DAX1 mutations in the entire 1413 bp coding region were sought by DNA sequence analysis.

RESULTS

Two DAX1 mutations, situated within exon 1, were detected. These consisted of an insertional mutation at codon 183 that led to a frameshift and a premature Stop at codon 184, and a missense mutation Leu278Pro that involved a highly conserved leucine residue within the proposed ligand binding domain. Co-segregation of these mutations with the disease in each family, and their absence from 107 alleles in 73 (39 males and 34 females) unrelated control individuals, was demonstrated by allele specific oligonucleotide hybridization (ASO) analysis for the insertional mutation, and by Ban I restriction endonuclease analysis for the missense mutation.

CONCLUSIONS

Two novel DAX1 mutations have been detected in two families with adrenal hypoplasia and hypogonadotrophic hypogonadism. The finding of partial gonadotrophin deficiency in the affected males from these families is notable and an early recognition of such a possibility in a patient, which may be facilitated by DAX1 mutational analysis, may help to prevent the sequelae of delayed androgen replacement therapy.

Congenital adrenal hypoplasia: clinical spectrum, experience with hormonal diagnosis, and report on new point mutations of the DAX-1 gene

X-linked congenital adrenal hypoplasia (AHC) is a rare developmental disorder of the human adrenal cortex and is caused by deletion or mutation of the DAX-1 gene, a recently discovered member of the nuclear hormone receptor superfamily. Hypogonadotropic hypogonadism is frequently associated with AHC. AHC occurs as part of a contiguous gene syndrome together with glycerol kinase deficiency (GKD) and Duchenne's muscular dystrophy. The present series, collected over the past 2 decades, includes 18 AHC boys from 16 families: 4 with AHC, GKD, and Duchenne's muscular dystrophy; 2 with AHC and GKD; and 12 with AHC (5 young adults with hypogonadotropic hypogonadism). Most of the boys presented with salt wasting and hyperpigmentation during the neonatal period. Plasma steroid determinations performed in the first weeks of life often showed confusing results, probably caused by steroids produced in the neonates' persisting fetocortex. Aldosterone deficiency usually preceded cortisol deficiency, which explains why the patients more often presented with salt-wasting rather than with hypoglycemic symptoms. An ACTH test was often necessary to detect cortisol deficiency in the very young infants. In some patients, serial testing was necessary to establish the correct diagnosis. In 4 boys studied during the first 3 months after birth, we found pubertal LH, FSH, and testosterone plasma levels indicating postnatal transient activation of the hypothalamic-pituitary-gonadal axis as in normal boys. Previous studies have shown that the DAX-1 gene is deleted in the AHC patients with a contiguous gene syndrome and is mutated in nondeletion patients. Most of the point mutations identified in AHC patients were frameshift mutations and stop mutations. In the 15 patients available for molecular analysis of the DAX-1 gene, there were large deletions in 6 patients and point mutations in another 7 patients. All of the point mutations identified in the present study resulted in a nonfunctional truncated DAX-1 protein. Two brothers with primary adrenal insufficiency and a medical history that strongly suggested AHC had no mutation in the DAX-1 gene. Thus, additional, as yet unknown genes must play a part in normal adrenal cortical development.

DAX1 mutations map to putative structural domains in a deduced three-dimensional model

The DAX1 protein is an orphan nuclear hormone receptor based on sequence similarity in the putative ligand-binding domain (LBD). DAX1 mutations result in X-linked adrenal hypoplasia congenita (AHC). Our objective was to identify DAX1 mutations in a series of families, to determine the types of mutations resulting in AHC and to locate single-amino-acid changes in a DAX1 structural model. The 14 new mutations identified among our 17 families with AHC brought the total number of families with AHC to 48 and the number of reported mutations to 42; 1 family showed gonadal mosaicism. These mutations included 23 frameshift, 12 nonsense, and six missense mutations and one single-codon deletion. We mapped the seven single-amino-acid changes to a homology model constructed by use of the three-dimensional crystal structures of the thyroid-hormone receptor and retinoid X receptor alpha. All single-amino-acid changes mapped to the C-terminal half of the DAX1 protein, in the conserved hydrophobic core of the putative LBD, and none affected residues expected to interact directly with a ligand. We conclude that most genetic alterations in DAX1 are frameshift or nonsense mutations and speculate that the codon deletion and missense mutations give insight into the structure and function of DAX1.

Adrenal hypoplasia congenita with hypogonadotropic hypogonadism: evidence that DAX-1 mutations lead to combined hypothalmic and pituitary defects in gonadotropin production

Adrenal hypoplasia congenita (AHC) is an X-linked disorder that typically presents with adrenal insufficiency during infancy. Hypogonadotropic hypogonadism (HHG) has been identified as a component of this disorder in affected individuals who survive into childhood. Recently, AHC was shown to be caused by mutations in DAX-1, a protein that is structurally similar in its carboxyterminal region to orphan nuclear receptors. We studied two kindreds with clinical features of AHC and HHG. DAX-1 mutations were identified in both families. In the JW kindred, a single base deletion at nucleotide 1219 was accompanied by an additional base substitution that resulted in a frameshift mutation at codon 329 followed by premature termination. In the MH kindred, a GGAT duplication at codon 418 caused a frameshift that also resulted in truncation of DAX-1. Baseline luteinizing hormone (LIT), follicle-stimulating hormone (FSH), and free-alpha-subunit (FAS) levels were determined during 24 h of frequent (q10 min) venous sampling. In patient MH, baseline LH levels were low, but FAS levels were within the normal range. In contrast, in patient JW, the mean LH and FSH were within the normal range during baseline sampling, but LH secretion was erratic rather than showing typical pulses. FAS was apulsatile for much of the day, but a surge was seen over a 3-4-h period. Pulsatile gonadotropin releasing hormone (GnRH) (25 ng/kg) was administered every 2 h for 7 d to assess pituitary responsiveness to exogenous GnRH. MH did not exhibit a gonadotropin response to pulsatile GnRH. JW exhibited a normal response to the first pulse of GnRH, but there was no increase in FAS. In contrast to the priming effect of GnRH in GnRH-deficient patients with Kallmann syndrome, GnRH pulses caused minimal secretory responses of LH and no FAS responses in patient JW. The initial LH response in patient JW implies a deficiency in hypothalamic GnRH. On the other hand, the failure to respond to pulsatile GnRH is consistent with a pituitary defect in gonadotropin production. These two cases exemplify the phenotypic heterogeneity of AHC/HHG, and suggest that DAX-1 mutations impair gonadotropin production by acting at both the hypothalamic and pituitary levels.

A special case of congenital adrenal hypoplasia and acute bilateral infantile striatal necrosis

Isolated mineralocorticoid deficiency is described in a 5-week-old boy. The deficiency progressed to general adrenal insufficiency during the boy's first year of life. The family history suggested X-linked inheritance. At 18 months of age the patient developed acute bilateral infantile striatal necrosis, which might suggest a possible relationship between both entities.

Gene deletion causing adrenal hypoplasia congenita and hypogonadotrophic hypogonadism

We report a patient with X-linked adrenal hypoplasia congenita and hypogonadotrophic hypogonadism in whom there were no clinical or biochemical features of either glycerol kinase deficiency or Duchenne muscular dystrophy. (The adrenal hypoplasia congenita and glycerol kinase loci map in Xp21 distal to Duchenne muscular dystrophy, and proximal to DXS727). DNA isolated from our patient was analysed by PCR amplification with primers for appropriate loci in the Xp21 region. This analysis revealed the absence of DXS319, which lies near the adrenal hypoplasia congenita deletion critical region, and the presence of DXS727, which is distal to the gene. The absence of glycerol kinase deficiency biochemically and clinically was consistent with the presence of one glycerol kinase exon product from PCR primers P17/P18 which lies within the glycerol kinase gene. The hypogonadotrophic hypogonadism is universally found in X-linked adrenal hypoplasia congenita and is thought to be pituitary in origin. These findings suggest that a gene locus resulting in hypogonadotrophic hypogonadism is present in the Xp21 region and is an integral part of the adrenal hypoplasia congenita gene or in close relationship to it.

Progressive high frequency hearing loss: an additional feature in the syndrome of congenital adrenal hypoplasia and gonadotrophin deficiency

In an earlier report, we found that X-linked congenital adrenal hypoplasia may be associated with gonadotrophin deficiency. This combination has since been confirmed by many others. At the last examination, our patients were 22.4, 19.9 and 17.5 years old. They were doing well on replacement therapy with hydrocortisone, fluorohydrocortisone, and long-acting testosterone, but in all of them, a progressive hearing loss had appeared, starting at high frequencies at about 14 years of age. The loss progressed with age to lower frequencies, and the oldest patient had some remaining hearing capacity at 125-500 Hz only with a perceptive hearing loss of -95 dB at frequencies above 500 Hz. It is concluded that patients with this syndrome should be examined for hearing loss. X-linked adrenal hypoplasia may also be associated with glycerol kinase deficiency and myopathy. A molecular XP-deletion has suggested a locus for hypogonadotrophic hypogonadism distal to the glycerol kinase and adrenal hypoplasia loci. The observations in our patients suggest that the locus for at least this type of X-linked deafness may be in the same area.

Three cases of congenital adrenal hypoplasia: a cause of salt-wasting and mortality in the neonatal period

Three infants with congenital adrenal hypoplasia are described. The two surviving infants were detected and successfully treated in the neonatal period due to a suggestive family history (Case 1) and antenatal maternal oestriol screening (Case 2). The modes of inheritance, diverse clinical presentation, associated conditions, diagnostic work-up and pathology of congenital adrenal hypoplasia in these three infants is discussed.

Molecular Xp deletion in a male: suggestion of a locus for hypogonadotropic hypogonadism distal to the glycerol kinase and adrenal hypoplasia loci

We have analyzed one patient with a syndrome of glycerol kinase deficiency (GKD), adrenal hypoplasia (AH), mental retardation (MR) and hypogonadotropic hypogonadism (HH). Although a cytogenetic analysis of the patient failed to reveal any detectable chromosomal abnormality, Southern blot analysis, using DNA probes from the Xp21-Xp22 region, revealed a molecular deletion localized between the DXS41 and the DXS268 loci. Our results together with those of others (van Ommen et al. 1986, 1987, Francke et al. 1987, Yates et al. 1987, Chelly et al. 1988) suggest that the GK gene is located between the DXS68 and DXS268 loci. In addition, we propose a locus for HH in Xp, distal to the genes for GK and AH.

Congenital adrenal hypoplasia and selective absence of pituitary luteinizing hormone: a new autosomal recessive syndrome

Congenital hypoplasia of the adrenal glands (CHA) is a rare condition, particularly in the absence of a central nervous system (CNS) anomaly. Two major types of CHA have been described in the setting of an apparently normal CNS and pituitary: a cytomegalic type usually with X-linked recessive inheritance and a miniature adult type that, when hereditary, is an autosomal recessive trait. Glycerol kinase deficiency (GKD) is an X-linked recessive trait, and it may be associated with CHA and adrenal insufficiency, presumably because of deletion of adjacent X-linked loci. We report on three sibling infants, one male and two females, with normal CNS and lethal CHA of the miniature adult type, selective absence of pituitary LH; two of the infants also had glycerol kinase (GK) activity that was decreased but not in the GKD range. Restriction fragment length polymorphism (RFLP) analysis of X chromosome markers located at Xp21-p22 was carried out on the maternal grandfather, both parents, two of three affected infants, and a living normal brother. The results excluded the X-linked type of this disorder associated with GKD in this family. Autosomal recessive inheritance is most likely.

Deletion on the X chromosome detected by direct DNA analysis in one of two unrelated boys with glycerol kinase deficiency, adrenal hypoplasia, and Duchenne muscular dystrophy

In studies of the X chromosomes of two unrelated boys with adrenal hypoplasia, glycerol kinase deficiency, Duchenne muscular dystrophy, and mental retardation, conventional G banding did not reveal any numerical or structural abnormality, but direct DNA analysis with the X short-arm probes 754, C7, and OCT revealed a deletion in 1 of these patients. It is likely that both boys have a deletion at Xp21 affecting a number of closely linked disease-specific gene loci.

Recently recognized chromosomal defects of clinical importance

We review those conditions which have recently been recognized to be associated with small, sometimes difficult to detect, chromosomal abnormalities. These include the Prader-Willi syndrome and X-linked mental retardation.

Histopathology of the human adrenal cortex

The morphological features of the adult human adrenal cortex are described with particular respect to changes induced by alterations in function of the hypothalamo-pituitary axis. The occurrence of nodules in the normal and hyperplastic cortex (Cushing's and Conn's syndromes) is discussed in relation to the diagnostic problems that they still pose. Explanations based on the normal mechanisms of functional zonation in the cortex are provided for the different cell types which comprise cortical neoplasms associated with various syndromes of hypercorticalism (Cushing's, adrenogenital and Conn's syndromes), together with morphological and functional criteria to distinguish adenomas from carcinomas.

Clinical presentation, growth, and pubertal development in Addison's disease

The clinical course of eight boys and six girls with Addison's disease has been reviewed. Adrenal antibodies were found in five boys and five girls, and four children showed clinical evidence of other autoimmune disease (hypoparathyroidism (three); diabetes (one)). The presentation was insidious in 12 children but acute in two. On treatment, linear growth was normal and, with the exception of one girl with theca cell antibodies, pubertal development proceeded normally in the older patients.

Contrasting effects of subcutaneous pulsatile GnRH therapy in congenital adrenal hypoplasia and Kallmann's syndrome

A patient with congenital adrenal hypoplasia (AH) and hypogonadotrophic hypogonadism was treated with pulsatile subcutaneous GnRH therapy for 16 weeks in an attempt to induce puberty. No rise in serum LH or FSH concentrations occurred despite increasing doses of GnRH (2.8 micrograms/pulse-22.4 micrograms/pulse). In contrast a similar programme of therapy successfully initiated the biochemical changes of puberty in a patient with Kallmann's syndrome. Both patients before therapy had low basal serum LH and FSH concentrations with blunted LH and FSH responses to GnRH stimulation. After 1 week, serum LH and FSH rose into the normal adult range in the patient with Kallmann's syndrome. This study fails to confirm a previous report which suggested that intermittent low dose GnRH therapy may be of value in inducing puberty in AH. The reasons for the difference of pituitary responsiveness to GnRH in AH and Kallmann's syndrome are unclear at present.

Congenital adrenal hypoplasia, progressive muscular dystrophy, and severe mental retardation, in association with glycerol kinase deficiency, in male sibs

A family is described with three male sibs suffering from congenital adrenal hypoplasia (CAH). In the two surviving brothers the disease is clinically further characterized by a Duchenne type muscular dystrophy, growth failure and severe mental retardation. Laboratory investigations revealed deficient activities of gonadotrophin and glycerol kinase. The clinical, biochemical and genetic findings in ths exceptional family are reported and discussed.

Congenital adrenal hypoplasia: two new cases

Two male adolescents with the X-linked form of congenital adrenal hypoplasia are described. Both grew slowly during childhood and adolescence and did not undergo pubertal development because of hypogonadotropic hypogonadism associated with the congenital adrenal hypoplasia. The severely delayed bone age in childhood is probably due to the adrenal androgen deficiency and suggests a role of these hormones in the prepubertal skeletal maturation. The failure of gonadotropin secretion still remains unexplained. A hypothalamic defect has been suggested, but further studies are necessary to clarify this hypothesis.

X-linked congenital adrenal hypoplasia. A study of five generations of a Greenlandic Family

In a Greenlandic family comprising 171 descendants in 5 generations, 11 boys had died with a clinical picture of adrenocortical insufficiency within three weeks of birth. Three treated male patients, who survived, were closely studied. The adrenal glands could not be identified by computed tomography. The clinical picture and biochemical studies were consistent with congenital adrenal hypoplasia. The pedigree indicates X-linked recessive inheritance. The pubertal development was delayed in two patients aged 14 years. LHRH stimulation yielded a significant rise in LH and FSH in at least one of the patients, adrenal androgen values were very low. A family instruction programme has been set up.