Congenital lipoid adrenal hyperplasia

Adrenal Dysfunction in Mitochondrial Diseases

Cortisol is central to several homeostatic mechanisms including the stress and immune response. Adrenal insufficiency and impaired cortisol production leads to severe, potentially fatal disorders. Several fundamental stages of steroidogenesis occur within the mitochondria. These dynamic organelles not only contribute ATP for steroidogenesis, but also detoxify harmful by-products generated during cortisol synthesis (reactive oxygen species). Mutations in nuclear or mitochondrial DNA that impair mitochondrial function lead to debilitating multi-system diseases. Recently, genetic variants that impair mitochondrial function have been identified in people with isolated cortisol insufficiency. This review aimed to clarify the association between mitochondrial diseases and adrenal insufficiency to produce cortisol. Mitochondrial diseases are rare and mitochondrial diseases that feature adrenal insufficiency are even rarer. We identified only 14 cases of adrenal insufficiency in people with confirmed mitochondrial diseases globally. In line with previous reviews, adrenal dysfunction was most prevalent in mitochondrial deletion syndromes (particularly Pearson syndrome and Kearns-Sayre syndrome) and with point mutations that compromised oxidative phosphorylation. Although adrenal insufficiency has been reported with mitochondrial diseases, the incidence reflects that expected in the general population. Thus, it is unlikely that mitochondrial mutations alone are responsible for an insufficiency to produce cortisol. More research is needed into the pathogenesis of adrenal disease in these individuals.

Congenital lipoid adrenal hyperplasia in a Saudi infant

Summary

Congenital lipoid adrenal hyperplasia (CLAH) is characterized by a defect in the STAR protein-encoding gene that attenuates all steroidogenesis pathways. Herein, we present the first reported case in Saudi Arabia of a 46 XY, phenotypically female infant with an unfamiliar, darkened complexion compared to the family's skin color. Based on the clinical and biochemical findings, CLAH was diagnosed and glucocorticoid replacement therapy was initiated. As a result, we suggest that pediatricians should always investigate the possibility of adrenal insufficiency when encountering unusual dark skin.

Learning points

Pediatricians should be prompted to rule out adrenal insufficiency in unexpectedly dark skin neonates. In such patients, pediatricians should not wait until the neonate develops an adrenal crisis. A low level of 17-hydroxyprogesterone does not always rule out the possibility of inherited adrenal gland disorders, and additional tests should be performed for early detection.

Disorders of Sex Development of Adrenal Origin

Disorders of Sex Development (DSD) are anomalies occurring in the process of fetal sexual differentiation that result in a discordance between the chromosomal sex and the sex of the gonads and/or the internal and/or external genitalia. Congenital disorders affecting adrenal function may be associated with DSD in both 46,XX and 46,XY individuals, but the pathogenic mechanisms differ. While in 46,XX cases, the adrenal steroidogenic disorder is responsible for the genital anomalies, in 46,XY patients DSD results from the associated testicular dysfunction. Primary adrenal insufficiency, characterized by a reduction in cortisol secretion and overproduction of ACTH, is the rule. In addition, patients may exhibit aldosterone deficiency leading to salt-wasting crises that may be life-threatening. The trophic effect of ACTH provokes congenital adrenal hyperplasia (CAH). Adrenal steroidogenic defects leading to 46,XX DSD are 21-hydroxylase deficiency, by far the most prevalent, and 11β-hydroxylase deficiency. Lipoid Congenital Adrenal Hyperplasia due to StAR defects, and cytochrome P450scc and P450c17 deficiencies cause DSD in 46,XY newborns. Mutations in SF1 may also result in combined adrenal and testicular failure leading to DSD in 46,XY individuals. Finally, impaired activities of 3βHSD2 or POR may lead to DSD in both 46,XX and 46,XY individuals. The pathophysiology, clinical presentation and management of the above-mentioned disorders are critically reviewed, with a special focus on the latest biomarkers and therapeutic development.

Steroidogenic electron-transfer factors and their diseases

Most steroidogenesis disorders are caused by mutations in genes encoding the steroidogenic enzymes, but work in the past 20 years has identified related disorders caused by mutations in the genes encoding the cofactors that transport electrons from NADPH to P450 enzymes. Most P450s are microsomal and require electron donation by P450 oxidoreductase (POR); by contrast, mitochondrial P450s require electron donation via ferredoxin reductase (FdxR) and ferredoxin (Fdx). POR deficiency is the most common and best-described of these new forms of congenital adrenal hyperplasia. Severe POR deficiency is characterized by the Antley-Bixler skeletal malformation syndrome and genital ambiguity in both sexes, and hence is easily recognized, but mild forms may present only with infertility and subtle disorders of steroidogenesis. The common POR polymorphism A503V reduces catalysis by P450c17 (17-hydroxylase/17,20-lyase) and the principal drugmetabolizing P450 enzymes. The 17,20-lyase activity of P450c17 requires the allosteric action of cytochrome b5, which promotes interaction of P450c17 with POR, with consequent electron transfer. Rare b5 mutations are one of several causes of 17,20-lyase deficiency. In addition to their roles with steroidogenic mitochondrial P450s, Fdx and FdxR participate in the synthesis of iron-sulfur clusters used by many enzymes. Disruptions in the assembly of Fe-S clusters is associated with Friedreich ataxia and Parkinson disease. Recent work has identified mutations in FdxR in patients with neuropathic hearing loss and visual impairment, somewhat resembling the global neurologic disorders seen with mitochondrial diseases. Impaired steroidogenesis is to be expected in such individuals, but this has not yet been studied.

Noninvasive prenatal test of single-gene disorders by linked-read direct haplotyping: application in various diseases

Direct haplotyping enables noninvasive prenatal testing (NIPT) without analyzing proband, which is a promising strategy for pregnancies at risk of an inherited single-gene disorder. Here, we aimed to expand the scope of single-gene disorders that NIPT using linked-read direct haplotyping would be applicable to. Three families at risk of myotonic dystrophy type 1, lipoid congenital adrenal hyperplasia, and Fukuyama congenital muscular dystrophy were recruited. All cases exhibited distinct characteristics that are often encountered as hurdles (i.e., repeat expansion, identical variants in both parents, and novel variants with retrotransposon insertion) in the universal clinical application of NIPT. Direct haplotyping of parental genomes was performed by linked-read sequencing, combined with allele-specific PCR, if necessary. Target DMPK, STAR, and FKTN genes in the maternal plasma DNA were sequenced. Posterior risk calculations and an Anderson-Darling test were performed to deduce the maternal and paternal inheritance, respectively. In all cases, we could predict the inheritance of maternal mutant allele with > 99.9% confidence, while paternal mutant alleles were not predicted to be inherited. Our study indicates that direct haplotyping and posterior risk calculation can be applied with subtle modifications to NIPT for the detection of an expanded range of diseases.

Clinical and genetic characterization of congenital lipoid adrenal hyperplasia

Disorders of steroid synthesis are a group of anomalies caused by defects in any step of conversion of cholesterol into steroid hormones. The disorders are characterized by defects leading to abnormalities of salt-water balance and/or sexual differentiation. Congenital lipoid adrenal hyperplasia (CLAH) is the most severe form of steroid synthesis disorder caused by the accumulation of cholesterol in the outer mitochondrial membrane due to steroidogenic acute regulatory protein (StAR) deficiency. Pathogenic sequence variants in the gene STAR encoding StAR protein leads to CLAH. In the present study, a Pakistani family was clinically diagnosed with the LAH phenotype. Sanger sequencing of STAR in the family revealed a novel homozygous nonsense mutation [c.295G>T, p.(Glu99*)] in the living affected individual. The study was designed to assist in carrier testing and prenatal diagnosis within the affected family. In addition, searching for common variants in the STAR gene would help in designing low-cost targeted variation testing in other patients.

Plea for a standardized imaging approach to disorders of sex development in neonates: consensus proposal from European Society of Paediatric Radiology task force

This consensus article elaborated by the European Society for Paediatric Radiology task force on gastrointestinal and genitourinary imaging is intended to standardize the imaging approach in newborns with disorders of sex development. These newborns represent a difficult and stressful situation necessitating a multidisciplinary team approach. Imaging plays an important role in the work-up but needs to be optimized and customized to the patient. Ultrasound plays the central role in assessing the genital anatomy. The examination must be conducted in a detailed and systematic way. It must include transabdominal and transperineal approaches with adapted high-resolution transducers. The pelvic cavity, the genital folds, the inguinal areas and the adrenals must be evaluated as well as the rest of the abdominal cavity. A reporting template is proposed. The indications of magnetic resonance imaging and cysto- and genitography are discussed as well as they may provide additional information. Imaging findings must be reported cautiously using neutral wording as much as possible.

The impact of CYP21A2 (P30L/I172N) genotype on female fertility in one family

Background

The simple virilizing (SV) form of congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder usually caused by steroid 21-hydroxylase deficiency due to I172N missense mutation at the CYP21A2 gene. Clinical presentation encompasses virilization of external genitalia in newborn females and pseudoprecocious puberty in both sexes, due to reactive androgen overproduction. The aim of this study was to present two sisters with an SV form of CAH and distinctive genotype, detected and treated since childhood with a poor compliance and poor metabolic control hindering the fertility.

Case presentation

We retrospectively reviewed the clinical, biochemical, and molecular data of two sisters with CAH a 46,XX karyotype when they reached an age of 35 and 38 years, respectively, and were attempting conception for several years. They had been diagnosed with SV form of CAH at the age of 7 and 9 years, respectively, by the standard clinical and biochemical procedures, presenting with severe virilization due to androgen excess. Follow-up was performed through standard methods of measurement of 17-OHP, testosterone, and ACTH. Clitoroplasty with vaginoplasty was performed at the age of 18 in the older sister. Using PCR/ACRS, we performed molecular analysis of the nine most common point CYP21A2 mutations in the patients and family members. The P30L/II72N genotype was observed in both sisters. They had inadequate metabolic control due to noncompliance until decision to conceive. IVF was performed three times in the older sister without success. Sufficient follicles were harvested and fertilized; however, the embryos were lost 3–5 days after implantations. The younger sister is preparing for IVF. She underwent follicle harvesting and the embryos were frozen awaiting appropriate hormonal balance for embryo transfer. The I172N mutation in the heterozygote state was observed in their other two sisters, whose fertility was unaffected.

Conclusions

Despite significant improvements over the last years in achieving fertility in female patients with SV CAH, it is highly dependent upon the severity of virilization and the metabolic control. The role of P30L mutation in infertility and unsuccessfully assisted reproduction remains to be elucidated.

Genetic testing of XY newborns with a suspected disorder of sex development

PURPOSE OF REVIEW

The current review focuses on the neonatal presentation of disorders of sex development, summarize the current approach to the evaluation of newborns and describes recent advances in understanding of underlying genetic aetiology of these conditions.

RECENT FINDINGS

Several possible candidate genes as well as other adverse environmental factors have been described as contributing to several clinical subgroups of 46,XY DSDs. Moreover, registry-based studies showed that infants with suspected DSD may have extragenital anomalies and in 46,XY cases, being small for gestational age (SGA), cardiac and neurological malformations are the commonest concomitant conditions.

SUMMARY

Considering that children and adults with DSD may be at risk of several comorbidities a clear aetiological diagnosis will guide further management. To date, a firm diagnosis is not reached in over half of the cases of 46,XY DSD. Whilst it is likely that improved diagnostic resources will bridge this gap in the future, the next challenge to the clinical community will be to show that such advances will result in an improvement in clinical care.

Lipocrinology - the relationship between lipids and endocrine function

While lipids are an integral part of the endocrine clinic, the opposite is not necessarily true. The lipocrinology framework addresses this lacuna, by highlighting the similarities and multiple relationships between lipid and endocrine function. It reinforces the need to screen (clinically or biochemically) all dyslipidemic patients for endocrine disease and appropriate endocrine patients for dyslipidemia. Thus, it aims to improve clinical care for persons with lipid abnormalities as well as endocrine disease.

Review: Placental mitochondrial function and structure in gestational disorders

The aetiology of many gestational disorders is still unknown. However, insufficient trans-placental nutrient and oxygen transfer due to abnormal placentation is characteristic of several pathologies, and may alter the function of placental mitochondria. Mitochondria are multifunctional organelles that respond to a wide range of stimuli - such as physiological changes in cellular energy demands or various pathologies - by reshaping via fusion or fission, increasing/decreasing in number, altering oxidative phosphorylation, and signalling cellular functions such as apoptosis. Mitochondrial function is integral to tissue functions including energy production, metabolism, and regulation of various cellular responses including response to oxidative stress. This review details the functions of placental mitochondria and investigates mitochondrial function and structure in gestational disorders including preeclampsia, intrauterine growth restriction, diabetes mellitus, and obesity. Placental mitochondrial dysfunction may be critical in a range of gestational disorders which have important implications for maternal and fetal/offspring health.

Fetal safety profile of aromatase inhibitors: Animal data

Aromatase inhibitors (AIs) are a class of drugs that act by blocking the production of estrogens from androgens. The current review concentrates on the prenatal developmental toxicity of AIs in experimental models. Available data indicate that AIs may affect pregnancy at human therapeutic or lower doses. The window of vulnerability to AIs is not limited to organogenesis, but also includes the preimplantation stage and fetal periods. Decreased embryo/fetal survival was the prominent treatment-related effect. Morphological anomalies noted in fetuses exposed to AIs included skeletal anomalies, abnormal head morphology, increased ano-genital distance in female fetuses, and minor urinary tract system anomalies. Placental enlargement was consistently reported in rats and non-human primates after maternal treatment with several AIs. In conclusion, data from basic scientific research suggest that low intensity exposure to AIs applied during a wide gestational window can profoundly affect prenatal development.

Intracellular cholesterol transport proteins: roles in health and disease

Effective cholesterol homoeostasis is essential in maintaining cellular function, and this is achieved by a network of lipid-responsive nuclear transcription factors, and enzymes, receptors and transporters subject to post-transcriptional and post-translational regulation, whereas loss of these elegant, tightly regulated homoeostatic responses is integral to disease pathologies. Recent data suggest that sterol-binding sensors, exchangers and transporters contribute to regulation of cellular cholesterol homoeostasis and that genetic overexpression or deletion, or mutations, in a number of these proteins are linked with diseases, including atherosclerosis, dyslipidaemia, diabetes, congenital lipoid adrenal hyperplasia, cancer, autosomal dominant hearing loss and male infertility. This review focuses on current evidence exploring the function of members of the ‘START’ (steroidogenic acute regulatory protein-related lipid transfer) and ‘ORP’ (oxysterol-binding protein-related proteins) families of sterol-binding proteins in sterol homoeostasis in eukaryotic cells, and the evidence that they represent valid therapeutic targets to alleviate human disease.

Retracted: Aetiology and clinical profile of children with 46, XY differences of sex development at an Indian referral centre

Retraction: 'Aetiology and clinical profile of children with 46, XY differences of sex development at an Indian referral centre' by Vasundhera Chauhan, Rima Dada, Vandana Jain The above article, published online on 8 August 2016 in Wiley Online Library (http://wileyonlinelibrary.com), has been retracted by agreement between the authors, the Journal Editors-in-Chief, Wolf-Bernhard Schill and Ralf Henkel, and Blackwell Verlag GmbH. The retraction has been agreed as the result of an unresolved dispute between the first author and a colleague research fellow due to the inclusion of data from patients who were simultaneously enrolled in two studies being conducted separately by the two parties. Reference Chauhan, V., Dada, R. and Jain, V. (2016), Aetiology and clinical profile of children with 46, XY differences of sex development at an Indian referral centre. Andrologia. doi:10.1111/and.12663.

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.

Infertility and Reproductive Function in Patients with Congenital Adrenal Hyperplasia: Pathophysiology, Advances in Management, and Recent Outcomes

Individuals with congenital adrenal hyperplasia have reduced fertility. However, reproductive outcomes have improved over the years. This review provides an update on the multiple pathologic processes that contribute to reduced fertility in both sexes, from alterations of the hypothalamic-pituitary-gonadal axis to the direct effect on gonadal function by elevated circulating adrenal androgens. In addition, elevated serum progesterone concentrations may hinder ovulation and embryo implantation in women, whereas in men testicular adrenal rest tumors can be a major cause of infertility. Suppression of adrenal androgen secretion represents the first line of therapy toward spontaneous conception in both sexes.

Multiple functions of syncytiotrophoblast mitochondria

The human placenta plays a central role in pregnancy, and the syncytiotrophoblast cells are the main components of the placenta that support the relationship between the mother and fetus, in apart through the production of progesterone. In this review, the metabolic processes performed by syncytiotrophoblast mitochondria associated with placental steroidogenesis are described. The metabolism of cholesterol, specifically how this steroid hormone precursor reaches the mitochondria, and its transformation into progesterone are reviewed. The role of nucleotides in steroidogenesis, as well as the mechanisms associated with signal transduction through protein phosphorylation and dephosphorylation of proteins is discussed. Finally, topics that require further research are identified, including the need for new techniques to study the syncytiotrophoblast in situ using non-invasive methods.

Clinical and molecular review of atypical congenital adrenal hyperplasia

Congenital adrenal hyperplasia (CAH) is one of the most common inherited metabolic disorders. It comprises a group of autosomal recessive disorders caused by the mutations in the genes encoding for steroidogenic enzymes that involved cortisol synthesis. More than 90% of cases are caused by a defect in the enzyme 21-hydroxylase. Four other enzyme deficiencies (cholesterol side-chain cleavage, 17α-hydroxylase [P450c17], 11β-hydroxylase [P450c11β], 3β-hydroxysteroid dehydrogenase) in the steroid biosynthesis pathway, along with one cholesterol transport protein defect (steroidogenic acute regulatory protein), and one electrontransfer protein (P450 oxidoreductase) account for the remaining cases. The clinical symptoms of the different forms of CAH result from the particular hormones that are deficient and those that are produced in excess. A characteristic feature of CAH is genital ambiguity or disordered sex development, and most variants are associated with glucocorticoid deficiency. However, in the rare forms of CAH other than 21-hydroxylase deficiency so-called "atypical CAH", the clinical and hormonal phenotypes can be more complicated, and are not well recognized. This review will focus on the atypical forms of CAH, including the genetic analyses, and phenotypic correlates.