Pubertal presentation in seven patients with congenital adrenal hyperplasia due to P450 oxidoreductase deficiency

The interpretation of immunometric, chromatographic and mass spectrometric data for steroids in diagnosis of endocrine disorders

The analysis of steroids for endocrine disorders is in transition from immunoassay of individual steroids to more specific chromatographic and mass spectrometric methods with simultaneous determination of several steroids. Gas chromatography (GC) and liquid chromatography (LC) coupled with mass spectrometry (MS) offer unrivalled analytical capability for steroid analysis. These specialist techniques were often judged to be valuable only in a research laboratory but this is no longer the case. In a urinary steroid profile up to 30 steroids are identified with concentrations and excretion rates reported in a number of ways. The assays must accommodate the wide range in steroid concentrations in biological fluids from micromolar for dehydroepiandrosterone sulphate (DHEAS) to picomolar for oestradiol and aldosterone. For plasma concentrations, panels of 5-20 steroids are reported. The profile results are complex and interpretation is a real challenge in order to inform clinicians of likely implications. Although artificial intelligence and machine learning will in time generate reports from the analysis this is a way off being adopted into clinical practice. This review offers guidance on current interpretation of the data from steroid determinations in clinical practice. Using this approach more laboratories can use the techniques to answer clinical questions and offer broader interpretation of the results so that the clinician can understand the conclusion for the steroid defect, and can be advised to program further tests if necessary and instigate treatment. The biochemistry is part of the patient workup and a clinician led multidisciplinary team discussion of the results will be required for challenging patients. The laboratory will have to consider cost implications, bearing in mind that staff costs are the highest component. GC-MS and LC-MS/MS analysis of steroids are the choices. Steroid profiling has enormous potential to improve diagnosis of adrenal disorders and should be adopted in more laboratories in favour of the cheap, non-specific immunological methods.

Rare forms of congenital adrenal hyperplasia

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders due to pathogenic variants in genes encoding enzymes and cofactors involved in adrenal steroidogenesis. Although 21-hydroxylase, 11β-hydroxylase, 3β-hydroxysteroid dehydrogenase type 2, 17α-hydroxylase/17,20-lyase, P450 oxidoreductase, steroidogenic acute regulatory protein, cholesterol side-chain cleavage enzyme deficiencies are considered within the definition of CAH, the term 'CAH' is often used to refer to '21-hydroxylase deficiency (21OHD)' since 21OHD accounts for approximately 95% of CAH in most populations. The prevalence of the rare forms of CAH varies according to ethnicity and geographical location. In most cases, the biochemical fingerprint of impaired steroidogenesis points to the specific subtypes of CAH, and genetic testing is usually required to confirm the diagnosis. Despite there are significant variations in clinical characteristics and management, most data about the rare CAH forms are extrapolated from 21OHD. This review article aims to collate the currently available data about the diagnosis and the management of rare forms of CAH.

Challenges in managing disorders of sex development associated with adrenal dysfunction

INTRODUCTION

Disorders of Sex Development (DSD) associated with adrenal dysfunction occur due to different defects in the proteins involved in gonadal and adrenal steroidogenesis.

AREAS COVERED

The deficiencies in 21-hydroxylase and 11β-hydroxylase lead to DSD in 46,XX patients, defects in StAR, P450scc, 17α-hydroxylase and 17,20-lyase lead to 46,XY DSD, and 3β-HSD2 and POR deficiencies cause both 46,XX and 46,XY DSD. Challenges in diagnosis arise from the low prevalence and the variability in serum steroid profiles. Replacement therapy with hydrocortisone and fludrocortisone helps to minimize life-threatening adrenal crises; however, availability is still an unresolved problem in many countries. Adverse health outcomes, due to the disease or its treatment, are common and include adult short stature, hypertension, osteoporosis, obesity, cardiometabolic risk, and reproductive health issues. Potential biomarkers to improve monitoring and novel treatment options that have been developed with the primary aim to decrease adrenal androgen production are promising tools to help improve the health and quality of life of these patients.

EXPERT OPINION

Steroid profiling by mass spectrometry and next-generation sequencing technologies represent useful tools for establishing an etiologic diagnosis and drive personalized management. Nonetheless, access to health care still remains an issue requiring urgent solutions in many resource-limited settings.

Diagnostic challenges and management advances in cytochrome P450 oxidoreductase deficiency, a rare form of congenital adrenal hyperplasia, with 46, XX karyotype

Cytochrome P450 oxidoreductase deficiency (PORD) is a rare form of congenital adrenal hyperplasia that can manifest with skeletal malformations, ambiguous genitalia, and menstrual disorders caused by cytochrome P450 oxidoreductase (POR) mutations affecting electron transfer to all microsomal cytochrome P450 and some non-P450 enzymes involved in cholesterol, sterol, and drug metabolism. With the advancement of molecular biology and medical genetics, increasing numbers of PORD cases were reported, and the clinical spectrum of PORD was extended with studies on underlying mechanisms of phenotype-genotype correlations and optimum treatment. However, diagnostic challenges and management dilemma still exists because of unawareness of the condition, the overlapping manifestations with other disorders, and no clear guidelines for treatment. Delayed diagnosis and management may result in improper sex assignment, loss of reproductive capacity because of surgical removal of ruptured ovarian macro-cysts, and life-threatening conditions such as airway obstruction and adrenal crisis. The clinical outcomes and prognosis, which are influenced by specific POR mutations, the presence of additional genetic or environmental factors, and management, include early death due to developmental malformations or adrenal crisis, bilateral oophorectomies after spontaneous rupture of ovarian macro-cysts, genital ambiguity, abnormal pubertal development, and nearly normal phenotype with successful pregnancy outcomes by assisted reproduction. Thus, timely diagnosis including prenatal diagnosis with invasive and non-invasive techniques and appropriate management is essential to improve patients' outcomes. However, even in cases with conclusive diagnosis, comprehensive assessment is needed to avoid severe complications, such as chromosomal test to help sex assignment and evaluation of adrenal function to detect partial adrenal insufficiency. In recent years, it has been noted that proper hormone replacement therapy can lead to decrease or resolve of ovarian macro-cysts, and healthy babies can be delivered by in vitro fertilization and frozen embryo transfer following adequate control of multiple hormonal imbalances. Treatment may be complicated with adverse effects on drug metabolism caused by POR mutations. Unique challenges occur in female PORD patients such as ovarian macro-cysts prone to spontaneous rupture, masculinized genitalia without progression after birth, more frequently affected pubertal development, and impaired fertility. Thus, this review focuses only on 46, XX PORD patients to summarize the potential molecular pathogenesis, differential diagnosis of classic and non-classic PORD, and tailoring therapy to maintain health, avoid severe complications, and promote fertility.

Congenital adrenal hyperplasia, disorders of sex development, and infertility in patients with POR gene pathogenic variants: a systematic review of the literature

BACKGROUND

P450 oxidoreductase (POR) deficiency (PORD) is characterized by congenital adrenal hyperplasia (CAH) and disorders of sex development (DSD) in both sexes. PORD can also associate with skeletal defects. However, the prevalence of these phenotypes is unknown.

AIM

To evaluate the prevalence of CAH, DSD, and infertility of patients with POR gene pathogenic variants by a systematic review of the literature.

METHODS

The literature search was performed through PubMed, MEDLINE, Cochrane, Academic One Files, Google Scholar, and Scopus databases. All studies reporting information on CAH, DSD, testicular adrenal rest tumor (TARTs), and fertility in patients with POR gene pathogenic variants were included. Finally, the prevalence of abnormal phenotypes was calculated.

RESULTS

Of the 246 articles initially retrieved, only 48 were included for a total of 119 (46 males and 73 females) patients with PORD. We also included the case of a male patient who consulted us for CAH and TARTs but without DSD. This patient, found to be a carrier of combined heterozygous POR mutation, reached fatherhood spontaneously. All the patients found had CAH. The presence of DSD was found in 65.2%, 82.1%, and 82.1% of patients with compound heterozygosity, homozygosity, or monoallelic heterozygous variants, respectively. The prevalence was significantly higher in females than in males. The prevalence of TARTs in patients with PORD is 2.7%. Only 5 women with PORD became pregnant after assisted reproductive techniques and delivered a healthy baby. Except for the recently reported proband, no other studies focused on male infertility in patients with POR gene variants.

CONCLUSION

This systematic review of the literature reports the prevalence of CAH, DSD, and TARTs in patients with PORD. The unknown prevalence of POR gene pathogenetic variants and the paucity of studies investigating fertility do not allow us to establish whether PORD is associated with infertility. Further studies on both women and men are needed to clarify this relationship.

In Silico Analysis of PORD Mutations on the 3D Structure of P450 Oxidoreductase

Cytochrome P450 oxidoreductase (POR) is a membrane-bound flavoprotein that helps in transferring electrons from its NADPH domain to all cytochrome P450 (CYP450) enzymes. Mutations in the POR gene could severely affect the metabolism of steroid hormones and the development of skeletal muscles, a condition known as Cytochrome P450 oxidoreductase deficiency (PORD). PORD is associated with clinical presentations of disorders of sex development, Antley and Bixler’s syndrome (ABS), as well as an abnormal steroid hormone profile. We have performed an in silico analysis of POR 3D X-ray protein crystal structure to study the effects of reported mutations on the POR enzyme structure. A total of 32 missense mutations were identified, from 170 PORD patients, and mapped on the 3D crystal structure of the POR enzyme. In addition, five of the missense mutations (R457H, A287P, D210G, Y181D and Y607C) were further selected for an in-depth in silico analysis to correlate the observed changes in POR protein structure with the clinical phenotypes observed in PORD patients. Overall, missense mutations found in the binding sites of POR cofactors could lead to a severe form of PORD, emphasizing the importance of POR cofactor binding domains in transferring electrons to the CYP450 enzyme family.

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.

Non-classic cytochrome P450 oxidoreductase deficiency strongly linked with menstrual cycle disorders and female infertility as primary manifestations

STUDY QUESTION

Can cytochrome P450 oxidoreductase deficiency (PORD) be revealed in adult women with menstrual disorders and/or infertility?

SUMMARY ANSWER

PORD was biologically and genetically confirmed in five adult women with chronically elevated serum progesterone (P) who were referred for oligo-/amenorrhea and/or infertility.

WHAT IS KNOWN ALREADY

PORD is an autosomal recessive disease typically diagnosed in neonates and children with ambiguous genitalia and/or skeletal abnormalities. It is responsible for the decreased activity of several P450 enzymes, including CYP21A2, CYP17A1 and CYP19A1, that are involved in adrenal and/or gonadal steroidogenesis. Little is known about the optimal way to investigate and treat patients with adult-onset PORD.

STUDY DESIGN, SIZE, DURATION

In this series, we report five adult females who were evaluated in three tertiary endocrine reproductive departments between March 2015 and September 2018.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Five women aged 19-38 years were referred for unexplained oligo-/amenorrhea and/or infertility. Genetic testing excluded 21-hydroxylase deficiency (21OH-D), initially suspected due to the increased 17-hydroxyprogesterone (17-OHP) levels. Extensive phenotyping, steroid profiling by mass spectrometry, pelvic imaging and next-generation sequencing of 84 genes involved in gonadal and adrenal disorders were performed in all patients. IVF followed by frozen embryo transfer (ET) under glucocorticoid suppression therapy was performed for two patients.

MAIN RESULTS AND THE ROLE OF CHANCE

All patients had oligomenorrhea or amenorrhea. None had hyperandrogenism. Low-normal serum estradiol (E2) and testosterone levels contrasted with chronically increased serum P and 17-OHP levels, which further increased after adrenocorticotrophic hormone (ACTH) administration. Despite excessive P, 17OH-P and 21-deoxycortisol rise after ACTH stimulation suggesting non-classic 21OH-D, CYP21A2 sequencing did not support this hypothesis. Basal serum cortisol levels were low to normal, with inadequate response to ACTH in some women, suggesting partial adrenal insufficiency. All patients harbored rare biallelic POR mutations classified as pathogenic or likely pathogenic according to the American College of Medical Genetics and Genomics standards. Pelvic imaging revealed bilateral ovarian macrocysts in all women. IVF was performed for two women after retrieval of a normal oocyte number despite very low E2 levels during ovarian stimulation. Frozen ET under glucocorticoid suppression therapy led to successful pregnancies.

LIMITATIONS, REASONS FOR CAUTION

The number of patients described here is limited and these data need to be confirmed on a larger number of women with non-classic PORD.

WIDER IMPLICATIONS OF THE FINDINGS

The diagnosis of PORD must be considered in infertile women with chronically elevated P and 17OH-P levels and ovarian macrocysts. Differentiation of this entity from non-classic 21OH-D is important, as the multiple enzyme deficiency requires a specific management. Successful fertility induction is possible by IVF, providing that P levels be sufficiently suppressed by glucocorticoid therapy prior to implantation.

STUDY FUNDING/COMPETING INTEREST(S)

No specific funding was used for this study. There are no potential conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

Clinical, endocrinological, and molecular features of four Korean cases of cytochrome P450 oxidoreductase deficiency

PURPOSE

Cytochrome P450 oxidoreductase (POR) deficiency is a rare autosomal recessive disorder caused by mutations in the POR gene encoding an electron donor for all microsomal P450 enzymes. It is characterized by adrenal insufficiency, ambiguous genitalia, maternal virilization during pregnancy, and skeletal dysplasia. In this study, we investigated the clinical, hormonal, and molecular characteristics of patients with POR deficiency in Korea.

METHODS

This study included four patients with POR deficiency confirmed by biochemical and molecular analysis of POR. Clinical and biochemical findings were reviewed retrospectively. Mutation analysis of POR was performed by Sanger sequencing after polymerase chain reaction amplification of all coding exons and the exon-intron boundaries.

RESULTS

All patients presented with adrenal insufficiency and ambiguous genitalia regardless of their genetic sex. Two patients harbored homozygous p.R457H mutations in POR and presented with adrenal insufficiency and genital ambiguity without skeletal phenotypes. The other two patients with compound heterozygous mutations of c.[1329_1330insC];[1370G>A] (p.[I444Hfs*6];[R457H]) manifested skeletal abnormalities, such as craniosynostosis and radiohumeral synostosis, suggesting Antley-Bixler syndrome. They also had multiple congenital anomalies involving heart, kidney, and hearing ability. All patients were treated with physiologic doses of oral hydrocortisone.

CONCLUSION

We report the cases of 4 patients with POR deficiency identified by mutation analysis of POR. Although the study involved a small number of patients, the POR p.R457H mutation was the most common, suggesting founder effect in Korea. POR deficiency is rare and can be misdiagnosed as 21-hydroxylase or 17α-hydroxylase/17,20-lyase deficiency. Therefore, molecular analysis is critical for confirmatory diagnosis.

P450 Oxidoreductase Deficiency: A Systematic Review and Meta-analysis of Genotypes, Phenotypes, and Their Relationships

CONTEXT

P450 oxidoreductase deficiency (PORD) is a rare genetic disorder that is associated with significant morbidity. However there has been limited analysis of reported PORD cases.

OBJECTIVE

To determine, based on the cohort of reported PORD cases, genotype-phenotype relationships for skeletal malformations, maternal virilisation in pregnancy, adrenal insufficiency, and disorders of sexual development (DSD).

DATA SOURCES

PubMed and Web of Science from January 2004 to February 2018.

STUDY SELECTION

Published case reports/series of patients with PORD. Eligible patients were unique, had biallelic mutations, and their clinical features were reported.

DATA EXTRACTION

Patient data were manually extracted from the text of case reports/series. A malformation score, representing the severity of skeletal malformations, was calculated for each patient.

DATA SYNTHESIS

Of the 211 patients published in the literature, 90 were eligible for inclusion. More than 60 unique mutations were identified in this cohort. Four groups of mutations were identified, through regression modeling, as having significantly different skeletal malformation scores. Maternal virilization in pregnancy, reported for 21% of patients, was most common for R457H mutations. Adrenal insufficiency occurred for the majority of patients (78%) and was typically mild, with homozygous R457H mutations being the least deficient. DSD affected most patients (72%), but were less common for males (46XY) with homozygous R457H mutations.

CONCLUSIONS

PORD is a complex disorder with many possible mutations affecting a large number of enzymes. By analyzing the cohort of reported PORD cases, this study identified clear relationships between genotype and several important phenotypic features.

Congenital Adrenal Hyperplasias Presenting in the Newborn and Young Infant

Congenital adrenal hyperplasia includes autosomal recessive conditions that affect the adrenal cortex steroidogenic enzymes (cholesterol side-chain cleavage enzyme; 3β-hydroxysteroid dehydrogenase; 17α-hydroxylase/17,20 lyase; P450 oxidoreductase; 21-hydroxylase; and 11β-hydroxylase) and proteins (steroidogenic acute regulatory protein). These are located within the three major pathways of the steroidogenic apparatus involved in the production of mineralocorticoids, glucocorticoids, and androgens. Many countries have introduced newborn screening program (NSP) based on 17-OH-progesterone (17-OHP) immunoassays on dried blood spots, which enable faster diagnosis and treatment of the most severe forms of 21-hydroxylase deficiency (21-OHD). However, in several others, the use of this diagnostic tool has not yet been implemented and clinical diagnosis remains challenging, especially for males. Furthermore, less severe classic forms of 21-OHD and other rarer types of CAHs are not identified by NSP. The aim of this mini review is to highlight both the main clinical characteristics and therapeutic options of these conditions, which may be useful for a differential diagnosis in the neonatal period, while contributing to the biochemical evolution taking place in the steroidogenic field. Currently, chromatographic techniques coupled with tandem mass spectrometry are gaining attention due to an increase in the reliability of the test results of NPS for detecting 21-OHD. Furthermore, the possibility of identifying CAH patients that are not affected by 21-OHD but presenting elevated levels of 17-OHP by NSP and the opportunity to include the recently investigated 11-oxygenated androgens in the steroid profiles are promising tools for a more precise diagnosis and monitoring of some of these conditions.

Novel phenotypes and genotypes in Antley-Bixler syndrome caused by cytochrome P450 oxidoreductase deficiency: based on the first cohort of Chinese children

Background

Antley-Bixler syndrome (ABS) caused by P450 oxidoreductase deficiency (PORD) is a congenital adrenal hyperplasia with skeletal malformations and disordered sex development in both sexes. There have been no reports of ABS caused by PORD in Chinese children.

Methods

We described the clinical and genetic characteristics of eight Chinese children with ABS caused by PORD and compared them with those of subjects in previous studies.

Results

Eight patients, aged 6 months–17.8 years, showed strikingly similar craniofacial malformations. We first described four unreported features: lower eyelid fat pads (4/8), prominent lower eyelid-zygoma transverse line (4/8), underdeveloped or absent antihelix (5/8) and single earlobe crease (5/8). Five 46, XY patients presented various degrees of undervirilization, while three 46, XX cases showed masculinization. Basal endocrine measurements revealed the following consistent results: normal cortisol; elevated adrenocorticotropic hormone, progesterone, pregnenolone, 17-hydroxypropgesterone, and corticosterone; and decreased or normal testosterone/oestradiol. We identified three previously reported variants and four novel variants (c.51719_51710delGGCCCCTGTGinsC, p.D210G, p.Y248X and p.R554X) of POR. The most prevalent variant was p.R457H (8/16). The hydrocortisone dosages of patients differed because of variable degrees of adrenal insufficiency.

Conclusions

We described novel phenotypes and genotypes of ABS caused by PORD. The variant p.R457H was the most prevalent in this cohort. All subjects had combined characteristics of 17-hydroxylase and 21-hydroxylase deficiency. Steroid replacement therapy for patients with PORD requires individually tailored dosing.

46,XX DSD due to Androgen Excess in Monogenic Disorders of Steroidogenesis: Genetic, Biochemical, and Clinical Features

The term 'differences of sex development' (DSD) refers to a group of congenital conditions that are associated with atypical development of chromosomal, gonadal, or anatomical sex. Disorders of steroidogenesis comprise autosomal recessive conditions that affect adrenal and gonadal enzymes and are responsible for some conditions of 46,XX DSD where hyperandrogenism interferes with chromosomal and gonadal sex development. Congenital adrenal hyperplasias (CAHs) are disorders of steroidogenesis that mainly involve the adrenals (21-hydroxylase and 11-hydroxylase deficiencies) and sometimes the gonads (3-beta-hydroxysteroidodehydrogenase and P450-oxidoreductase); in contrast, aromatase deficiency mainly involves the steroidogenetic activity of the gonads. This review describes the main genetic, biochemical, and clinical features that apply to the abovementioned conditions. The activities of the steroidogenetic enzymes are modulated by post-translational modifications and cofactors, particularly electron-donating redox partners. The incidences of the rare forms of CAH vary with ethnicity and geography. The elucidation of the precise roles of these enzymes and cofactors has been significantly facilitated by the identification of the genetic bases of rare disorders of steroidogenesis. Understanding steroidogenesis is important to our comprehension of differences in sexual development and other processes that are related to human reproduction and fertility, particularly those that involve androgen excess as consequence of their impairment.

Monogenic Disorders of Adrenal Steroidogenesis

Disorders of adrenal steroidogenesis comprise autosomal recessive conditions affecting steroidogenic enzymes of the adrenal cortex. Those are located within the 3 major branches of the steroidogenic machinery involved in the production of mineralocorticoids, glucocorticoids, and androgens. This mini review describes the principles of adrenal steroidogenesis, including the newly appreciated 11-oxygenated androgen pathway. This is followed by a description of pathophysiology, biochemistry, and clinical implications of steroidogenic disorders, including mutations affecting cholesterol import and steroid synthesis, the latter comprising both mutations affecting steroidogenic enzymes and co-factors required for efficient catalysis. A good understanding of adrenal steroidogenic pathways and their regulation is crucial as the basis for sound management of these disorders, which in the majority present in early childhood.

The evolution of methods for urinary steroid metabolomics in clinical investigations particularly in childhood

The metabolites of cortisol, and the intermediates in the pathways from cholesterol to cortisol and the adrenal sex steroids can be analysed in a single separation of steroids by gas chromatography (GC) coupled to MS to give a urinary steroid profile (USP). Steroids individually and in profile are now commonly measured in plasma by liquid chromatography (LC) coupled with MS/MS. The steroid conjugates in urine can be determined after hydrolysis and derivative formation and for the first time without hydrolysis using GC-MS, GC-MS/MS and liquid chromatography with mass spectrometry (LC-MS/MS). The evolution of the technology, practicalities and clinical applications are examined in this review. The patterns and quantities of steroids changes through childhood. Information can be obtained on production rates, from which children with steroid excess and deficiency states can be recognised when presenting with obesity, adrenarche, adrenal suppression, hypertension, adrenal tumours, intersex condition and early puberty, as examples. Genetic defects in steroid production and action can be detected by abnormalities from the GC-MS of steroids in urine. New mechanisms of steroid synthesis and metabolism have been recognised through steroid profiling. GC with tandem mass spectrometry (GC-MS/MS) has been used for the tentative identification of unknown steroids in urine from newborn infants with congenital adrenal hyperplasia. Suggestions are made as to areas for future research and for future applications of steroid profiling. As routine hospital laboratories become more familiar with the problems of chromatographic and MS analysis they can consider steroid profiling in their test repertoire although with LC-MS/MS of urinary steroids this is unlikely to become a routine test because of the availability, cost and purity of the internal standards and the complexity of data interpretation. Steroid profiling with quantitative analysis by mass spectrometry (MS) after chromatography now provides the most versatile of tests of adrenal function in childhood.

Compound heterozygous variants in POR gene identified by whole-exome sequencing in a Chinese pedigree with cytochrome P450 oxidoreductase deficiency

IMPORTANCE

Cytochrome P450 oxidoreductase deficiency (PORD) is a rare disease exhibiting a variety of clinical manifestations. This condition specifically leads to disordered steroidogenesis, which can affect the development of the reproductive system, skeleton, and other parts of the body. The severe form of PORD is difficult to differentiate with Antley-Bixler syndrome (ABS). The genetic characters and clinical evaluation of PORD are still unclear in China.

OBJECTIVE

To perform an exome analysis and identify the pathogenic cause in order to assist clinicians to obtain a proper evaluation on the genetic condition.

METHODS

The proband underwent detailed physical evaluations. DNA of the proband and his parents was isolated and whole-exome sequencing (WES) was performed. Variants were analyzed and evaluation according to the ACMG guideline.

RESULTS

A 1-year-old Chinese boy with midface hypoplasia, choanal stenosis, multiple joint contractures, micropenis and right cryptorchidism was misdiagnosed with Crouzon syndrome. By trio-whole-exome sequencing, we identified an unreported compound heterozygous mutation (c.667C>T, p.R223* and c.1370G>A, p.R457H) in POR in the proband. This mutation was inherited from healthy heterozygous parents, supporting the diagnosis of PORD, which was further confirmed by biochemical characteristics.

INTERPRETATION

We have identified a pathogenic variant with an unreported compound heterozygous POR mutation, which expands the clinical and genetic spectra of PORD and emphasizes the usefulness of WES for genetic diagnosis.

Congenital adrenal hyperplasia

Congenital adrenal hyperplasia is a group of autosomal recessive disorders encompassing enzyme deficiencies in the adrenal steroidogenesis pathway that lead to impaired cortisol biosynthesis. Depending on the type and severity of steroid block, patients can have various alterations in glucocorticoid, mineralocorticoid, and sex steroid production that require hormone replacement therapy. Presentations vary from neonatal salt wasting and atypical genitalia, to adult presentation of hirsutism and irregular menses. Screening of neonates with elevated 17-hydroxyprogesterone concentrations for classic (severe) 21-hydroxylase deficiency, the most common type of congenital adrenal hyperplasia, is in place in many countries, however cosyntropin stimulation testing might be needed to confirm the diagnosis or establish non-classic (milder) subtypes. Challenges in the treatment of congenital adrenal hyperplasia include avoidance of glucocorticoid overtreatment and control of sex hormone imbalances. Long-term complications include abnormal growth and development, adverse effects on bone and the cardiovascular system, and infertility. Novel treatments aim to reduce glucocorticoid exposure, improve excess hormone control, and mimic physiological hormone patterns.

Congenital Adrenal Hyperplasia

The congenital adrenal hyperplasias comprise a family of autosomal recessive disorders that disrupt adrenal steroidogenesis. The most common form is due to 21-hydroxylase deficiency associated with mutations in the 21-hydroxylase gene, which is located at chromosome 6p21. The clinical features associated with each disorder of adrenal steroidogenesis represent a clinical spectrum that reflect the consequences of the specific mutations. Treatment goals include normal linear growth velocity and "on-time" puberty in affected children. For adolescent and adult women, treatment goals include regularization of menses, prevention of progression of hirsutism, and preservation of fertility. For adolescent and adult men, prevention and early treatment of testicular adrenal rest tumors is beneficial. In this article key aspects regarding pathophysiology, diagnosis, and treatment of congenital adrenal hyperplasia are reviewed.

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.

Cytochrome P450 oxidoreductase deficiency caused by R457H mutation in POR gene in Chinese: case report and literature review

Background

Cytochrome P450 oxidoreductase deficiency (PORD) is a rare disease exhibiting a variety of clinical manifestations. It can be difficult to differentiate with other diseases such as 21-hydroxylase deficiency (21-OHD), polycystic ovary syndrome (PCOS) and Antley–Bixler syndrome (ABS). Nearly 100 cases of PORD have been reported worldwide. However, the genetic characters and clinical management are still unclear, especially in China.

Case presentation

In this study, we report a 27-year-old female Chinese patient who first presented with amenorrhea and recurrence of large ovary cyst. She was misdiagnosed with PCOS and non-classical 21-OHD due to ovary cysts and elevated 17-hydroxy-progesterone. The patient’s complaining of a mild difficulty of bending the metacarpophalangeal joints reminded us to consider PORD, which usually presents with skeletal deformities and sexual dysfunction. The diagnosis of PORD was confirmed by genetic analyses, which showed the patient harboring a homozygous missense mutation in the POR gene (R457H) and her parents carrying the heterozygous mutation. The patient was treated with low-dose corticosteroids and estrogen/progesterone sequential therapy, and her ovarian cyst gradually reduced with regular menstruation in the follow-up. Moreover, the clinical and genetic characteristics of 104 previously reported PORD cases were also summarized and analyzed.

Conclusions

PORD is a very rare disease which can be easily misdiagnosed in mild cases. Clinicians should keep in mind of this disease in patients with sexual dysfunction, especially combined with special skeletal deformities. Our data could provide a consciously understanding of this disease for clinic practicers. Low-dose corticosteroids combined with estrogen/progesterone sequential therapy will be effective in PORD patients with recurrence of large ovary cyst. The fact that the reported PORD patients in China carrying an identical variant R457H in POR gene also give us a viewpoint that R457H mutation in POR gene maybe important in causing PORD in Chinese as same as in Japanese.

P450 Oxidoreductase deficiency: Analysis of mutations and polymorphisms

Cytochrome P450 oxidoreductase (POR) is required for metabolic reactions of steroid and drug metabolizing cytochrome P450 proteins located in endoplasmic reticulum. Mutations in POR cause a complex set of disorders resembling combined deficiencies of multiple steroid metabolizing enzymes. The P450 oxidoreductase deficiency (PORD) was first reported in patients with symptoms of defects in steroidogenic cytochrome P450 enzymes and ambiguous genitalia, and bone malformation features resembling Antley-Bixler syndrome. POR is now classified as a separate and rare form of congenital adrenal hyperplasia (CAH), which may cause disorder of sexual development (DSD). Since the initial description of PORD in 2004, a large number of POR mutations and polymorphisms have been described. In this report we have performed computational analysis of mutations and polymorphisms in POR linked to metabolism of steroids and xenobiotics and pathology of PORD from the reported cases. The mutations in POR that were identified in patients with disruption of steroidogenesis also have severe effects on cytochrome P450 proteins involved in metabolism of drugs. Different variations in POR show a range of diverse effects on different partner proteins that are often linked to the location of the particular variants. The variations in POR that cause defective binding of co-factors always have damaging effects on all partner proteins, while the mutations causing subtle structural changes may lead to altered interaction with partner proteins and the overall effect may be different for each individual partner. Computational analysis of available sequencing data and mutation analysis shows that Japanese (R457H), Caucasian (A287P) and Turkish (399-401) populations can be linked to unique founder mutations. Other mutations identified so far were identified as rare alleles or in single isolated reports. The common polymorphism of POR is the variant A503V which can be found in about 27% of alleles in general population but there are remarkable differences among different sub populations.

Long-term follow-up of a female with congenital adrenal hyperplasia due to P450-oxidoreductase deficiency

P450 oxidoreductase deficiency (PORD) is a variant of congenital adrenal hyperplasia that is caused by POR gene mutations. The POR gene encodes a flavor protein that transfers electrons from nicotinamide adenine dinucleotide phosphate (NADPH) to all microsomal cytochrome P450 type II (including 21-hydroxylase, 17α-hydroxylase 17,20 lyase and aromatase), which is fundamental for their enzymatic activity. POR mutations cause variable impairments in steroidogenic enzyme activities that result in wide phenotypic variability ranging from 46,XX or 46,XY disorders of sexual differentiation, glucocorticoid deficiency, with or without skeletal malformations similar to Antley-Bixler syndrome to asymptomatic newborns diagnosed during neonatal screening test. Little is known about the PORD long-term evolution. We described a 46,XX patient with mild atypical genitalia associated with severe bone malformation, who was diagnosed after 13 years due to sexual infantilism. She developed large ovarian cysts and late onset adrenal insufficiency during follow-up, both of each regressed after hormone replacement therapies. We also described a late surgical approach for the correction of facial hypoplasia in a POR patient.

Fertility Issues in Disorders of Sex Development

Fertility potential should be considered by the multidisciplinary team when addressing gender assignment, surgical management, and patient and family counselling of individuals with disorders of sex development. In 46,XY individuals, defects of gonadal differentiation or androgen or anti-Müllerian hormone synthesis or action result in incomplete or absent masculinization. In severe forms, raised as females, motherhood is possible with oocyte donation if Müllerian ducts have developed. In milder forms, raised as males, azoospermia or oligospermia are frequently found, however paternity has been reported. Most 46,XX patients with normal ovarian organogenesis are raised as females, and fertility might be possible after treatment.

Novel insight into etiology, diagnosis and management of primary adrenal insufficiency

Primary adrenal insufficiency (PAI) is a rare condition in childhood which is either inherited (mostly) or acquired. It is characterized by glucocorticoid and maybe mineralocorticoid deficiency. The most common form in children is 21-hydroxylase deficiency, which belongs to the steroid biosynthetic defects causing PAI. Newer forms of complex defects of steroid biosynthesis are P450 oxidoreductase deficiency and (apparent) cortisone reductase deficiency. Other forms of PAI include metabolic disorders, autoimmune disorders and adrenal dysgenesis, e.g. the IMAGe syndrome, for which the underlying genetic defect has been recently identified. Newer work has also expanded the genetic causes underlying isolated, familial glucocorticoid deficiency (FGD). Mild mutations of CYP11A1 or StAR have been identified in patients with FGD. MCM4 mutations were found in a variant of FGD in an Irish travelling community manifesting with PAI, short stature, microcephaly and recurrent infections. Finally, mutations in genes involved in the detoxification of reactive oxygen species were identified in patients with unsolved FGD. Most mutations were found in the enzyme nicotinamide nucleotide transhydrogenase, which uses the mitochondrial proton pump gradient to produce NADPH. NADPH is essential in maintaining high levels of reduced forms of antioxidant enzymes for the reduction of hydrogen peroxide. Similarly, mutations in the gene for TXNRD2 involved in this system were found in FGD patients, suggesting that the adrenal cortex is particularly susceptible to oxidative stress.

Prenatal diagnosis of congenital adrenal hyperplasia caused by P450 oxidoreductase deficiency

CONTEXT

Mutations in the electron donor enzyme P450 oxidoreductase (POR) result in congenital adrenal hyperplasia with apparent combined 17α-hydroxylase/17,20 lyase and 21-hydroxylase deficiencies, also termed P450 oxidoreductase deficiency (PORD). Major clinical features present in PORD are disordered sex development in affected individuals of both sexes, glucocorticoid deficiency, and multiple skeletal malformations.

OBJECTIVE

The objective of the study was to establish a noninvasive approach to prenatal diagnosis of PORD including assessment of malformation severity to facilitate optimized prenatal diagnosis and timely treatment.

DESIGN

We analyzed 20 pregnancies with children homozygous or compound heterozygous for disease-causing POR mutations and 1 pregnancy with a child carrying a heterozygous POR mutation by recording clinical and biochemical presentations and fetal ultrasound findings. In 4 of the pregnancies (3 homozygous and 1 heterozygous for disease-causing POR mutations), prenatal analysis of steroid metabolite excretion in maternal urine was carried out by gas chromatography/mass spectrometry during gestational weeks 11-23.

RESULTS

Pregnancy complications in our cohort included maternal virilization (6 of 20) with onset in the second trimester. Seven pregnant women presented with low unconjugated estriol at prenatal screening (triple or quadruple antenatal screening test). Overt dysmorphic features were noted in 19 of the 20 babies at birth but observed in only 5 by prenatal ultrasound. These 5 had the most severe malformation phenotypes and poor outcome, whereas the other babies showed normal development. Steroid profiling of maternal urine revealed significantly increased steroids of fetal origin, namely the pregnenolone metabolite epiallopregnanediol and the androgen metabolite androsterone, with concomitant low values for estriol. Diagnostic steroid ratios conclusively indicated PORD as early as gestational week 12. In the heterozygous pregnancy, steroid ratios were only slightly elevated and estriol excretion was normal.

CONCLUSION

Prenatal diagnosis in PORD is readily established via urinary steroid metabolite analysis of maternal urine. Visible malformations at prenatal ultrasound predict a severe malformation phenotype.

NADPH P450 oxidoreductase: structure, function, and pathology of diseases

Cytochrome P450 oxidoreductase (POR) is an enzyme that is essential for multiple metabolic processes, chiefly among them are reactions catalyzed by cytochrome P450 proteins for metabolism of steroid hormones, drugs and xenobiotics. Mutations in POR cause a complex set of disorders that often resemble defects in steroid metabolizing enzymes 17α-hydroxylase, 21-hydroxylase and aromatase. Since our initial reports of POR mutations in 2004, more than 200 different mutations and polymorphisms in POR gene have been identified. Several missense variations in POR have been tested for their effect on activities of multiple steroid and drug metabolizing P450 proteins. Mutations in POR may have variable effects on different P450 partner proteins depending on the location of the mutation. The POR mutations that disrupt the binding of co-factors have negative impact on all partner proteins, while mutations causing subtle structural changes may lead to altered interaction with specific partner proteins and the overall effect may be different for each partner. This review summarizes the recent discoveries related to mutations and polymorphisms in POR and discusses these mutations in the context of historical developments in the discovery and characterization of POR as an electron transfer protein. The review is focused on the structural, enzymatic and clinical implications of the mutations linked to newly identified disorders in humans, now categorized as POR deficiency.

46,XX DSD and Antley-Bixler syndrome due to novel mutations in the cytochrome P450 oxidoreductase gene

Deficiency of the enzyme P450 oxidoreductase is a rare form of congenital adrenal hyperplasia with characteristics of combined and partial impairments in steroidogenic enzyme activities, as P450 oxidoreductase transfers electrons to CYP21A2, CYP17A1, and CYP19A1. It results in disorders of sex development and skeletal malformations similar to Antley-Bixley syndrome. We report the case of a 9-year-old girl who was born with virilized genitalia (Prader stage V), absence of palpable gonads, 46,XX karyotype, and hypergonadotropic hypogonadism. During the first year of life, ovarian cyst, partial adrenal insufficiency, and osteoarticular changes, such as mild craniosynostosis, carpal and tarsal synostosis, and limited forearm pronosupination were observed. Her mother presented severe virilization during pregnancy. The molecular analysis of P450 oxidoreductase gene revealed compound heterozygosis for the nonsense p.Arg223*, and the novel missense p.Met408Lys, inherited from the father and the mother, respectively. Arq Bras Endocrinol Metab. 2012;56(8):578-85

Nonclassic congenital adrenal hyperplasia

PURPOSE OF REVIEW

Late-onset or nonclassic congenital adrenal hyperplasia (NCAH) due to 21-hydroxylase deficiency is one of the most common autosomal recessive disorders. Reported prevalence ranges from 1 in 30 to 1 in 1000. Affected individuals typically present due to signs and symptoms of androgen excess. The purpose of this review is to provide current information regarding the pathophysiology, molecular genetics, and management of this common disorder.

RECENT FINDINGS

Subfertility and the consequences of elevated progesterone concentrations have been increasingly documented for women with NCAH. Although testicular adrenal rest tumors (TARTs) are more common in men with classical congenital adrenal hyperplasia, oligospermia and TARTs have been described in men with NCAH. The phenotypic spectrum of defects in other components of the steroidogenic pathway such as P450 oxidoreductase and steroidogenic acute regulatory protein has been expanded to include milder forms.

SUMMARY

Treatment needs to be directed toward the symptoms. Goals of treatment include normal linear growth velocity, normal rate of skeletal maturation, 'on-time' puberty, regular menstrual cycles, prevention of or limited progression of hirsutism and acne, and fertility. Treatment needs to be individualized and should not be initiated merely to decrease abnormally elevated hormone concentrations.

Genotype-phenotype analysis in congenital adrenal hyperplasia due to P450 oxidoreductase deficiency

CONTEXT

P450 oxidoreductase deficiency (PORD) is a unique congenital adrenal hyperplasia variant that manifests with glucocorticoid deficiency, disordered sex development (DSD), and skeletal malformations. No comprehensive data on genotype-phenotype correlations in Caucasian patients are available.

OBJECTIVE

The objective of the study was to establish genotype-phenotype correlations in a large PORD cohort.

DESIGN

The design of the study was the clinical, biochemical, and genetic assessment including multiplex ligation-dependent probe amplification (MLPA) in 30 PORD patients from 11 countries.

RESULTS

We identified 23 P450 oxidoreductase (POR) mutations (14 novel) including an exonic deletion and a partial duplication detected by MLPA. Only 22% of unrelated patients carried homozygous POR mutations. p.A287P was the most common mutation (43% of unrelated alleles); no other hot spot was identified. Urinary steroid profiling showed characteristic PORD metabolomes with variable impairment of 17α-hydroxylase and 21-hydroxylase. Short cosyntropin testing revealed adrenal insufficiency in 89%. DSD was present in 15 of 18 46,XX and seven of 12 46,XY individuals. Homozygosity for p.A287P was invariably associated with 46,XX DSD but normal genitalia in 46,XY individuals. The majority of patients with mild to moderate skeletal malformations, assessed by a novel scoring system, were compound heterozygous for missense mutations, whereas nearly all patients with severe malformations carried a major loss-of-function defect on one of the affected alleles.

CONCLUSIONS

We report clinical, biochemical, and genetic findings in a large PORD cohort and show that MLPA is a useful addition to POR mutation analysis. Homozygosity for the most frequent mutation in Caucasians, p.A287P, allows for prediction of genital phenotype and moderate malformations. Adrenal insufficiency is frequent, easily overlooked, but readily detected by cosyntropin testing.