Delayed diagnosis of congenital adrenal hyperplasia with salt wasting due to type II 3beta-hydroxysteroid dehydrogenase deficiency

Genetic Testing for a Patient with Suspected 3 Beta-Hydroxysteroid Dehydrogenase Deficiency: A Case of Unreported Genetic Variants

3beta-hydroxysteroid dehydrogenase type II deficiency (HSD3B2 deficiency), a rare form of congenital adrenal hyperplasia (CAH), is characterized by varying degrees of salt loss and incomplete masculinization in males and mild virilization or normal external genitalia in females. We report the case of a patient (46XY) showing salt loss and incomplete masculinization, markedly elevated levels of 17OHP (17 hydroxyprogesterone), ACTH (Adreno Cortico Tropic Hormone), testosterone and delta4androstenedione (delta4A), low levels of cortisol and absence of bone skeletal alterations that frequently characterize POR (Cytochrome P450 oxidoreductase) deficiency. Mutation analysis by Sanger sequencing of the HSD3B2 gene showed that the patient presented with a compound heterozygote for two novel variants c.370A>G p.Ser124Gly and c.308-6 G>A. The two HSD3B2 gene variants were also present in the patient’s older brother showing only incomplete masculinization. The in silico analysis revealed a probable damaging effect of c.370A>G p.Ser124Gly: residue p.Ser124 is highly conserved among species and seems to be located in the catalytic site of the enzyme, playing a pivotal role in NAD(H) binding to its substrate. Intronic c.308-6G>A variant is predicted to be likely pathogenic; the substitution seems to cause a change in the splice acceptor site located 6bp downstream of the variant. The two siblings seem to be affected by 3β-HSD2 deficiency; nevertheless, the two novel variants are likely to cause variable expressivity of the disease.

3β-Hydroxysteroid Dehydrogenase Type 2 (3βHSD2) Deficiency due to a Novel Compound Heterozygosity of a Missense Mutation (p.Thr259Met) and Frameshift Deletion (p.Lys273ArgFs*7) in an Undervirilized Infant Male with Salt Wasting

Deficiency of 3β-hydroxysteroid dehydrogenase type 2 (3βHSD2) is a rare type of congenital adrenal hyperplasia (CAH), causing impaired steroid hormone production in both adrenals and gonads. Phenotype ranges, according to the genetic defect, from the salt-wasting form in both sexes to undervirilization in males and virilization in females. We present a 13-month-old male infant who was admitted to the hospital with signs of adrenocortical insufficiency and genital ambiguity. Clinical presentation, hormonal profile, laboratory evaluation, and karyotype were suggestive of the salt-wasting form of CAH due to 3βHSD2 deficiency. Mutational analysis revealed a missense mutation c.776C>T (p.Thr259Met), inherited by the mother, and a frameshift deletion c.818-819delAA (p.Lys273ArgFs*7), inherited by the father. Both mutations are considered pathogenic. To our knowledge this is the first case of an undervirilized male infant with salt wasting bearing this pathogenic frameshift deletion p.Lys273ArgFs*7 in compound heterozygosity with the missense mutation p.Thr259Met.

Case Report:clinical experience of bilateral giant pediatric Testicular adrenal rest tumors with 3 Beta-Hydroxysteroid Dehydrogenase-2 family history

Background

We reported a patient with Testicular adrenal rest tumors(TARTs) caused by congenital adrenal hyperplasia(CAH). TARTs occur frequently in CAH population with 21-hydroxylase deficiency(21-OHD). There are few reports of TARTs with 3β-hydroxysteroid dehydrogenase deficiency-2 (3β-2HSD).Furthermore,gaint TARTs are rarely mentioned in reported cases involving affected siblings.

Case presentation

A 14-year-old male patient was admitted by congenital adrenal hyperplasia with progressively increasing bilateral testicular masses.The Patient and his elder brother had been performed mutational and chromosome analysis and biopsy. Hormonal and anthropometric measurements were performed during endocrine treatments. We successfully performed surgery and excised two 83mm×46mm×44mm and 74mm×49mm×31mm tumors. Our pathology and immunochemistry tests have proven TARTs in patient. At first, both siblings received regular doses of hydrocortisone and fludrocortisones and tumor size regressed. During the one-year irregular intake due to Covid-19 pandemic, endocrine treatment became insensitive and tumor size slowly increased. The gene analysis reported two novel mutations C.776 C>T and C.674 T>A. The C.776 C>T is from father and has been reported. The C.674 T>A inherited from mother and cannot found in gene library and may related to TARTs.

Conclusions

This case illustrates inadequate hormone therapy could cause tumor enlargement. It is essential to seek for ultrasound examination once suspected scrotal mass occurred.It is necessary to adjust endocrine medicine or adopt surgery in refractory gaint TARTs. And presence of tunica vaginalis cavity may indicate the severity of TARTs in surgery.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-02883-x.

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.

Clinical perspectives in congenital adrenal hyperplasia due to 3β-hydroxysteroid dehydrogenase type 2 deficiency

PURPOSE

3β-hydroxysteroid dehydrogenase type 2 deficiency (3βHSD2D) is a very rare variant of congenital adrenal hyperplasia (CAH) causing less than 0.5% of all CAH. The aim was to review the literature.

METHODS

PubMed was searched for relevant articles.

RESULTS

3βHSD2D is caused by HSD3B2 gene mutations and characterized by impaired steroid synthesis in the gonads and the adrenal glands and subsequent increased dehydroepiandrosterone (DHEA) concentrations. The main hormonal changes observed in patients with 3βHSD2D are elevated ratios of the Δ5-steroids over Δ4-steroids but molecular genetic testing is recommended to confirm the diagnosis. Several deleterious mutations in the HSD3B2 gene have been associated with salt-wasting (SW) crisis in the neonatal period, while missense mutations have been associated with a non-SW phenotype. Boys may have ambiguous genitalia, whereas girls present with mild or no virilization at birth. The existence of non-classic 3βHSD2D is controversial. In an acute SW crisis, the treatment includes prompt rehydration, correction of hypoglycemia, and parenteral hydrocortisone. Similar to other forms of CAH, glucocorticoid and mineralocorticoid replacement is needed for long-term management. In addition, sex hormone replacement therapy may be required if normal progress through puberty is failing. Little is known regarding possible negative long-term consequences of 3βHSD2D and its treatments, e.g., fertility, final height, osteoporosis and fractures, adrenal and testicular tumor risk, and mortality.

CONCLUSION

Knowledge is mainly based on case reports but many long-term outcomes could be presumed to be similar to other types of CAH, mainly 21-hydroxylase deficiency, although in 3βHSD2D it seems to be more difficult to suppress the androgens.

Mutation of HSD3B2 Gene and Fate of Dehydroepiandrosterone

3βHSD2 enzyme is crucial for adrenal and gonad steroid biosynthesis. In enzyme deficiency states, due to recessive loss-of-function HSD3B2 mutations, steroid flux is altered and clinical manifestations result. Deficiency of 3βHSD2 activity in the adrenals precludes normal aldosterone and cortisol synthesis and the alternative backdoor and 11-oxygenated C19 steroid pathways and the flooding of cortisol precursors along the Δ5 pathway with a marked rise in DHEA and DHEAS production. In gonads, it precludes normal T and estrogen synthesis. Here, we review androgen-dependent male differentiation of the external genitalia in humans and link this to female development and steroidogenesis in the developing adrenal cortex. The molecular mechanisms governing postnatal adrenal cortex zonation and ZR development were also revised. This chapter will review relevant clinical, hormonal, and genetic aspects of 3βHSD2 deficiency with emphasis on the significance of alternate fates encountered by steroid hormone precursors in the adrenal gland and gonads. Our current knowledge of the process of steroidogenesis and steroid action is derived from pathological conditions. In humans the 3βHSD2 deficiency represents a model of nature that reinforces our knowledge about the role of the steroidogenic alternative pathway in sex differentiation in both sexes. However, the physiological role of the high serum DHEAS levels in fetal life as well as after adrenarche remains to be elucidated.

Adrenarche unmasks compound heterozygous 3β-hydroxysteroid dehydrogenase deficiency: c.244G>A (p.Ala82Thr) and the novel 931C>T (p.Gln311*) variant in a non-salt wasting, severely undervirilised 46XY

3β-Hydroxysteroid dehydrogenase type II deficiency (3βHSD2) congenital adrenal hyperplasia is a rare cause of ambiguous genitalia, resulting in abnormal virilisation in both 46XY and 46XX. We describe a case of 46XY ambiguous genitalia that was misdiagnosed as androgen insensitivity syndrome. The correct diagnosis was made after adrenarche. Genotyping demonstrated compound heterozygosity in two alleles, the previously described c.244G>A (p.Ala82Thr), and a novel 931C>T(p.Gln311*) variant. We suggest that adrenarche unmasked the condition by driving cortisol production to rates that caused the mutant 3bHSD2 enzyme to become rate limiting for cortisol production. This case illustrates how markedly different the effects of this condition may be on androgen production compared with glucocorticoid and mineralocorticoid production. It also demonstrates how current guidelines based on urinary steroids and cortisol sufficiency may not arrive at the correct diagnosis, and underlines the importance of gene testing in the work-up of disorders of sexual differentiation.

Disorders of sex development: effect of molecular diagnostics

Disorders of sex development (DSDs) are a diverse group of conditions that can be challenging to diagnose accurately using standard phenotypic and biochemical approaches. Obtaining a specific diagnosis can be important for identifying potentially life-threatening associated disorders, as well as providing information to guide parents in deciding on the most appropriate management for their child. Within the past 5 years, advances in molecular methodologies have helped to identify several novel causes of DSDs; molecular tests to aid diagnosis and genetic counselling have now been adopted into clinical practice. Occasionally, genetic profiling of embryos prior to implantation as an adjunct to assisted reproduction, prenatal diagnosis of at-risk pregnancies and confirmatory testing of positive results found during newborn biochemical screening are performed. Of the available genetic tests, the candidate gene approach is the most popular. New high-throughput DNA analysis could enable a genetic diagnosis to be made when the aetiology is unknown or many differential diagnoses are possible. Nonetheless, concerns exist about the use of genetic tests. For instance, a diagnosis is not always possible even using new molecular approaches (which can be worrying for the parents) and incidental information obtained during the test might cause anxiety. Careful selection of the genetic test indicated for each condition remains important for good clinical practice. The purpose of this Review is to describe advances in molecular biological techniques for diagnosing DSDs.

3?-hydroxysteroid dehydrogenase type II deficiency on newborn screening test

3b-hydroxysteroid dehydrogenase II (3β-HSD) deficiency represents a rare CAH variant. Newborns affected with its classic form have salt wasting in early infancy and genital ambiguity in both sexes. High levels of 17-hydroxypregnenolone (Δ517OHP) are characteristic, but extra-adrenal conversion to 17-hydroxyprogesterone (17OHP) may lead to positive results on newborn screening tests. Filter paper 17OHP on newborn screening test was performed by immunofluorometric assay, and serum determinations of 17OHP and Δ517OHP, by radioimmunoassay. A 46,XY infant with genital ambiguity and adrenal crisis at three months of age presented a positive result on newborn screening for CAH. Serum determinations of 17OHP and Δ517OHP were elevated, and a high Δ517OHP/cortisol relation was compatible with the diagnosis of 3β-HSD deficiency. Molecular analysis of the HSD3B2 gene from the affected case revealed the presence of the homozygous p.P222Q mutation, whereas his parents were heterozygous for it. We present the first report of 3β-HSD type II deficiency genotype-proven detected at the Newborn Screening Program in Brazil. The case described herein corroborates the strong genotype-phenotype correlation associated with the HSD3B2 p.P222Q mutation, which leads to a classic salt-wasting 3β-HSD deficiency. Further evaluation of 17OHP assays used in newborn screening tests would aid in determining their reproducibility, as well as the potential significance of moderately elevated 17OHP levels as an early indicator to the diagnosis of other forms of classic CAH, beyond 21-hydroxylase deficiency.

Two novel HSD3B2 missense mutations with diverse residual enzymatic activities for Δ5-steroids

CONTEXT

Classical 3β-hydroxysteroid dehydrogenase (3β-HSD) deficiency (3β-HSDD) is caused by loss-of-function mutations in the HSD3B2 gene encoding type II 3β-HSD, which has a key role in steroid biosynthesis, converting Δ5-steroids to Δ4-steroids in adrenal glands and gonads.

PATIENT

A patient (46, XX) was found to have elevated 17-hydroxyprogesterone (17-OHP) [203 nmol/l (normal range: 2·94 ± 0·9 nmol/l)] by newborn screening. Endocrinological examination revealed dramatically increased Δ5-steroids [e.g. 17-OH pregnenolone: 910 nmol/l (normal range: 12·6 ± 10·5 nmol/l)]. The patient had virilization of external genitalia with labial fusion, suggesting classical 3β-HSDD.

METHODS AND RESULTS

Consistent with the endocrinological data, the patient was a compound heterozygote for two novel missense mutations (p.Y190C and p.S218P) that were identified in HSD3B2. Both Y190 and S218 are conserved among mammals. The mutant proteins had severely impaired residual enzymatic activity in vitro, although both mutants retained higher activity for 17-OH pregnenolone than for the other Δ5-steroids. In a three-dimensional model of the enzyme based on the known structures of similar proteins, both mutations were located extremely close to the predicted substrate-binding pocket. This suggests that the mutations can cause a local conformational change in the substrate-binding pocket, leading to alterations of the binding affinities for Δ5-steroids.

CONCLUSIONS

We identified two novel missense mutations of HSD3B2 that resulted in unbalanced residual enzymatic activities for Δ5-steroids. As a potential novel mechanism, we propose that the mutations, which differently affect the activity towards different substrates, the effects of these mutations provide novel insights into the pathophysiology of 3β-HSDD.

A Case of 3β-Hydroxysteroid Dehydrogenase Type II (HSD3B2) Deficiency Picked up by Neonatal Screening for 21-Hydroxylase Deficiency: Difficulties and Delay in Etiologic Diagnosis

BACKGROUND

3beta-Hydroxysteroid dehydrogenase type II deficiency, a rare form of congenital adrenal hyperplasia, is characterized by varying degrees of salt loss and incomplete masculinization in males and mild virilization or normal external genitalia in females. The clinical signs may be difficult to recognize, increasing the risk of a neonatal adrenal crisis. In addition, elevated 17alpha-hydroxyprogesterone and androstenedione levels due to peripheral HSD3B1 activity may lead to a delay of the correct diagnosis and even to misdiagnosis as CYP21 deficiency.

METHOD

We report a patient who was detected on neonatal screening for 21-hydroxylase deficiency, in part because of cross-reactivity in the commonly used assay.

RESULTS

The diagnostic difficulties in this case were overcome by the use of more specific antibodies.

CONCLUSION

This case emphasizes the importance of confirming the etiological diagnosis with molecular genetic analyses.

Congenital adrenal hyperplasia: focus on the molecular basis of 21-hydroxylase deficiency

Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder caused by defects in one of several steroidogenic enzymes involved in the synthesis of cortisol from cholesterol in the adrenal glands. More than 90% of cases are caused by 21-hydroxylase deficiency, and the severity of the resulting clinical symptoms varies according to the level of 21-hydroxylase activity. 21-Hydroxylase deficiency is usually caused by mutations in theCYP21A2gene, which is located on the RCCX module, a chromosomal region highly prone to genetic recombination events that can result in a wide variety of complex rearrangements, such as gene duplications, gross deletions and gene conversions of variable extensions. Molecular genotyping ofCYP21A2and the RCCX module has proved useful for a more accurate diagnosis of the disease, and prenatal diagnosis. This article summarises the clinical features of 21-hydroxylase deficiency, explains current understanding of the disease at the molecular level, and highlights recent developments, particularly in diagnosis.