Approach to the Infant with a Suspected Disorder of Sex Development

A novel mutation in the AMHR2 gene, resulting in persistent Müllerian duct syndrome presenting with bilateral cryptorchidism and obstructed inguinal hernia

OBJECTIVES

To highlight important clinical aspects of Persistent Müllerian duct syndrome (PMDS). PMDS belongs to the group of differences of sex development. It is attributed to mutations in genes encoding for the anti-Müllerian hormone or its type II receptor (AMHR2) and inherited via an autosomal recessive transmission.

CASE PRESENTATION

An 18-day-old male infant with known bilateral cryptorchidism, presented with left-sided obstructed inguinal hernia. The diagnosis of PMDS was considered during inguinal exploration as both testes together with uterus and fallopian tubes were recognized in the hernial sac. Histology confirmed the presence of Müllerian-derived tissues. Genetic testing revealed two different mutations of the AMHR2 gene, both with autosomal recessive transmission: a frequently encountered deletion of 27 pairs bases on exon 10 of this 11 exon gene and a novel deletion of 2 pairs bases on exon 6.

CONCLUSIONS

This case is notable being the rarest type of PMDS, that of transverse testicular ectopia and associated with a novel AMHR2 gene mutation.

Cohort profile: pathways to care among people with disorders of sex development (DSD)

PURPOSE

The 'DSD Pathways' study was initiated to assess health status and patterns of care among people enrolled in large integrated healthcare systems and diagnosed with conditions comprising the broad category of disorders (differences) of sex development (DSD). The objectives of this communication are to describe methods of cohort ascertainment for two specific DSD conditions-classic congenital adrenal hyperplasia with 46,XX karyotype (46,XX CAH) and complete androgen insensitivity syndrome (CAIS).

PARTICIPANTS

Using electronic health records we developed an algorithm that combined diagnostic codes, clinical notes, laboratory data and pharmacy records to assign each cohort candidate a 'strength-of-evidence' score supporting the diagnosis of interest. A sample of cohort candidates underwent a review of the full medical record to determine the score cutoffs for final cohort validation.

FINDINGS TO DATE

Among 5404 classic 46,XX CAH cohort candidates the strength-of-evidence scores ranged between 0 and 10. Based on sample validation, the eligibility cut-off for full review was set at the strength-of-evidence score of ≥7 among children under the age of 8 years and ≥8 among older cohort candidates. The final validation of all cohort candidates who met the cut-off criteria identified 115 persons with classic 46,XX CAH. The strength-of-evidence scores among 648 CAIS cohort candidates ranged from 2 to 10. There were no confirmed CAIS cases among cohort candidates with scores <6. The in-depth medical record review for candidates with scores ≥6 identified 61 confirmed cases of CAIS.

FUTURE PLANS

As the first cohort of this type, the DSD Pathways study is well-positioned to fill existing knowledge gaps related to management and outcomes in this heterogeneous population. Analyses will examine diagnostic and referral patterns, adherence to care recommendations and physical and mental health morbidities examined through comparisons of DSD and reference populations and analyses of health status across DSD categories.

The radiologist's role in assessing differences of sex development

When infants are identified with a difference of sex development (DSD), a thoughtful approach to imaging is essential to appropriate clinical management. This review provides a comprehensive guide for radiologists who are tasked with performing this critical assignment. We review the embryologic basis of DSDs, with attention to the imaging findings that can indicate specific diagnoses. We also discuss techniques for optimal imaging, including strategies for identifying the gonads by US, tactics for performing genitograms with fluoroscopy and contrast-enhanced US, and the appropriate utilization of MRI. Finally, we review the clinical data and imaging findings that characterize some of the most common DSDs, including congenital adrenal hyperplasia, complete androgen insensitivity syndrome and gonadal dysgenesis.

The laboratory in the multidisciplinary diagnosis of differences or disorders of sex development (DSD): III) Biochemical and genetic markers in the 46,XYIV) Proposals for the differential diagnosis of DSD

Objectives

46,XY differences/disorders of sex development (DSD) involve an abnormal gonadal and/or genital (external and/or internal) development caused by lack or incomplete intrauterine virilization, with or without the presence of Müllerian ducts remnants.

Content

Useful biochemical markers for differential diagnosis of 46,XY DSD include hypothalamic-pituitary-gonadal hormones such as luteinizing and follicle-stimulating hormones (LH and FSH; in baseline or after LHRH stimulation conditions), the anti-Müllerian hormone (AMH), inhibin B, insulin-like 3 (INSL3), adrenal and gonadal steroid hormones (including cortisol, aldosterone, testosterone and their precursors, dihydrotestosterone and estradiol) and the pituitary ACTH hormone. Steroid hormones are measured at baseline or after stimulation with ACTH (adrenal hormones) and/or with HCG (gonadal hormones).

Summary

Different patterns of hormone profiles depend on the etiology and the severity of the underlying disorder and the age of the patient at diagnosis. Molecular diagnosis includes detection of gene dosage or copy number variations, analysis of candidate genes or high-throughput DNA sequencing of panels of candidate genes or the whole exome or genome.

Outlook

Differential diagnosis of 46,XX or 46,XY DSD requires a multidisciplinary approach, including patient history and clinical, morphological, imaging, biochemical and genetic data. We propose a diagnostic algorithm suitable for a newborn with DSD that focuses mainly on biochemical and genetic data.

El laboratorio en el diagnóstico multidisciplinar del desarrollo sexual anómalo o diferente (DSD): III) Marcadores bioquímicos y genéticos en los 46,XY IV) Propuestas para el diagnóstico diferencial de los DSD

Objetivos

El desarrollo sexual anómalo o diferente (DSD) con cariotipo 46,XY incluye anomalías en el desarrollo gonadal y/o genital (externo y/o interno).

Contenido

Los marcadores bioquímicos útiles para el diagnóstico diferencial de los DSD con cariotipo 46,XY incluyen las hormonas del eje hipotálamo-hipófiso gonadal como son las gonadotropinas LH y FSH (en condiciones basales o tras la estimulación con LHRH), la hormona anti-Mülleriana, la inhibina B, el factor insulinoide tipo 3 y las hormonas esteroideas de origen suprarrenal (se incluirá la hormona hipofisaria ACTH) y testicular (cortisol, aldosterona y sus precursores, testosterona y sus precursores, dihidrotestosterona y estradiol). Las hormonas esteroideas se analizarán en condiciones basales o tras la estimulación con ACTH (hormonas adrenales) y/o con HCG (hormonas testiculares). Los patrones de variación de las distintas hormonas dependerán de la causa y la edad de cada paciente. El diagnóstico molecular debe incluir el análisis de un gen candidato, un panel de genes o el análisis de un exoma completo.

Perspectivas

El diagnóstico diferencial de los DSD con cariotipos 46,XX ó 46,XY debe ser multidisciplinar, incluyendo los antecedentes clínicos, morfológicos, de imagen, bioquímicos y genéticos. Se han elaborado numerosos algoritmos diagnósticos.

Genital anomalies in newborns

Examination of genitalia should be an essential part of newborn assessment. Early detection of congenital disorders is essential to begin appropriate medical or surgical therapy and to prevent complications that could profoundly affect a child's life. The present review aims to describe the main genital anomalies in infants and provide images in order to help the physician in current clinical practice.

Differences of sex development in the newborn: from clinical scenario to molecular diagnosis

Differences/disorders of sex development (DSD) are defined as a group of congenital conditions in which the development of chromosomal, gonadal or anatomical sex is atypical. The incidence of DSD is 1:4500 births. The current classification divides DSDs into 3 categories according to chromosomal sex: 46,XX DSD, 46,XY DSD and sex chromosome DSD. DSD phenotypes can be concordant with the genotype (apparently normal external genitalia associated with gonadal dysgenesis), or can range from simply hypospadias to completely masculinised or feminised genitalia with a discordant karyotype. Numerous genes implicated in genital development have been reported. The search of genetic variants represents a central element of the extended investigation, as an improved knowledge of the genetic aetiology helps the immediate and long-term management of children with DSDs, in term of sex of rearing, hormone therapy, surgery, fertility and cancer risk. This review aims to assess the current role of molecular diagnosis in DSD management.

Patients with disorders of sex development

Disorders of sex development (DSDs) are a genetically and clinically heterogeneous group of congenital conditions of the urogenital tract and reproductive system. Time and spatially controlled transcription factors, signal molecules, and an array of different hormones are involved in the development of sex characteristics, and variations in their pathways and actions are associated with DSD. These conditions may be caused by numerical or structural variations in sex chromosomes as well as autosomes, variations in genes involved in gonadal and/or genital development, and changes in gonadal and/or adrenal steroidogenesis. Endogenous or exogenous (maternal) and possibly endocrine disruptors may also interfere with genital development.

The Neonate with Ambiguous Genitalia

Neonates with ambiguous genitalia have various clinical presentations, etiologies, and outcomes, ranging from benign to life-threatening. This review provides a summary of these findings. Some diagnoses may lead to delayed sex assignment. A systematic approach to the evaluation of disorders of sex development can allow for timely treatment and family counseling.

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.

A clinical algorithm to diagnose differences of sex development

The diagnosis and management of children born with ambiguous genitalia is challenging for clinicians. Such differences of sex development (DSDs) are congenital conditions in which chromosomal, gonadal, or anatomical sex is atypical. The aetiology of DSDs is very heterogenous and a precise diagnosis is essential for management of genetic, endocrine, surgical, reproductive, and psychosocial issues. In this Review, we outline a step-by-step approach, compiled in a diagnostic algorithm, for the clinical assessment and molecular diagnosis of a patient with ambiguity of the external genitalia on initial presentation. We appraise established and emerging technologies and their effect on diagnosis, and discuss current controversies.

Diagnostic and therapeutic approach in newborns with ambiguous genitale with disorder of sex development: consensus report of Turkish Neonatal and Pediatric Endocrinology and Diabetes Societies

Disorders of sex development are defined as conditions in which the chromosomal, gonadal, and anatomic sex is discordant. Patients usually present with atypical appearing genitalia. In the assessment of neonates with disorders of sex development, first, it is important to determine whether this situation requires prompt evaluation, and then the karyotype, hormone levels, and underlying etiology should be determined as soon as possible. All these procedures should be performed in the guidance of a multidisciplinary team in reference centers. As the physical examination of the infant is extremely important, the physcian should suspect and then perform a detailed history and physical examinationi and lastly plan the required laboratory and imaging procedures for the definite diagnosis. It is important not to be hurried in the choice of sex. The aim of this article, which includes the diagnostic and therapeutic approaches in infants with ambiguous genitalia, was to provide a common practice for all pediatricians.

Addressing Health Disparities via Coordination of Care and Interprofessional Education: Lesbian, Gay, Bisexual, and Transgender Health and Oral Health Care

Lesbian, gay, bisexual, and transgender (LGBT) persons are a diverse group, but they share a common need for competent, accessible health care, dispensed without intolerance and with an understanding of their unique health needs. Dental practitioners need to understanding that LGBT persons have distinctive health (and oral health) needs. This article reviews the literature on oral and overall health of LGBT persons in the United States, and discusses ways in which dentists can improve the health care they provide to this vulnerable population, including how interprofessional education and collaborative practice may help to reduce oral health disparities within this group.

[Clinical evaluation and management of neonates with disorder of sexual development]

Disorder of sexual development or disorder of sex differentiation (DSD) refers to the inconsistency between karyotype and gonad phenotype and/or gonad anatomy in neonates and is manifested as the difficulty in identifying neonates' sex. According to the karyotype, DSD is classified as 46,XY DSD, 46,XX DSD, and sex chromosome DSD. A combination of detailed medical history, physical examination, and laboratory and imaging examinations is required for the diagnosis and comprehensive assessment of neonatal DSD and the determination of potential causes in clinical practice. Sex identification can only be made after all diagnostic evaluations have been completed. Sex identification of DSD neonates is influenced by various medical and social factors, including genotype (karyotype), sex hormones (levels of testosterone, dihydrotestosterone, and adrenal steroids), sex phenotype (appearance of internal and external genitals), reproduction (fertility potential), feelings of their parents, and even social acceptance and religious customs. A team with multidisciplinary cooperation is required, and patients must be involved in the whole process of sex identification. The major task of neonatal physicians for DSD is to assess the condition of neonates and provide management.

Initial Management of Disorders of Sex Development in Newborns

Disorders of sex development are challenging to evaluate and diagnose in the newborn. As pediatric urologists, our goals are to (1) identify patients who should be evaluated; (2) rule out life-threatening syndromes; and (3) involve a multidisciplinary team for evaluation, diagnosis, and gender assignment. This review briefly goes over the newborn differential diagnosis in disorders of sex development, highlights the important laboratory and imaging data needed, and discusses the multidisciplinary approach to gender assignment and care of these patients. Early involvement of the family in decision-making with the multidisciplinary team is paramount to a timely evaluation and diagnosis in these patients.