I-DSD: The First 10 Years.

BACKGROUND: Research and audit are vital for the management of Differences/Disorders of Sex Development (DSD). Clinical networks have a strong potential to drive these activities with the development of care standards including patient experience data and peer-observation of clinical care provision. SUMMARY: Following the 2005 Consensus Workshop that stressed the need for the regular collection and sharing of data across geographical boundaries, the current I-DSD registry was initially launched in 2008. Over a decade later, this registry and its associated network play an increasingly important role in supporting research, training, and benchmarking of care and service. Patient registries can also facilitate the development of local circles of patients and parents with similar conditions who can support each other. KEY MESSAGES: The case for participating in standardized data collection and exchange for DSD has now been made and should be standard practice in centres that care for people with DSD.

A Nationwide Study of the Prevalence and Initial Management of Atypical Genitalia in the Newborn in Scotland.

Provision of optimum healthcare for infants with atypical genitalia requires a clear understanding of the occurrence of this condition. The objective of this study was to determine the prevalence of atypical genitalia and its initial management. A prospective, electronic survey of clinicians within managed clinical networks in Scotland was undertaken between 2013 and 2019. Notification from clinicians was sought for term neonates requiring specialist input for atypical genitalia. Additional information was also sought from the 4 regional genetics laboratories that provided details for neonates who had an urgent karyotype performed for atypical genitalia or sex determination. In total, the study identified 171 term infants who required some investigation for atypical genitalia in the neonatal period, providing a birth prevalence of 1:1,881 term births. Of the 171 infants, 97 (57%) had specialist input over the first 3 months of life, providing a birth prevalence of 1:3,318 term births that received specialist input for atypical genitalia. A total of 92 of these 97 cases had complete 3-month follow-up data, 62 (67%) presented within 24 h of birth, and age at presentation ranged from birth to 28 days. Age at sex assignment ranged from birth to 14 days, and in 63 cases (68%), sex assignment occurred at birth. Thus, the birth prevalence of a case of atypical genitalia where sex assignment was reported to be delayed beyond birth was estimated at 1:11,097 births. In 1 case sex was re-assigned at 3 months. Atypical genitalia requiring specialist input within the first month of life are rare in term newborns, and in only a third of these cases, sex assignment is delayed beyond birth. This study provides new clinical benchmarks for comparing and improving the delivery of care in centres that manage these conditions.

Update on the management of a newborn with a suspected difference of sex development.

Differences or disorders of sex development are a group of heterogeneous conditions, which most commonly present in the newborn period, with the appearance of atypical genitalia on newborn examination. Over recent years, the improvement in our knowledge of these conditions has been accompanied by advances in diagnostic technology and therapeutic options, as well as societal shifts in attitudes and expectations. These factors have placed an even greater emphasis than before on the need for early expert input through a multidisciplinary service that can support the patient and the family; perform and interpret the investigations required to reach a diagnosis; and formulate a management plan that lays down the foundation for optimal long-term outcome. While providing a regional service, the expert team should also be committed to research and quality improvement through participation in national and international networks.

Society for Endocrinology UK Guidance on the initial evaluation of a suspected difference or disorder of sex development (Revised 2021).

It is paramount that any child or adolescent with a suspected difference or disorder of sex development (DSD) is assessed by an experienced clinician with adequate knowledge about the range of conditions associated with DSD and is discussed with the regional DSD service. In most cases, the paediatric endocrinologist within this service acts as the first point of contact but involvement of the regional multidisciplinary service will also ensure prompt access to specialist psychology and nursing care. The underlying pathophysiology of DSD and the process of delineating this should be discussed with the parents and affected young person with all diagnostic tests undertaken in a timely fashion. Finally, for rare conditions such as these, it is imperative that clinical experience is shared through national and international clinical and research collaborations.

Experience of health care at a reference centre as reported by patients and parents of children with rare conditions.

BACKGROUND: Whilst diagnostic pathways for children with rare conditions have shown marked improvement, concerns remain about the care children with rare conditions receive at the level of the health care provider. There is, therefore, a need to improve our understanding of the health care received and explore the development of benchmarks that can be regularly monitored. METHODS: Patients and parents with rare conditions at a tertiary children's hospital were approached to complete a questionnaire-based survey that enquired on their experience of clinical care. The survey explored six key themes: diagnosis; provision of information; availability of support; satisfaction with healthcare team; awareness and support for life-limiting conditions; and participation in research. RESULTS: 130 questionnaires were completed on behalf of 134 patients between 2018 and 2020. Of these, 114 (85%) had received a formal diagnosis, 5 (4%) had a suspected diagnosis and 15 (11%) were undiagnosed. Of the 114 who had received a diagnosis, 24 (20%) were diagnosed within 6 months of developing symptoms, and 22 (20%) within 1-3 years. Seventy patients (53%) reported that they were given little or no information around the time of diagnosis, whilst 81 (63%) felt they were currently well supported, mostly from family members, followed by friends, hospital services, school, other community based healthcare services and lastly, primary care. Of the 127 who were asked, 88 (69%) reported a consistent team of healthcare professionals taking overall responsibility for their care, 86 (67%) felt part of the team, 74 (58%) were satisfied with the level of knowledge of the professionals, and 86 (68%) knew who to contact regarding their condition. Of the 91 who were asked, 23 (25%) were aware their child had a life limiting condition, but only 4 (17%) were receiving specialist support for this. Of 17 who were asked about research, 4 (24%) were actively participating in research, whilst the remainder were all willing to participate in future research. CONCLUSIONS: The survey provides a unique insight into the experience of patients and parents within a specialist centre and the benchmarks that it has revealed can be used for future improvement in services.

Parsing the Heterogeneity of Brain Metabolic Disturbances in Autism Spectrum Disorder.

BACKGROUND: Despite rising prevalence of autism spectrum disorder (ASD), its brain bases remain uncertain. Abnormal levels of N-acetyl compounds, glutamate+glutamine, creatine+phosphocreatine, or choline compounds measured by proton magnetic resonance spectroscopy suggest that neuron or glial density, mitochondrial energetic metabolism, and/or inflammation contribute to ASD neuropathology. The neuroanatomic distribution of these metabolites could help evaluate leading theories of ASD. However, most prior magnetic resonance spectroscopy studies had small samples (all <60, most <20), interrogated only a small fraction of the brain, and avoided assessing effects of age, sex, and IQ. METHODS: We acquired near-whole-brain magnetic resonance spectroscopy of N-acetyl compounds, glutamate+glutamine, creatine+phosphocreatine, and choline compounds in 78 children and adults with ASD and 96 typically developing children and adults, rigorously evaluating effects of diagnosis and severity on metabolites, as moderated by age, sex, and IQ. RESULTS: Effects of ASD and its severity included reduced levels of multiple metabolites in white matter and the perisylvian cortex and elevated levels in the posterior cingulate, consistent with white matter and social-brain theories of ASD. Regionally, both slower and faster decreases of metabolites with age were observed in ASD versus TD. Male-female metabolite differences were widely smaller in ASD than typically developing children and adults. ASD-specific decreases in metabolites with decreasing IQ occurred in several brain areas. CONCLUSIONS: Results support multifocal abnormal neuron or glial density, mitochondrial energetics, or neuroinflammation in ASD, alongside widespread starkly atypical moderating effects of age, sex, and IQ. These findings help parse the neurometabolic signature for ASD by phenotypic heterogeneity.

Birth Weight in Different Etiologies of Disorders of Sex Development.

CONTEXT: It is well established that boys are heavier than girls at birth. Although the cause of birth weight (BW) difference is unknown, it has been proposed that it could be generated from prenatal androgen action. OBJECTIVE: The aim of the current study was to determine the BW of children with disorders of sex development (DSD) of different etiologies and to evaluate the effects of androgen action on BW. METHODS: Data regarding diagnosis, BW, gestational age, karyotype, and concomitant conditions were collected from the International Disorders of Sex Development (I-DSD) Registry (www.i-dsd). BW standard deviation score was calculated according to gestational age. Cases were evaluated according to disorder classification in I-DSD (i.e., disorders of gonadal development, androgen excess, androgen synthesis, androgen action, nonspecific disorder of undermasculinization groups, and Leydig cell defect). RESULTS: A total of 533 cases were available; 400 (75%) cases were 46,XY, and 133 (25%) cases were 46,XX. Eighty cases (15%) were born small for gestational age (SGA). Frequency of SGA was higher in the 46,XY group (17.8%) than in the 46,XX (6.7%) group (P = 0.001). Mean BW standard deviation scores of cases with androgen excess and androgen deficiency [in disorders of gonadal development, androgen synthesis, and Leydig cell defect groups and androgen receptor gene (AR) mutation-positive cases in disorders of androgen action groups] were similar to normal children with the same karyotype. SGA birth frequency was higher in the AR mutation-negative cases in disorders of androgen action group and in the nonspecific disorders of the undermasculinization group. CONCLUSIONS: BW dimorphism is unlikely to be explained by fetal androgen action per se. 46,XY DSDs due to nonspecific disorders of undermasculinization are more frequently associated with fetal growth restriction, SGA, and concomitant conditions.

The pitfalls associated with urinary steroid metabolite ratios in children undergoing investigations for suspected disorders of steroid synthesis.

BACKGROUND: Urinary steroid metabolite ratios may improve the diagnostic yield of potential disorders of steroid hormone synthesis. OBJECTIVES: To investigate the range of ratios and their predictive value in children with suspected disorders of steroid synthesis. DESIGN AND METHODS: Twelve ratios were calculated on steroid metabolite data analysed by gas chromatography-mass spectrometry in urine samples collected between 2008-2010 from 93 children. Urine samples were also analysed in 252 children with no known endocrine concerns. RESULTS: Of the 252 controls, 115 (46%) were male with a median age of 10 yr (range 1 month,18.5 years). Of the 93 cases, 38 (41%) were male with a median age of 6.5 yr (1 day,18.5 yrs). Of these, 41 (44%) had at least one ratio greater than the 95% percentile for controls. The most frequently abnormal ratio, found in 18/93 (19%) cases was (THS/(THE + THF + 5αTHF)) suggestive of 11ß-hydroxylase deficiency. Over this period, 8 (9%) children were subsequently diagnosed with a steroid hormone disorder; 4 with 21-hydroxylase deficiency, 2 with11ß-hydroxylase deficiency and 2 with 5α-reductase deficiency. All except one of these children had at least 1 raised ratio. CONCLUSIONS: Urinary steroid metabolite ratios in suspected disorders of hormone synthesis often exceed the reference range for normal children. The predictive value of steroid metabolite ratios in identifying a genetic abnormality may be condition specific and needs further study to improve its clinical utility.

Advances in neuroimaging.

Over the last 20 years there have been great advances in the field of neuroimaging. However, information is still lacking for patients with a disorder of sex development (DSD) due to the rarity of these conditions. In this chapter the authors will review newly emerging techniques with a focus on the connectivity of the brain, describe sexually dimorphic brain structures and functions, and summarise what is known about the neuroanatomy and neurochemistry of individuals with a DSD. Sexual dimorphism exists in all aspects of neuroanatomy, neurochemistry and neurofunction, but the major challenge is to evaluate the relationship between these differences and relate them to the genetic and hormonal environment of the individual. Further imaging studies of normal gender differences are needed before the implications of neuroimaging findings for individuals with a DSD can be determined. Future directions for study include the association between gender-specific brain connectivity patterns and gender-related differences of various brain diseases.

Changes over time in sex assignment for disorders of sex development.

BACKGROUND AND OBJECTIVE: It is unclear whether the proportion of infants with a disorder of sex development who are raised as male or female has changed over time. The temporal trends in sex assignment of affected cases entered in the International Disorder of Sex Development (I-DSD) Registry were studied. METHODS: Cases of disorders of sex development reported as partial androgen insensitivity syndrome (PAIS; n = 118), disorder of gonadal development (DGD; n = 232), and disorder of androgen synthesis (DAS; n = 104) were divided into those who were born before 1990, 1990-1999, and after 1999. External appearance of the genitalia was described by the external masculinization score. RESULTS: The median (5th-95th percentile) external masculinization scores of those infants with PAIS, DGD, and DAS who were raised as boys were 6 (2-9), 6 (3-9), and 6 (1-12), respectively, and were significantly higher than in those raised as girls (2 [0-6], 2 [0-7], and 0 [0-5], respectively); this difference was maintained in the 3 temporal birth cohorts (P < .01). Of the 118 cases in the pre-1990 cohort, 41 (35%) were raised as boys; of the 148 cases in the 1990-1999 cohort, 60 (41%) were raised as boys; and of the 188 cases in the post-1999 cohort, 128 (68%) were raised as boys. CONCLUSIONS: Although there is an association between the external appearance of the genitalia and the choice of sex assignment, there are clear temporal trends in this practice pointing toward an increased likelihood of affected infants being raised as boys. The impact of this change in practice on long-term health outcomes requires additional focus.

Novel associations in disorders of sex development: findings from the I-DSD Registry.

CONTEXT: The focus of care in disorders of sex development (DSD) is often directed to issues related to sex and gender development. In addition, the molecular etiology remains unclear in the majority of cases. OBJECTIVE: To report the range of associated conditions identified in the international DSD (I-DSD) Registry. DESIGN, SETTING, AND PATIENTS: Anonymized data were extracted from the I-DSD Registry for diagnosis, karyotype, sex of rearing, genetic investigations, and associated anomalies. If necessary, clarification was sought from the reporting clinician. RESULTS: Of 649 accessible cases, associated conditions occurred in 168 (26%); 103 (61%) cases had one condition, 31 (18%) had two conditions, 20 (12%) had three conditions, and 14 (8%) had four or more conditions. Karyotypes with most frequently reported associations included 45,X with 6 of 8 affected cases (75%), 45,X/46,XY with 19 of 42 cases (45%), 46,XY with 112 of 460 cases (24%), and 46,XX with 27 of 121 cases (22%). In the 112 cases of 46,XY DSD, the commonest conditions included small for gestational age in 26 (23%), cardiac anomalies in 22 (20%), and central nervous system disorders in 22 (20%), whereas in the 27 cases of 46,XX DSD, skeletal and renal anomalies were commonest at 12 (44%) and 8 (30%), respectively. Of 170 cases of suspected androgen insensitivity syndrome, 19 (11%) had reported anomalies and 9 of these had confirmed androgen receptor mutations. CONCLUSIONS: Over a quarter of the cases in the I-DSD Registry have an additional condition. These associations can direct investigators toward novel genetic etiology and also highlight the need for more holistic care of the affected person.

Investigation and initial management of ambiguous genitalia.

Infants rarely present with truly ambiguous genitalia and such children should be evaluated by experts who work within a multidisciplinary team that is dedicated for evaluation and management of children and adults with suspected and confirmed disorders of sex development. The paediatric endocrinologist who is a vital and often the central member of this clinical team not only needs to lead the clinical evaluation of the infant systematically but also needs to be sensitive to the needs of the infant, the parents and the rest of the team. A thorough knowledge of the underlying pathophysiology and the strengths and weaknesses of the investigative tools that are available for reaching a diagnosis is crucial.

Detection of cytoplasmic CD antigens within normal human peripheral blood leucocytes.

Polymorphonuclear neutrophils (PMNs) are capable of synthesizing various pro-inflammatory cytokines which may indirectly influence specific immune responses. PMNs may also have the capacity to present foreign peptides to helper T cells (Th cells). In support of this hypothesis, recent studies have shown that neutrophils, when activated by the correct combination of cytokines, can be induced to express cell surface major histocompatibility complex (MHC) Class II (DR) antigen, CD80 (B7.1) and CD86 (B7.2): molecules required for antigen presentation and subsequent T-cell activation. In this study we have used normal "resting" human peripheral blood neutrophils and demonstrated, using a mild fixation and permeabilization protocol, significant cytoplasmic "stores" of these molecules known to be important in antigen presentation. Cytoplasmic MHC Class II antigen was found with two out of 20 normal donors tested whereas cytoplasmic CD80 and CD86 were found to a variable extent within all normal donors. Surprisingly, we also found several other neutrophil cytoplasmic CD antigens more commonly associated with B cells, i.e. CD20, CD21 (CR2/EBV-R) and CD22 (BL-CAM). All of these antigens were confined to the "resting" cell cytoplasm and were never found to be expressed on the cell surface. To exclude the possibility that these antigens were absorbed from plasma and to provide evidence for active synthesis, we used a novel whole blood in situ hybridization flow cytometry assay method to detect mRNA specific for these antigens within normal PMNs. We also conducted real-time polymerase chain reactions to confirm these findings using CD22 as a good example of an "inappropriately expressed" CD antigen. These observations therefore provide support for the hypothesis that human PMNs have the potential to express molecules required for antigen presentation and cell signalling.