Septo-optic Dysplasia Research Articles

EP112: Septo-optic dysplasia associated with unbalanced chromosome translocation resulting in trisomy 11q13 and monosomy 12q24.3

Distal trisomy 11q syndrome is rare and most often associated with a translocation involving chromosome 22 (Emanuel syndrome). Patients with isolated distal trisomy 11q present with intellectual disability, short stature and microcephaly. Birth defects commonly reported with the syndrome include brain malformations, cardiac defects, diaphragmatic hernia, hip dysplasia, and micrognathia or Pierre-Robin sequence. Distal 12q deletion syndrome is even more rare, and associated with developmental delay and intellectual disability.

Prenatal diagnosis and outcome of fetuses with isolated agenesis of septum pellucidum: cohort study and meta-analysis.

To evaluate the postnatal outcome of children with a prenatal diagnosis of apparently isolated agenesis of the septum pellucidum (ASP). A retrospective cohort study of cases of prenatally diagnosed ASP followed in two tertiary centers and a meta-analysis combining data from the cohort study with data from published studies identified in a systematic review were carried out. Only cases with apparently isolated ASP on antenatal ultrasound and/or magnetic resonance imaging and with available postnatal follow-up data were considered eligible for inclusion. The following outcomes were analyzed: incidence of chromosomal anomalies, agreement between antenatal and postnatal findings, overall incidence of septo-optic dysplasia (SOD) and incidence of major neurological disability (motor, language, coordination or behavioral disorder or epilepsy) in non-SOD children. The incidence of SOD in infants with apparently normal optic pathways on antenatal imaging was also evaluated. Fifteen cases of isolated ASP, with median postnatal follow-up of 36 months (range, 12-60 months), were selected from the two centers. Six previously published studies met the inclusion criteria for the systematic review and a total of 78 cases were eligible for the analysis, including the 15 cases from our series. Genetic tests were carried out antenatally in 30 fetuses, of which two had an abnormal result (pooled proportion, 9.0% (95% CI, 1.8-20.7%); I2 = 0%). Additional or discordant imaging findings were noted postnatally in 9/70 (pooled proportion, 13.7% (95% CI, 3.5-29.0%); I2 = 63.9%) cases. Of all 78 neonates with available follow-up, SOD was diagnosed postnatally in 14 (pooled proportion, 19.4% (95% CI, 8.6-33.2%); I2 = 51.2%). In 60 cases, the optic pathways were considered to be normal on antenatal imaging, and six of these (pooled proportion, 9.1% (95% CI, 1.1-24.0%); I2 = 62.0%) were diagnosed postnatally with SOD. Of the 46 infants with available neurological follow-up who were not affected by SOD, a major neurological disability was diagnosed in three (pooled proportion, 6.5% (95% CI, 0.5-18.6%); I2 = 40.1%). In the vast majority of cases with a prenatal diagnosis of apparently isolated ASP, the prognosis is favorable. However, an additional anomaly is detected after birth in about 14% of cases and has a negative impact on clinical outcome. Detailed antenatal assessment of the brain and optic pathways is strongly recommended in order to identify the presence of associated anomalies. Antenatal visualization of apparently normal optic pathways does not rule out SOD. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Displasia septo-óptica/síndrome de Morsier; una enfermedad que sospechar

Septo-optic dysplasia (SOD) or Morsier syndrome is a rare congenital malformation of infantile neurodevelopment with systemic anatomical and functional involvement. It is characterized by optic nerve hypoplasia, midline brain malformation, and hypothalamic-pituitary axis hypoplasia. The spectrum of clinical manifestations is very wide, from ophthalmological problems to endocrinological disorders that determine the severity and prognosis of these patients. The diagnosis is fundamentally clinical, based on an anamnesis and systematic clinical examination, supported by complementary tests for the study of hormonal deficits and imaging tests that objectify structural malformations. SOD has no cure; however, close follow-up focused on improving comorbidities through hormone replacement, neuropsychological support, and visual correction is necessary to improve the patient’s quality of life. Its low incidence and the breadth of forms of presentation require the knowledge and multidisciplinary approach of specialists in Pediatrics, Neurology, Endocrinology and Ophthalmology, among others. We present a descriptive case of this disease and its management.

Transient central diabetes insipidus after cranioplasty for craniosynostosis in an infant with septo-optic dysplasia.

Transient central diabetes insipidus after cranioplasty for craniosynostosis in an infant with septo-optic dysplasia.

Kallmann Syndrome with Brain Changes and Unilateral Renal Agenesis: A Rare Case Report

Kallmann syndrome (KS) is a rare inherited disorder. It is characterized by hypogonadotropic hypogonadism in association with anosmia or hyposmia, results from defective migration of gonadotropin-releasing hormone producing neurons and olfactory axons. Because KS is a disease due to mutation of genes, patients with KS often display midline head and brain abnormalities such as cleft lip and/or palate and corpus callosum dysgenesis, septo-optic dysplasia, renal agenesis and other phenotypic abnormalities. Here we report a case of 19 years old boy presented with non-development of secondary sex characters, small penis, anosmia and clubfoot. Karyotype was 46XY and hormonal measurement revealed hypogonadotropic hypogonadism. MRI of the brain revealed bilateral agenesis of the olfactory bulb and sulcus, corpus callosal dysgenesis, septo-optic dysplasia and smaller pituitary gland. USG of abdomen revealed right renal agenesis.

AKT Signaling Modifies the Balance between Cell Proliferation and Migration in Neural Crest Cells from Patients Affected with Bosma Arhinia and Microphthalmia Syndrome.

Over the recent years, the SMCHD1 (Structural Maintenance of Chromosome flexible Hinge Domain Containing 1) chromatin-associated factor has triggered increasing interest after the identification of variants in three rare and unrelated diseases, type 2 Facio Scapulo Humeral Dystrophy (FSHD2), Bosma Arhinia and Microphthalmia Syndrome (BAMS), and the more recently isolated hypogonadotrophic hypogonadism (IHH) combined pituitary hormone deficiency (CPHD) and septo-optic dysplasia (SOD). However, it remains unclear why certain mutations lead to a specific muscle defect in FSHD while other are associated with severe congenital anomalies. To gain further insights into the specificity of SMCHD1 variants and identify pathways associated with the BAMS phenotype and related neural crest defects, we derived induced pluripotent stem cells from patients carrying a mutation in this gene. We differentiated these cells in neural crest stem cells and analyzed their transcriptome by RNA-Seq. Besides classical differential expression analyses, we analyzed our data using MOGAMUN, an algorithm allowing the extraction of active modules by integrating differential expression data with biological networks. We found that in BAMS neural crest cells, all subnetworks that are associated with differentially expressed genes converge toward a predominant role for AKT signaling in the control of the cell proliferation–migration balance. Our findings provide further insights into the distinct mechanism by which defects in neural crest migration might contribute to the craniofacial anomalies in BAMS.

Central diabetes insipidus and pain medications \u2013 a risky combination

BackgroundCentral Diabetes Insipidus (CDI) results from decreased production of antidiuretic hormone (ADH) leading to an inability to concentrate urine. CDI is treated with desmopressin (DDAVP). Rarely reported in the literature, opioids and non-steroidal anti-inflammatories (NSAIDs) can induce hyponatremia in individuals treated for CDI.Case presentationA 10-year-old boy with septo-optic dysplasia and CDI was treated with DDAVP 1.6 mg orally TID maintaining normal sodium levels. Post admission for a femur fracture, he was discharged on ibuprofen and hydromorphone. Sodium was 136 mmol/l two days before discharge.He returned to the ED after having a seizure at home. He was euvolemic and mildly lethargic. Sodium was low at 108 mmol/l. DDAVP and hydromorphone were held and he was fluid restricted, but the sodium remained low. Sodium began to rise when Ibuprofen was stopped. Intermittent small doses of DDAVP were given to facilitate gradual correction of hyponatremia. At discharge, sodium had normalized.ConclusionHyponatremia has occasionally been described as a side effect of opioids and rarely of NSAIDs in patients with CDI. Stimulation of the thirst centre may play a role with opioids while a decrease in urine output may be the mechanism with NSAIDs.

The phenotypic spectrum associated with OTX2 mutations in humans.

Objective The transcription factor OTX2is implicated in ocular, craniofacial, and pituitary development.DesignWe aimed to establish the contribution of OTX2 mutations in congenital hypopituitarism patients with/without eye abnormalities, study functional consequences, and establish OTX2 expression in the human brain, with a view to investigate the mechanism of action.MethodsWe screened patients from the UK (n = 103), international centres (n = 24), and Brazil (n = 282); 145 were within the septo-optic dysplasia spectrum, and 264 had no eye phenotype. Transactivation ability of OTX2 variants was analysed in murine hypothalamic GT1-7 neurons. In situ hybridization was performed on human embryonic brain sections. Genetically engineered mice were generated with a series of C-terminal OTX2 variants.ResultsTwo chromosomal deletions and six haploinsufficient mutations were identified in individuals with eye abnormalities; an affected relative of one patient harboured the same mutation without an ocular phenotype. OTX2 truncations led to significant transactivation reduction. A missense variant was identified in another patient without eye abnormalities; however, studies revealed it was most likely not causative. In the mouse, truncations proximal to aa219 caused anophthalmia, while distal truncations and the missense variant were tolerated. During human embryogenesis, OTX2 was expressed in the posterior pituitary, retina, ear, thalamus, choroid plexus, and partially in the hypothalamus, but not in the anterior pituitary.ConclusionsOTX2 mutations are rarely associated with hypopituitarism in isolation without eye abnormalities, and may be variably penetrant, even within the same pedigree. Our data suggest that the endocrine phenotypes in patients with OTX2 mutations are of hypothalamic origin.

SIX3 Variant Causes Pituitary Stalk Interruption Syndrome and Combined Pituitary Hormone Deficiency

The genetic basis for congenital hypopituitarism and related disorders is beginning to emerge, and over 30 causal genes have been identified. Mutations in some of these genes can also cause holoprosencephaly (HPE) or septo-optic dysplasia. SIX3 is a homeodomain protein expressed in the developing brain, pituitary gland, and eye. Heterozygous mutations in SIX3 cause variable HPE in humans and mice. We identified two children with neonatal GH and TSH deficiency and stalk interruption who were doubly heterozygous for rare, likely deleterious variants in SIX3 and POU1F1. Functional studies demonstrated that both variants are disruptive. We used Six3 and Pou1f1 loss of function mice to assess the genetic interaction between Six3 and Pou1f1. Six3 heterozygotes have variable pituitary gland dysmorphology, while Pou1f1 heterozygotes are normal. A significant portion of the Six3+/-; Pou1f1+/dw doubly heterozygous mice have a more pronounced pituitary phenotype than Six3+/-, supporting the possibility of digenic pituitary disease. To understand the role of SIX3 in pituitary and hypothalamic development, we used Prop1-cre and Nkx2.1-cre to delete Six3. Disruption of Six3 expression in Rathke’s pouch caused poor activation of Lhx3 expression and arrested anterior pituitary development. The Nkx2.1-cre, Six3flox/flox embryos had no evidence of infundibulum evagination and failed to induce FGF and BMP signaling, which normally drive expansion of Rathke’s pouch. By E11.5 cells in Rathke’s pouch underwent apoptosis. The Nkx2.1-cre, Six3flox/flox embryos failed to activate expression of Lhx2 and Tbx3 in the neural ectoderm. These embryos had elevated CCND1, MYCN, and Axin2 expression in the area of the presumptive infundibulum. This indicates that SIX3 is necessary to repress cell proliferation and Wnt/beta-catenin signals to promote formation of the pituitary stalk. Thus, Six3 has essential roles in both the neural and oral ectoderm for hypothalamic and pituitary development, respectively. Heterozygous loss of function variants in SIX3 could be a contributor to multiple pituitary hormone deficiencies in children, especially if there are associated craniofacial abnormalities or PSIS.

Novel Pathogenic Variants in LHX3, LHX4 and GLI2 Identified in Pediatric Patients With Congenital Hypopituitarism: From Variant Calling To Variant Testing

Congenital hypopituitarism (CH), septo-optic dysplasia (SOD), and holoprosencephaly (HPE) constitute an important group of structural birth defects that cause significant morbidity and life-long consequences for quality of life and care. The genetic causes are highly overlapping. As such, these disorders can be considered as a spectrum of related disorders. Improved insight into genetic causes would be valuable for patients, families, and medical geneticists. Very few systematic genetic screens have been carried out for patients with CH. We implemented genetic screening using single-molecule molecular inversion probes sequencing to identify causative mutations in a set of 67 genes previously reported in CH patients and the spectrum encompassing SOD and HPE. We captured genomic DNA from 170 Argentinean pediatric patients with CH, and 54% of the patients in this cohort have craniofacial, ophthalmologic, and/or central nervous system defects. We found candidate pathogenic, likely pathogenic and variants uncertain significance (VUS) in 23% of the cases. In order to evaluate the functional consequences of VUS in LHX3, LHX4, and GLI2, we performed in-vitro functional assays to study the activity of the mutated proteins. To test LHX3/4 variants we co-transfected HEK293T cells with wild type (WT) or mutated LHX3/4 variant plasmids and luciferase reporter genes driven by the ɑGSU promoter or GH1 promoter and assayed for luciferase activity. For GLI2 functional analysis we used the cell line NIH/3T3-CG, stably transfected to express GFP under the presence of GLI2 activated form. Endogenous Gli2 was knocked out by CRISPR-Cas9 and clones were selected for absence of GFP expression upon activation of the sonic hedgehog pathway. We tested the ability of transfected WT or mutated GLI2 expression plasmids to restore GFP fluorescence. We concluded that variants LHX3:p.Pro187Ser LHX4:p.Arg84His, p.Gln100His and p.Trp204Leu and GLI2:p.1404Lfs impair activation of the reporter gene, while the LHX3:p.Leu220Met and GLI2:p.L761P have WT activity on their respective assays. Identification of disease-causing variants in CH is complicated by phenotypic variation, incomplete penetrance, and VUS. Functional testing of potentially pathogenic variants is critical to arrive at a definitive molecular diagnosis. A full catalogue of variant effects in known causative genes would be invaluable for clinicians in order to simplify the interpretation of novel variants and reduce the diagnostic odyssey that families often experience.

EP226 - Septo-optic dysplasia in a patient with CDK13-related disorder

eP226 - Septo-optic dysplasia in a patient with CDK13-related disorder

Activating\xa0mutations in BRAF\xa0disrupt the hypothalamo-pituitary axis leading to hypopituitarism in mice and humans

Germline mutations in BRAF and other components of the MAPK pathway are associated with the congenital syndromes collectively known as RASopathies. Here, we report the association of Septo-Optic Dysplasia (SOD) including hypopituitarism and Cardio-Facio-Cutaneous (CFC) syndrome in patients harbouring mutations in BRAF. Phosphoproteomic analyses demonstrate that these genetic variants are gain-of-function mutations leading to activation of the MAPK pathway. Activation of the MAPK pathway by conditional expression of the BrafV600E/+ allele, or the knock-in BrafQ241R/+ allele (corresponding to the most frequent human CFC-causing mutation, BRAF p.Q257R), leads to abnormal cell lineage determination and terminal differentiation of hormone-producing cells, causing hypopituitarism. Expression of the BrafV600E/+ allele in embryonic pituitary progenitors leads to an increased expression of cell cycle inhibitors, cell growth arrest and apoptosis, but not tumour formation. Our findings show a critical role of BRAF in hypothalamo-pituitary-axis development both in mouse and human and implicate mutations found in RASopathies as a cause of endocrine deficiencies in humans.

Chapter 5 - Septo-optic dysplasia

Septo-optic dysplasia (SOD) or de Morsier's syndrome is a rare congenital disorder characterized by a classic triad of: (a) optic nerve hypoplasia, (b) agenesis of septum pellucidum and corpus callosum, and (c) hypoplasia of the hypothalamic-pituitary axis. This chapter will outline the key information regarding the etiology and epidemiology of this syndrome with a focus on its comprehensive management. Particular attention will be paid to the diagnostic stage and the most relevant differential diagnosis, before moving to the complexities of its treatment. In fact, although SOD is not curable, many aspects of this syndrome can be improved through a tailored multidisciplinary approach consisting in hormonal replacement, corrective ophthalmological surgery, management of epileptic seizures, and active neuropsychological support.

Caring for children with septo-optic dysplasia

Caring for children with septo-optic dysplasia

Endocrine Dysfunction in Children with Zika-Related Microcephaly Who Were Born during the 2015 Epidemic in the State of Pernambuco, Brazil.

Congenital viral infections and the occurrence of septo-optic dysplasia, which is a combination of optic nerve hypoplasia, abnormal formation of structures along the midline of the brain, and pituitary hypofunction, support the biological plausibility of endocrine dysfunction in Zika-related microcephaly. In this case series we ascertained the presence and describe endocrine dysfunction in 30 children with severe Zika-related microcephaly from the MERG Pediatric Cohort, referred for endocrinological evaluation between February and August 2019. Of the 30 children, 97% had severe microcephaly. The average age at the endocrinological consultation was 41 months and 53% were female. The most frequently observed endocrine dysfunctions comprised short stature, hypothyroidism, obesity and variants early puberty. These dysfunctions occurred alone 57% or in combination 43%. We found optic nerve hypoplasia (6/21) and corpus callosum hypoplasia (20/21). Seizure crises were reported in 86% of the children. The most common—and clinically important—endocrine dysfunctions were pubertal dysfunctions, thyroid disease, growth impairment, and obesity. These dysfunctions require careful monitoring and signal the need for endocrinological evaluation in children with Zika-related microcephaly, in order to make early diagnoses and implement appropriate treatment when necessary.

Laporan Kasus : Septo Optic Dysplasia (de Morsier Syndrome)

Septo optic dysplasia (SOD) adalah kelainan kongenital yang jarang ditemukan, dengan angka kejadian 1 : 10.000 kelahiran hidup. Karakteristik SOD adalah ditemukannya dua dari tiga kelainan berupa disgenesis septum struktur midline otak, disgenesis saraf optikus, dan disfungsi kelenjar pituitari. Kami melaporkan seorang pasien perempuan berusia 11 tahun datang dengan keluhan mata juling dan gangguan penglihatan. Pada pemeriksaan mata, didapatkan visus mata kanan 1/60 dan mata kiri 6/6. CT scan menunjukan hipoplasia selubung saraf optikus kanan dan agenesis septum pelusidum. Pada pasien tidak terdapat gangguan pertumbuhan ataupun perkembangan serta tidak terdapat gangguan neurologi. Pemeriksaan radiologis memiliki peranan yang penting dalam membantu menegakkan diagnosis SOD karena baik untuk mengevaluasi struktur otak dan saraf optikus

Caring for children with septo-optic dysplasia

Nurses involved in the care of children may encounter this brain disorder, which occurs in 1 out of 10,000 live births.

Developmental Genes and Malformations in the Hypothalamus.

The hypothalamus is a heterogeneous rostral forebrain region that regulates physiological processes essential for survival, energy metabolism, and reproduction, mainly mediated by the pituitary gland. In the updated prosomeric model, the hypothalamus represents the rostralmost forebrain, composed of two segmental regions (terminal and peduncular hypothalamus), which extend respectively into the non-evaginated preoptic telencephalon and the evaginated pallio-subpallial telencephalon. Complex genetic cascades of transcription factors and signaling molecules rule their development. Alterations of some of these molecular mechanisms acting during forebrain development are associated with more or less severe hypothalamic and pituitary dysfunctions, which may be associated with brain malformations such as holoprosencephaly or septo-optic dysplasia. Studies on transgenic mice with mutated genes encoding critical transcription factors implicated in hypothalamic-pituitary development are contributing to understanding the high clinical complexity of these pathologies. In this review article, we will analyze first the complex molecular genoarchitecture of the hypothalamus resulting from the activity of previous morphogenetic signaling centers and secondly some malformations related to alterations in genes implicated in the development of the hypothalamus.

Absent Cavum Septi Pellucidi

Absent Cavum Septi Pellucidi

Multiple Endocrine Deficiencies are Common in Hypoparathyroidism–Retardation–Dysmorphism Syndrome

The rare hypoparathyroidism-retardation-dysmorphism (HRD) syndrome (OMIM #241410) is caused by the mutated tubulin chaperone E (TBCE) gene. This gene encodes a critical protein in the microtubule assembly pathway. To evaluate the endocrine profile of patients with HRD. The study used a retrospective analysis of a large cohort of patients in a single university medical center. Sixty-three patients were diagnosed with HRD during 1990 to 2019; 58 of them had an endocrine evaluation. We investigated somatic growth parameters, the prevalence of hypoglycemia, growth hormone deficiency, hypothyroidism, hypogonadism, and cortisol deficiency. All patients were born small for gestational age, and severe growth retardation was found in all patients with mean height standard deviation score (SDS) of -8.8 (range: -5.1 to -15.1) and weight SDS -18 (range: -5.1 to -61.2). Serum insulin-like growth factor-1 concentrations were very low among the 21 studied patients: -2.32 SDS (range: -0.6 to -2.7). Four out of 14 (28%) investigated patients had growth hormone deficiency, and 55% of patients were hospitalized due to symptomatic hypoglycemia. Adrenal glucocorticoid insufficiency was diagnosed in 22% of those tested. Hypothyroidism was found in 36% of patients. Both hypogonadotrophic and hypergonadotrophic hypogonadism were observed. The main magnetic resonance imaging findings were small anterior pituitary gland, small hippocampus, brain atrophy, thin corpus callosum, Chiari type I malformation, and septo-optic dysplasia. Multiple endocrine abnormalities are common in patients with HRD syndrome. Periodic screening of thyroid and adrenal functions is recommended.