Cerebral midline developmental anomalies: endocrine,neuroradiographic and ophthalmological features

BACKGROUND: Hypopituitarism may occur in patients with midline cerebral defects (MCD), including septo-optic dysplasia (SOD). HESX1 gene mutations have been associated with SOD. OBJECTIVE: To evaluate the endocrine, ophthalmological and neuroradiographic abnormalities in 18 patients with MCD and SOD without mutations at the HESX1 locus. STUDY DESIGN: The diagnosis of hypothalamic and pituitary abnormalities was confirmed by clinical findings and basal hormone values or functional tests. All patients underwent ophthalmological examination and neuroradiologic studies by MRI. RESULTS: The diagnosis of hypothalamic and pituitary abnormalities varied from 3 days to 13 years. Endocrine abnormalities were found in 88% of the patients: GH deficiency (72%), hypothyroidism (66%), hypogonadism (45%), diabetes insipidus (27%), adrenal insufficiency (10%), and precocious puberty (5%). Psychomotor retardation was observed in 55% and seizures in 22%. Visual status varied from normal to blindness. MRI confirmed heterogeneous intracranial malformations. CONCLUSIONS: Our data support the need for systematic and periodic endocrine evaluation of patients with MCD using a multidisciplinary approach.     

Hypothalamo-pituitary hormone insufficiency associated with cleft lip and palate

Two male patients with congenital cleft lip and palate first seen at ages 10.2 and 21.5 years presented with typical signs of hypothalamic-interior pituitary hormone deficiencies. They were found to lack GH, LH, and FSH and to be partially deficient in TSH and ACTH. Several congenital defects may explain this rare syndrome affecting midline structures in the proximity of the maldeveloped palate, including Rathke's pouch, which migrates distally to develop into the anterior pituitary.     

Septo-optic dysplasia and growth hormone deficiency. De Morsier-syndrome (author's transl)

In a 4 1/2 year old blind boy with cryptorchidism and severe growth retardation a deficiency of growth hormone was verified. He has the symptoms of septo-optic dysplasia, an inborn malformation of the brain with hypoplasia of the optic nerves and tractus opticus, absent septum pellucidum and variable pituitary hormone deficiencies. Treatment with growth hormone was successful. In children with growth hormone deficiency the syndrome seems to be not infrequent.     

Diabetes insipidus with impaired osmotic regulation in septo-optic dysplasia and agenesis of the corpus callosum

The clinical and endocrinological findings in 24 children with septo-optic dysplasia and/or agenesis of the corpus callosum are described with particular reference to posterior pituitary function. Nine had diabetes insipidus. The prevalence of diabetes insipidus was similar in children with complete and incomplete forms of septo-optic dysplasia. Maintenance of normal osmotic balance was very difficult in six of these children, even after the introduction of treatment with vasopressin, either as desmopressin, or lysine vasopressin spray in one of the early cases.     

Combined pituitary hormone deficiency with unique pituitary dysplasia and morning glory syndrome related to a heterozygous PROKR2 mutation

Recent reports have indicated the role of the prokineticin receptor 2 gene (PROKR2) in the etiology of congenital hypopituitarism, including septo-optic dysplasia and Kallmann syndrome. In the present study, using next-generation targeted sequencing, we identified a novel heterozygous PROKR2 variant (c.742C>T; p.R248W) in a female patient who had combined pituitary hormone deficiency (CPHD), morning glory syndrome and a severely malformed pituitary gland. No other mutation was present in 27 genes related to hypogonadotropic hypogonadism, pituitary hormone deficiency and optic nerve malformation. The substituted amino acid was located on the third intracellular loop of the PROKR2 protein, which is a G protein-coupled receptor. Computational analyses with two programs (SIFT and PolyPhen-2) showed that the substitution was deleterious to PROKR2 function. The p.R248W mutation was transmitted from the patient’s mother, who had a slightly delayed menarche. Collectively, we provide further genetic evidence linking heterozygous PROKR2 mutations and the development of CPHD.     

Pituitary dysfunction, morbidity and mortality with congenital midline malformation of the cerebrum

The purpose of this study was to review systematically a series of patients with congenital midline brain defects and pituitary dysfunction in early childhood and to quantitate the degree of dysfunction and clinical outcome. This study was a retrospective analysis of case notes of patients with pituitary dysfunction associated with either a midline cerebral anomaly and/or optic nerve hypoplasia. Forty patients were studied: 2 with semilobar holoprosencephaly, 2 with lobar holoprosencephaly, 18 with septo-optic dysplasia with an intact septum pellucidum, 7 with septo-optic dysplasia with an absent septum pellucidum, 7 with agenesis of the corpus callosum and 4 patients with isolated pituitary hypoplasia. An early age of diagnosis, feeding difficulties, neurodevelopmental disability, visual impairment and seizures were common occurrences. Despite disordered neuro-anatomy, most seizure disorders were caused by hypoglycaemia or hypernatraemia. Hypotensive/hypoglycaemic crises accounted for two out of three deaths within the study population. Most of patients had multiple pituitary hormone deficiency with growth hormone and Adreo corticotrophic hormone deficiency occurring most commonly. Unequivocal isolated hypothalamic dysfunction was an uncommon finding. In congenital midline brain malformation there is a spectrum of disordered neuro-anatomy associated with variable pituitary dysfunction. Clinical manifestations such as convulsions and developmental delay may be due to disordered metabolism and/or neuro-anatomy. Conclusion Children with congenital midline brain defects frequently manifest convulsions, neurodevelopmental disability and poor growth due to disordered metabolism and/or neuro-anatomy. Treating clinicians must be aware of the complex, dynamic neurological and metabolic nature of these patients and their potential for early demise. Received: 9 February 1998 / Accepted in revised form: 29 July 1998     

Diabetes insipidus with impaired osmotic regulation in septo-optic dysplasia and agenesis of the corpus callosum.

The clinical and endocrinological findings in 24 children with septo-optic dysplasia and/or agenesis of the corpus callosum are described with particular reference to posterior pituitary function. Nine had diabetes insipidus. The prevalence of diabetes insipidus was similar in children with complete and incomplete forms of septo-optic dysplasia. Maintenance of normal osmotic balance was very difficult in six of these children, even after the introduction of treatment with vasopressin, either as desmopressin, or lysine vasopressin spray in one of the early cases.     

Sexual precocity in association with septo-optic dysplasia and hypothalamic hypopituitarism.

Sexual precocity in association with abnormalities of the central nervous system is well known, but its occurrence with hypothalamic hypopituitarism is most unusual. We report five females with septo-optic dysplasia, blindness, and multiple pituitary tropic hormone deficiencies: all were growth hormone and adrenocorticotropic hormone deficient; two had diabetes insipidus; one had sexual precocity, and one had early pubertal maturation, whereas three were prepubertal and responded to administration of synthetic gonadotropin-releasing hormone. These children retained ability to secrete gonadotropins despite the presence of anterior hypothalamic disease. Experimental data from primates plus our observations on these patients raise questions about the role of the anterior hypothalamus in gonadotropin secretion in man.     

Pituitary function in a patient with septo-optic dysplasia and pituitary dwarfism (Kaplan-Grumbach-Hoyt syndrome)

The case of a seventeen-year-old female patient with septo-optic dysplasia and pituitary dwarfism is presented. Mental retardation and epilepsy, in addition to absence of the septum pellucidum, point to a widespread lesion of the central nervous system. There is unilateral hypoplasia of the optic nerve. She is of small stature. The dynamic pituitary tests point to deficiency of GH, TSH and ACTH, and an adequate reserve of prolactin, gonadotrophins and vasopressin. TSH insufficiency is probably of primary pituitary origin.     

Evolving hypopituitarism in children with central nervous system lesions

At the time children with suspected hypopituitarism are seen with a subnormal growth rate, it is expected that testing will demonstrate growth hormone (hGH) deficiency. Seven patients with organic CNS lesions--three with histiocytosis X, one with septo-optic dysplasia, one with neonatal meningitis, one with an anterior encephalocele and meningitis, and one with neurofibromatosis who had normal growth hormone concentrations (greater than 7 ng/mL) despite a subnormal growth rate--were studied. Subsequent retesting 0.5 to 4.6 years later demonstrated the development of growth hormone deficiency. Four of the patients had evidence of other pituitary hormone deficiencies at the time of initial testing whereas two subsequently developed other deficiencies. The initial subnormal growth rate in these children may be secondary to their organic CNS lesion or an evolving hypopituitarism, perhaps with deficient somatomedin generation. These studies point out the need for continued observation and retesting in such patients.     

Optic nerve hypoplasia and hypopituitarism

Optic nerve hypoplasia (ONH) has a wide clinical spectrum. When it is associated with absence of the septum pellucidum, it has been termed septo-optic dysplasia. Over the past 50 years, much has been learned about ONH and its association with pituitary endocrinopathies. Causative factors have been sought that may disrupt development of the optic nerve and the hypothalamic-pituitary axis simultaneously. The endocrinological aspects of ONH require lifelong monitoring and replacement of pituitary hormones when necessary. Children with ONH are also at greater risk for structural abnormalities of the brain, and abnormalities in certain structures are positively correlated with increased risk for pituitary deficiencies. However, it has also been shown that children with ONH and "normal" head imaging can still manifest endocrinopathies. Subsequently, a long-term multidisciplinary approach, involving pediatric specialists in ophthalmology, endocrinology, neurology, and behavioral therapy, is critical to optimize growth and development of all children with ONH.     

Evidence for possible Mendelian inheritance of septo-optic dysplasia

We describe two siblings from a highly consanguineous pedigree with absent mid-line brain structures and hypopituitarism. This raises the possibility of a heritable basis for at least some forms of the septo-optic dysplasia sequence.     

The endocrine spectrum of septo-optic dysplasia

Six children with septo-optic dysplasia were evaluated at the Children's Hospital of Philadelphia. There was a common history of young, nulliparous mothers. The clinical presentation of these children differed according to age of presentation and was a function of the degree and type of hypothalamic-pituitary and ophthalmologic impairment. Endocrine evaluation revealed four of six children to be growth hormone deficient, four of six to have hypothalamic hypothyroidism, and two of four to have elevated prolactin levels. One of the patients demonstrated adrenocorticotropic hormone deficiency, and one had diabetes insipidus. Neuroanatomic findings in the children were variable, but, in general, the rare syndrome did not carry as grave a morbidity as had been reported previously. Our data support a high degree of hypothalamic impairment in septo-optic dysplasia.