Duplication of the hypophysis associated with precocious puberty: presentation of two cases and review of pituitary embryogenesis

The Congenital and Acquired Mechanisms Implicated in the Etiology of Central Precocious Puberty

The etiology of central precocious puberty (CPP) is multiple and heterogeneous, including congenital and acquired causes that can be associated with structural or functional brain alterations. All causes of CPP culminate in the premature pulsatile secretion of hypothalamic GnRH and, consequently, in the premature reactivation of hypothalamic-pituitary-gonadal axis. The activation of excitatory factors or suppression of inhibitory factors during childhood represent the 2 major mechanisms of CPP, revealing a delicate balance of these opposing neuronal pathways. Hypothalamic hamartoma (HH) is the most well-known congenital cause of CPP with central nervous system abnormalities. Several mechanisms by which hamartoma causes CPP have been proposed, including an anatomical connection to the anterior hypothalamus, autonomous neuroendocrine activity in GnRH neurons, trophic factors secreted by HH, and mechanical pressure applied to the hypothalamus. The importance of genetic and/or epigenetic factors in the underlying mechanisms of CPP has grown significantly in the last decade, as demonstrated by the evidence of genetic abnormalities in hypothalamic structural lesions (eg, hamartomas, gliomas), syndromic disorders associated with CPP (Temple, Prader-Willi, Silver-Russell, and Rett syndromes), and isolated CPP from monogenic defects (MKRN3 and DLK1 loss-of-function mutations). Genetic and epigenetic discoveries involving the etiology of CPP have had influence on the diagnosis and familial counseling providing bases for potential prevention of premature sexual development and new treatment targets in the future. Global preventive actions inducing healthy lifestyle habits and less exposure to endocrine-disrupting chemicals during the lifespan are desirable because they are potentially associated with CPP.

MRI Findings of Pituitary Gland in Growth Hormone-Deficient Children and Their Correlation with Growth Hormone Peak during Growth Hormone Stimulation Tests

This study aims to explore the magnetic resonance imaging (MRI) findings of the pituitary gland (PG) in children with growth hormone deficiency (GHD) and their correlation with the growth hormone (GH) peak during clinical GH stimulation tests. Sixty-one children with GHD diagnosed and treated between December 2018 and December 2021 were retrospectively analyzed in terms of clinical and pituitary morphological MRI data. MRI measurements of various diameters of the adenohypophysis (AH) were obtained to analyze the differences of the measured values in different genders and age groups, as well as their relationship with the GH peak in GH stimulation tests. Among the 61 children with GHD, the superior PG margin was protuberant in 2 cases, flat in 13 cases, and concave in 46 cases. The three age groups showed similar pituitary morphology and stalk (P > 0.05). On T1-weighted images, the proportion of isointensity was lower while the proportion of slightly-low signal intensity was higher in the anterior pituitary gland (APG) of children aged >10 compared with those aged 7–10. The comparison of AH linear parameters and GH peak values of male patients among different age groups showed that the anteroposterior (sagittal) diameter of AH and GH peak were the highest in the >10-year-old group and the lowest in the ≤6-year-old group, with those of the 7–10-year-old group in between (P < 0.05). In females, the anteroposterior (sagittal) diameter and GH peak were higher in the 7–10-year-old group and >10-year-old group compared with the ≤6-year-old group (P < 0.05). The MRI coronal and sagittal heights of PG in children with GHD were positively correlated with the GH peak value. In conclusion, in GHD patients, the coronal and sagittal heights as well as the coronal width of AH do not change with sex or age, but the coronal and sagittal heights of PG are positively correlated with the GH peak of GH stimulation tests, which has high application value in the diagnosis of children with GHD.

Duplication of the Pituitary Gland (DPG)-Plus Syndrome Associated With Midline Anomalies and Precocious Puberty: A Case Report and Review of the Literature

Duplication of the pituitary gland (DPG)-plus syndrome is a very rare developmental disorder with few cases described in the literature and characterized by multiple midline and central nervous system malformations. The hypothalamus and hypophysis involvement may be clinically associated with endocrine abnormalities. A 5.9-year-old female child was admitted to our Clinic for premature thelarche and acceleration of growth. DPG-plus syndrome with paired infundibula and pituitary glands was diagnosed after birth, when she appeared small for gestational age and she presented with lingual hypoplasia, cleft palate, right choanal stenosis, nasopharyngeal teratoma, and facial dysmorphisms. Neuroimaging revealed a duplication of the infundibula, the pituitary gland, and the dens of the epistropheus despite surgical removal of a rhino-pharyngeal mass performed at the age of two months. An array-CGH revealed a 2p12 deletion. At our evaluation, bone age assessment resulted advanced and initial pubertal activation was confirmed by Gonadotropin-Releasing Hormone stimulation test. Hormonal suppression treatment was started with satisfactory results. This case shows that DPG-plus syndrome must be considered in presence of midline and craniofacial malformations and endocrinological evaluations should be performed for the prompt and appropriate management of pubertal anomalies.

Duplication of the oral cavity and mandible: a rare congenital craniofacial anomaly

A newborn girl was referred to the otolaryngology service after prenatal imaging showed a right mandibular mass. Physical examination revealed a 1-2 cm mass along the right mandible with the appearance of a vestigial oral cavity. Tissue resembling the vermillion and primitive tongue appeared innervated and moved in conjunction with oral movements. MRI and CT of the mandible after birth confirmed a partially ossified soft tissue mass of the right mandibular body, containing unerupted teeth. She was taken to the operating room at 6 months of age for mass excision and reconstruction. Postoperatively, she healed well and was feeding without difficulty. Craniofacial duplication, including duplication of stomatodeal structures or diprosopus, is a rare condition with a variety of phenotypes. In the case of suspected craniofacial duplication, associated syndromes should be ruled out and appropriate imaging employed to determine the extent of involvement of adjacent structures, which will ultimately guide surgical planning.

Duplication of the pituitary gland and basilar artery, with multiple midline fusion defects and craniofacial anomalies

Duplication of the pituitary gland (DPG) is a phenomenon with no clear syndromic association. This case adds to the literature as a DPG-plus syndrome patient with multiple fusion defects of unknown etiology, fetal risk factors of first trimester tobacco usage and intrauterine drug exposure. An 8-month old female presented with noisy breathing, poor feeding, cleft palate, seizures and failure to thrive. MRI scan revealed duplicate pituitary gland, tubomammillary fusion, absent cleavage of brainstem and superior cerebellar peduncles, and cervical spinal malformations. We performed an airway evaluation, with a glossomandibulopexy for glossoptosis, and a primary palate repair.

Duplication of the pituitary gland - plus syndrome

Duplication of the pituitary gland (DPG) is a very rare developmental anomaly that is often associated with other anomalies – the DPG-plus syndrome and occurs due to splitting of the rostral notochord and prechordal plate during blastogenesis. DPG with the constellation of associated anomalies as in our patient has not been reported previously. This article illustrates the importance of imaging the brain in all patients with obvious midline facial anomalies and the complementary role of MRI and CT in such cases.

Partial craniofacial duplication: a review of the literature and case report

Diprosopus (Greek; di-, "two" + prosopon, "face"), or craniofacial duplication, is a rare craniofacial anomaly referring to the complete duplication of facial structures. Partial craniofacial duplication describes a broad spectrum of congenital anomalies, including duplications of the oral cavity. This paper describes a 15 month-old female with a duplicated oral cavity, mandible, and maxilla. A Tessier type 7 cleft, midline meningocele, and duplicated hypophysis were also present. The preoperative evaluation, surgical approach, postoperative results, and a review of the literature are presented. The surgical approach was designed to preserve facial nerve innervation to the reconstructed cheek and mouth. The duplicated mandible and maxilla were excised and the remaining left maxilla was bone grafted. Soft tissue repair included closure of the Tessier type VII cleft. Craniofacial duplication remains a rare entity that is more common in females. The pathophysiology remains incompletely characterized, but is postulated to be due to duplication of the notochord, as well as duplication of mandibular growth centres. While diprosopus is a severe deformity often associated with anencephaly, patients with partial duplication typically benefit from surgical treatment. Managing craniofacial duplication requires a detailed preoperative evaluation as well as a comprehensive, staged treatment plan. Long-term follow up is needed appropriately to address ongoing craniofacial deformity.

Duplication of the pituitary gland associated with multiple blastogenesis defects: Duplication of the pituitary gland (DPG)-plus syndrome. Case report and review of literature

Background:

Duplication of the pituitary gland (DPG) is a rare craniofacial developmental anomaly occurring during blastogenesis with postulated etiology such as incomplete twinning, teratogens, median cleft face syndrome or splitting of the notochord. The complex craniocaudal spectrum of blastogenesis defects associated with DPG is examined with an illustrative case.

Case Description:

We report for the first time in the medical literature some unique associations with DPG, such as a clival encephalocele, third cerebral peduncle, duplicate odontoid process and a double tongue with independent volitional control. This patient also has the previously reported common associations such as duplicated sella, cleft palate, hypertelorism, callosal agenesis, hypothalamic enlargement, nasopharyngeal teratoma, fenestrated basilar artery and supernumerary teeth. This study also reviews 37 cases of DPG identified through MEDLINE literature search from 1880 to 2011. It provides a detailed analysis of the current case through physical examination and imaging.

Conclusion:

The authors propose that the developmental deformities associated with duplication of pituitary gland (DPG) occur as part of a developmental continuum, not as chance associations. Considering the fact that DPG is uniquely and certainly present throughout the spectrum of these blastogenesis defects, we suggest the term DPG-plus syndrome.

Pituitary duplication with nasopharyngeal teratoma and cleft palate

Pituitary gland duplication is a rare malformation of unknown cause that is often associated with a nasopharyngeal teratoma, among other secondary malformations. This clinical report describes a case of pituitary gland duplication with a nasopharyngeal teratoma, cleft palate, and hypothalamic hamartoma, as well as the surgical management of this patient. This case also raises the question of whether the nasopharyngeal teratoma is the cause of the pituitary duplication above and the cleft palate below or whether it is a result of the primary duplication of the notochordal process. Various theories are presented in an attempt to answer this question, but the exact cause of these malformations remains equivocal. Future research in this topic may elucidate the answer to this question.

Pituitary stalk duplication in association with moya moya disease and bilateral morning glory disc anomaly - broadening the clinical spectrum of midline defects

BACKGROUND

Duplication of the pituitary stalk, morning glory disc anomaly and moya moya are rare malformations. The combination of these findings may be syndromic and may have an underlying genetic etiology.

METHODS

Case report and review of the literature of neurological, ophthalmological, and neuroradiological findings including ophthalmic examination, MRI and MRA.

CASE REPORT

A 2 year-old girl presented with reduced visual acuity and roving eye movements since birth. Ophthalmological workup revealed bilateral morning glory disc anomaly. MRI showed duplication of the pituitary stalk and caudal displacement of the floor of the third ventricle. MRA showed narrowing of the supraclinoid internal carotid arteries with focal narrowing of the proximal middle cerebral arteries consistent with early moya moya disease.

CONCLUSIONS

Review of the literature of pituitary gland duplication and of the combination of morning glory disc anomaly and moya moya disease revealed only one previously reported case. However, the spectrum of this possibly syndromic presentation may be much broader and include various types of anterior midline defects and may have a common underlying genetic cause.