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

Abstract

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.

Keywords: Blastogenesis; clival encephalocele; diprosopus; duplication of the pituitary gland; split notochord.

Figure 1

Demonstration of facial abnormalities (a) full body view showing scoliosis, frontal view demonstrating hypertelorism and cleft lip and image of mouth showing supernumerary teeth (b) demonstration of independent movement of double tongues: right tongue withdrawn while left protrudes

Figure 2

T1 weighted MRI with contrast (a) axial image of duplicate pituitary gland (b) coronal image of duplicate pituitary gland (c) coronal image demonstrating two widely spaced pituitary stalks

Figure 3

T1 weighted MRI with contrast of associated cranial abnormalities (a) axial image of midline third cerebral peduncle (b) coronal image demonstrating fenestration of basilar artery, agenesis of corpus callosum

Figure 4

Midline saggital T1 weighted MRI with contrast: defect in the clivus is observed with accompanying encephalocele. Naso-pharyngeal teratoma also observed

Figure 5

Coronal T1 weighted MRI with contrast: odontoid process and vertebral body duplication