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Review
. 2020 Nov;36(11):2635-2640.
doi: 10.1007/s00381-020-04788-z. Epub 2020 Jul 10.

Pai syndrome: a review

Francesca Olivero  1   2 , Thomas Foiadelli  3   4 , Sabino Luzzi  4   5 , Gian Luigi Marseglia  3   4 , Salvatore Savasta  3   4
Affiliations
Review

Pai syndrome: a review

Francesca Olivero et al. Childs Nerv Syst. 2020 Nov.

Abstract

Background: Pai syndrome is a rare idiopathic developmental condition characterized by midline craniofacial abnormalities. It was originally described as the presence of a median cleft lip, cutaneous polyps of the nasal mucosa and face, and midline lipomas of the central nervous system, mostly at the corpus callosum. However, there is great phenotypical variability and these characteristics are rarely all present at once.

Objective: The aim of this review was to analyze the available evidence regarding Pai syndrome in order to better delineate this rare condition and its features.

Methods: We analyzed the PubMed database using the words "Pai syndrome", "frontonasal dysplasia", "cleft lip", "nasal polyp", "facial polyp", and "corpus callosum lipoma", including reviews, case reports and case series.

Conclusion: There is no consensus regarding the diagnostic criteria of Pai syndrome up to date. It is usually diagnosed at birth, and its incidence is often underestimated. At present, the etiology of Pai syndrome is unknown. Several hypotheses regarding its genetic background have been made; however, there are not enough data yet to elucidate this point. An improved awareness could help in diagnosing the condition and performing the necessary investigations. These patients should have a multidisciplinary follow-up.

Keywords: Cleft lip; Corpus callosum lipoma; Facial polyp; Frontonasal dysplasia; Nasal polyp; Pai syndrome.

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Conflict of interest statement

The authors declare that they have no conflict of interest.

Figures

Fig. 1
Fig. 1
Facies of a patient with Pai syndrome [7]
Fig. 2
Fig. 2
CORONAL and SAGITTAL views of brain MRI: lipoma as a thick hyper-intense band and partial agenesis of the corpus callosum [7]
Fig. 3
Fig. 3
Cranial ultrasound in coronal and sagittal views: agenesis of the corpus callosum and a callosal lipoma, appearing as an interhemispheric midline echogenic mass [7]
See this image and copyright information in PMC

References

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Supplementary concepts