J Pediatr Genet 2014; 03(03): 141-145
DOI: 10.3233/PGE-14094
Review Article
Georg Thieme Verlag KG Stuttgart – New York

Pitt-Hopkins syndrome: Mental retardation, psychomotor and developmental delays with facial dysmorphism

Jorge Arturo Avina Fierro
a  Department of Pediatric Dysmorphology, IMSS Western Medical Center, Guadalajara, Mexico
,
Daniel Alejandro Hernández Avina
b  General Hospital Zona 2, IMSS Aguascalientes, Mexico
› Author Affiliations

Subject Editor:
Further Information

Publication History

25 July 2014

10 September 2014

Publication Date:
27 July 2015 (online)

Abstract

The Pitt-Hopkins syndrome is a very rare and severe genetic disease characterized by mental retardation, psychomotor and developmental delays with facial dysmorphism. It was first described in 1978 in patients with mental retardation and crisis of intermittent hyperventilation. The genetic cause is haploinsufficiency of the TCF4 (transcription factor 4) gene that affects the neurodevelopment in both sexes; the majority of patients have spontaneous molecular defects by point mutations or deletions in chromosome 18 at the region 18q21. The syndrome is characterized by neurological abnormalities that affect the motor coordination and balance, in patients with mental and developmental delays. The phenotype includes a peculiar face by specific craniofacial anomalies: prominent square forehead, deep-set eyes with ocular hypertelorism; prominent large nose beaked and broad flat nasal bridge; mouth wide and large, thick fleshy lips, tented bow-shaped upper lip and everted lower lip; cup-shaped ears with dysplastic broad overfolded helix. We review the literature and the photographs of 44 published patients from 2007 to 2012, to resume the principal features of craniofacial anomalies, attempting to delineate the syndrome phenotype and score the specific dysmorphism than help to achieve the early clinical diagnosis.