Megalencephaly and perisylvian polymicrogyria with postaxial polydactyly and hydrocephalus: a rare brain malformation syndrome associated with mental retardation and seizures
- PMID: 15627943
- DOI: 10.1055/s-2004-830497
Megalencephaly and perisylvian polymicrogyria with postaxial polydactyly and hydrocephalus: a rare brain malformation syndrome associated with mental retardation and seizures
Abstract
Background and objective: Megalencephaly (MEG) or enlarged brain occurs as a mild familial variant with normal brain structure, but otherwise is an uncommon human brain malformation that may be associated with significant developmental and neurological problems. It has been classified into anatomic and metabolic subtypes. The clinical findings associated with anatomic megalencephaly have been variable and few distinct subtypes have been described. We report five unrelated children with severe congenital MEG associated with polymicrogyria (PMG), postaxial polydactyly (POLY) and hydrocephalus (HYD).
Methods: The clinical records and brain MRI of five patients have been reviewed.
Results: All patients had striking MEG that was symmetric in three of the five patients, and mildly asymmetric in two. The birth OFC was between +2 and +4 SD. The gyral pattern was irregular with microgyri typical of PMG, which was most severe in the perisylvian region in all five patients. Four of the five had hydrocephalus treated with a shunt. Subsequently, one of the shunted patients had small ventricles while the others had mildly to moderately enlarged lateral ventricles. Three of the five patients had postaxial polydactyly of all four limbs. The corpus callosum was dysmorphic in one patient with a fused rostrum and genu, and intact although mildly thin in the others. None were abnormally thick. All patients had severe mental retardation; three had seizures and another had an epileptiform EEG.
Conclusion: We believe this constellation of findings (MEG-PMG-POLY-HYD) comprises a new and distinct malformation syndrome that we designate the MPPH syndrome.
Similar articles
-
Megalencephaly and perisylvian polymicrogyria with postaxial polydactyly and hydrocephalus (MPPH): report of a new case.Neuropediatrics. 2007 Aug;38(4):200-3. doi: 10.1055/s-2007-985908. Neuropediatrics. 2007. PMID: 18058629
-
MPPH syndrome: two new cases.Pediatr Neurol. 2011 May;44(5):370-3. doi: 10.1016/j.pediatrneurol.2010.12.009. Pediatr Neurol. 2011. PMID: 21481746
-
A new case of megalencephaly and perisylvian polymicrogyria with post-axial polydactyly and hydrocephalus: MPPH syndrome.Eur J Med Genet. 2006 Nov-Dec;49(6):466-71. doi: 10.1016/j.ejmg.2006.05.001. Epub 2006 Jun 12. Eur J Med Genet. 2006. PMID: 16807158
-
Proximal variants in CCND2 associated with microcephaly, short stature, and developmental delay: A case series and review of inverse brain growth phenotypes.Am J Med Genet A. 2021 Sep;185(9):2719-2738. doi: 10.1002/ajmg.a.62362. Epub 2021 Jun 4. Am J Med Genet A. 2021. PMID: 34087052 Free PMC article. Review.
-
Acromelic frontonasal "dysplasia": further delineation of a subtype with brain malformation and polydactyly (Toriello syndrome).Am J Med Genet. 1992 Jan 15;42(2):180-3. doi: 10.1002/ajmg.1320420209. Am J Med Genet. 1992. PMID: 1733166 Review.
Cited by
-
Syndrome of megalencephaly, polydactyly, and polymicrogyria lacking frank hydrocephalus, with associated MR imaging findings.AJNR Am J Neuroradiol. 2009 Sep;30(8):1620-2. doi: 10.3174/ajnr.A1566. Epub 2009 Apr 15. AJNR Am J Neuroradiol. 2009. PMID: 19369601 Free PMC article.
-
Cerebral cortex expansion and folding: what have we learned?EMBO J. 2016 May 17;35(10):1021-44. doi: 10.15252/embj.201593701. Epub 2016 Apr 7. EMBO J. 2016. PMID: 27056680 Free PMC article. Review.
-
PIK3R2/Pik3r2 Activating Mutations Result in Brain Overgrowth and EEG Changes.Ann Neurol. 2020 Dec;88(6):1077-1094. doi: 10.1002/ana.25890. Epub 2020 Sep 28. Ann Neurol. 2020. PMID: 32856318 Free PMC article.
-
Characterisation of mutations of the phosphoinositide-3-kinase regulatory subunit, PIK3R2, in perisylvian polymicrogyria: a next-generation sequencing study.Lancet Neurol. 2015 Dec;14(12):1182-95. doi: 10.1016/S1474-4422(15)00278-1. Epub 2015 Oct 29. Lancet Neurol. 2015. PMID: 26520804 Free PMC article.
-
Purkinje cells derived from TSC patients display hypoexcitability and synaptic deficits associated with reduced FMRP levels and reversed by rapamycin.Mol Psychiatry. 2018 Nov;23(11):2167-2183. doi: 10.1038/s41380-018-0018-4. Epub 2018 Feb 15. Mol Psychiatry. 2018. PMID: 29449635 Free PMC article.
Publication types
MeSH terms
LinkOut - more resources
Full Text Sources
Medical
Molecular Biology Databases