Background: Rett syndrome is a neurodegenerative disorder with a period of
developmental regression and deceleration of brain growth after a relatively normal
neonatal course. The hallmark of Rett syndrome is repetitive handwringing. The main
criteria include gait abnormalities and stereotypical hand movements (hand wringing
and squeezing, clapping and tapping, hand-to-mouth and object-to-mouth activities,
washing, and rubbing), and losses of acquired purposeful hand skills and of acquired
spoken language. Atypical Rett syndrome, however, meets at least two main criteria. A
magnetic resonance image (MRI) in a Rett syndrome patient is usually not specific. The
genetic causes include MECP2, CDKl5, and FOXG1.
Case Presentation: We have presented a case of atypical Rett syndrome with three
of the four main criteria. Genetic examinations of candidate genes of MeCP2, CDKL5 and
FOXG1 were negative. The brain MRI showed periventricular nodular heterotopia.
Conclusions: We recommend an MRI study when Rett syndrome is suspected.
Abbreviations: OMIM: Online Mendelian Inheritance in Man; EEG: Electroencephalogram; WES: Whole-Exome Sequencing; MRI: Magnetic Resonance Image; ABAS-II: Adaptive Behavior Assessment System®-Second Edition; NCBI ClinVar: National Center for
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