To report a rare case of FOXG1 syndrome, often misdiagnosed as cerebral palsy

FOXG1 syndrome is a rare neurodevelopmental disorder caused by variants, deletions or duplications involving the FOXG1 gene. Individuals typically present early in life with failure to achieve milestones, microcephaly, dyskinesias, poor social interaction, and disturbed sleep. Given limited access to genetic testing in the past, individuals often remained undiagnosed. We report the case of a 19 year old female formerly diagnosed with cerebral palsy (CP) who was found to have FOXG1 syndrome.

Our patient was born at term without complications weighing 8 pounds. She was first diagnosed with Peters anomaly due to right ocular lens opacification. In childhood, she diagnosed with CP. She was slow to achieve milestones, remains non-verbal and is unable to sit independently or ambulate. She has feeding difficulties, bouts of agitation, poor sleep and stereotypic hand movements. Exam is notable for prognathism, broad nasal tip, microcephaly and spasticity. She presented with seizures at 18 years of age, partially controlled with levetiracetam. 

MRI brain showed microgyria and white matter atrophy. Micro-array revealed a 1.5 Mb deletion at 14q12 including the FOXG1 and PRKD1 genes.  

FOXG1 gene plays a crucial role in the elaboration and/or function of the forkhead box G1 protein, which is vital for the development of the telencephalon. FOXG1 syndrome is now more commonly diagnosed in early childhood, but adults may remain undiagnosed due to limited access to genetic testing in the past, and the tremendous recent progress in identifying genes associated with intellectual disability. Individuals have often been misdiagnosed as having CP. Neurologists providing care to adults with intellectual disability and are diagnosed as “CP” should consider sending genetic testing which may include microarray, gene panel and/or whole exome sequencing.