Although missense mutations in the GABA(A) receptor gamma2 subunits (GABRG2) gene have recently been detected in two families with typical absence seizures, no study has been carried out to clarify the relationship between atypical absence and GABA(A) receptors.
Cerebral and portal vein thrombosis, macrocephaly and atypical absence seizures in Glycosylphosphatidyl inositol deficiency due to a PIGM promoter mutation.
The most common semiology is atypical absence seizure, which can be challenging to identify due to comorbid intellectual disability in individuals with SHANK3 mutations; however, no consistent seizure semiology, neuroimaging findings, or EEG findings were present in the majority of individuals with SHANK3 mutations.
This is the first report of P450c17 deficiency presenting in a 46,XY female infant with hypotensive shock, a state exacerbated by the atypical absence of deoxycorticosterone elevation.