A case of early infantile epileptic encephalopathy type 7 with partial response to pyridoxal Phosphate

We present a case of early infantile epileptic encephalopathy type 7 (EIEE7) that partially responded to pyridoxal phosphate (PLP). On the first day. the patient presented with multiple generalized tonic-clonic seizures with eye deviation. Abnormal electroencephalogram (EEG) findings were recorded during the episodes. The patient improved with phenobarbital (PB). but frequent tonic-clonic seizures recurred on day 50. PLP was then introduced, and the seizures ceased within 3 days with EEG results returning to within normal limits. We clinically diagnosed pyridoxine-dependent epilepsy (PDE) in the patient. However, the seizures recurred at 10 months of age. Upon investigation at age 4. plasma and cerebrospinal fluid alpha-aminoadipic scmialdchyde (q-AASA) and pipecolic acid levels were not elevated. Furthermore. ALDH7AI sequencing was normal. PDE was therefore an unlikely diagnosis, and PLP was subsequently stopped. Whole exome sequencing identified a novel heterozygous KCNQ2 frameshift mutation (NM-172107.2:c.2032dup: P. (Glu678Glyfs 187)) when she was 5 years of age. and we then diagnosed EIEE7. Recent reports show that PLP is effective for the treatment of EIEE7. emphasizing that EIEE7 and PDE should be carefully differentiated. It is important to control seizures early for improving the neurodcvelopmenlal prognosis of EIEE7. and it is worth considering early administration of PLP as a second-line drug or treatment concomitant with a voltage-dependent sodium channel inhibitor.