Patient 1 is a 5-year-old girl, who was observed to have severe hypotonia in her infancy and developmental delay. She was incapable of lifting her head when she was 7-month-old as well as was incapable of sitting by herself and had trouble imitating speech or actions when she was 1-year-old. By the age of 14 months, she was found to lack the ability to maintain eye contact and displayed head-shaking, hand-clapping and hand-wringing as well as bruxism. While she exhibited purposeful hand use, she presented recurrent, febrile or non-febrile, generalized tonic-clonic seizures at the age of 18 months. After receiving treatment with Levetiracetam (LEV) at 20 months, she achieved seizure-free status at the age of 2 years. At the age of 18 months and 2 years, the findings of her EEG tests revealed spike-and-slow waves with bilateral temporal involvement. Her MRI findings at the age of 14 months indicated a widened subarachnoid space ().
Patient 3 is a female who is currently 4 years 4 months old. She showed some signs of developmental delay, such as lifting her head at the age of 5 months, sitting independently at the age of 9 months, and walking at the age of 2 years; she also did not exhibit any non-verbal communication skills and could not imitate actions or babble. Poor eye contact was observed at the age of 8 months. Hand clapping and hand wringing were observed when she was 1 year 6 months old. She demonstrated purposeful hand use, and at the age of 8 months, she experienced recurrent, febrile or non-febrile, generalized tonic-clonic seizures. She presented with status epilepticus, which later became absence status epilepticus at the age of 3 years 2 months. At this time, she was started on LEV medication but showed no response to it; subsequently, VPA was added to the treatment strategy at the age of 3 years 6 months, and the patient finally achieved a seizure-free status at the age of 4 years. Her EEG tests at the age of 15 months demonstrated sharp-slow synthetical waves at the left central and left parietal-frontal regions. EEG showed generalized sharp-slow waves and MRI findings indicated delayed myelination in the periventricular area at the age of 3 years 2 months ().