Patient selection: male neonate
No abnormalities may be noted at birth.
Clinical features of the severe neonatal encephalopathy:
(1) microcephaly
(2) hypotonia or hypertonia of extremities (abnormal muscle tone)
(3) involuntary movements (myoclonus, tremors, dystonia)
(4) severe seizures
(5) abnormal breathing (central hypoventilation, respiratory insufficiency, sleep apnea, other)
(6) feeding difficulties during infancy, with variable gastroesophageal reflux
(7) poor head control
This phenotype shows a relentless clinical course. The patient shows severe developmental delay.
CNS abnormalities include:
(1) an abnormal EEG
(2) mild cerebral atrophy
(3) polymicrogyria
Most patients die during infancy or early childhood.
