[P2-62] CDKL5 Encephalopathy: Report of 2 Chinese Patients and Literature Review
The X-linked CDKL5 gene, which encodes the cyclin-dependent kinase-like 5 protein, is found to be associated with early-onset epileptic encephalopathy. The kinase involves in brain development and neuronal maturation, but its specific effect is still unknown. Individuals with CDKL5 mutations present with early-onset intractable epilepsy particularly within 3 months of life, severe neurodevelopment delay, and Rett-like features. Here we present two cases with mutations of CDKL5 and stress the role of second-generation sequencing in the etiological identification of early-onset epileptic encephalopathy. Both patients were female infants. One girl got her first seizure at 3 months with up-gazing, rhythmic clonus of limbs for40 seconds. Later she got attacks in clusters with up-gazing, stiffing of limbs for seconds. The other girl had her first seizure at 2 months with up-gazing, stiffing of limbs for seconds. She also got infantile spasms similar to the first girl. Attacks were reduced about 50% after taking antiepileptic drugs and corticosteroid. Both patients had severe development delay, few hand function and poor eye contacts. Microcephaly and hypotonia were both found in two patients. Both structural brain defects and inherited metabolic disorders were excluded. DNA sequence screening show single base mutation of CDKL5 in both patients, one with a missense mutation of c.532C>T(p.R178W) and the other the nonsense mutation of c.163G>T (p.E55X). Our results support the importance of genetic testing of the CDKL5 gene in patients with early-onset epileptic encephalopathy especially with Rett-like features. Further study is needed with more cases of CDKL5 encephalopathy.