Epilepsy and Other Clinical Features in a Child with Partial Deletion of Chromosome 15 Q

A 2-year-old child was delivered at term after twin pregnancy by ICSI with intrauterine growth retardation. Birth weight was 1710 g., length 43 cm, and head circumference 31.5. APGAR score was 6I, 8V, 9X. No family history of malformations, epilepsy, or intellectual disability was reported. The twin is healthy. Neonatal brain ultrasound was normal.

Psychomotor delay was reported: he could sit unsupported at around 12 months of age and at 24 months he is unable to walk alone. First phonemes appeared at 24 months. The neurological examination showed severe generalized hypotonia with joint hyperlaxity, brisk symmetrical reflexes, and severe psychomotor delay. Severe dorsolumbar scoliosis was evident. Dysmorphological evaluation revealed a triangular face, low-set ears, microcephalia, and micrognathia. A craniospinal MRI performed at 2 years of age showed hypoplasia of the adenohypophysis associated with a minor dysmorphism of the brainstem characterized by a shorter midbrain, thinning of the periventricular white matter with enlargement of the lateral ventricles and frontal subarachnoid spaces. Molecular karyotyping (array-CGH) was performed showing partial deletion of 15 q 25.3 q 26.1 that includes 10 genes OMIN. The most important are CHD2, ACAN, and PLIN1. At the age of 18 months, he presented monthly tonic–clonic generalized seizures and daily absences. An electroencephalogram showed high amplitude centrotemporal spikes or sharp-and-slow wave complexes bilaterally with severe increase during the sleep. He was started on valproic acid and then topiramate with partial seizures control.