Abstracts

Rationale: Continuous spike and waves during sleep (CSWS) is an epileptic encephalopathy that presents with neurocognitive regression, seizures and an electroencephalogram pattern of electrical status epilepticus during sleep (ESES). CSWS is closely related to Landau-Kleffner syndrome (LKS), which also affects school-aged children, causing loss of previously acquired function and cognitive decline. We present a diagnostically challenging case of neuronal ceroid lipofuscinosis, initially diagnosed with CSWS with novel EEG finding of ESES. Methods: Chart review and literature review of PubMed using the search terms 'ceroid-lipofuscinosis 5' AND 'continuous spike wave of sleep' OR 'electrical status epilepticus of sleep' Results: A 7-year-old female presented with significant physical and cognitive decline, several clinical seizures types and EEG consistent with electrical status epilepticus of sleep. Patient was diagnosed with CSWS and started on steroids with improvement in symptoms initially. However, patient continued to deteriorate. Epilepsy gene panel revealed pathogenic mutation for NCL 5 (homozygous c.526dupA, exon 3). NCL has not been previously described in literature with ESES. The diagnosed guided appropriate management for the patient. Conclusions: Neuronal ceroid lipofuscinosis is a rare diagnosis and should be strongly considered for any child presenting with regression. Regression and ESES is highly suggestive of CSWS and LKS, therefore NCL is often not on the differential. Our patient's clinical course highlights the importance of recognizing the presentation of ESES in NCL. Early diagnosis allows for prompt appropriate management and counseling for patients and improvement in quality of life. Funding: No funding