Case report Nocturnal frontal lobe epilepsy in mucopolysaccharidosis Paolo Bonanni a,⇑ , Anna Volzone a , Giovanna Randazzo a , Lisa Antoniazzi a , Angelica Rampazzo b , Maurizio Scarpa b , Lino Nobili c a Epilepsy and Clinical Neurophysiology Unit, IRCCS “E. Medea”, Conegliano, TV, Italy b Department of Paediatrics, University of Padova, Italy c “Claudio Munari” Epilepsy Surgery Centre, Niguarda Ca’Granda Hospital, Milan, Italy Received 25 July 2013; received in revised form 5 December 2013; accepted 11 December 2013 Abstract Nocturnal frontal lobe epilepsy (NFLE) is an epileptic syndrome that is primarily characterized by seizures with motor signs occurring almost exclusively during sleep. We describe 2 children with mucopolysaccharidosis (MPS) who were referred for signif- icant sleep disturbance. Long term video-EEG monitoring (LT-VEEGM) demonstrated sleep-related hypermotor seizures consis- tent with NFLE. No case of sleep-related hypermotor seizures has ever been reported to date in MPS. However, differential diagnosis with para- somnias has been previously discussed. The high frequency of frontal lobe seizures causes sleep fragmentation, which may result in sleep disturbances observed in at least a small percentage of MPS patients. We suggest monitoring individuals with MPS using periodic LT-VEEGM, particularly when sleep disorder is present. Moreover, our cases confirm that NFLE in lysosomal storage diseases may occur, and this finding extends the etiologic spectrum of NFLE. Ó 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved. Keywords: Sleep disturbances; Epilepsy; Mucopolysaccharidosis 1. Introduction Nocturnal frontal lobe epilepsy (NFLE) is an epilep- tic syndrome primarily characterized by seizures that occur almost exclusively during sleep. Seizures are char- acterized by autonomic activation and bizarre motor behaviour of increasing complexity and duration; they range from simple and brief stereotyped motor events to paroxysmal arousals and major attacks [1,2]. The ictal signs associated with these seizures suggest that frontal lobes may be involved. NFLE is a heterogeneous disorder with onset during infancy or childhood [3]; it may present in sporadic and familial forms, induce various seizure types, and be drug resistant in approximately 30% of patients. Symptom- atic aetiology is present only in 13% of NFLE patients and most NFLE cases remain cryptogenic [1]. The majority of symptomatic patients experience symptoms due to focal cortical dysplasia [2]. Only 1 case with aspartylglucosaminuria and NFLE has been reported to date [4]. We describe 2 patients with mucopolysaccharidosis (MPS) who were referred for significant sleep distur- bance. Long term video-EEG monitoring (LT-VEEGM) of these patients demonstrated sleep- related hypermotor seizures consistent with NFLE. 0387-7604/$ - see front matter Ó 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.braindev.2013.12.002 ⇑ Corresponding author. Address: Epilepsy and Clinical Neurophys- iology Unit, IRCCS E. Medea, Via Costa Alta 37, Conegliano 31015, TV, Italy. Tel.: +39 0438 414347; fax: +39 0438 410101. E-mail address: paolo.bonanni@cn.lnf.it (P. Bonanni). www.elsevier.com/locate/braindev Brain & Development xxx (2014) xxx–xxx Please cite this article in press as: Bonanni P et al. Nocturnal frontal lobe epilepsy in mucopolysaccharidosis. Brain Dev (2014), http:// dx.doi.org/10.1016/j.braindev.2013.12.002