Neuropediatrics 2002; 33(6): 314-319
DOI: 10.1055/s-2002-37087
Original Article

Georg Thieme Verlag Stuttgart · New York

Spinal Muscular Atrophy with Progressive Myoclonic Epilepsy: Report of New Cases and Review of the Literature

G. Haliloglu 1 , A. Chattopadhyay 2 , L. Skorodis 2 , A. Manzur 2 , E. Mercuri 2 , B. Talim 3 , Z. Akçören 3 , Y. Renda 1 , F. Muntoni 2 , H. Topaloğlu 1
  • 1Department of Child Neurology, Hacettepe Children's Hospital, Ankara, Turkey
  • 2Neuromuscular Unit, Department of Paediatrics, Imperial College School of Medicine, Hammersmith Hospital, Du Cane Road, London, UK
  • 3Department of Pathology, Hacettepe Children's Hospital, Ankara, Turkey
Further Information

Publication History

Received: 5 July 2002

Accepted after Revision: 9 November 2002

Publication Date:
06 February 2003 (online)

Abstract

Spinal muscular atrophy (SMA) is a clinically and genetically heterogeneous disease characterised by loss of motor function and muscle atrophy due to anterior horn cell degeneration. The most common variant is chromosome 5-linked proximal SMA, ranging in severity from congenital onset and infantile death to onset in adult life. Genetically separate variants with different distribution of weakness and/or additional features such as central nervous system involvement have been described. A rare variant with associated myoclonic epilepsy and lower motor neuron disease had been previously described in three families before the SMN gene, responsible for the common form of SMA, was isolated. We report four patients from two additional families affected by a syndrome characterised by severe and progressive myoclonic epilepsy and proximal weakness, tremor and lower motor neuron disease proven by electrophysiologic and muscle biopsy findings. Extensive metabolic investigations were normal and genetic analysis excluded the SMN gene. This study confirms that the association of myoclonic epilepsy and motor neuron disease represents a separate clinical and genetic entity from chromosome 5-linked SMA, the primary defect of which remains unknown.

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Prof. M. D. Haluk Topaloğlu

Department of Child Neurology · Hacettepe Children's Hospital

06100 Ankara

Turkey

Email: htopalog@hacettepe.edu.tr