Lennox-Gastaut syndrome (LGS) is one of the most severe types of childhood epilepsy.
It is usually resistant to treatment and associated with mental retardation. To delineate
the risk factors associated with the outcome of LGS, we evaluated, in a retrospective
and multicentre study, the course of the disease, EEG tracings, and intellectual function
in 101 patients. Inclusion criteria were the presence of tonic seizures as well as
slow spike and wave complexes in the EEG. The average documented observation period
was 16 years (range 4 - 31 years). Overall, the intellectual and neurological outcome
was poor. At the last follow-up, 38 % of the patients could not speak, 21 % were unable
to walk and only 4 % were free of seizures. Four independent risk factors for severe
mental retardation were identified by multivariate analysis. These were in a decreasing
order of importance: nonconvulsive status epilepticus (NCSE), odds ratio (OR) 25.2,
a previous diagnosis of West syndrome (OR 11.6), a symptomatic etiology of epilepsy
(OR 9.5), and an early age at onset of epilepsy (OR 4.7). The results highlight the
association between NCSE and the severity of mental retardation in patients with LGS;
this association appears to be independent of symptomatic etiology. Our data provide
an indirect evidence that, at least in some of the patients, NCSE is not only a concomitant
feature, but also a cause of severe mental retardation.
Key words
Lennox-Gastaut syndrome - Nonconvulsive status epilepticus - Mental retardation -
Prognostic factors
References
- 1 Aicardi J, Gomes A L.
The Lennox-Gastaut syndrome: clinical and electroencephalo-graphic features. Niedermeyer E, Degen R The Lennox-Gastaut Syndrome. New York; Alan R Liss 1988: 25-46
- 2 Aicardi J.
Lennox-Gastaut syndrome. Aicardi J. Epilepsy in Children. 2nd ed. International Review of Child Neurology
Series. New York; Raven Press 1994: 44-66
- 3 Baier H, Specht U.
Zur Prognose des Lennox-Gastaut Syndroms. Stefan H, Canger R, Spiel G Epilepsie 93. Reinbek; Eichhorn-Presse 1994: 362-369
- 4 Beaumanoir A, Foletti G, Magistris M, Volanschi D.
Status epilepticus in the Lennox-Gastaut Syndrome. Niedermeyer E, Degen R The Lennox-Gastaut Syndrome. New York; Alan R Liss 1988: 283-300
- 5 Beaumanoir A, Dravet C.
The Lennox-Gastaut syndrome. Roger J, Bureau M, Dravet C, Dreifuss FE, Perret A, Wolf P Epileptic Syndromes in
Infancy, Childhood and Adolescence. 2nd ed. London; John Libbey 1992: 115-132
- 6
Commission on Classification and Terminology of the International League Against Epilepsy
.
Proposal for revised clinical and electroencephalographic classification of epileptic
seizures.
Epilepsia.
1981;
22
489-501
- 7
Doose H, Völzke E.
Petit mal status in early childhood and dementia.
Neuropädiatrie.
1979;
10
10-14
- 8 Doose H.
Nonconvulsive status epilepticus in childhood: clinical aspects and classification. Delguado-Escueta AV, Wasterlain DM, Treiman DM, Porter RJ Advances in Neurology,
Vol. 34. Status Epilepticus. New York; Raven Press 1983: 83-92
- 9 Erba G, Browne T R.
Atypical absence, myoclonic, atonic, and tonic seizures and the “Lennox-Gastaut syndrome”. Browne TR, Feldman RG Epilepsy, Diagnosis and Management. Boston; Little Brown 1983:
75-94
- 10 Giovanardi Rossi P, Gobbi G, Melideo G, Parmeggiani A, Tullini A, Santucci M.
Myoclonic manifestations in the Lennox-Gastaut syndrome and other childhood epilepsies. Niedermeyer E, Degen R The Lennox-Gastaut Syndrome. New York; Alan R Liss 1988: 137-158
- 11
Heiskala H.
Community-based study of Lennox-Gastaut syndrome.
Epilepsia.
1997;
38
526-531
- 12
Hirt H R.
Zur Nosologie des Lennox-Gastaut Syndroms.
Nervenarzt.
1996;
67
109-122
- 13
Kruse R.
Absenzen-Status.
Acta Neurol Scand.
1976;
3
155-170
- 14
Lipton S A, Rosenberg P A.
Excitatory amino acids as a final common pathway for neurologic disorders.
N Engl J Med.
1994;
330
613-622
- 15
Oguni H, Hayashi K, Osawa M.
Long-term prognosis of Lennox-Gastaut syndrome.
Epilepsia.
1996;
37 (Suppl 3)
44-47
- 16
Ohtahara S, Ohtsuka Y, Kobayashi K.
Lennox-Gastaut syndrome: A new vista.
Psychiatr Clin Neurosci.
1995;
49
179-183
- 17
O'Regan M E, Brown J K.
Serum neuron specific enolase: a marker for neuronal dysfunction in children with
continuous EEG epileptiform activity.
Europ J Paediatr Neurol.
1998;
2
193-197
- 18
Rabinowicz A L, Correale J D, Bracht K A, Smith T D, DeGiorgio C M.
Neuron-specific enolase is increased after nonconvulsive status epilepticus.
Epilepsia.
1995;
36
475-479
- 19
Stores G, Zaiwalla Z, Styles E, Hoshika A.
Non-convulsive status epilepticus.
Arch Dis Child.
1995;
73
106-111
- 20
Theodore W H, Rose D, Patronas N. et al .
Cerebral glucose metabolism in the Lennox-Gastaut syndrome.
Ann Neurol.
1987;
21
14-21
- 21
Wasterlain C G, Shirasake Y.
Seizures, brain damage and brain development.
Brain Dev.
1994;
16
279-295
Prof. Dr. med. Rudolf Korinthenberg
Department of Neuropaediatrics and Muscular Disorders Paediatric University Hospital
Mathildenstr. 1
79106 Freiburg
Germany
Email: E-mail: rudokori@kkl200.ukl.uni-freiburg.de