[Lennox syndrome associated with severe cerebellar dysfunction and peripheral neuropathy]

We reported a 33-year-old man with Lennox syndrome of 26 years' duration associated with unusual symptom complexes such as severe cerebellar ataxia and dysarthria, and peripheral neuropathy. His convulsive disorder was very intractable despite multiple anticonvulsants including phenytoin (PHT), phenobarbital (PB), primidone (PRM), valproate and so on. At the age of 25 he was no longer able to walk without help. PHT blood levels were kept almost within the therapeutic range, while PB blood levels tended to be greater than the therapeutic range. Needle EMG study revealed denervation pattern. Motor conduction velocity of the peroneal nerve was 25.2 m/s and sensory conduction velocity of the sural nerve could not be elicited. Brain CT and MRI showed the marked cerebellar atrophy predominant in the vermis. To our knowledge there were no previously reported cases of Lennox syndrome associated with such cerebellar dysfunctions and peripheral neuropathy. From the clinical course and laboratory findings, metabolic disorders and degenerative diseases were ruled out. We consider his cerebellar symptoms and peripheral neuropathy could be attributable to the long-term use of multiple anticonvulsants, i.e. PHT in combination with PB and PRM. These symptoms seem to be irreversible, because our patient's condition did not change after PHT and PB dose reduction, and discontinuation of PRM.