Abstract
Transient hemiparesis has long been recognized as an aura or accompaniment of migaine headaches and the genetic basis for familial hemiplegic migraine (FHM) is in the process of resolution.
An association of FHM and progressive cerebellar ataxia, not remarkable in view of the localization of both disorders to chromosome 19, has been repoted (1, 2). Migraine headaches may also be a symptom of cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASIL), another occupant of chromosome 19, although in this case headache is overshadowed by recurrent strokes, pseudobulbar palsy and progressive dementia. Mitochondrial encephalomyelopathy, lactic acidosis and stroke-like episodes (MELAS) syndrome may also present with migraine-like headaches. It is clear that such headaches may be symptomatic of some underlying progressive neurological disorders by interacting with the central pathways responsible for the pathogenesis of migraine.
How does AHC fit in with this group? The admirable genetic study reported in this issue effectively blackballs AHC from the exclusive chromosome 19 club. Are there any clinical grounds to include it in the wider classification of migraine? AHC usually starts in infancy and is characterized by repeated attacks of episodic hemiplegia, dystonia and autonomic disturbance, terminating in progressive mental and physical deterioration. The least constant feature is headache which is occasionally reported at the onset of AHC paroxysms. In none of the four patients described in this issue by Haan et al. was headache mentioned as part of the attack.
It is an appropriate time to reassess the place of AHC when revising the 1988 International Headache Society (IHS) criteria for the diagnosis of migraine and related disorders. It would appear logical to have AHC grouped with CADASIL and MELAS under the heading of ‘migraine-like headaches associated with progressive neurological disorders’.