A 38-year-old Pakistani patient presented with a 3-year history of facial grimacing, dysphagia, dysarthria, and stutter. More recently she had developed mild chorea. On examination, she had facial tics, eye twitching, excessive blinking, tongue protrusions, dystonic opening of the mouth and choreiform movement of the limbs, particularly on the right side . There was no family history of neurological disease but her parents were first cousins. Her full blood count was normal but a blood film showed acanthocytosis (image). A diagnosis of choreo-acanthocytosis was confirmed by demonstration of reduced chorein expression in red cell membranes.
Choreo-acanthocytosis is one of four rare neurological syndromes with movement disorders linked to atrophy of the basal ganglia, acanthocytosis and normal beta lipoproteins, designated collectively neuroacanthocytosis (Table 1).
|Syndrome||Mutated gene and inheritance||Clinicopathological features|
|Choreo-acanthocytosis||VPS13A, autosomal recessive||Adult onset progressive neurodegeneration, myopathy, often epilepsy|
|McLeod phenotype||KX, X-linked recessive||Adult onset progressive neurodegeneration, myopathy, cardiomyopathy, weak or absent expression of Kell antigens|
|Huntingdon-like disease 2a||JPH3, autosomal dominant||Adult onset progressive neurodegeneration|
|Pantothenate-kinase associated neurodegenerationa||PANK2, autosomal recessive||Childhood onset progressive neurodegeneration, pallidal degeneration, sometimes retinitis pigmentosa|
The common link between the neurological and erythroid abnormality is an abnormality of cell membranes. Detection of acanthocytes in a blood film is diagnostically useful.