Harp syndrome, characterized by hypoprebetalipoproteinemia, acanthocytosis, retinitis pigmentosa, and pallidal degeneration, is described in three patients from the National Hospital, Queen Square, London, Newcastle General Hospital, and the Royal Free Hospital, London, UK. An 18-year-old woman presented with intellectual subnormality, night blindness, and dysarthria and dysphagia associated with orobucco-lingual dystonia. T2-weighted MRI showed the “eye-of-the-tiger” sign. This patient’s sister and mother had hypoprebetalipoproteinemia but no retinitis pigmentosa or pallidal degeneration. Two patients with a forme-fruste Harp syndrome had the clinical and radiologic features but no lipid abnormality. [1]
COMMENT. HARP syndrome is distinguished from Hallervorden-Spatz disease (HSD) by acanthocytosis and the abnormality of lipoprotein. The authors note that all cases of HARP syndrome have been sporadic and lack the autosomal recessive feature of HSD. For further reports of HARP syndrome, see Progress in Pediatric Neurology II, PNB Publ, 1994, p477.