Refsum's disease is a rare, autosomal recessive neurometabolic disease, characterised biochemically by accumulation of phytanic acid in blood and tissues.1 This is due to deficiency of the peroxisomal enzyme phytanoyl-CoA-hydroxylase (PAHX), caused by mutations of the PAHX gene on chromosome 10.2 As phytanic acid is exclusively of exogenous origin, patients with Refsum's disease are treatable by a diet low in phytanic acid and the phytanic acid precursor.3 A clinical tetrad of peripheral neuropathy, retinitis pigmentosa, cerebellar syndrome, and increased CSF protein concentration was reported in most patients with Refsum's disease.1 4

We present long term clinical and biochemical findings in an Arabian patient, finally diagnosed as having Refsum's disease. In 1991, this 34 year old man from Egypt presented with progressive gait disorder and visual field constriction. Born in Souhag, he descended from a consanguineous union. At 19 years of age, he sustained thyphoid fever; since then he had noted hyposmia. At 31 years of age, he emmigrated to Austria. Symptoms started insidiously 1 year later. Neurological examination showed bilateral sickle form restriction of temporal visual fields, wasting of leg muscles with foot drop, absence of tendon reflexes, and loss of proprioceptive sensation. Laboratory findings were normal, except for mild neutropenia (white cell count 3.2 g/l) and raised …