Heredopathia atactica polyneuritiformis (Refsum's Disease): a second trial of dietary therapy in two patients.

Two sibs with heredopathia atactica polyneuritiformis (Refsum's Disease) each had a relapse after ceasing to follow a special diet. On being placed on a very restricted low phytol, low phytanic acid diet both had marked subjective improvement, and marked objective improvement both in physical findings and in quantitative tests of strength, dexterity, and motor nerve conduction velocities, concomitant with a fall in serum phytanic acid levels. No relapse occurred in 22 months on this diet.