Refsum Disease

Excerpt

What is now known as Refsum disease was initially described by Sigvald Refsum as heredoataxia hemeralopica polyneuritiformis in 1945, but its name was changed to heredopathia atactica polyneuritiformis the following year. Today, Refsum disease is synonymous with "adult Refsum disease" and "classic Refsum disease." The Online Catalog of Human Genes and Genetic Disorders (OMIM) records adult Refsum disease as phenotype MIM number #266500. The condition is rare, autosomal recessive, and classified as a disorder of peroxisomal function.

Peroxisomes are single membrane-bound intracellular organelles that generate peroxide for use in metabolic functions. Their functions are far-reaching and include a vast complement of lipid catabolism and biogenesis functions; the dysfunction in lipid catabolism is responsible for Refsum disease. The fundamental characteristic of disorders of peroxisome function is that they are due to a deficiency in the function of a single enzyme. This produces specific metabolic abnormalities.

Refsum disease is caused by a deficiency of the phytanoyl-CoA hydroxylase, which results in deficient catabolism of phytanic acid and an excess. The core of Refsum disease's clinical characteristics is due to the effects of phytanic acid buildup on the nervous system.

Since the terminology surrounding Refsum disease can be confusing, it is worth emphasizing that Refsum disease is distinct from infantile Refsum disease, which falls within the Zellweger spectrum disorders. These are classified as disorders of peroxisomal biogenesis and assembly. For more information on infantile Refsum disease, see StatPearls' companion topic, "Zellweger Spectrum Disorder."