Refsum's disease

Refsum's disease, also known as adult Refsum disease or phytanic acid storage disease, is a rare autosomal recessive peroxisomal disorder characterized by the accumulation of phytanic acid in tissues and plasma. This metabolic defect leads to a progressive neurological syndrome affecting vision, hearing, and motor function, often presenting with retinitis pigmentosa, peripheral neuropathy, ataxia, and anosmia.

Use this code for patients diagnosed with Refsum's disease based on clinical presentation and confirmed by biochemical testing showing elevated phytanic acid levels. Documentation should clearly indicate the diagnosis of Refsum's disease, often supported by genetic testing results or enzyme assays.

• Differentiate from infantile Refsum disease (IRD), which is a peroxisome biogenesis disorder (PBD) and has a different genetic basis and clinical course.
• Ensure documentation specifies "Refsum's disease" or "phytanic acid storage disease" to avoid confusion with other metabolic disorders.
• Consider co-occurring conditions such as retinitis pigmentosa or peripheral neuropathy, which may require additional coding.