refsum disease

REFUSUMS DISEASE

By ROBIN MATHEW

Outline• Definition• Genetic makeup• Clinical components• Cause of disorder• Symptoms• Treatment• Prognosis

REFSUMS DISEASE• Disorder associated with impaired oxidation of

phytanic acid and elevated phytanic levels in CNS• Norwegian neurologist Sigvald Bernhard Refsum (1907–1991)

• 1945• Level of phytanic acid in blood – Normal - ≤ 0.2mg/dl– Refsum disease - 10-50mg/dl

GENETIC makeup• Autosomal recessive• Refsum disease 1 -Phytanoyl-CoA hydroxylase• Refsum disease 2• Peroxin 7• Europeans• Gene:-PHYH

Clinical components• Pertinent physical findings include cardiac, and skin

defects.• Neurologic/ophthalmologic signs are as follows:– Nystagmus– Retinitis Pigmentosa– Anosmia– Sensorineural deafness

Phytanoyl-CoA hydroxylase Gene

• Locus: 10p13

Causes of disorder• Abnormal buildup of fatty acid called a

phytanic acid

• Normally broken down by Peroxisomes

Symptoms• Night blindness• Retinitis Pigmentosa• Deafness• Dry, scaly skin • Shortened fingers or toes

DIAGNOSIS• Chronic and intermittent polyneuritis• Relapsing infectious polyneuritis • mitochondrial myopathies• Acute intermittent porphyria• Recurrent exposure to toxins• Various hereditary motor neuropathies

TREATMENTDIET• Less amount of phytanic acid in diet• Slow progression of eye/hearing changes

Plasmapheresis:-plasma exchange

Prognosis

Refsum disease is treatable although incurable

Even if improved by diet, although changes in vision, hearing, and sense of smell may be irreversible

Phytanic acid is found in foods like dairy products and beef