Refsum diseases are rare genetic disorders that lead to issues with breaking down fat. Infantile Refsum is more severe and usually affects lifespan. People with adult Refsum can usually manage their symptoms by limiting their intake of certain foods.
Refsum disease is actually two distinct genetic disorders: infantile Refsum disease and adult Refsum disease. They’re both part of a group of diseases known as peroxisomal disorders, in which genetic changes (mutations) lead to problems breaking down certain types of fat. If you have this condition, you don’t have enzymes that help break down a type of fat called phytanic acid. As a result, phytanic acid builds up in your body.
Both adult and infantile Refsum disease can cause vision loss and phytanic acid buildup. But these two conditions result from two different gene changes (mutations) that develop before you’re born:
Refsum disease is extremely rare. Infantile Refusm happens in about 1 in 100,000 people, while adult Refsum happens in about 1 in 1 million people.
The symptoms of Refsum disease vary depending on how old you are when you start having symptoms.
If your child has infantile Refsum disease, they may be born very floppy and feed poorly. Their symptoms will depend on how severe their disease is. They may have seizures or abnormalities of their:
Infants with severe disease often die within the first year of life.
Older children can have:
The first symptom of adult Refsum disease is almost always a loss of night vision caused by retinitis pigmentosa. Your child may notice night blindness during their adolescence or teenage years. Or they may not develop symptoms until they’re adults. As they get older, retinitis pigmentosa may progress to loss of peripheral vision or blindness.
Other Refsum disease symptoms include:
Infantile Refsum is severe and disabling. Children have problems with feeding, seizures, vision and hearing. They have shortened lifespans from respiratory complications.
In adult Refsum, your vision will get worse over time. Weakness, sensory deficits and balance issues also gradually worsen over time. Physical stressors — like severe illness or surgery — can cause extremely high phytanic acid levels, leading to an irregular heartbeat or extreme weakness. Without treatment, arrhythmias can be life-threatening.
Refsum disease occurs because of a gene mutation (change) that you’re born with. You inherit these gene mutations from one or both of your biological parents.
There are over a dozen genes that can cause infantile Refsum. The most common are PEX1 (60%), PEX6 (15%), PEX12 (7.6%) and PEX26 (4.2%).
Adult Refsum also occurs because of an inherited gene mutation that’s present at birth. About 9 in 10 people with adult Refsum disease have a mutation in the PHYH gene. Most others with the condition have a PEX7 gene mutation.
Healthcare providers use different tests to arrive at a diagnosis for Refsum disease depending on your age. Then, they might order genetic tests to look for the gene mutations that cause Refsum disease.
For infantile Refsum, the most common diagnostic tests are very long-chain fatty acids, phytanic acid and pristanic acid. For adult Refsum, your healthcare provider may initially use a blood test to check your phytanic acid levels.
For infantile Refsum disease, your child’s healthcare provider will base their treatment on their symptoms. Interventions may include tube feeding, cataract removal, glasses, hearing aids, vitamins, anti-seizure medications and therapies/early intervention services for developmental delays.
For adult Refsum disease, treatment includes limiting your intake of foods that increase your phytanic acid levels, including:
Some people may also need a treatment called plasmapheresis to control phytanic acid buildup. In plasmapheresis, a healthcare provider draws your blood, filters extra phytanic acid out, then reinfuses it back into your body.
In the rare case that you develop an irregular heartbeat in adult Refsum disease, you may need treatment to control your heart rhythm, including:
Refsum disease is a genetic disorder, so there’s no way to prevent it.
If you have Refsum disease or think you could be a carrier, you may consider genetic testing. Genetic testing identifies the gene mutation that causes Refsum disease. A genetic counselor can help you understand test results, including your chances of passing any genetic conditions to your children.
Children with infantile Refsum generally have severe developmental disabilities and require many medical interventions. Unfortunately, despite vigilant care, people with the condition have shortened lifespans due to the severity and nature of this disorder.
In adult Refsum, most people successfully manage their symptoms by limiting their intake of foods that are high in phytanic acid. With treatment, symptoms like dry skin, numbness or tingling often disappear. You may deal with vision or hearing loss long term. In some people, a lost sense of smell never returns.
If you have Refsum disease or think you could, you may want to ask your healthcare provider:
A note from Cleveland Clinic
It can be scary to hear that you or your child have a rare genetic disorder. But getting a diagnosis is the first step to understanding what’s going on. Your healthcare providers will work together to develop a treatment plan that’s tailored to your symptoms and outlook (or those of your child.) Especially if you have a child with Refsum disease, it might help to connect with a support group. Although everyone is different, it may help to talk about your experience with other parents and caregivers.
Last reviewed by a Cleveland Clinic medical professional on 07/24/2023.
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