A genetic disorder that occurs quite rarely and causes problems with breaking down fat is called Refsum disease. When this condition occurs in children, it is more severe and often affects their life expectancy. In most cases, the symptoms of people with Refsum disease are managed with some dietary changes.
Generally, this condition is divided into two types, including infantile Refsum disease and adult Refsum disease. Moreover, both conditions are a part of a group of disorders called peroxisomal disorders. These conditions are caused by genetic mutations (changes) that cause problems with breaking down some types of fat. Those who suffer from Refsum disease do not have the enzymes that are required to break down a type of fat known as phytanic acid. Hence, this type of fat begins to build up in the body.
What is The Difference Between Adult and Infantile Refsum disease?
While both disorders cause vision loss and phytanic acid buildup, they are caused by different gene mutations. These gene changes often develop during pregnancy.
- Infantile Refsum disease – This type is a part of a group of diseases known as Zellweger spectrum disorders. It negatively affects babies and young children and often causes the following symptoms. Examples include developmental delays, liver disease, seizures, poor feeding, and weak muscle tone. Usually, infantile Refsum disease is more severe in children compared to adult Refsum disease because it impacts their life expectancy.
- Adult Refsum disease – In such cases, the condition occurs in late childhood or later. The most common symptoms include weakness, numbness of the hands and feet, hearing impairment, and loss of smell or vision. While adult Refsum disease does not cause developmental delays and seizures, it often causes severe heart problems later in life.
This condition occurs very rarely, and infantile Refsum disease affects about 1 in 100,000 children, and adult Refsum disease affects about 1 in 1 million adults.
Symptoms
The symptoms often appear differently among people who develop Refsum disease. It depends on the type and severity of the condition, existing health problems, age, and preferences. Check below some examples:
Infantile Refsum Disease
These include:
- Abnormalities of the kidneys, liver, or bones
- Seizures
- Poor growth
- Delayed development
- Hearing and visual problems
Generally, infants with severe Refsum disease often die within the first 12 months of age.
Adult Refsum Disease
While the primary symptom of this disorder in adults is loss of night vision caused by retinitis pigmentosa, they may also experience other symptoms. For example:
- Anosmia (loss of smell)
- Tingling and numbness in the hands and feet
- Balance problems
- Hearing loss (deafness)
- Ichthyosis (rough and scaly skin patches)
- Cataracts (cloudy vision)
- Arrhythmia (irregular heart rhythm)
- Heart failure
If you or your child experiences any of the previous symptoms, immediately seek medical care.
Causes
This condition appears due to a gene mutation (change) that a person gets during pregnancy from their biological parents. In most cases, this condition is present at birth (congenital). In general, there are multiple genes that may cause infantile Refsum disease. For example, PEX1 (60%), PEX6 (15%), PEX12 (7.6%), PEX26 (4.2%), and others.
Moreover, about 90% of people with adult Refsum disease have a mutation in the PHYH gene. It is also inherited from the biological parents during pregnancy.
What Are The Possible Complications of Refsum Disease?
The following complications often occur due to the buildup of phytanic acid in the body. While infantile Refsum disease is more severe, adults may also have complications. Check below some examples:
- Respiratory problems
- Sensory deficits
- Irregular heartbeats
- Extreme weakness
- Cerebral ataxia
- Retinitis pigmentosa
- Cataracts
- Cardiomyopathy
- Death
This article does not contain all possible complications of Refsum disease. In any case, you can consult with your doctor about ways to reduce the risk or prevent previous complications.
How to Prevent Refsum Disease?
Unfortunately, this condition is a genetic disorder and it cannot be prevented. However, you can perform genetic tests before pregnancy to check for the abnormal gene that causes Refsum disease. It is important to understand the risks of having children with this disorder.
Diagnosis
Usually, doctors use different tests to diagnose this genetic condition. However, to confirm it, your doctor will take a sample of blood to perform a genetic test. It helps identify the abnormal gene that causes the disease and makes the best treatment plan for you. If your doctor suspects your child may have infantile Refsum disease, they will perform some tests to check the levels of long-chain fatty acids, phytanic acid, and prostanic acid. If test results show high levels of these acids, it may indicate Refsum disease.
Treatment
The treatment for infantile Refsum disease is often based on the symptoms. Usually, doctors recommend a feeding tube, cataract removal, eyeglasses, hearing aids, vitamins, anti-seizure medications, and therapies for developmental delays. Healthcare professionals may also recommend dietary changes for people with adult Refsum disease. You should avoid the following foods because they significantly increase the phytanic acid levels. These include:
- Beef and lamb
- Dairy products
- Fatty fish (including tuna, cod, or haddock)
In some cases, doctors may recommend a treatment called plasmapheresis. It helps control phytanic acid buildup.
In rare cases, people may develop heart problems (such as arrhythmia) and may need additional treatment. Check below some options that doctors often prescribe for people with adult Refsum disease with heart complications:
- Medicines – For example, beta-blockers, calcium channel blockers, or anticoagulants (also known as blood-thinners). These medicines are used to control the heart rhythm and reduce the risk of developing stroke.
- Cardioversion – This is a controlled electric shock that helps restore normal heart rhythm.
- Implantable cardioverter defibrillator – This treatment involves a specific device that is placed under the skin that monitors and regulates the heartbeats.
- Catheter ablation – Commonly, doctors prescribe this treatment to treat arrhythmia. It is a minimally invasive procedure that intentionally damages diseased heart tissue.
Frequently Asked Questions
What are the symptoms of Refsum disease?
These include:
- Vision problems (such as retinitis pigmentosa)
- Hearing loss
- Muscle weakness
- Numbness and tingling in the hands or feet
In some cases, it is difficult to diagnose Refsum disease because its symptoms are very similar to other health conditions. If any of the previous symptoms occur, immediately see a doctor for diagnosis and treatment.
What foods should you avoid with Refsum disease?
These include:
- Red meat and dairy (including beef and lamb)
- Fatty fish
- Animal fats (including beef suet, ghee, and some animal-fat-containing margarines)
- Ready-made sauces
- Some vegetables (such as red and yellow bell peppers, rocket salad, and others)
- Algae and flaxseed oils
For more details, discuss it with your doctor.
What is the prognosis for Refsum disease?
While the life expectancy of babies fluctuates, in general, the condition is fatal. In adults, the condition is not fatal, but it can cause serious health problems. These include loss of smell, vision disorders, numbness and weakness of the feet and hands, hearing impairment, and others. Ask your healthcare provider if you have additional questions.
