Infantile Refsum disease

Infantile Refsum disease is a degenerative disease belonging to the leukodystrophies from the group of peroxisomal diseases.

 

Description

It is a neurodegenerative disorder of fatty acids." >peroxisomes. It resembles the Zellweger syndrome but is very distinct from adult Refsum disease. It exhibits retinitis pigmentosa and peripheral neuropathy. Life expectancy may reach 20 years. This is an extremely rare disease affecting 1 in 20 million.

Clinical signs

The clinical signs appear at birth, frequently with retinitis pigmentosa often leading to blindness and serious hearing loss. Other symptoms such as cerebellar ataxia, nystagmus (involuntary shaky movements of the eyes), hypotonia, growth delay, mental retardation, minor facial dimorphism, osteoporosis, enlarged liver and hypocholesterolemia can occur . The abnormal formation of peroxisomes and their dysfunction lead to elevated plasma phytanic, pristanic, di-trihydroxycholestanoic and pipecolic acids, as well as very long chain fatty acids (VLCFA).

 

Genetics

The genes responsible for infantile Refsum disease are genes belonging to the PEX gene family: PEX1PEX26 or PEX2 that contribute to the formation and maintenance of peroxisomes.

Infantile Refsum disease is an autosomal recessive inherited disease. Thus, for a couple whose members are both carriers of the mutation, the risk of having an affected child (girl or boy) is 25% per pregnancy.

 

Diagnosis

 

It relies on the detremination of plasma VLFCA, phytanic and pipecolic acids.

 

Treatments

 

 

Diet

A diet with no phytanic acid, i.e. with no dairy products, beef, lamb or fat fisht, reduces the levels of phytanic acid. A supplementary diet with polyunsaturated fatty acids, oleic and erucic acids could be beneficial.

Plasmapheresis
Plasmapheresis (filtration and plasma exchange to remove toxic substances from the plasma) can sometimes be indicated.

 

Treatment of symptoms

 

Une prise en charge multidisciplinaire permettra d’améliorer la qualité de vie des enfants : lutte contre la douleur et la raideur.
A multidisciplinary care will improve the children quality of life: reduction of pain and stiffness.

 

Psychological care

 

This care should include not only the patient but also brothers and sisters of affected boys, parents, spouse and often several members of the same family.