What is Farber Disease
Acid ceramidase deficiency manifesting as Farber disease is a very rare lysosomal storage disorder caused by mutations in the ASAH1 gene. When there’s a problem with this gene, the body does not produce enough of an enzyme called acid ceramidase. Without this enzyme, a lipid (a type of cholesterol-like substance important to the normal function of cells) called ceramide builds up to harmful amounts within cells all over the body.
Farber disease can be difficult to diagnose because of the wide range and severity of symptoms. Patients may be even be misdiagnosed or undiagnosed because their disease may look like something else. For example, some patients have been misdiagnosed with juvenile idiopathic arthritis (JIA). However, an enzyme activity test or a genetic test can help diagnose the disease.
Acid ceramidase deficiency can also present as spinal muscular atrophy with progressive myoclonic epilepsy (SMA-PME), a neurologic form of the disease. SMA-PME can also be diagnosed with the help of the same enzyme activity test or genetic test as Farber disease.
Symptoms
Acid ceramidase deficiency manifesting as Farber disease is characterized by symptoms that include most often:
- subcutaneous nodules (or bumps under the skin)
- joint pain, swelling, and stiffness/arthritis
- hoarse or weak voice
Additional symptoms may also include:
- impaired cognitive development (missing or losing developmental milestones)
- lung disease
- enlarged liver and/or spleen
- failure to thrive (low weight for age)
- central nervous system disease (like seizures or muscle weakness)
- shrinking bones in the fingers or toes
Those people affected with Farber disease will usually start showing symptoms in early childhood, but some may not experience certain symptoms until they are teenagers or adults. In its most rapidly progressive form, many patients with Farber disease do not live beyond the age of two years. More slowly progressive forms of Farber disease may be misdiagnosed because symptoms overlap with other diseases and are likely under-represented in medical literature.
Treatments
There are currently no treatments available which are specific to Farber disease. Some of the symptoms may be temporarily improved or stabilized by therapies such as anti-inflammatory medications, pain relievers or physical therapy. Doctors may also recommend stem cell transplant.
Support Links
- Courageous Parents Network: Support organization for families with seriously ill children. CourageousParentsNetwork.org
- Facebook Group for Farber Disease Families: A Facebook group dedicated to families living with Farber disease. facebook.com/groups/398392497575741/
- National Tay-Sachs and Allied Diseases Network: Services and support for families affected by Tay-Sachs and related genetic diseases like Farber disease. https://ntsad.org/index.php/farber
National Organization for Rare Disorders: Patient advocacy organization dedicated to individuals with rare diseases and the organization that serve them. https://rarediseases.org/rare-diseases/farbers-disease/
