Farber Disease is a rare lysosomal storage disorder caused by a deficiency of the enzyme acid ceramidase. This enzyme is produced based on instructions from the ASAH1 gene and is responsible for breaking down a fatty substance called ceramide. Ceramide plays a role in cell membranes and signaling, but when it is not properly broken down, it accumulates within lysosomes. This accumulation leads to inflammation, tissue damage, and the formation of lipid-filled granulomas throughout the body. The disorder primarily affects the joints, skin, respiratory system, and nervous system, resulting in progressive disability. Farber disease varies widely in severity, ranging from severe infantile forms to milder later-onset forms.

Symptoms usually appear in infancy or early childhood and worsen over time. Children commonly develop: • Painful, swollen joints • Progressive joint stiffness and contractures • Subcutaneous nodules near joints and pressure points • Hoarse or weak voice due to laryngeal involvement Other features include: • Failure to thrive and poor growth • Developmental delay • Enlarged liver and spleen (hepatosplenomegaly) • Respiratory difficulties and recurrent infections • Vision and hearing problems • Neurological involvement in severe forms, including seizures and cognitive decline The disease course varies. Severe infantile forms often lead to death in early childhood, while milder forms may allow survival into adolescence or adulthood with significant disability.

Farber Disease is caused by mutations in the ASAH1 gene.

Diagnosis is based on: • Clinical evaluation of characteristic symptoms • Enzyme assays demonstrating reduced acid ceramidase activity • Genetic testing confirming ASAH1 mutations • Tissue biopsy in some cases showing lipid-laden cells Early diagnosis is important for management and family counseling.

There is no definitive cure for Farber Disease. Treatment focuses on symptom management and supportive care, including: • Pain control and anti-inflammatory medications • Physiotherapy to maintain joint mobility • Respiratory support • Surgical intervention for severe contractures Hematopoietic stem cell transplantation has been attempted in selected cases without severe neurological involvement, with variable results. Research into enzyme replacement and gene therapy is ongoing.