NeurometPlus

Incidence

Rare AR disease. Farber disease is rare. Only 78 cases have been reported. It is likely that the incidence is somewhat higher than would be suggested by this small number, as the diagnosis may not be suspected in atypical cases, and the diagnostic assays are performed in only a small number of specialized laboratories. Except for people of Jewish descent, all ethnic groups appear to be represented. Consanguinity was known to be present in 5 out of 35 families.

Clinical Characteristics

The disease start between birth and 4 months of age. Initiate with swelling, pain and sensitivity of joints of hands and feet. Hoarse cry. Then a progressive severe generalized arthropathy follows with ankylosis, with progressive dysphonia due to laryngeal nodules. There are characteristic subcutaneous nodules on dorsal surfaces of joints areas and spine.Severe dyspnea due to pulmonary infiltrates follows later. FTT due to severe malnutrition is seen. Febrile episodes are frequently seen. Moderate hepatomegaly. No splenomegaly. Destructive bone lesions are seen on X rays. Foamy histiocytes are found in bone marrow and fron subcutaneous nodules. There is severe muscle atrophy, absent DTRs (due to pain and ankylosis?). EMG show denervation. There is pyramidal signs. Blindness with macular changes is observed. Also corneal and lenticular opacities may occur. Seizures of variable type are occasionally seen. There is usual progressive dementia. CSF protein is usually very elevated. Death occur before age 2 yrs.

Precipitants

no

Provocation Tests

no

Diagnostic Procedures

EB-F, EB-W. The most definitive diagnostic test is the demonstration of deficient acid ceramidase activity in white blood cells, cultured skin fibroblasts, or cultured amniocytes. Foamy histiocytes are found in bone marrow and from subcutaneous nodules. Typical inclusions in EM. Evaluation of tissue material by GC/MS or thin-layer chromatography (TLC) show ceramide accumulation. CSF protein is usually very elevated.