Definition:
Kufs/Adult-onset NCL/CLN4 Disorder is part of a group of progressive degenerative neurometabolic disorders known as neuronal ceroid lipofuscinoses (NCLs). NCLs are characterized by an abnormal accumulation of lipopigaments, which are substances combined from fats and proteins within the brain’s nerve cells, eyes, skin, muscle, and within other tissues throughout the body.

Skin biopsy shows characteristic inclusions in CLN4. This includes a variety of profiles that overlap other forms of neuronal ceroid lipofuscinoses.

Research has located a mutated gene responsible for Kufs/Adult-onset NCL/CLN4, although the protein that the gene codes has not been identified.

It is estimated that the NCLs affects two to four of every 100,000 live births in the United States.

Symptoms:
Symptoms of Kufs/Adult-onset NCL/CLN4 disorder begin before 40 years of age, when signs of dementia begin to appear. Motor skills decline and seizures are common. This disorder does not cause blindness as many other NCLs do.

Inheritance Pattern:
Both autosomal recessive and dominant inheritance patterns have been described in Kufs disease.

Life Expectancy:
Life expectancy is variably reduced in Kufs disease.

Diagnosis and Testing:
A urine test may be utilized to diagnose Kufs/Adult-onset NCL/CLN4. The test measures increased levels of a chemical called dolichol. A biopsy of a tissue or skin sample to look for cellular deposits unique to NCL disorders often will confirm a diagnosis. Diagnostic tests include electroencephalogram, or EEG, to locate seizure activity in the brain, eye exams to look for optical complications characteristic of NCL disorders, and brain scans to search for changes in the brain’s appearance.

Linkage has been described for NCL4, but the precise gene and mutation has not yet been identified.

Treatment:
There is no cure for Kufs/Adult-onset NCL/CLN4 disorder. Treatment is limited to reducing or controlling the symptoms of this disorder. Neurologists can assist in keeping seizures or nervous system complications under control. Physical and occupational therapists can help the affected individual maintain muscle movement and reduce muscle discomfort.