INFANTILE NEURONAL CEROID LIPOFUSCINOSES

ALTERNATE NAMES

Haltia-Santavuori disease; CNL1; INCL; NCL; Finnish form of NCL; Santavuori-Haltia disease

DESCRIPTION

Infantile Neuronal Ceroid Lipofuscinoses (INCL) is one form of a family of at least eight genetically separate neurodegenerative disorders that result from excessive accumulation of lipopigments (lipofuscin) in the body’s tissues. These lipopigments are made up of fats and proteins. The lipofuscin materials build up in nerve cells and many other organs, including the liver, spleen, myocardium and kidneys. The Infantile type of NCL (INCL) is caused by the mutation of the CLN1 gene. The mutation typically results in a deficient form of a lysomal enzyme called palmitoyl protein thioesterase 1 (PPT1). In INCL, infants appear normal at birth but at 6 months visual loss appears and leads to complete retinal blindness by age 2. By 3 years of age a vegetative state is reached and by 4 brain death occurs. Affected children fail to thrive and have abnormally small heads (microcephaly), short, sharp muscle contractions called myoclonic jerks. Initial signs of this disorder include delayed psychomotor development with progressive deterioration, other motor disorders or seizures.

DIAGNOSTIC

TESTING, PHYSICAL FINDINGS, AND ICD-9-CM CODING

Definitive diagnostic lab testing: Testing for diagnosis of INCL includes eye exam to detect a loss of vision, neurological exam, EEG to record the electrical activity in the brain for seizures, CT scan to detect any decaying brain areas or MRI to create a picture of the brain, electrical studies of the eyes (VER and ERG) to detect eye problems, skin or tissue sampling to spot INCL deposits and enzyme assay that looks for specific missing lysosomal enzymes.

ICD-9: 330.1 Cerebral lipidoses

ONSET AND PROGRESSION

INCL has the most rapid progression of all the NCL types. The maximum age before death is 10 – 12 years of age.

TREATMENT

There are no current treatments for this condition. However, seizures may be controlled or reduced with the use of anti-epileptic drugs. Additionally, physical, speech and occupational therapies may help affected individuals retain functioning for as long as possible.

SUGGESTED PROGRAMMATIC ASSESSMENT*

Suggested MER for Evaluation: Laboratory reports showing enzyme activity of the PPT1 enzyme; complete neurological, ophthalmological, and mental examinations (including intellectual and psychological functioning) may be needed if one of these examinations alone is insufficient to meet a listing.

Suggested Listings for Evaluation:

DETERMINATION

LISTING

Meets Listing

110.08

111.02

111.17

Medical Equals