TN 69 (12-23)

DI 23022.890 Schindler Disease -- Type I

COMPASSIONATE ALLOWANCES INFORMATION

SCHINDLER DISEASE -- TYPE I

ALTERNATE NAMES

Neuroaxonal Dystrophy Schindler type; Alpha-N-Acetylgalactosaminidase Deficiency Type 1; NAGA Deficiency Type 1; Alpha NAGA Deficiency Schindler Type; Schindler Disease Type 1 Infantile Onset; Schindler Disease Infantile Type; Schindler Disease Classic Form

DESCRIPTION

Schindler Disease -- Type I is a rare inherited neurodegenerative disorder that is caused by mutations in the NAGA gene. The abnormal activity of the NAGA gene causes intracellular accumulations of glycoproteins and glycolipids and eventual cell death. The most affected organ is the central nervous system. Schindler Disease -- Type 1 is the most severe type of this disorder and has an infantile onset.

DIAGNOSTIC TESTING, PHYSICAL FINDINGS, AND ICD-9-CM/ICD-10-CM CODING

Diagnostic testing: Blood cells or skin biopsies document reduced or absent NAGA enzyme activity.

Physical findings:

  • Neurodevelopmental regression;

  • Profound intellectual disability;

  • Nystagmus (uncontrolled eye movements);

  • Visual impairment; and

  • Hypotonia (floppy muscle tone) that later evolves into muscle hypertonicity (too much muscle tone) and rigidity.

ICD-9: 271.8

ICD-10:E74.9

PROGRESSION

Infants with this disease have normal physical development during the first months of life after which they experience developmental regression beginning at 8 – 15 months. Worsening muscle tone and decreased movement, vision loss, and seizures may become evident as the disease progresses.

TREATMENT

There is no current cure for this disease. Treatment is supportive.

SUGGESTED PROGRAMMATIC ASSESSMENT*

Suggested MER for Evaluation:

  • Clinical history and examination that describes the diagnostic features of the impairment; and

  • Laboratory findings with decreased activity of alpha-NAGA

Suggested Listings for Evaluation:

DETERMINATION

LISTING

REMARKS

Meets

110.08 B

 

Equals

 

 

* Adjudicators may, at their discretion, use the Medical Evidence of Record or the listings suggested to evaluate the claim. However, the decision to allow or deny the claim rests with the adjudicator.


To Link to this section - Use this URL:
http://policy.ssa.gov/poms.nsf/lnx/0423022890
DI 23022.890 - Schindler Disease -- Type I - 12/27/2023
Batch run: 12/27/2023
Rev:12/27/2023