GALACTOSIALIDOSIS -- EARLY and LATE INFANTILE TYPES

Protective Protein/Cathepsin A Deficiency ; PPCA deficiency; Cathepsin A Deficiency of GSL; Deficiency of Cathepsin A; Lysosomal Protein Deficiency; Neuraminidase with Beta galactosidase deficiency; Goldberg Syndrome

Galactosialidosis is a rare inherited disorder caused by a mutation of the CTSA gene. There are three types of galactosialidosis: early infantile, late infantile and juvenile/adult form.

The most severe form of galactosialidosis, the early infantile type, results in early onset of edema (may be prenatal); ascites, enlarged internal organs in the abdominal cavity (visceromegaly), and skeletal dysplasia (disproportionately short stature).

The late infantile type starts in the first year of life and shares many of the clinical features of early infantile type, but symptoms and neurological deterioration does not progress as rapidly. Intellectual disability is common.

Diagnostic testing: A direct assay system for protective protein/cathepsin A is available for prenatal diagnosis of galactosialidosis. After birth, the diagnosis is confirmed by reduced or absent beta-galactosidase enzymatic activity in white blood cells or in cultured skin fibroblasts. Urine tests may show excessive amounts of bound sialic acid and oligosaccharides (partially broken down sugars).

Physical findings: Physical findings for this conditions include:

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  Distinctive facial features (short nose, flat face, large head, bulging forehead);

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  Edema;

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  Ascites;

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  Umbilical or inguinal hernia;

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  Retinal cherry red spot;

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  Dysostosis multiplex;

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  Vertebral deformities;

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  Telangiectasias;

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  Enlarged liver and spleen (hepatosplenomegaly);

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  Enlarged heart (cardiomegaly);

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  Seizures;

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  Action myoclonus (abrupt spasms);

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  Ataxia;

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  Poor growth/short stature; and

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  Developmental delays or intellectual disability.

ICD-9: 271.8

Currently there is no cure for this disorder. Treatment is supportive and symptomatic.

SUGGESTED PROGRAMMATIC ASSESSMENT*

Suggested MER for Evaluation:

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

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  Laboratory studies with documentation of reduced or absent beta-galactosidase enzymatic activity in white blood cells or in cultured skin fibroblasts; and

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  Urine tests with evidence of elevated amounts of oligosaccharides.

Suggested Listings for Evaluation:

REMARKS

Evaluate juvenile/adult onset galactosialidosis by the body systems involved on a case-by-case basis.