E75.09
BillableOther GM2 gangliosidosis
HCC Category Mapping
RxHCCHCC 41 — Lysosomal Storage Disorders
0.000What This Code Means
A rare inherited metabolic disorder where harmful fatty substances (GM2 gangliosides) accumulate in nerve and brain cells, causing progressive neurological damage, with a variant type not otherwise specified.
Coding Tips
- •Confirm the specific GM2 gangliosidosis variant (Tay-Sachs, Sandhoff, etc.) is documented; if specified, use the appropriate code instead
- •Ensure genetic testing results are referenced in the medical record to support diagnosis
Clinical Significance
Other GM2 gangliosidosis captures rare variants of GM2 ganglioside accumulation disorders not classified as Tay-Sachs or Sandhoff, primarily the GM2 activator protein deficiency (AB variant). This ultra-rare condition produces a clinical picture identical to Tay-Sachs but with normal hexosaminidase enzyme levels, making diagnosis challenging. The distinction requires specialized biochemical or genetic testing.
Documentation Requirements
- ✓Documented diagnosis of GM2 gangliosidosis specifying a variant other than Tay-Sachs or Sandhoff
- ✓Specialized testing: GM2 activator protein assay or GM2A gene mutation analysis
- ✓Normal hexosaminidase A and B levels with GM2 ganglioside accumulation on tissue analysis
- ✓Neurological assessment and disease progression documentation
- ✓Genetic counseling and family screening status
Commonly Confused Codes
E75.02 — Tay-Sachs disease: clinically identical but has hexosaminidase A deficiencyE75.01 — Sandhoff disease: different enzyme profile (hex A and B deficient)E75.00 — GM2 gangliosidosis, unspecified: use only when specific variant cannot be determinedE75.19 — Other gangliosidosis: for non-GM2 gangliosidosesE75.10 — Unspecified gangliosidosis: too non-specific