E88.4 vs G31.82
E88.4 (Mitochondrial metabolism disorders) compared with G31.82 (Leigh's disease), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.
Can these codes be reported together?
No — do not report together. E88.4 carries an Excludes1 note covering G31.82: “Leigh's encephalopathy (G31.82)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
Side by side
| E88.4Mitochondrial metabolism disorders | G31.82Leigh's disease | |
|---|---|---|
| Billing status | Non-billable header | Billable |
| Classification | E00-E89 — Endocrine, Nutritional and Metabolic Diseases (E00-E89) | G00-G99 — Diseases of the Nervous System (G00-G99) |
| Definition | Mitochondrial metabolism disorders is a non-billable ICD-10-CM category code (E88.4). | Leigh's disease is a billable ICD-10-CM diagnosis code (G31.82). |
| Includes | — | Subacute necrotizing encephalopathy |
| Use additional code | codes for associated conditions | code, if applicable, for codes G31.0-G31.83, G31.85-G31.9, to identify: dementia with anxiety (F02.84, F02.A4, F02.B4, F02.C4) dementia with behavioral disturbance (F02.81-, F02.A1-, F02.B1-, F02.C1-) |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources