ICD-10 Code G13.2 – Systemic atrophy primarily affecting the central nervous system in myxedema (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G13.2 – Systemic atrophy primarily affecting the central nervous system in myxedema
What it is
This code identifies a rare neurologic degenerative syndrome associated with myxedema, or severe hypothyroid-related tissue changes. Use it when documentation states systemic atrophy primarily affecting the central nervous system in myxedema.
Clinical signs
Clinical features vary; refer to documentation. Reported findings may include progressive neurologic decline, gait disturbance, cognitive changes, or other central nervous system signs linked to myxedema.
When to use this code
Use G13.2 when the provider clearly documents systemic atrophy primarily affecting the central nervous system in myxedema. It may be appropriate in endocrine or neurologic records where the condition is named as the diagnosis.
Do not infer this code from hypothyroidism alone. If the record only mentions myxedema, neurologic symptoms, or generalized atrophy without this specific diagnosis, check documentation before coding.
Do not use for
Do not use for uncomplicated hypothyroidism, nonspecific encephalopathy, or other neurodegenerative disorders. Check documentation if the chart does not explicitly connect the CNS atrophy to myxedema.
Coding tip
Code only when the provider links the neurologic atrophy to myxedema by name; otherwise, query for clarification.