ICD-10 Code E79.2 – Myoadenylate deaminase deficiency (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code E79.2 – Myoadenylate deaminase deficiency
What it is
E79.2 identifies myoadenylate deaminase deficiency, a rare metabolic muscle disorder involving reduced activity of an enzyme needed for normal energy use during exertion. It is usually documented when the condition is confirmed or strongly suspected.
Clinical signs
Clinical features may include exercise-related muscle pain, early fatigue, cramps, or weakness. Findings are often nonspecific; refer to documentation and any confirmatory testing noted in the record.
When to use this code
Use E79.2 when the clinician documents myoadenylate deaminase deficiency as the diagnosis, including inherited or acquired forms if specified that way in the chart. It may also apply when the record links persistent exertional muscle symptoms to this enzyme deficiency. If the diagnosis is not clearly stated, check documentation before assigning the code.
Do not use for
Do not use this code for general muscle pain, fatigue, or cramps without documentation of the deficiency. It is also not for other metabolic myopathies or unspecified enzyme disorders.
Coding tip
Code only when the provider documents the deficiency; otherwise, query for clarification.