ICD-10 Code E10.A2 – Type 1 diabetes mellitus, presymptomatic, Stage 2 (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code E10.A2 – Type 1 diabetes mellitus, presymptomatic, Stage 2
What it is
E10.A2 identifies presymptomatic stage 2 type 1 diabetes mellitus, when autoimmune disease is present and glucose abnormalities have begun, but overt clinical diabetes has not yet fully developed.
Clinical signs
Clinical features vary; refer to documentation. This stage is typically recognized by evidence of islet autoimmunity with early dysglycemia, even if classic symptoms of diabetes are not yet present.
When to use this code
Use this code when the record specifically documents presymptomatic stage 2 type 1 diabetes mellitus. It is appropriate for patients identified through screening or specialist evaluation before symptomatic diabetes is diagnosed. Check documentation if the stage is not clearly stated.
Do not use for
Do not use this code for established type 1 diabetes with symptoms, or for other diabetes types. If the record only says “at risk,” “prediabetes,” or autoimmune markers without stage 2 documentation, check documentation.
Coding tip
Code E10.A2 only when stage 2 is explicitly documented; do not infer it from antibody positivity alone.