Type 1 diabetes mellitus, presymptomatic, Stage 1

This code signifies the earliest stage of type 1 diabetes mellitus, characterized by the presence of two or more diabetes-related autoantibodies without any symptoms or abnormal glucose levels. It represents an autoimmune process targeting pancreatic beta cells that has begun but has not yet manifested as dysglycemia.

Apply this code when a patient has been identified through screening to have multiple positive islet autoantibodies (e.g., GAD65, ICA, IA-2A, ZnT8A) but maintains normal glucose tolerance and is asymptomatic. Documentation must clearly state the presence of autoantibodies and the absence of hyperglycemia or clinical symptoms of diabetes.

• Do not use this code if the patient exhibits any signs of glucose dysregulation (e.g., impaired glucose tolerance, elevated A1c, or symptomatic hyperglycemia).
• This code is distinct from "prediabetes" (R73.03), which indicates impaired glucose metabolism without autoantibody confirmation of an autoimmune process.
• Ensure physician documentation explicitly states "presymptomatic, Stage 1" or provides sufficient detail to support this specific stage of type 1 diabetes.