ICD-10 Code E13.21 – Other specified diabetes mellitus with diabetic nephropathy (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code E13.21 – Other specified diabetes mellitus with diabetic nephropathy
What it is
This code identifies diabetes mellitus from another specified cause, with kidney involvement described as diabetic nephropathy. Use it when the record links the diabetes to nephropathy and the type is not classified elsewhere.
Clinical signs
Clinical features vary; refer to documentation. Common charted findings may include diabetic kidney disease, proteinuria, or chronic renal impairment attributed to diabetes, but the diagnosis must be documented by the provider.
When to use this code
Use E13.21 when the provider documents other specified diabetes mellitus and specifically states diabetic nephropathy. It is appropriate when the record ties the kidney disease to the diabetes and does not identify type 1, type 2, or gestational diabetes.
Apply it only when nephropathy is part of the documented diabetic complication. If the note says chronic kidney disease without a diabetic link, or the diabetes type is unclear, check documentation before coding.
Do not use for
Do not use this code for diabetes without kidney involvement, or for diabetic nephropathy linked to a different diabetes category. Do not assume the complication if the provider has not documented the relationship.
Coding tip
Confirm both the diabetes category and the stated kidney complication before assigning E13.21.