ICD-10 Code B26.83 – Mumps nephritis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B26.83 – Mumps nephritis
What it is
B26.83 identifies kidney inflammation caused by mumps infection. Use it when documentation links nephritis directly to mumps, not to another renal condition.
Clinical signs
Clinical features vary; refer to documentation. Typical records may note mumps with renal involvement, such as urinary abnormalities or signs of nephritis, when the provider documents the association.
When to use this code
Use B26.83 when the provider diagnoses mumps nephritis or clearly states that nephritis is due to mumps. Apply it for confirmed post-infectious renal involvement in the setting of mumps. If the chart only says mumps without kidney involvement, do not assign this code.
Do not use for
Do not use this code for uncomplicated mumps, unspecified nephritis, or kidney disease from another cause. Check documentation if the renal finding is not explicitly linked to mumps.
Coding tip
Always verify the causal link in the note; B26.83 requires documented mumps-related nephritis.