ICD-10 Code B96.4 – Proteus (mirabilis) (morganii) as the cause of diseases classified elsewhere (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B96.4 – Proteus (mirabilis) (morganii) as the cause of diseases classified elsewhere
What it is
B96.4 identifies Proteus species, specifically P. mirabilis or P. morganii, when they are documented as the cause of another disease. It is an additional code, not the primary diagnosis.
Clinical signs
Clinical features vary; refer to documentation. The record should link Proteus to a specific infectious condition, such as a urinary, wound, or other site-specific infection.
When to use this code
Use B96.4 when the provider states that Proteus mirabilis or Proteus morganii is the causative organism for an infection or other disease classified elsewhere. Pair it with the code for the underlying condition and any site or complication codes. If the organism is only suspected or not clearly documented as causal, check documentation.
Do not use for
Do not use this code for an unspecified bacterial infection or when another organism is identified as the cause. It is not used alone for the disease being treated.
Coding tip
Confirm the organism and the linked condition in the note before assigning B96.4.