ICD-10 Code A77.49 – Other ehrlichiosis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A77.49 – Other ehrlichiosis
What it is
A77.49 identifies ehrlichiosis caused by Ehrlichia species that is not further specified elsewhere. Use it for documented ehrlichial infection when the record does not support a more specific code.
Clinical signs
Clinical features vary; refer to documentation. Commonly reported findings include fever, headache, malaise, myalgia, and sometimes rash or laboratory evidence of acute tick-borne infection.
When to use this code
Use this code when the provider documents ehrlichiosis without naming a more specific Ehrlichia type. It also fits cases described as other or unspecified ehrlichiosis after clinical evaluation.
Assign it only when the chart supports an ehrlichial infection, not merely tick exposure or a nonspecific febrile illness. Check documentation if the organism, site, or disease form is unclear.
Do not use for
Do not use A77.49 for Lyme disease, anaplasmosis, or other tick-borne infections with separate codes. Do not use it when ehrlichiosis is not documented or remains only suspected.
Coding tip
Code from the provider’s final diagnosis wording and confirm whether a more specific ehrlichiosis code applies before defaulting to A77.49.