ICD-10 Code A79.89 – Other specified rickettsioses (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A79.89 – Other specified rickettsioses
What it is
A79.89 identifies a rickettsial infection that does not fit a more specific ICD-10 category. Use it when the record clearly documents another specified rickettsiosis, but not a named code elsewhere.
Clinical signs
Clinical features vary; refer to documentation. Rickettsioses commonly present with fever, headache, rash, and a history of tick or arthropod exposure, but the exact pattern depends on the organism.
When to use this code
Use this code when the provider documents a specified rickettsial illness and no more precise code is available. It may apply after diagnostic workup identifies a rickettsiosis, but the record does not name a specific type. Check documentation for the exact organism or syndrome before assigning A79.89.
Do not use for
Do not use this code for a more specific rickettsial diagnosis that has its own ICD-10 code. Avoid it when the chart only says “suspected” rickettsiosis or gives insufficient detail.
Coding tip
Confirm the provider’s final diagnosis and look for a more specific rickettsial code before defaulting to A79.89.