ICD-10 Code B58 – Toxoplasmosis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B58 – Toxoplasmosis
What it is
B58 identifies toxoplasmosis, an infection caused by the parasite Toxoplasma gondii. It may be acquired after exposure to contaminated food, soil, or cat feces, or passed congenitally.
Clinical signs
Clinical features vary; refer to documentation. Common findings can include mild flu-like illness, lymph node enlargement, eye involvement, or neurologic disease in severe cases.
When to use this code
Use B58 when the record clearly documents toxoplasmosis as the confirmed diagnosis. It applies to symptomatic infection, ocular disease, or other organ involvement when the provider identifies toxoplasmosis. If the note only mentions exposure or screening, do not code B58.
Do not use for
Do not use this code for suspected toxoplasmosis without confirmation. Also avoid it when the chart documents only congenital exposure, carrier status, or another diagnosis explaining the findings.
Coding tip
Check the provider’s wording for confirmed toxoplasmosis and any documented site or complication before assigning B58.