ICD-10 Code B58.81 – Toxoplasma myocarditis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B58.81 – Toxoplasma myocarditis
What it is
B58.81 identifies myocarditis caused by Toxoplasma infection. Use it when documentation states the heart muscle is inflamed due to toxoplasmosis.
Clinical signs
Clinical features vary; refer to documentation. Reported findings may include chest pain, arrhythmia, heart failure symptoms, or evidence of myocardial inflammation with toxoplasma infection.
When to use this code
Use B58.81 when the provider documents toxoplasma myocarditis, toxoplasmic cardiac involvement, or myocarditis attributed to Toxoplasma gondii. It applies when the heart diagnosis is clearly linked to the infection. If the record only notes toxoplasmosis without cardiac involvement, do not assign this code.
Do not use for
Do not use this code for myocarditis from another cause, such as viral or autoimmune disease. Check documentation if the chart does not clearly connect the myocarditis to toxoplasmosis.
Coding tip
Confirm both the myocarditis and the toxoplasma etiology are documented before assigning B58.81.