ICD-10 Code A52.03 – Syphilitic endocarditis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A52.03 – Syphilitic endocarditis
What it is
A52.03 identifies endocarditis caused by syphilis, an infection that affects the heart’s inner lining or valves. Use it when the provider documents syphilitic involvement of the endocardium.
Clinical signs
Clinical features vary; refer to documentation. Findings may include signs of infective endocarditis such as a new or changing murmur, embolic phenomena, or other cardiac involvement linked to syphilis.
When to use this code
Use this code when the record specifically states syphilitic endocarditis, endocarditis due to syphilis, or similar wording. It may appear with other manifestations of syphilis if the provider links them to the same infection.
Code only when the diagnosis is documented, not when syphilis is merely suspected. If the chart says endocarditis but does not identify syphilis as the cause, check documentation.
Do not use for
Do not use A52.03 for endocarditis from other infections or for nonspecific cardiac murmurs. Do not assume syphilitic cause without provider documentation.
Coding tip
Look for a clear causal link in the assessment or discharge diagnosis before assigning A52.03.