ICD-10-CM A53.9 is the diagnosis code for Syphilis, unspecified. This code falls under the section "Infections with a predominantly sexual mode of transmission" within Chapter 1 — Certain infectious and parasitic diseases (A00-B99). It is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes. Medical coders and healthcare providers use this code to document and classify diagnoses in electronic health records, insurance claims, and clinical databases.
The following conditions should never be coded at the same time as A53.9. They are mutually exclusive:
Understanding where A53.9 sits in the ICD-10-CM classification helps ensure proper coding:
Yes, A53.9 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
A53.9 is the ICD-10-CM diagnosis code for "Syphilis, unspecified". It is used by healthcare providers to classify and document this condition in medical records and insurance claims.
The parent code of A53.9 is A53 ("Other and unspecified syphilis"). A53.9 provides a more specific classification within this category.
A53.9 is located in Section A50-A64 — "Infections with a predominantly sexual mode of transmission" within Chapter 1 of the ICD-10-CM Tabular List.
Use A53.9 when the patients documented diagnosis matches "Syphilis, unspecified" and the clinical documentation supports this level of specificity. Always verify with the latest ICD-10-CM guidelines and payer requirements.
The ICD-10-CM code for Syphilis, unspecified is A53.9.
Yes, A53.9 can be used as a primary diagnosis code since it is billable and specific.
A53.9 is in Chapter 1 of the ICD-10-CM Tabular List.
Type 1 Excludes for A53.9 include: syphilis NOS under two years of age (A50.2).
Yes, A53.9 is a valid ICD-10-CM code for the 2026 fiscal year, subject to official CMS updates.