A53.0 Latent syphilis, unspecified as early or late

The ICD-10-CM code for Latent syphilis, unspecified as early or late is A53.0 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

1: Certain infectious and parasitic diseases (A00-B99)

Section

A50-A64: Infections with a predominantly sexual mode of transmission (A50-A64)

Category A53

3 codes (2 billable)

FY2026 Status

Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to A53.0:

• Serology for syphilis › reactivated
• Positive › Wassermann reaction
• Positive › serology for syphilis
• Syphilis, syphilitic (acquired) › latent
• Positive › VDRL
• Serology for syphilis › positive
• Syphilis, syphilitic (acquired) › latent › follow-up of latent syphilis
• Syphilis, syphilitic (acquired) › latent › date of infection unspecified

Inclusion Terms

• Latent syphilis NOS
• Positive serological reaction for syphilis

U.S. Hospital Utilization

• An estimated 7,290 U.S. inpatient stays in 2023 included A53.0 among the documented diagnoses.
• 180 stays listed it as the principal diagnosis.

Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.

Official Coding Guidelines

HIV Infections (TOC entry)

a. Human Immunodeficiency Virus (HIV) Infections .............................................................. 19

Infectious agents causing diseases in other chapters (TOC)

b. Infectious agents as the cause of diseases classified to other chapters ................................. 22

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool
• AHRQ — HCUP National Inpatient Sample, Frequencies by Diagnosis Code (2016–2023)