A50.31 Late congenital syphilitic interstitial keratitis
The ICD-10-CM code for Late congenital syphilitic interstitial keratitis is A50.31 (FY2026). It is a billable, claim-ready diagnosis code.
Classification
- Section
- A50-A64: Infections with a predominantly sexual mode of transmission (A50-A64)
- Category A50
- 38 codes (33 billable)
- FY2026 Status
- Stable since FY2024
Also Known As
ICD-10-CM Alphabetic Index entries that lead to A50.31:
- Keratitis (nodular) (nonulcerative) (simple) (zonular) › syphilitic (congenital) (prenatal)
- Syphilis, syphilitic (acquired) › keratitis (congenital) (interstitial) (late)
- Keratitis (nodular) (nonulcerative) (simple) (zonular) › punctata › syphilitic (profunda)
- Keratitis (nodular) (nonulcerative) (simple) (zonular) › interstitial (nonsyphilitic) › syphilitic (congenital) (late)
- Syphilis, syphilitic (acquired) › congenital › interstitial keratitis
- Keratitis (nodular) (nonulcerative) (simple) (zonular) › in (due to) › syphilis
- Syphilis, syphilitic (acquired) › congenital › late, or 2 years or more after birth NEC › interstitial keratitis
U.S. Hospital Utilization
A50.31 appeared in too few sampled U.S. inpatient stays in 2023 to report a national estimate (AHRQ suppresses counts of 10 or fewer) — a rare inpatient 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