2026 ICD-10-CM Diagnosis Code A50.41Late congenital syphilitic meningitis

ICD-10-CM Codes›A00–B99›A50-A64›A50

ICD-10-CM A50.41
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

A50.41 is a billable ICD-10-CM diagnosis code for late congenital syphilitic meningitis. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). Coders also document this condition as congenital syphilitic meningitis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Meningitis, Perinatal infections, and Sexually transmitted infections (excluding HIV and hepatitis).

Code Identity

ICD-10-CM Code
A50.41
Billable Status
Yes — Valid for Submission
Code Describes
Late congenital syphilitic meningitis
Short Description
Late congenital syphilitic meningitis
Same as the full description in the CMS dataset.
Parent Code
A50.4
Late congenital neurosyphilis [juvenile neurosyphilis]

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA50-A64Infections with a predominantly sexual mode of transmission
CategoryA50Congenital syphilis
This CodeA50.41Late congenital syphilitic meningitis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Congenital syphilitic meningitis
  • Late congenital neurosyphilis
  • Late congenital syphilis
  • Late congenital syphilitic meningitis
  • Meningitis caused by Spirochaetes
  • Syphilitic meningitis

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Meningitis(basal) (basic) (brain) (cerebral) (cervical) (congestive) (diffuse) (hemorrhagic) (infantile) (membranous) (metastatic) (nonspecific) (pontine) (progressive) (simple) (spinal) (subacute) (sympathetic) (toxic)
      • syphilitic (late) (tertiary)
        • congenital
    • Syphilis, syphilitic(acquired)
      • meningitis
        • congenital
    • Syphilis, syphilitic(acquired)
      • meningovascular
        • congenital

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR NVS001
Meningitis
Default principal diagnosis: inpatient No · outpatient No
CCSR PNL009
Perinatal infections
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR INF010
Sexually transmitted infections (excluding HIV and hepatitis)
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

Meningitis

Meningitis is inflammation of the thin tissue that surrounds the brain and spinal cord, called the meninges. There are several types of meningitis. The most common is viral meningitis. You get it when a virus enters the body through the nose or mouth and travels to the brain. Bacterial meningitis is rare but can be deadly.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert A50.41 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
090.42 Congen syph meningitis
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About A50.41Overview

Is A50.41 (Late congenital neurosyphilis [juvenile neurosyphilis]) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report late congenital syphilitic meningitis on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What is the ICD-9 equivalent of A50.41?

Under the General Equivalence Mappings, late congenital syphilitic meningitis converts to ICD-9-CM 090.42 (congen syph meningitis). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.