A50.42 Late congenital syphilitic encephalitis

✓ Billable ICD-10-CM 2026
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The ICD-10-CM code for Late congenital syphilitic encephalitis is A50.42 (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 A50.42:

  • Encephalitis (chronic) (hemorrhagic) (idiopathic) (nonepidemic) (spurious) (subacute) › in (due to) › syphilis › congenital

Official Coding Guidelines

HIV Infections (TOC entry)

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

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.1.a
Infectious agents causing diseases in other chapters (TOC)

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

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.1.b

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

References

Cite This Page

Reference A50.42 with the canonical source and edition:

A50.42 — Late congenital syphilitic encephalitis. ICD-10 Coding Pro (ICD-10-CM FY2026). https://icd10codingpro.com/codes/A50.42

Canonical URL: https://icd10codingpro.com/codes/A50.42

Related Codes

Parent Code

A50 Congenital syphilis

Related Codes in A50

A50 Congenital syphilis A50.0 Early congenital syphilis, symptomatic A50.01 Early congenital syphilitic oculopathy A50.02 Early congenital syphilitic osteochondropathy A50.03 Early congenital syphilitic pharyngitis A50.04 Early congenital syphilitic pneumonia A50.05 Early congenital syphilitic rhinitis A50.06 Early cutaneous congenital syphilis A50.07 Early mucocutaneous congenital syphilis A50.08 Early visceral congenital syphilis A50.09 Other early congenital syphilis, symptomatic A50.1 Early congenital syphilis, latent A50.2 Early congenital syphilis, unspecified A50.3 Late congenital syphilitic oculopathy A50.30 Late congenital syphilitic oculopathy, unspecified A50.31 Late congenital syphilitic interstitial keratitis A50.32 Late congenital syphilitic chorioretinitis A50.39 Other late congenital syphilitic oculopathy A50.4 Late congenital neurosyphilis [juvenile neurosyphilis] A50.40 Late congenital neurosyphilis, unspecified
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Reviewed by Prajwal Shrestha, CPC, CRC
Certified Professional Coder (CPC) and Certified Risk Adjustment Coder (CRC) · AAPC Member ID 01997614 · About · Editorial policy · Content last reviewed: 2025-10-01

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