2027 ICD-10-CM Diagnosis Code A50.49Other late congenital neurosyphilis

ICD-10-CM Codes›A00–B99›A50-A64›A50

ICD-10-CM A50.49
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

A50.49 is a billable ICD-10-CM diagnosis code for other late congenital neurosyphilis. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 97 through 99. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 96 closely related codes. Coders also document this condition as acquired syphilis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Perinatal infections and Sexually transmitted infections (excluding HIV and hepatitis).

Code Identity

ICD-10-CM Code
A50.49
Billable Status
Yes — Valid for Submission
Code Describes
Other late congenital neurosyphilis
Short Description
Other late congenital neurosyphilis
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 CodeA50.49Other late congenital neurosyphilis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acquired syphilis
  • Juvenile tabes dorsalis
  • Late quaternary neurosyphilis
  • Sensorineural deafness due to late congenital syphilis
  • Spastic spinal syphilitic paralysis

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to A50.49: its own notes plus those printed at A50.4, block A50-A64, and Chapter 1. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • diseases generally recognized as communicable or transmissible

Applicable To

Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.

  • Juvenile tabes dorsalis

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From A50.4 Late congenital neurosyphilis [juvenile neurosyphilis] applies to 7 codes
From Block A50-A64 Infections with a predominantly sexual mode of transmission applies to 142 codes
  • nonspecific and nongonococcal urethritis (N34.1)
  • Reiter's disease (M02.3-)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Block A50-A64 Infections with a predominantly sexual mode of transmission applies to 142 codes
  • human immunodeficiency virus [HIV] disease (B20)
From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • carrier or suspected carrier of infectious disease (Z22.-)
  • certain localized infections - see body system-related chapters
  • infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
  • infectious and parasitic diseases specific to the perinatal period (P35-P39)
  • influenza and other acute respiratory infections (J00-J22)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From A50.4 Late congenital neurosyphilis [juvenile neurosyphilis] applies to 7 codes
  • code to identify any associated mental disorder
From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • code to identify resistance to antimicrobial drugs (Z16.-)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name A50.49, its category, or a range that includes it.

Applicable To 1

These notes mention A50.49.

  • O98.1 Syphilis complicating pregnancy, childbirth and the puerperium
    Conditions in A50-A53 names A50-A53, which includes this code

Excludes1 1

These codes carry an Excludes1 note naming A50.49: they are not reported together with it, unless the two conditions are unrelated.

  • G94 Other disorders of brain in diseases classified elsewhere
    encephalopathy in congenital syphilis (A50.49)

Excludes2 3

These codes carry an Excludes2 note naming A50.49: its condition is not part of those codes, and both may be reported when the patient has both.

  • Block P35-P39 Infections specific to the perinatal period
    congenital syphilis (A50.-) names A50.-, which includes this code
  • P37 Other congenital infectious and parasitic diseases
    congenital syphilis (A50.-) names A50.-, which includes this code
  • Block A65-A69 Other spirochetal diseases
    syphilis (A50-A53) names A50-A53, which includes this code

Code First 2

These codes say to code first a condition named in the note, and A50.49 is one of the conditions named.

  • G91.4 Hydrocephalus in diseases classified elsewhere
    congenital syphilis (A50.4-) names A50.4-, which includes this code
  • J99 Respiratory disorders in diseases classified elsewhere
    congenital syphilis (A50.-) names A50.-, which includes this code

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

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

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

Clinical InformationClinical

  • Syphilis, Congenital

    syphilis acquired in utero and manifested by any of several characteristic tooth (hutchinson's teeth) or bone malformations and by active mucocutaneous syphilis at birth or shortly thereafter. ocular and neurologic changes may also occur.

Patient EducationClinical

Syphilis

Syphilis is a sexually transmitted infection (STI) caused by bacteria. It infects the genital area, lips, mouth, or anus of both men and women. You usually get syphilis from sexual contact with someone who has it. It can also pass from mother to baby during pregnancy.

Read the full article at MedlinePlus

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

Convert A50.49 to ICD-9-CMHistory

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

ICD-9-CM
090.49 Juvenile neurosyph NEC
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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About A50.49Overview

What is the ICD-10 code for other late congenital neurosyphilis?

The ICD-10-CM code for other late congenital neurosyphilis is A50.49 (sometimes written as A5049). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is A50.49 (Late congenital neurosyphilis [juvenile neurosyphilis]) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other late congenital neurosyphilis on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does A50.49 group to?

When other late congenital neurosyphilis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 98, 99, 97, with relative weights from 1.5249 to 3.8208 depending on complications. Higher weights mean higher Medicare reimbursement.

Is A50.49 a CC or MCC?

CMS lists A50.49 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 96 closely related codes in its exclusion list.

Can A50.49 be reported with A50.53?

Not as a rule. The Excludes1 note at A50.4, which applies to A50.49, lists "Hutchinson's triad (A50.53)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).