2026 ICD-10-CM Diagnosis Code A52.78Syphilis of other musculoskeletal tissue

ICD-10-CM Codes›A00–B99›A50-A64›A52

ICD-10-CM A52.78
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

A52.78 is a billable ICD-10-CM diagnosis code for syphilis of other musculoskeletal tissue. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 557 through 558. Coders also document this condition as bursitis caused by bacterial infection. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Sexually transmitted infections (excluding HIV and hepatitis).

Code Identity

ICD-10-CM Code
A52.78
Billable Status
Yes — Valid for Submission
Code Describes
Syphilis of other musculoskeletal tissue
Short Description
Syphilis of other musculoskeletal tissue
Same as the full description in the CMS dataset.
Parent Code
A52.7
Other symptomatic late syphilis

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA50-A64Infections with a predominantly sexual mode of transmission
CategoryA52Late syphilis
This CodeA52.78Syphilis of other musculoskeletal tissue

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Bursitis caused by bacterial infection
  • Bursitis due to late syphilis
  • Infectious disorder of tendon
  • Syphilis of muscle
  • Syphilis of synovium
  • Syphilis of tendon
  • Syphilitic bursitis

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Late syphilitic bursitis
  • Syphilis stage unspecified of bursa
  • Syphilis stage unspecified of muscle
  • Syphilis stage unspecified of synovium
  • Syphilis stage unspecified of tendon

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.

    • Atrophy, atrophic(of)
      • muscle, muscular (diffuse) (general) (idiopathic) (primary)
        • syphilitic
    • Bursitis
      • syphilitic
    • Leontiasis
      • syphilitic (late)
    • Myositis
      • in (due to)
        • syphilis
          • late
    • Synovitis
      • in (due to)
        • syphilis (late)
    • Synovitis
      • syphilitic
    • Syphilis, syphilitic(acquired)
      • bursa (late)
    • Syphilis, syphilitic(acquired)
      • muscle
    • Syphilis, syphilitic(acquired)
      • synovium
    • Syphilis, syphilitic(acquired)
      • tendon (late)
    • Tenosynovitis
      • in (due to)
        • syphilis (late)
    • Verneuil's disease(syphilitic bursitis)

Clinical ClassificationClinical

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

CCSR INF010
Sexually transmitted infections (excluding HIV and hepatitis)
Default principal diagnosis: inpatient Yes · outpatient Yes

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 A52.78 to ICD-9-CMHistory

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

ICD-9-CM
095.6 Syphilis of muscle
Approximate The match is approximate rather than exact.
ICD-9-CM
095.7 Syphilis of tendon/bursa
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 A52.78Overview

Is A52.78 (Other symptomatic late syphilis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report syphilis of other musculoskeletal tissue on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does A52.78 group to?

When syphilis of other musculoskeletal tissue is the principal diagnosis on an inpatient stay, it groups to MS-DRG 557, 558, with relative weights from 0.8932 to 1.4869 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of A52.78?

Under the General Equivalence Mappings, syphilis of other musculoskeletal tissue converts to ICD-9-CM 095.6 (syphilis of muscle) and 095.7 (syphilis of tendon/bursa). 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.