2026 ICD-10-CM Diagnosis Code M1A.0520Idiopathic chronic gout, left hip, without tophus (tophi)

ICD-10-CM Codes›M00–M99›M05-M14›M1A

ICD-10-CM M1A.0520
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M1A.0520 is a billable ICD-10-CM diagnosis code for idiopathic chronic gout, left hip, without tophus (tophi). The 7th character 0 reports chronic gout without tophus formation. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 553 through 554. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Gout.

Code Identity

ICD-10-CM Code
M1A.0520
Billable Status
Yes — Valid for Submission
Code Describes
Idiopathic chronic gout, left hip, without tophus (tophi)
Short Description
Idiopathic chronic gout, left hip, without tophus (tophi)
Same as the full description in the CMS dataset.
Parent Code
M1A.052
Idiopathic chronic gout, left hip

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM05-M14Inflammatory polyarthropathies
CategoryM1AChronic gout
This CodeM1A.0520Idiopathic chronic gout, left hip, without tophus (tophi)

Clinical ClassificationClinical

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

CCSR MUS033
Gout
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Gout

Gout is a common type of inflammatory arthritis. It causes pain, swelling, and redness in one or more joints. It usually happens as a flare, which can last for a week or two and then gets better. The flares often begin in your big toe or a lower limb.

The full article covers:

  • What is gout?
  • What causes gout?
  • Who is more likely to develop gout?
  • What are the symptoms of gout?
  • How is gout diagnosed?
  • What are the treatments for gout?

Read the full article at MedlinePlus

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

Convert M1A.0520 to ICD-9-CMHistory

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

ICD-9-CM
274.02 Chr gouty atrph wo tophi
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 M1A.0520Overview

Is M1A.0520 (Idiopathic chronic gout, left hip) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report idiopathic chronic gout, left hip, without tophus (tophi) on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character 0 in M1A.0520 mean?

The final character 0 reports chronic gout without tophus formation, in this case involving the idiopathic chronic gout, left hip.

What MS-DRG does M1A.0520 group to?

When idiopathic chronic gout, left hip, without tophus (tophi) is the principal diagnosis on an inpatient stay, it groups to MS-DRG 553, 554, with relative weights from 0.8301 to 1.2963 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of M1A.0520?

Under the General Equivalence Mappings, idiopathic chronic gout, left hip, without tophus (tophi) converts to ICD-9-CM 274.02 (chr gouty atrph wo tophi). 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.