ICD-10-CM · General

M10.10

Gout caused by lead toxicity, assigned when the affected joint or anatomical site is not documented or cannot be specified.

Verified May 8, 2026 · 6 sources ↓

Status
Billable
Chapter
13
Related CPT
5
Region
General
Drawn from CDCICD10DataAAPCOutsourcestrategiesPrecisionhub

Documentation tips

What should appear in the chart to support M10.10.

Source · Editorial brief grounded in 6 cited references ↓

  • Record the confirmed or suspected lead exposure source (occupational, environmental, ingestion) and reference any blood lead level result to support the toxic etiology.
  • Identify the affected joint by name whenever possible — switching from M10.10 to a site-specific M10.1x code improves specificity and reduces audit risk.
  • Append T56.0- (toxic effects of lead and its compounds) as an additional code per ICD-10-CM tabular instruction for M10.1 codes.
  • Distinguish acute flare from chronic gouty arthropathy in the note; if chronic with or without tophi, the M1A.1- subcategory applies rather than M10.10.
  • Document serum uric acid levels, synovial fluid analysis results, and any imaging showing joint changes to substantiate the gout diagnosis.

Related CPT procedures

Procedure codes commonly billed with M10.10. Linking the right diagnosis to the right procedure is what establishes medical necessity.

Source · CMS LCDs · AAOS specialty guidance · claims-pattern analysis

Common coding pitfalls

The recurring mistakes coders make with M10.10 and adjacent codes.

Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓

  • Skipping the required companion code T56.0-: M10.10 requires a 'Use Additional' code for toxic effects of lead — omitting it is a known audit flag.
  • Using M10.10 when the joint is documented: if the provider names even one joint, a site-specific M10.11–M10.19 code is required and M10.10 becomes incorrect.
  • Confusing lead-induced gout with drug-induced gout (M10.2-) or renal impairment gout (M10.3-): the etiology must be explicitly attributed to lead in the documentation before assigning M10.10.
  • Defaulting to M10.9 (gout, unspecified) when the cause is documented as lead: M10.9 is appropriate only when etiology is unknown, not when lead exposure is identified.
  • Billing M10.1 (parent code) instead of M10.10: M10.1 is non-billable; M10.10 is the billable specificity level when site is unspecified.

Clinical context

Source · Editorial summary grounded in 6 cited references ↓

M10.10 is the fallback code within the M10.1 (lead-induced gout) subcategory when the provider has documented a causal link to lead exposure but has not identified a specific joint. Lead-induced gout arises from chronic lead toxicity impairing renal uric acid excretion, driving hyperuricemia and subsequent crystal deposition. Because the mechanism is toxic rather than idiopathic or drug-related, it requires a different parent code than M10.0 (idiopathic) or M10.2 (drug-induced).

When a specific joint is named in the note — shoulder, elbow, wrist, hand, hip, knee, ankle/foot, or vertebrae — move to the appropriate site-specific code under M10.1 (e.g., M10.161 for right knee, M10.162 for left knee). Reserve M10.10 only when the documentation genuinely lacks a joint location. Per ICD-10-CM Tabular List instruction, also code the toxic effect of lead using T56.0- to capture the underlying exposure.

This code sits in Chapter 13 (M00–M99, Diseases of the Musculoskeletal System and Connective Tissue) and is fully billable as of FY2026 (effective October 1, 2025). It covers acute gout attacks, gout flares, and podagra when the etiology is lead and the site is unspecified. If the condition has become chronic with or without tophi, consider the M1A.1- category instead.

Sibling codes

Other billable codes under M10.1 (laterality / anatomic variants).

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 6 cited references ↓

01When is M10.10 the correct code versus a site-specific M10.1x code?
Use M10.10 only when the provider has documented lead as the gout etiology but has not identified a specific joint. If any joint is named — knee, ankle, wrist, etc. — assign the corresponding site-specific code (e.g., M10.161 right knee, M10.172 left ankle and foot).
02Is a companion code required with M10.10?
Yes. The ICD-10-CM Tabular List instructs coders to also assign T56.0- (toxic effects of lead and its compounds) to identify the source of the lead toxicity. Submitting M10.10 without T56.0- is incomplete coding.
03How does M10.10 differ from M10.9 (gout, unspecified)?
M10.9 is used when the type and cause of gout are unknown. M10.10 is used when the cause is specifically documented as lead exposure but the affected site is unspecified. If lead etiology is in the chart, M10.10 is the correct choice over M10.9.
04Should chronic lead-induced gout still be coded M10.10?
No. Chronic gout belongs in the M1A category. Use M1A.10X0 (lead-induced chronic gout, unspecified site, without tophus) or M1A.10X1 (with tophus) depending on documentation of tophi.
05Can M10.10 be used for an acute gout flare in a patient with known prior lead exposure?
Yes, provided the provider attributes the current acute flare or attack to lead-induced hyperuricemia and no specific joint is documented. The M10 category covers acute gout, gout attacks, and gout flares per ICD-10-CM Tabular notation.
06What distinguishes lead-induced gout (M10.1-) from drug-induced gout (M10.2-)?
The etiology determines the subcategory. Lead-induced gout results from heavy metal toxicity impairing renal urate excretion; drug-induced gout is caused by medications (e.g., diuretics, cyclosporine). The provider's documented etiology drives this distinction — coders cannot infer it independently.
07Does M10.10 require laterality?
No. The unspecified-site designation in M10.10 inherently means no anatomical location — including laterality — has been specified. Laterality becomes relevant only once a specific joint is documented, at which point the appropriate six-character site-and-side code under M10.1 applies.

Mira AI Scribe

Mira AI Scribe captures lead exposure history (occupational, environmental, or ingestion source), blood lead level if ordered, the joint or body region involved in the current flare, serum uric acid value, and any prior gout episodes. That documentation drives selection between M10.10 (site unspecified) and the site-specific M10.1x codes, and supports the required companion T56.0- toxic-effect code — preventing a downcode to M10.9 or a claim rejection for missing etiology linkage.

See how Mira captures M10.10 documentation

Related ICD-10 codes

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