What is ICD-10 code H49.813?

H49.813 is the ICD-10-CM diagnosis code for Kearns-Sayre syndrome, bilateral. Kearns-Sayre syndrome affecting both eyes, a rare inherited mitochondrial disorder causing progressive eye muscle weakness and other systemic complications. It belongs to the ICD-10-CM chapter for diseases of the eye and adnexa (h00-h59). H49.813 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. H49.813 is part of the FY2026 ICD-10-CM code set published by the CMS National Center for Health Statistics and used on Medicare, Medicaid, and commercial claims in the United States.

Yes. H49.813 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. H49.813 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

What is the V28 vs V24 difference for H49.813?

CMS phased in the V28 risk adjustment model over payment years 2024 (33%), 2025 (67%), and 2026 (100%), replacing V24. V28 consolidates HCC categories, removes some lower-acuity conditions, and recalibrates RAF weights across the entire model. H49.813 was a payment HCC under V24 (Other Significant Endocrine and Metabolic Disorders) but the V28 recalibration removed it from the risk adjustment model. Both models can still appear in legacy data and in payer-specific lookback periods.

What should coders know when reporting H49.813?

Confirm bilateral ocular involvement and genetic diagnosis are documented in the medical record Always code associated systemic manifestations including cardiac and auditory involvement with appropriate ICD-10 codes Because H49.813 maps to a payment HCC, the documentation must also satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's risk adjustment score.

H49.813 ICD-10 Code: Kearns-Sayre syndrome

ICD-10-CM Code View

HCC Buddy Code Card

Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.

Code lookupH49.813Effective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Diseases of the eye and adnexa (H00-H59) / Disorders of ocular muscles, binocular movement, accommodation and refraction (H49-H52)

H49.813

Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidance

Kearns-Sayre syndrome, bilateral

Kearns-Sayre syndrome affecting both eyes, a rare inherited mitochondrial disorder causing progressive eye muscle weakness and other systemic complications.

Buddy Insight

Kearns-Sayre syndrome is a rare mitochondrial myopathy characterized by progressive external ophthalmoplegia and pigmentary retinopathy, with onset before age 20.

CMS-HCC V28

Not risk-adjusted for this model/period.

RAF 0

CMS-HCC V24

Mapped

HCC 23

Other Significant Endocrine a...

RAF 0.230

ACA/HHS

Not risk-adjusted for this model/period.

RAF 0

ESRD/PACE

Mapped

HCC 23

Other Significant Endocrine a...

RAF 0.0

RXHCC

Mapped

HCC 43

Other Significant Endocrine a...

RAF 0.0

Code Trumping

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Code Book Path

Official

H49.8Other paralytic strabismus

H49.81Kearns-Sayre syndrome

H49.813Kearns-Sayre syndrome, bilateral

Inclusion Terms

Official

Progressive external ophthalmoplegia with pigmentary retinopathy

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for H49.813 in this effective period.

Related Child Codes

Official

H49.811Kearns-Sayre syndrome, right eye

H49.812Kearns-Sayre syndrome, left eye

H49.819Kearns-Sayre syndrome, unspecified eye

Includes

Official

ICD-10-CM does not list Includes notes for H49.813 in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for H49.813 in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for H49.813 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for H49.813 in this effective period.

Code Also

Official

, if applicable, other manifestations, such as:
heart block (I45.9)

Buddy Documentation Tip

HCC Buddy guidance

Laterality clearly specified as bilateral for the ocular manifestation

Documented diagnosis of Kearns-Sayre syndrome by a qualified provider

Evidence of progressive external ophthalmoplegia (ptosis, limited eye movement)

Evidence of pigmentary retinopathy on fundoscopic examination

MEAT Support

HCC Buddy guidance

Laterality clearly specified as bilateral for the ocular manifestation

Documented diagnosis of Kearns-Sayre syndrome by a qualified provider

Evidence of progressive external ophthalmoplegia (ptosis, limited eye movement)

Evidence of pigmentary retinopathy on fundoscopic examination

Audit Caution

HCC Buddy guidance

Coding only the ophthalmoplegia or retinopathy separately without recognizing the syndrome diagnosis

Failing to capture the systemic manifestations with additional codes (cardiac conduction defects, endocrine disorders)

Confusing Kearns-Sayre syndrome with chronic progressive external ophthalmoplegia (CPEO), which lacks retinopathy

Not documenting the mitochondrial etiology, which is important for genetic counseling and family screening

Common Mistakes

HCC Buddy guidance

H49.00-H49.03 — Third nerve palsy (isolated cranial nerve palsy, not progressive mitochondrial disease)

H49.10-H49.13 — Fourth nerve palsy (isolated palsy without systemic features)

H49.20-H49.23 — Sixth nerve palsy (isolated palsy without systemic features)

H49.881-H49.889 — Other paralytic strabismus (non-specific; use Kearns-Sayre code when syndrome is diagnosed)

Last updated: FY2026 ICD-10-CM Apr update, Apr 1, 2026 through Sep 30, 2026. CMS-HCC V28 is 100% phased in for payment year 2026.

Is H49.813 an HCC code?

Yes. H49.813 maps to Other Significant Endocrine and Metabolic Disorders under the V24 model but is not retained in V28.

HCC Category Mapping

V24HCC 23, Other Significant Endocrine and Metabolic Disorders

0.230

ESRDHCC 23, Other Significant Endocrine and Metabolic Disorders

0.000

RxHCCHCC 43, Other Significant Endocrine and Metabolic Disorders

0.000

RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.

MEAT Criteria for H49.813

For H49.813to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically, it has to be re-documented and supported each calendar year.

MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
EEvaluate: test results, medication response, or physical findings reviewed by the provider
AAssess: explicit mention in the assessment or plan with acknowledgment of status
TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis

Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed H49.813 during that encounter, not just copy-forwarded from a problem list.

What This Code Means

H49.813 is the ICD-10-CM diagnosis code for kearns-sayre syndrome, bilateral. Kearns-Sayre syndrome affecting both eyes, a rare inherited mitochondrial disorder causing progressive eye muscle weakness and other systemic complications. H49.813 sits in the ICD-10-CM chapter for diseases of the eye and adnexa (h00-h59), within the section covering disorders of ocular muscles, binocular movement, accommodation and refraction (h49-h52).

Under the older CMS-HCC V24 model, H49.813 maps to Other Significant Endocrine and Metabolic Disorders (HCC 23) with a community, non-dual, aged base RAF weight of 0.230. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.

Confirm bilateral ocular involvement and genetic diagnosis are documented in the medical record. Because H49.813 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for H49.813 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•Confirm bilateral ocular involvement and genetic diagnosis are documented in the medical record
•Always code associated systemic manifestations including cardiac and auditory involvement with appropriate ICD-10 codes

Clinical Significance

Kearns-Sayre syndrome is a rare mitochondrial myopathy characterized by progressive external ophthalmoplegia and pigmentary retinopathy, with onset before age 20. It can also involve cardiac conduction defects, cerebellar ataxia, and elevated cerebrospinal fluid protein. This is a multisystem disease with significant morbidity that warrants comprehensive risk adjustment capture given the complex, lifelong care needs.

Documentation Requirements

✓Laterality clearly specified as bilateral for the ocular manifestation
✓Documented diagnosis of Kearns-Sayre syndrome by a qualified provider
✓Evidence of progressive external ophthalmoplegia (ptosis, limited eye movement)
✓Evidence of pigmentary retinopathy on fundoscopic examination
✓Age of onset documented (typically before age 20)
✓Genetic testing or muscle biopsy results confirming mitochondrial DNA deletion if available
✓Cardiac evaluation results (ECG for conduction defects)
✓Documentation of any additional systemic manifestations (ataxia, hearing loss, endocrine dysfunction)

Commonly Confused Codes

•H49.00-H49.03 — Third nerve palsy (isolated cranial nerve palsy, not progressive mitochondrial disease)
•H49.10-H49.13 — Fourth nerve palsy (isolated palsy without systemic features)
•H49.20-H49.23 — Sixth nerve palsy (isolated palsy without systemic features)
•H49.881-H49.889 — Other paralytic strabismus (non-specific; use Kearns-Sayre code when syndrome is diagnosed)
•G71.0 — Muscular dystrophy (different category of myopathy; Kearns-Sayre is mitochondrial)
•H51.9 — Unspecified disorder of binocular movement (non-specific code that misses the underlying syndrome)