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Q87.86

Billable

Kleefstra syndrome

Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)

Is Q87.86 an HCC code?

No. Q87.86 is a billable ICD-10-CM code but does not map to any HCC category in V28, V24, ESRD, or RxHCC.

HCC Category Mapping

RxHCCHCC 148Mild Intellectual Disabilities
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 Q87.86

For Q87.86to 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 Q87.86 during that encounter — not just copy-forwarded from a problem list.

What This Code Means

Q87.86 is the ICD-10-CM diagnosis code for kleefstra syndrome. Kleefstra syndrome is a rare genetic disorder characterized by intellectual disability, developmental delay, distinctive facial features, and behavioral problems. Q87.86 sits in the ICD-10-CM chapter for congenital malformations, deformations, chromosomal abnormalities, and genetic disorders (q00-qa0), within the section covering other congenital malformations (q80-q89).

Q87.86 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

Maps to RxHCC 148 (Mild Intellectual Disabilities) with RAF weight 0.0 in the RxHCC model only. The condition does not impact CMS-HCC risk scores despite significant care coordination needs and lifelong support requirements. Coders reviewing Q87.86 should check whether additional documentation would support a more specific child code in the same hierarchy that does map to a payment HCC — capturing the correct specificity is the highest-leverage RAF improvement available within accurate coding.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for Q87.86 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

  • Document the severity of intellectual disability separately using F70-F79 codes
  • Note any associated behavioral or psychiatric manifestations for comprehensive coding

Clinical Significance

Kleefstra syndrome is a rare genetic disorder causing intellectual disability and developmental delays that require lifelong supportive care and monitoring. Early diagnosis enables appropriate interventions and family counseling while helping predict long-term care needs and resource allocation.

Documentation Requirements

  • Genetic testing confirming EHMT1 gene deletion or mutation
  • Documentation of intellectual disability level
  • Developmental milestone assessments
  • Behavioral evaluation findings
  • Characteristic facial features documentation
  • Speech and language assessment results
  • Cardiac evaluation (congenital heart defects common)
  • Neuropsychological testing results

Commonly Confused Codes

  • F79 — Unspecified intellectual disabilities (not genetic syndrome)
  • Q93.4 — Deletion of short arm of chromosome 9 (different genetic condition)
  • F84.0 — Autistic disorder (behavioral similarities but different etiology)
  • Q87.89 — Other specified congenital malformation syndromes

Code Hierarchy

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