E06.2
BillableChronic thyroiditis with transient thyrotoxicosis
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is E06.2 an HCC code?
No. E06.2 is a billable ICD-10-CM code but does not map to any HCC category in V28, V24, ESRD, or RxHCC.
HCC Category Mapping
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 E06.2
For E06.2to 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 E06.2 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
E06.2 is the ICD-10-CM diagnosis code for chronic thyroiditis with transient thyrotoxicosis. A chronic inflammatory thyroid condition where the patient experiences temporary periods of excess thyroid hormone production before settling into a hypothyroid state. E06.2 sits in the ICD-10-CM chapter for endocrine, nutritional and metabolic diseases (e00-e89), within the section covering disorders of thyroid gland (e00-e07).
E06.2 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 44 (Osteoporosis, Vertebral and Pathological Fractures) in the prescription drug model. This code does not map to CMS-HCC v28 or v24 models. The RxHCC mapping reflects the medication management required during thyrotoxic episodes and potential long-term thyroid replacement therapy.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for E06.2 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Capture both the chronic thyroiditis component and the transient thyrotoxicosis phase in documentation
- •Use additional codes to specify if patient is currently in thyrotoxic or hypothyroid phase
Clinical Significance
Chronic thyroiditis with transient thyrotoxicosis encompasses conditions where chronic thyroid inflammation intermittently releases stored thyroid hormone, causing temporary hyperthyroidism. This pattern is commonly seen in painless (silent) thyroiditis, postpartum thyroiditis, and Hashimoto's thyrotoxicosis (Hashitoxicosis). The transient nature distinguishes it from sustained thyrotoxicosis seen in Graves disease or toxic nodular goiter.
Documentation Requirements
- ✓Document the underlying chronic thyroiditis diagnosis, the episodic nature of thyrotoxic symptoms, thyroid function tests during the thyrotoxic episode, and thyroid antibody status.
- ✓Record the clinical context (e.g., postpartum period) and whether the patient returns to euthyroid or hypothyroid state between episodes.
Excludes 1 — Do NOT code together
- autoimmune thyroiditis (E06.3)
Commonly Confused Codes
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