Q99.819
BillableUsher syndrome, unspecified
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is Q99.819 an HCC code?
No. Q99.819 is a billable ICD-10-CM code but does not map to any HCC category in V28, V24, ESRD, or RxHCC.
This code does not map to an HCC category in any model (V28, V24, ESRD, RxHCC).
What This Code Means
Q99.819 is the ICD-10-CM diagnosis code for usher syndrome, unspecified. A genetic disorder causing progressive hearing loss and vision loss (retinitis pigmentosa), but the specific type or subtype cannot be determined. Q99.819 sits in the ICD-10-CM chapter for congenital malformations, deformations, chromosomal abnormalities, and genetic disorders (q00-qa0), within the section covering chromosomal abnormalities, not elsewhere classified (q90-q99).
Q99.819 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.
Use this code only when Usher syndrome is diagnosed but the type is not yet determined or documented.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for Q99.819 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Use this code only when Usher syndrome is diagnosed but the type is not yet determined or documented
- •Encourage documentation of genetic testing results and clinical features to allow for more specific coding in the future