T52.4X4S ICD-10-CM Code: Toxic effect of ketones, undetermined, sequela
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FY 2026 Apr update / Injury, poisoning and certain other consequences of external causes (S00-T88) / Toxic effects of substances chiefly nonmedicinal as to source (T51-T65)
T52.4X4S
Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidanceToxic effect of ketones, undetermined, sequela
Toxic effect of ketones, undetermined, sequela
CMS-HCC V28
00
RAF 0
CMS-HCC V24
00
RAF 0
ACA/HHS
00
RAF 0
ESRD/PACE
00
RAF 0
RXHCC
00
RAF 0
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Code Book Path
Inclusion Terms
OfficialICD-10-CM does not list inclusion terms for T52.4X4S in this effective period.
Excludes 2
OfficialICD-10-CM does not list Excludes 2 notes for T52.4X4S in this effective period.
Related Child Codes
Includes
OfficialICD-10-CM does not list Includes notes for T52.4X4S in this effective period.
Excludes 1
OfficialICD-10-CM does not list Excludes 1 notes for T52.4X4S in this effective period.
Code First
OfficialICD-10-CM does not list Code First sequencing instructions for T52.4X4S in this effective period.
Use Additional
OfficialICD-10-CM does not list Use Additional Code instructions for T52.4X4S in this effective period.
Code Also
OfficialICD-10-CM does not list Code Also instructions for T52.4X4S in this effective period.
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 T52.4X4S an HCC code?
No. T52.4X4S 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
T52.4X4S is the ICD-10-CM diagnosis code for toxic effect of ketones, undetermined, sequela. T52.4X4S sits in the ICD-10-CM chapter for injury, poisoning and certain other consequences of external causes (s00-t88), within the section covering toxic effects of substances chiefly nonmedicinal as to source (t51-t65).
T52.4X4S 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.
T52.4X4S is a billable ICD-10-CM code that can be reported on claims but does not currently contribute to a Medicare Advantage member's RAF score under any CMS risk adjustment model (V28, V24, ESRD, or RxHCC). Coders reviewing T52.4X4S 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-impact RAF improvement available within accurate coding.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for T52.4X4S sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.