2026 ICD-10-CM Diagnosis Code P57.9Kernicterus, unspecified
ICD-10-CM Codes›P00–P96›P50-P61›P57
- Billable — Valid for Submission
- MCC — Major Complication or Comorbidity
- Risk Adjusts — HCC 192
- Not Chronic
P57.9 is a billable ICD-10-CM diagnosis code for kernicterus, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 791, 793. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 35 closely related codes. Coders also document this condition as acute bilirubin encephalopathy. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Hemolytic jaundice and perinatal jaundice.
For Medicare Advantage risk adjustment, P57.9 maps to CMS-HCC Category 192 (Cerebral Palsy, Except Quadriplegic) under the V28 model, adding a risk factor of about 0.314 for a community, non-dual, aged beneficiary in payment year 2026.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
P57.9 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2026.
Source: CMS Payment Year 2026 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Acute bilirubin encephalopathy
- Chronic bilirubin encephalopathy
- Kernicterus of newborn
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
nuclear, newborn See Also: Kernicterus of newborn; P57.9
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Kernicterus
a term used pathologically to describe bilirubin staining of the basal ganglia; brain stem; and cerebellum and clinically to describe a syndrome associated with hyperbilirubinemia. clinical features include athetosis, muscle spasticity or hypotonia, impaired vertical gaze, and deafness. nonconjugated bilirubin enters the brain and acts as a neurotoxin, often in association with conditions that impair the blood-brain barrier (e.g., sepsis). this condition occurs primarily in neonates (infant, newborn), but may rarely occur in adults. (menkes, textbook of child neurology, 5th ed, p613)
Patient EducationClinical
Jaundice
Jaundice causes your skin and the whites of your eyes to turn yellow. Too much bilirubin causes jaundice. Bilirubin is a yellow chemical in hemoglobin, the substance that carries oxygen in your red blood cells. As red blood cells break down, your body builds new cells to replace them. The old ones are processed by the liver.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert P57.9 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About P57.9Overview
What is the ICD-10 code for kernicterus, unspecified?
The ICD-10-CM code for kernicterus, unspecified is P57.9 (sometimes written as P579). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is P57.9 (Kernicterus) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report kernicterus, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does P57.9 group to?
When kernicterus, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 791, 793, with relative weights from 4.0590 to 4.1696 depending on complications. Higher weights mean higher Medicare reimbursement.
Is P57.9 a CC or MCC?
CMS lists P57.9 as an MCC (major complication or comorbidity) for FY 2026. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 35 closely related codes in its exclusion list.
What is the ICD-9 equivalent of P57.9?
Under the General Equivalence Mappings, kernicterus, unspecified converts to ICD-9-CM 774.7 (NB kernicterus). The mapping is approximate, so confirm the match fits the documentation.
What HCC is P57.9?
P57.9 (kernicterus, unspecified) maps to CMS-HCC Category 192 (Cerebral Palsy, Except Quadriplegic), commonly written as HCC 192, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2026. It does not map to any RxHCC in the Part D prescription drug model.
Does P57.9 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, P57.9 adds a risk adjustment factor of about 0.314 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.000 to 0.314 depending on the payment segment). A more severe related category (HCC 191) supersedes it when both are reported. See the full factor table on the HCC 192 category page.
