2026 ICD-10-CM Diagnosis Code D59.32Hereditary hemolytic-uremic syndrome
ICD-10-CM Codes›D50–D89›D55-D59›D59
- Billable — Valid for Submission
- MCC — Major Complication or Comorbidity
- Risk Adjusts — HCC 109
- Chronic Condition
D59.32 is a billable ICD-10-CM diagnosis code for hereditary hemolytic-uremic syndrome. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 791, 793, 811 through 812. 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 110 closely related codes. Coders also document this condition as congenital hemolytic uremic syndrome. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Hemolytic anemia.
For Medicare Advantage risk adjustment, D59.32 maps to CMS-HCC Category 109 (Acquired Hemolytic, Aplastic, and Sideroblastic Anemias) under the V28 model, adding a risk factor of about 1.144 for a community, non-dual, aged beneficiary in payment year 2026.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
D59.32 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.
- Congenital hemolytic uremic syndrome
- Hemolytic uremic syndrome with DGKE deficiency
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Atypical hemolytic uremic syndrome with an identified genetic cause
Code Also
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
A "code also" note instructs that two codes may be required to fully describe a condition, but this note does not provide sequencing direction.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Syndrome See Also: Disease;
genetic D59.32
hereditary D59.32
due to genetic disorder D59.32
familial D59.32
hereditary D59.32
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Kidney Diseases
You have two kidneys, each about the size of your fist. They are near the middle of your back, just below the rib cage. Inside each kidney there are about a million tiny structures called nephrons. They filter your blood. They remove wastes and extra water, which become urine. The urine flows through tubes called ureters.
Read the full article at MedlinePlus
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Code History & ChangesHistory
Replacement D59.32 replaces the following previously assigned code(s):
- D59.3 - Hemolytic-uremic syndrome
Questions About D59.32Overview
What is the ICD-10 code for hereditary hemolytic-uremic syndrome?
The ICD-10-CM code for hereditary hemolytic-uremic syndrome is D59.32 (sometimes written as D5932). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is D59.32 (Hemolytic-uremic syndrome) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report hereditary hemolytic-uremic syndrome on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does D59.32 group to?
When hereditary hemolytic-uremic syndrome is the principal diagnosis on an inpatient stay, it groups to MS-DRG 791, 793, 811, 812, with relative weights from 0.9182 to 4.1696 depending on complications. Higher weights mean higher Medicare reimbursement.
Is D59.32 a CC or MCC?
CMS lists D59.32 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 110 closely related codes in its exclusion list.
What HCC is D59.32?
D59.32 (hereditary hemolytic-uremic syndrome) maps to CMS-HCC Category 109 (Acquired Hemolytic, Aplastic, and Sideroblastic Anemias), commonly written as HCC 109, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2026. It mapped to HCC 46 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 96.
Does D59.32 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, D59.32 adds a risk adjustment factor of about 1.144 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.529 to 1.815 depending on the payment segment). HCC 109 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 109 category page.
