2027 ICD-10-CM Diagnosis Code D46.ZOther myelodysplastic syndromes
ICD-10-CM Codes›C00–D49›D37-D48›D46
- Billable — Valid for Submission
- Risk Adjusts — HCC 19
- Not Chronic
D46.Z is a billable ICD-10-CM diagnosis code for other myelodysplastic syndromes. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 811 through 812. Coders also document this condition as autosomal dominant aplasia and myelodysplasia. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Myelodysplastic syndrome (MDS).
For Medicare Advantage risk adjustment, D46.Z maps to CMS-HCC Category 19 (Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers) under the V28 model, adding a risk factor of about 1.798 for a community, non-dual, aged beneficiary in payment year 2027.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
D46.Z 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 2027.
Source: CMS Payment Year 2027 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.
- Autosomal dominant aplasia and myelodysplasia
- Complete deafness
- Congenital deafness
- Hypoplastic myelodysplastic syndrome
- Monosomy 7 syndrome
- Myelodysplastic neoplasm with biallelic TP53 inactivation
- Myelodysplastic neoplasm with low blasts and SF3B1 mutation
- Myelodysplastic syndrome with low blasts
- Unclassifiable myelodysplastic syndrome
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to D46.Z: its own notes plus those printed at D46, block D37-D48, and Chapter 2. A note printed at a category, block or chapter applies to every code under it.
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
- chronic myelomonocytic leukemia (C93.1-)
- neoplasms of unspecified behavior (D49.-)
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
Use Additional Code
Add a second code, after this one, to fully describe the condition.
Notes
General instructions on how these codes are used.
- Functional activity
- All neoplasms are classified in this chapter, whether they are functionally active or not. An additional code from Chapter 4 may be used, to identify functional activity associated with any neoplasm.
- Morphology [Histology]
- Chapter 2 classifies neoplasms primarily by site (topography), with broad groupings for behavior, malignant, in situ, benign, etc. The Table of Neoplasms should be used to identify the correct topography code. In a few cases, such as for malignant melanoma and certain neuroendocrine tumors, the morphology (histologic type) is included in the category and codes.
- Primary malignant neoplasms overlapping site boundaries
- A primary malignant neoplasm that overlaps two or more contiguous (next to each other) sites should be classified to the subcategory/code .8 ('overlapping lesion'), unless the combination is specifically indexed elsewhere. For multiple neoplasms of the same site that are not contiguous, such as tumors in different quadrants of the same breast, codes for each site should be assigned.
- Malignant neoplasm of ectopic tissue
- Malignant neoplasms of ectopic tissue are to be coded to the site mentioned, e.g., ectopic pancreatic malignant neoplasms are coded to pancreas, unspecified (C25.9).
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name D46.Z, its category, or a range that includes it.
Excludes1 2
These codes carry an Excludes1 note naming D46.Z: they are not reported together with it, unless the two conditions are unrelated.
Excludes2 1
These codes carry an Excludes2 note naming D46.Z: its condition is not part of those codes, and both may be reported when the patient has both.
Use Additional Code 1
These codes say to use an additional code from the note, and D46.Z is one of the codes named.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
specified NEC D46.Z
Myelodysplastic syndrome See Also: Syndrome, myelodysplastic; D46.9
specified NEC D46.Z
Syndrome See Also: Disease;
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Myelodysplastic Syndromes
clonal hematopoietic stem cell disorders characterized by dysplasia in one or more hematopoietic cell lineages. they predominantly affect patients over 60, are considered preleukemic conditions, and have high probability of transformation into acute myeloid leukemia.
Patient EducationClinical
Myelodysplastic Syndromes
Your bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. It contains immature cells, called stem cells. The stem cells can develop into the red blood cells that carry oxygen through your body, the white blood cells that fight infections, and the platelets that help with blood clotting.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert D46.Z to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About D46.ZOverview
What is the ICD-10 code for other myelodysplastic syndromes?
The ICD-10-CM code for other myelodysplastic syndromes is D46.Z (sometimes written as D46Z). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is D46.Z (Myelodysplastic syndromes) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report other myelodysplastic syndromes on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does D46.Z group to?
When other myelodysplastic syndromes is the principal diagnosis on an inpatient stay, it groups to MS-DRG 812, 811, with relative weights from 0.9237 to 1.3991 depending on complications. Higher weights mean higher Medicare reimbursement.
Can D46.Z be reported with a code from C93.1?
Not as a rule. The Excludes1 note on D46.Z lists "chronic myelomonocytic leukemia (C93.1-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).
Does D46.Z need an additional code?
When the condition applies, yes. The Use Additional Code note at D46, which applies to D46.Z, reads: code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5). The additional code is reported after D46.Z.
What HCC is D46.Z?
D46.Z (other myelodysplastic syndromes) maps to CMS-HCC Category 19 (Myelodysplastic Syndromes, Multiple Myeloma, and Other Cancers), commonly written as HCC 19, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. 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 19.
Does D46.Z risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, D46.Z adds a risk adjustment factor of about 1.798 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.957 to 1.989 depending on the payment segment). A more severe related category (HCC 17 and HCC 18) supersedes it when both are reported. See the full factor table on the HCC 19 category page.
