2026 ICD-10-CM Diagnosis Code D76.1Hemophagocytic lymphohistiocytosis
ICD-10-CM Codes›D50–D89›D70-D77›D76
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Risk Adjusts — HCC 115
- Chronic Condition
D76.1 is a billable ICD-10-CM diagnosis code for hemophagocytic lymphohistiocytosis. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 814 through 816. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 39 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Diseases of white blood cells.
For Medicare Advantage risk adjustment, D76.1 maps to CMS-HCC Category 115 (Specified Immunodeficiencies and White Blood Cell Disorders) under the V28 model, adding a risk factor of about 0.565 for a community, non-dual, aged beneficiary in payment year 2026.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
D76.1 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.
- Acquired hemophagocytic lymphohistiocytosis associated with malignant disease
- Acquired pancytopenia
- Disorder of hematopoietic system in newborn
- Familial hemophagocytic lymphohistiocytosis
- Hemophagocytic lymphohistiocytosis
- Lipochrome histiocytosis - familial
- Macrophage activation syndrome
- Macrophage activation syndrome due to juvenile systemic onset arthritis
- Malignant white blood cell disorder
- Neonatal anemia
- Neonatal thrombocytopenia
- NOCARH syndrome
- Secondary hemophagocytic lymphohistiocytosis
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Familial hemophagocytic reticulosis
- Histiocytoses of mononuclear phagocytes
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.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Syndrome See Also: Disease;
macrophage activation D76.1
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Macrophage Activation Syndrome
a serious complication of childhood systemic inflammatory disorders that is thought to be caused by excessive activation and proliferation of t-lymphocytes and macrophages. it is seen predominantly in children with systemic onset juvenile idiopathic arthritis.Grade 1 Secondary Hemophagocytic Lymphohistiocytosis, CTCAE
asymptomatic or mild symptoms; requiring clinical and/or diagnostic evaluation; intervention not indicatedGrade 2 Secondary Hemophagocytic Lymphohistiocytosis, CTCAE
moderate symptoms; intervention indicated (e.g., immunosuppressive agents)Grade 3 Secondary Hemophagocytic Lymphohistiocytosis, CTCAE
severe or medically significant but not immediately life threatening; hospitalization or prolongation of existing hospitalization indicatedGrade 4 Secondary Hemophagocytic Lymphohistiocytosis, CTCAE
life-threatening consequences; urgent intervention indicatedGrade 5 Secondary Hemophagocytic Lymphohistiocytosis, CTCAE
deathSecondary Hemophagocytic Lymphohistiocytosis, CTCAE
a disorder characterized by the development of a pathological and biochemical hyperinflammatory syndrome characterized by fever, cytopenias, hyperferritinemia, coagulopathy, hypofibrinogenemia and/or transaminitis and is attributable to therapy.Neonatal Alloimmune Thrombocytopenia|NAIT|Neonatal Thrombocytopenia due to Platelet Alloimmunization
thrombocytopenia that occurs in neonates as a consequence of transplacental passage of maternal alloantibodies directed against fetal platelet antigens.Neonatal Thrombocytopenia
a condition characterized by a decrease in the number of platelets in the blood below established reference ranges in a newborn.Secondary Hemophagocytic Lymphohistiocytosis
hemophagocytic lymphohistiocytosis due to infections, autoimmune disorders, or underlying malignancies. signs and symptoms include fever, lymphadenopathy, hepatomegaly, splenomegaly, and pancytopenia.Refractory Secondary Hemophagocytic Lymphohistiocytosis
secondary hemophagocytic lymphohistiocytosis that is resistant to treatment.
Patient EducationClinical
Familial hemophagocytic lymphohistiocytosis
Familial hemophagocytic lymphohistiocytosis is a disorder in which the immune system produces too many activated immune cells (lymphocytes) called T cells, natural killer cells, B cells, and macrophages (histiocytes). Excessive amounts of immune system proteins called cytokines are also produced.
Read the full article at MedlinePlus
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Convert D76.1 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About D76.1Overview
What is the ICD-10 code for hemophagocytic lymphohistiocytosis?
The ICD-10-CM code for hemophagocytic lymphohistiocytosis is D76.1 (sometimes written as D761). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is D76.1 a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report hemophagocytic lymphohistiocytosis on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does D76.1 group to?
When hemophagocytic lymphohistiocytosis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 814, 815, 816, with relative weights from 0.6320 to 2.1267 depending on complications. Higher weights mean higher Medicare reimbursement.
Is D76.1 a CC or MCC?
CMS lists D76.1 as a CC (complication or comorbidity) for FY 2026. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 39 closely related codes in its exclusion list.
What is the ICD-9 equivalent of D76.1?
Under the General Equivalence Mappings, hemophagocytic lymphohistiocytosis converts to ICD-9-CM 288.4 (hemophagocytic syndromes). The mapping is approximate, so confirm the match fits the documentation.
What HCC is D76.1?
D76.1 (hemophagocytic lymphohistiocytosis) maps to CMS-HCC Category 115 (Specified Immunodeficiencies and White Blood Cell Disorders), commonly written as HCC 115, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2026. It mapped to HCC 47 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. It does not map to any RxHCC in the Part D prescription drug model.
Does D76.1 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, D76.1 adds a risk adjustment factor of about 0.565 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.302 to 0.692 depending on the payment segment). A more severe related category (HCC 114) supersedes it when both are reported. See the full factor table on the HCC 115 category page.
