AutoICD API

C91.4

Non-billable

Hairy cell leukemia

Hairy cell leukemia

This is a header/category code. For billing purposes, use a more specific child code from the list below.

Status

Non-billable / Header

Block

C81-C96

Parent Code

C91

Child Codes

3

ICD-11 Mapping

1 equivalent

Coding Notes

Inclusion Terms

Alternative clinical terms for this condition

  • Leukemic reticuloendotheliosis

Excludes 1

Codes that cannot be used together with this code (mutual exclusion)

Excludes 2

Conditions not included here, but the patient may have both

Child Codes (3)

C91.40

Hairy cell leukemia not having achieved remission

BillableC91.41

Hairy cell leukemia, in remission

BillableC91.42

Hairy cell leukemia, in relapse

Billable
Related Codes(8)
C91.0

Acute lymphoblastic leukemia [ALL]

C91.1

Chronic lymphocytic leukemia of B-cell type

C91.3

Prolymphocytic leukemia of B-cell type

C91.5

Adult T-cell lymphoma/leukemia (HTLV-1-associated)

C91.6

Prolymphocytic leukemia of T-cell type

C91.9

Lymphoid leukemia, unspecified

C91.A

Mature B-cell leukemia Burkitt-type

C91.Z

Other lymphoid leukemia

ICD-11 Equivalents(1)

ICD-11 Equivalents

View full mapping

Corresponding ICD-11 codes from the WHO crosswalk mapping

2A82.2Hairy-cell leukaemiaequivalentPrimary
Also Known As / Clinical Terms(31)

UMLS

Frequently Asked Questions
What is the ICD-10 code for hairy cell leukemia?

The ICD-10-CM code for hairy cell leukemia is C91.4. The full clinical description is "Hairy cell leukemia". C91.4 is a non-billable header code. Use a more specific child code for billing purposes.

What does ICD-10 code C91.4 mean?

ICD-10-CM code C91.4 represents “Hairy cell leukemia”. It is classified under Chapter 2: Neoplasms and is a non-billable header code. Use a more specific child code for billing purposes.

Is C91.4 a billable code?

No, C91.4 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 3 child codes under C91.4.

What chapter is C91.4 in?

C91.4 is in Chapter 2: Neoplasms (codes C00-D49).

What codes cannot be used with C91.4?

C91.4 has Excludes1 notes indicating codes that cannot be used together with it, including: personal history of leukemia (Z85.6).

What are the subcategories under C91.4?

C91.4 has 3 child codes, including: C91.40 (Hairy cell leukemia not having achieved remission), C91.41 (Hairy cell leukemia, in remission), C91.42 (Hairy cell leukemia, in relapse).

What are the UMLS CUIs for C91.4?

C91.4 is linked to 1 UMLS Concept Unique Identifier: C0023443. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.

How does C91.4 relate to ICF functioning codes?

ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like hairy cell leukemia affect a person's functioning — body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.

What is the ICD-11 equivalent of C91.4?

C91.4 maps to the ICD-11 code: 2A82.2 (Hairy-cell leukaemia).

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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.