ICD-10-CM Codes
R00-R99
R50-R69
R50-
2023 ICD-10-CM Diagnosis Code R50.81

2023 ICD-10-CM Diagnosis Code R50.81

Fever presenting with conditions classified elsewhere

2016

2017

2018

2019

2020

2021

2022

2023

Billable/Specific Code

Manifestation Code

R50.81 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
The 2023 edition of ICD-10-CM R50.81 became effective on October 1, 2022.
This is the American ICD-10-CM version of R50.81 - other international versions of ICD-10 R50.81 may differ.

ICD-10-CM Coding Rules

R50.81 describes the manifestation of an underlying disease, not the disease itself.

Code First

Code First Help

Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation. In most cases the manifestation codes will have in the code title, "in diseases classified elsewhere." Codes with this title are a component of the etiology/manifestation convention. The code title indicates that it is a manifestation code. "In diseases classified elsewhere" codes are never permitted to be used as first listed or principle diagnosis codes. They must be used in conjunction with an underlying condition code and they must be listed following the underlying condition.

underlying condition when associated fever is present, such as with:
leukemia (
ICD-10-CM Diagnosis Code C91
Lymphoid leukemia
Type 1 Excludes
- personal history of leukemia (Z85.6)
C91
-
ICD-10-CM Diagnosis Code C95
Leukemia of unspecified cell type
Type 1 Excludes
- personal history of leukemia (Z85.6)
C95
)
neutropenia (
ICD-10-CM Diagnosis Code D70
- D70 Neutropenia
  - D70.0 Congenital agranulocytosis
  - D70.1 Agranulocytosis secondary to cancer chemother...
  - D70.2 Other drug-induced agranulocytosis
  - D70.3 Neutropenia due to infection
  - D70.4 Cyclic neutropenia
  - D70.8 Other neutropenia
  - D70.9 Neutropenia, unspecified
D70.-
)
sickle-cell disease (
ICD-10-CM Diagnosis Code D57
- D57 Sickle-cell disorders
  - D57.0 Hb-SS disease with crisis
    - D57.00 …… unspecified
    - D57.01 Hb-SS disease with acute chest syndrome
    - D57.02 Hb-SS disease with splenic sequestration
    - D57.03 Hb-SS disease with cerebral vascular involvem...
    - D57.09 Hb-SS disease with crisis with other specifie...
  - D57.1 Sickle-cell disease without crisis
  - D57.2 Sickle-cell/Hb-C disease
    - D57.20 …… without crisis
    - D57.21 Sickle-cell/Hb-C disease with crisis
      D57.211 Sickle-cell/Hb-C disease with acute chest syn...
      D57.212 Sickle-cell/Hb-C disease with splenic sequest...
      D57.213 Sickle-cell/Hb-C disease with cerebral vascul...
      D57.218 Sickle-cell/Hb-C disease with crisis with oth...
      D57.219 Sickle-cell/Hb-C disease with crisis, unspeci...
  - D57.3 Sickle-cell trait
  - D57.4 Sickle-cell thalassemia
    - D57.40 …… without crisis
    - D57.41 Sickle-cell thalassemia, unspecified, with cr...
      D57.411 Sickle-cell thalassemia, unspecified, with ac...
      D57.412 Sickle-cell thalassemia, unspecified, with sp...
      D57.413 Sickle-cell thalassemia, unspecified, with ce...
      D57.418 Sickle-cell thalassemia, unspecified, with cr...
      D57.419 Sickle-cell thalassemia, unspecified, with cr...
    - D57.42 Sickle-cell thalassemia beta zero without cri...
    - D57.43 Sickle-cell thalassemia beta zero with crisis...
      D57.431 Sickle-cell thalassemia beta zero with acute ...
      D57.432 Sickle-cell thalassemia beta zero with spleni...
      D57.433 Sickle-cell thalassemia beta zero with cerebr...
      D57.438 Sickle-cell thalassemia beta zero with crisis...
      D57.439 Sickle-cell thalassemia beta zero with crisis...
    - D57.44 Sickle-cell thalassemia beta plus without cri...
    - D57.45 Sickle-cell thalassemia beta plus with crisis...
      D57.451 Sickle-cell thalassemia beta plus with acute ...
      D57.452 Sickle-cell thalassemia beta plus with spleni...
      D57.453 Sickle-cell thalassemia beta plus with cerebr...
      D57.458 Sickle-cell thalassemia beta plus with crisis...
      D57.459 Sickle-cell thalassemia beta plus with crisis...
  - D57.8 Other sickle-cell disorders
    - D57.80 …… without crisis
    - D57.81 Other sickle-cell disorders with crisis
      D57.811 Other sickle-cell disorders with acute chest ...
      D57.812 Other sickle-cell disorders with splenic sequ...
      D57.813 Other sickle-cell disorders with cerebral vas...
      D57.818 Other sickle-cell disorders with crisis with ...
      D57.819 Other sickle-cell disorders with crisis, unsp...
D57.-
)

The following code(s) above R50.81 contain annotation back-references

Annotation Back-References

In this context, annotation back-references refer to codes that contain:

Applicable To annotations, or
Code Also annotations, or
Code First annotations, or
Excludes1 annotations, or
Excludes2 annotations, or
Includes annotations, or
Note annotations, or
Use Additional annotations

that may be applicable to R50.81:

R00-R99
2023 ICD-10-CM Range R00-R99
Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
Note
- This chapter includes symptoms, signs, abnormal results of clinical or other investigative procedures, and ill-defined conditions regarding which no diagnosis classifiable elsewhere is recorded.
- Signs and symptoms that point rather definitely to a given diagnosis have been assigned to a category in other chapters of the classification. In general, categories in this chapter include the less well-defined conditions and symptoms that, without the necessary study of the case to establish a final diagnosis, point perhaps equally to two or more diseases or to two or more systems of the body. Practically all categories in the chapter could be designated 'not otherwise specified', 'unknown etiology' or 'transient'. The Alphabetical Index should be consulted to determine which symptoms and signs are to be allocated here and which to other chapters. The residual subcategories, numbered .8, are generally provided for other relevant symptoms that cannot be allocated elsewhere in the classification.
- The conditions and signs or symptoms included in categories R00-R94 consist of:
- (a) cases for which no more specific diagnosis can be made even after all the facts bearing on the case have been investigated;
- (b) signs or symptoms existing at the time of initial encounter that proved to be transient and whose causes could not be determined;
- (c) provisional diagnosis in a patient who failed to return for further investigation or care;
- (d) cases referred elsewhere for investigation or treatment before the diagnosis was made;
- (e) cases in which a more precise diagnosis was not available for any other reason;
- (f) certain symptoms, for which supplementary information is provided, that represent important problems in medical care in their own right.
Type 2 Excludes
- abnormal findings on antenatal screening of mother (O28.-)
- certain conditions originating in the perinatal period (P04-P96)
- signs and symptoms classified in the body system chapters
- signs and symptoms of breast (N63, N64.5)
Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
R50
ICD-10-CM Diagnosis Code R50
Fever of other and unknown origin
Type 1 Excludes
- chills without fever (R68.83)
- febrile convulsions (R56.0-)
- fever of unknown origin during labor (O75.2)
- fever of unknown origin in newborn (P81.9)
- hypothermia due to illness (R68.0)
- malignant hyperthermia due to anesthesia (T88.3)
- puerperal pyrexia NOS (O86.4)
Fever of other and unknown origin

Approximate Synonyms

Febrile neutropenia
Fever presenting with other condition
Neutropenic fever
Periodic fever aphthous-stomatitis pharyngitis adenitis syndrome

ICD-10-CM R50.81 is grouped within Diagnostic Related Group(s) (MS-DRG v40.0):

864 Fever and inflammatory conditions

Convert R50.81 to ICD-9-CM

Code History

2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
2017 (effective 10/1/2016): No change
2018 (effective 10/1/2017): No change
2019 (effective 10/1/2018): No change
2020 (effective 10/1/2019): No change
2021 (effective 10/1/2020): No change
2022 (effective 10/1/2021): No change
2023 (effective 10/1/2022): No change

Code annotations containing back-references to R50.81:

Use Additional: D57
, D70

ICD-10-CM Diagnosis Code D57
Sickle-cell disorders
Type 1 Excludes
- other hemoglobinopathies (D58.-)
Use Additional
- code for any associated fever (R50.81)
ICD-10-CM Diagnosis Code D70
Neutropenia
Includes
- agranulocytosis
- decreased absolute neurophile count (ANC)
Type 1 Excludes
- neutropenic splenomegaly (D73.81)
- transient neonatal neutropenia (P61.5)
Use Additional
- code for any associated:
- fever (R50.81)
- mucositis (J34.81, K12.3-, K92.81, N76.81)

Diagnosis Index entries containing back-references to R50.81:

Fever (inanition) (of unknown origin) (persistent) (with chills) (with rigor) R50.9
ICD-10-CM Diagnosis Code R50.9
Fever, unspecified
Applicable To
Fever NOS
Fever of unknown origin [FUO]
Fever with chills
Fever with rigors
Hyperpyrexia NOS
Persistent fever
Pyrexia NOS
- due to
  - conditions classified elsewhere R50.81
- presenting with conditions classified elsewhere R50.81

ICD-10-CM Codes Adjacent To R50.81

R49.0 Dysphonia

R49.1 Aphonia

R49.2 Hypernasality and hyponasality

R49.21 Hypernasality

R49.22 Hyponasality

R49.8 Other voice and resonance disorders

R49.9 Unspecified voice and resonance disorder

R50 Fever of other and unknown origin

R50.2 Drug induced fever

R50.8 Other specified fever

R50.81 Fever presenting with conditions classified elsewhere

R50.82 Postprocedural fever

R50.83 Postvaccination fever

R50.84 Febrile nonhemolytic transfusion reaction

R50.9 Fever, unspecified

R51 Headache

R51.0 Headache with orthostatic component, not elsewhere classified

R51.9 Headache, unspecified

R52 Pain, unspecified

R53 Malaise and fatigue

R53.0 Neoplastic (malignant) related fatigue

Reimbursement claims with a date of service on or after October 1, 2015 require the use of ICD-10-CM codes.

2023 ICD-10-CM Diagnosis Code R50.81

Fever presenting with conditions classified elsewhere

Lymphoid leukemia

Leukemia of unspecified cell type

Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified

Fever of other and unknown origin

Sickle-cell disorders

Neutropenia

Fever, unspecified