Coding and coverage · ICD-10-CM
Instructional notes
Chapter 18
Excludes2Not included here: the patient may have both; report both when both are present.
Notes
- 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.
Section R70-R79
Excludes2Not included here: the patient may have both; report both when both are present.
- abnormal findings on antenatal screening of mother (O28.-)
- abnormalities of lipids (E78.-)
- abnormalities of platelets and thrombocytes (D69.-)
- abnormalities of white blood cells classified elsewhere (D70-D72)
- coagulation hemorrhagic disorders (D65-D68)
- diagnostic abnormal findings classified elsewhere - see Alphabetical Index
- hemorrhagic and hematological disorders of newborn (P50-P61)
R79
Excludes1Not coded here: never report with this code, except when the two conditions are unrelated.
- asymptomatic hyperuricemia (E79.0)
- hypoglycemia NOS (E16.2)
- neonatal hypoglycemia (P70.3-P70.4)
- specific findings indicating disorder of amino-acid metabolism (E70-E72)
- specific findings indicating disorder of carbohydrate metabolism (E73-E74)
- specific findings indicating disorder of lipid metabolism (E75.-)
Excludes2Not included here: the patient may have both; report both when both are present.
- hyperglycemia NOS (R73.9)
Use additional codeAdd a second code for the full picture.
- code to identify any retained foreign body, if applicable (Z18.-)
This code
Excludes1Not coded here: never report with this code, except when the two conditions are unrelated.
- coagulation defects (D68.-)
Excludes2Not included here: the patient may have both; report both when both are present.
Inclusion terms
- Abnormal or prolonged bleeding time
- Abnormal or prolonged coagulation time
- Abnormal or prolonged partial thromboplastin time [PTT]
- Abnormal or prolonged prothrombin time [PT]
- Low von Willebrand factor
Chapter 18: Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified · R70-R79 Abnormal findings on examination of blood, without diagnosis (R70-R79)
Source: ICD-10-CM FY 2027 code descriptions and tabular list (CMS and CDC National Center for Health Statistics), effective 2026-10-01 through 2027-09-30 · CMS ICD-10 files. HCC mapping: CMS-HCC V28, payment year 2027. As of 2026-11-04.
Coverage and payment depend on the claim details; confirm with the Medicare Administrative Contractor.