2027 ICD-10-CM Diagnosis Code R83.6Abnormal cytological findings in cerebrospinal fluid
ICD-10-CM Codes›R00–R99›R83-R89›R83
- Billable — Valid for Submission
- Not Chronic
R83.6 is a billable ICD-10-CM diagnosis code for abnormal cytological findings in cerebrospinal fluid. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 91 through 93. As a symptom code, it should not be used as a principal diagnosis once a related definitive diagnosis has been established. Coders also document this condition as abnormal cytological findings in CSF. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Abnormal findings without diagnosis.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Abnormal cytological findings in CSF
- Cerebrospinal fluid cell content - finding
- Cerebrospinal fluid cell content above reference range
- Cerebrospinal fluid lymphocytosis
- CSF: erythrocytosis
- CSF: polymorphonuclear leukocytosis
- Pleocytosis
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to R83.6: its own notes plus those printed at block R83-R89 and Chapter 18. 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.
- abnormal findings on antenatal screening of mother (O28.-)
- diagnostic abnormal findings classified elsewhere - see Alphabetical Index
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.
Notes
General instructions on how these codes are used.
- 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.
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Abnormal, abnormality, abnormalities See Also: Anomaly;
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Convert R83.6 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About R83.6Overview
What is the ICD-10 code for abnormal cytological findings in cerebrospinal fluid?
The ICD-10-CM code for abnormal cytological findings in cerebrospinal fluid is R83.6 (sometimes written as R836). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is R83.6 (Abnormal findings in cerebrospinal fluid) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report abnormal cytological findings in cerebrospinal fluid on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does R83.6 group to?
When abnormal cytological findings in cerebrospinal fluid is the principal diagnosis on an inpatient stay, it groups to MS-DRG 91, 92, 93, with relative weights from 0.7783 to 1.7050 depending on complications. Higher weights mean higher Medicare reimbursement.
Can R83.6 be a principal diagnosis?
Use it with care. This is a symptom code, so once a definitive diagnosis explaining the abnormal cytological findings in cerebrospinal fluid is established, that condition takes the principal position instead.
Can R83.6 be reported with a code from O28?
Not as a rule. The Excludes1 note at block R83-R89, which applies to R83.6, lists "abnormal findings on antenatal screening of mother (O28.-)". 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).
