2026 ICD-10-CM Diagnosis Code R83.8Other abnormal findings in cerebrospinal fluid

ICD-10-CM Codes›R00–R99›R83-R89›R83

ICD-10-CM R83.8
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

R83.8 is a billable ICD-10-CM diagnosis code for other abnormal findings in cerebrospinal fluid. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). As a symptom code, it should not be used as a principal diagnosis once a related definitive diagnosis has been established. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Abnormal findings without diagnosis.

Code Identity

ICD-10-CM Code
R83.8
Billable Status
Yes — Valid for Submission
Code Describes
Other abnormal findings in cerebrospinal fluid
Short Description
Other abnormal findings in cerebrospinal fluid
Same as the full description in the CMS dataset.
Parent Code
R83
Abnormal findings in cerebrospinal fluid

Code Classification

ChapterR00–R99Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
SectionR83-R89Abnormal findings on examination of other body fluids, substances and tissues, without diagnosis
CategoryR83Abnormal findings in cerebrospinal fluid
This CodeR83.8Other abnormal findings in cerebrospinal fluid

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Abnormal histological findings in CSF
  • Abnormal histology findings
  • AD7c neuronal thread protein concentration in cerebrospinal fluid above reference range
  • Cerebrospinal fluid appearance cloudy
  • Cerebrospinal fluid chloride above reference range
  • Cerebrospinal fluid chloride below reference range
  • Cerebrospinal fluid chloride outside reference range
  • Cerebrospinal fluid electrophoresis outside reference range
  • Cerebrospinal fluid globulin above reference range
  • Cerebrospinal fluid globulin below reference range
  • Cerebrospinal fluid glucose above reference range
  • Cerebrospinal fluid glucose below reference range
  • Color of fluid - finding
  • Color of specimen - finding
  • CSF appearance turbid
  • CSF appearance - finding
  • CSF appearance: blood-stained
  • CSF appearance: xanthochromia
  • CSF protein electrophoretic profile - finding
  • CSF: chloride level - finding
  • CSF: glucose level - finding
  • CSF: protein level - finding
  • Finding of cerebrospinal fluid: globulin level
  • Glucose level below reference range
  • Increased cerebrospinal fluid production
  • Increased cerebrospinal fluid production due to benign papilloma of choroid plexus
  • Increased cerebrospinal fluid production due to choroid plexus carcinoma
  • Increased cerebrospinal fluid production due to hyperplasia of choroid plexus
  • Presence of xanthochromia
  • Protein electrophoresis outside reference range
  • Protein in cerebrospinal fluid above reference range
  • Specimen xanthochromic

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Abnormal chromosomal findings in cerebrospinal fluid

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Abnormal, abnormality, abnormalities
      • cerebrospinal fluid
        • specified type NEC
    • Abnormal, abnormality, abnormalities
      • chromosome, chromosomal
        • analysis result
          • cerebrospinal fluid

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR SYM017
Abnormal findings without diagnosis
Default principal diagnosis: inpatient Yes · outpatient Yes

Convert R83.8 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
792.0 Abn fnd-cerebrospinal fl
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About R83.8Overview

Is R83.8 (Abnormal findings in cerebrospinal fluid) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other abnormal findings in cerebrospinal fluid on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Can R83.8 be a principal diagnosis?

Use it with care. This is a symptom code, so once a definitive diagnosis explaining the other abnormal findings in cerebrospinal fluid is established, that condition takes the principal position instead.

What is the ICD-9 equivalent of R83.8?

Under the General Equivalence Mappings, other abnormal findings in cerebrospinal fluid converts to ICD-9-CM 792.0 (abn fnd-cerebrospinal fl). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.