2026 ICD-10-CM Diagnosis Code R84.4Abnormal immunological findings in specimens from respiratory organs and thorax

ICD-10-CM Codes›R00–R99›R83-R89›R84

ICD-10-CM R84.4
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

R84.4 is a billable ICD-10-CM diagnosis code for abnormal immunological findings in specimens from respiratory organs and thorax. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 947 through 948. 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
R84.4
Billable Status
Yes — Valid for Submission
Code Describes
Abnormal immunological findings in specimens from respiratory organs and thorax
Short Description
Abnormal immunolog findings in specimens from resp org/thrx
Parent Code
R84
Abnormal findings in specimens from respiratory organs and thorax

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
CategoryR84Abnormal findings in specimens from respiratory organs and thorax
This CodeR84.4Abnormal immunological findings in specimens from respiratory organs and thorax

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
      • specimen
        • respiratory organs (bronchial washings) (nasal secretions) (pleural fluid) (sputum)
          • immunology

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 R84.4 to ICD-9-CMHistory

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

ICD-9-CM
792.9 Abn find-body subst NEC
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 R84.4Overview

Is R84.4 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report abnormal immunological findings in specimens from respiratory organs and thorax on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does R84.4 group to?

When abnormal immunological findings in specimens from respiratory organs and thorax is the principal diagnosis on an inpatient stay, it groups to MS-DRG 947, 948, with relative weights from 0.8005 to 1.2694 depending on complications. Higher weights mean higher Medicare reimbursement.

Can R84.4 be a principal diagnosis?

Use it with care. This is a symptom code, so once a definitive diagnosis explaining the abnormal immunological findings in specimens from respiratory organs and thorax is established, that condition takes the principal position instead.

What is the ICD-9 equivalent of R84.4?

Under the General Equivalence Mappings, abnormal immunological findings in specimens from respiratory organs and thorax converts to ICD-9-CM 792.9 (abn find-body subst NEC). 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.