2026 ICD-10-CM Diagnosis Code R19.33Right lower quadrant abdominal rigidity

ICD-10-CM Codes›R00–R99›R10-R19›R19

ICD-10-CM R19.33
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

R19.33 is a billable ICD-10-CM diagnosis code for right lower quadrant abdominal rigidity. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 393 through 395. 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 abdominal rigidity. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Abdominal pain and other digestive/abdomen signs and symptoms.

Code Identity

ICD-10-CM Code
R19.33
Billable Status
Yes — Valid for Submission
Code Describes
Right lower quadrant abdominal rigidity
Short Description
Right lower quadrant abdominal rigidity
Same as the full description in the CMS dataset.
Parent Code
R19.3
Abdominal rigidity

Code Classification

ChapterR00–R99Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
SectionR10-R19Symptoms and signs involving the digestive system and abdomen
CategoryR19Other symptoms and signs involving the digestive system and abdomen
This CodeR19.33Right lower quadrant abdominal rigidity

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Abdominal rigidity
  • Abdominal rigidity of right lower quadrant
  • Guarding of right iliac fossa
  • Guarding of right lumbar region

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.

    • Rigid, rigidity
      • abdominal
        • right lower quadrant

Clinical ClassificationClinical

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

CCSR SYM006
Abdominal pain and other digestive/abdomen signs and symptoms
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Abdominal Pain

Your abdomen extends from below your chest to your groin. Some people call it the stomach, but your abdomen contains many other important organs. Pain in the abdomen can come from any one of them. The pain may start somewhere else, such as your chest. Severe pain doesn't always mean a serious problem.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert R19.33 to ICD-9-CMHistory

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

ICD-9-CM
789.43 Abdmnal rgdt rt lwr quad
Exact Match The mapping is direct, with no qualifiers.

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 R19.33Overview

Is R19.33 (Abdominal rigidity) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report right lower quadrant abdominal rigidity on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does R19.33 group to?

When right lower quadrant abdominal rigidity is the principal diagnosis on an inpatient stay, it groups to MS-DRG 393, 394, 395, with relative weights from 0.6490 to 1.5993 depending on complications. Higher weights mean higher Medicare reimbursement.

Can R19.33 be a principal diagnosis?

Use it with care. This is a symptom code, so once a definitive diagnosis explaining the right lower quadrant abdominal rigidity is established, that condition takes the principal position instead.

What is the ICD-9 equivalent of R19.33?

Under the General Equivalence Mappings, right lower quadrant abdominal rigidity converts to ICD-9-CM 789.43 (abdmnal rgdt rt lwr quad). The mapping is a direct match.

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.