2026 ICD-10-CM Diagnosis Code S36.00XAUnspecified injury of spleen, initial encounter
S36.00XA is a billable ICD-10-CM diagnosis code for unspecified injury of spleen, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 814 through 816, 963 through 965. Coders also document this condition as closed injury of spleen. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Internal organ injury, initial encounter.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Closed injury of spleen
- Injury of spleen
- Injury of spleen during surgery
- Injury of spleen with open wound into abdominal cavity
- Injury of spleen without open wound into abdominal cavity
- Open injury of spleen
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Injury of intra-abdominal organs (S36). Use the following options for the applicable episode of care:
- A - initial encounter
- D - subsequent encounter
- S - sequela
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Spleen Diseases
Your spleen is an organ above your stomach and under your ribs on your left side. It is about as big as your fist. The spleen is part of your lymphatic system, which fights infection and keeps your body fluids in balance. It contains white blood cells that fight germs.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert S36.00XA to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S36.00XAOverview
Is S36.00XA (Unspecified injury of spleen) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report unspecified injury of spleen, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in S36.00XA mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for unspecified injury of spleen, such as an emergency visit or first evaluation.
What MS-DRG does S36.00XA group to?
When unspecified injury of spleen, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 814, 815, 816, 963, 964, 965, with relative weights from 0.6320 to 2.7338 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of S36.00XA?
Under the General Equivalence Mappings, unspecified injury of spleen, initial encounter converts to ICD-9-CM 865.00 (spleen injury NOS-closed). 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.
