2026 ICD-10-CM Diagnosis Code S37.021AMajor contusion of right kidney, initial encounter
S37.021A is a billable ICD-10-CM diagnosis code for major contusion of right kidney, 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 698 through 700, 963 through 965. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Internal organ injury, initial encounter.
Code Identity
Code Classification
Coding GuidelinesGuidance
The appropriate 7th character is to be added to each code from block Injury of urinary and pelvic organs (S37). 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
Kidney Diseases
You have two kidneys, each about the size of your fist. They are near the middle of your back, just below the rib cage. Inside each kidney there are about a million tiny structures called nephrons. They filter your blood. They remove wastes and extra water, which become urine. The urine flows through tubes called ureters.
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Convert S37.021A to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About S37.021AOverview
Is S37.021A (Major contusion of right kidney) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report major contusion of right kidney, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in S37.021A mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for major contusion of right kidney, such as an emergency visit or first evaluation.
What MS-DRG does S37.021A group to?
When major contusion of right kidney, initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 698, 699, 700, 963, 964, 965, with relative weights from 0.6899 to 2.7338 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of S37.021A?
Under the General Equivalence Mappings, major contusion of right kidney, initial encounter converts to ICD-9-CM 866.01 (kidney hematoma-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.
