2026 ICD-10-CM Diagnosis Code N03.AChronic nephritic syndrome with C3 glomerulonephritis
ICD-10-CM Codes›N00–N99›N00-N08›N03
- Billable — Valid for Submission
- Chronic Condition
N03.A is a billable ICD-10-CM diagnosis code for chronic nephritic syndrome with C3 glomerulonephritis. 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. Coders also document this condition as complement component 3 glomerulopathy. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nephritis; nephrosis; renal sclerosis.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Complement component 3 glomerulopathy
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Chronic nephritic syndrome with C3 glomerulopathy
Type 1 Excludes
- Chronic nephritic syndrome with C3 glomerulopathy with dense deposit disease N03.6
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
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.
- Nephritis, nephritic(albuminuric) (azotemic) (congenital) (disseminated) (epithelial) (familial) (focal) (granulomatous) (hemorrhagic) (infantile) (nonsuppurative, excretory) (uremic)
- chronic
- with
- C3
- glomerulonephritis
- Nephritis, nephritic(albuminuric) (azotemic) (congenital) (disseminated) (epithelial) (familial) (focal) (granulomatous) (hemorrhagic) (infantile) (nonsuppurative, excretory) (uremic)
- chronic
- with
- C3
- glomerulopathy
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Chronic Kidney Disease
You have two kidneys, each about the size of your fist. Their main job is to filter your blood. They remove wastes and extra water, which become urine. They also keep the body's chemicals balanced, help control blood pressure, and make hormones.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Code History & ChangesHistory
Replacement N03.A replaces the following previously assigned code(s):
- N03.8 - Chronic nephritic syndrome with other morphologic changes
Questions About N03.AOverview
Is N03.A (Chronic nephritic syndrome) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report chronic nephritic syndrome with C3 glomerulonephritis on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does N03.A group to?
When chronic nephritic syndrome with C3 glomerulonephritis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 698, 699, 700, with relative weights from 0.6899 to 1.6544 depending on complications. Higher weights mean higher Medicare reimbursement.
Footnotes
[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:
- The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
- The condition places limitations on self-care, independent living, and social interactions.
