2026 ICD-10-CM Diagnosis Code N03.9Chronic nephritic syndrome with unspecified morphologic changes

ICD-10-CM Codes›N00–N99›N00-N08›N03

ICD-10-CM N03.9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

N03.9 is a billable ICD-10-CM diagnosis code for chronic nephritic syndrome with unspecified morphologic changes. 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. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nephritis; nephrosis; renal sclerosis.

Code Identity

ICD-10-CM Code
N03.9
Billable Status
Yes — Valid for Submission
Code Describes
Chronic nephritic syndrome with unspecified morphologic changes
Short Description
Chronic nephritic syndrome with unsp morphologic changes
Parent Code
N03
Chronic nephritic syndrome

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN00-N08Glomerular diseases
CategoryN03Chronic nephritic syndrome
This CodeN03.9Chronic nephritic syndrome with unspecified morphologic changes

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Chronic diffuse glomerulonephritis
  • Chronic exudative glomerulonephritis
  • Chronic glomerulonephritis
  • Chronic nephritic syndrome
  • Chronic radiation nephritis
  • Complement component 3 glomerulonephritis
  • Complement component 3 glomerulopathy
  • Exudative glomerulonephritis
  • Exudative nephritis
  • Morphologic change of kidney due to chronic nephritic syndrome
  • Nephritic syndrome
  • Radiation nephritis
  • Secondary chronic nephritis

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.

    • Glomerulonephritis
      • chronic
    • Glomerulonephritis
      • latent or quiescent
    • Glomerulonephritis
      • poststreptococcal NEC
        • chronic
    • Nephritis, nephritic(albuminuric) (azotemic) (congenital) (disseminated) (epithelial) (familial) (focal) (granulomatous) (hemorrhagic) (infantile) (nonsuppurative, excretory) (uremic)
      • atrophic
    • Nephritis, nephritic(albuminuric) (azotemic) (congenital) (disseminated) (epithelial) (familial) (focal) (granulomatous) (hemorrhagic) (infantile) (nonsuppurative, excretory) (uremic)
      • chronic
    • Nephritis, nephritic(albuminuric) (azotemic) (congenital) (disseminated) (epithelial) (familial) (focal) (granulomatous) (hemorrhagic) (infantile) (nonsuppurative, excretory) (uremic)
      • poststreptococcal
        • chronic
    • Small(ness)
      • white kidney
    • Syndrome
      • nephritic
        • chronic
    • White
      • kidney, small

Clinical ClassificationClinical

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

CCSR GEN001
Nephritis; nephrosis; renal sclerosis
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Exudative Glomerulonephritis

    inflammation of the glomeruli with infiltration by polymorphonuclear leukocytes.

  • Chronic Glomerulonephritis

    a chronic, persistent inflammation of the glomeruli, which is slowly progressive, leading to impaired kidney function.

  • Chronic Glomerulonephritis with Lesion of Membranous Glomerulonephritis

    a slowly progressive inflammation of the glomeruli characterized by immune complex deposits on the epithelial side of the glomerular basement membrane.

  • Chronic Glomerulonephritis with Lesion of Proliferative Glomerulonephritis

    a slowly progressive inflammation of the glomeruli occurring status post infection with streptococcus.

  • Nephritic Syndrome

    a syndrome characterized by hematuria with dysmorphic red blood cells, red blood cell casts, and proteinuria; systemic manifestations may be present, including hypertension, edema, oliguria.

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.

Read the full article at MedlinePlus

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

Convert N03.9 to ICD-9-CMHistory

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

ICD-9-CM
582.9 Chronic nephritis NOS
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 N03.9Overview

Is N03.9 (Chronic nephritic syndrome) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report chronic nephritic syndrome with unspecified morphologic changes on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does N03.9 group to?

When chronic nephritic syndrome with unspecified morphologic changes 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.

What is the ICD-9 equivalent of N03.9?

Under the General Equivalence Mappings, chronic nephritic syndrome with unspecified morphologic changes converts to ICD-9-CM 582.9 (chronic nephritis NOS). The mapping is approximate, so confirm the match fits the documentation.

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.