2026 ICD-10-CM Diagnosis Code N04.1Nephrotic syndrome with focal and segmental glomerular lesions

ICD-10-CM Codes›N00–N99›N00-N08›N04

ICD-10-CM N04.1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

N04.1 is a billable ICD-10-CM diagnosis code for nephrotic syndrome with focal and segmental glomerular lesions. 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 classical focal segmental glomerulosclerosis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nephritis; nephrosis; renal sclerosis.

Code Identity

ICD-10-CM Code
N04.1
Billable Status
Yes — Valid for Submission
Code Describes
Nephrotic syndrome with focal and segmental glomerular lesions
Short Description
Nephrotic syndrome w focal and segmental glomerular lesions
Parent Code
N04
Nephrotic syndrome

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN00-N08Glomerular diseases
CategoryN04Nephrotic syndrome
This CodeN04.1Nephrotic syndrome with focal and segmental glomerular lesions

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Classical focal segmental glomerulosclerosis
  • Congenital nephrotic syndrome with focal glomerulosclerosis
  • Focal segmental glomerulosclerosis
  • Hyperfiltration focal segmental glomerulosclerosis
  • Nephrotic syndrome, focal and segmental glomerular lesions

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Nephrotic syndrome with focal and segmental hyalinosis
  • Nephrotic syndrome with focal and segmental sclerosis
  • Nephrotic syndrome with focal glomerulonephritis

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.

    • Nephrosis, nephrotic(Epstein's) (syndrome) (congenital)
      • with
        • glomerular lesion
    • Syndrome
      • nephrotic (congenital)
        • with
          • focal and segmental glomerular lesions

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

  • Nephrosis, Lipoid

    a kidney disease with no or minimal histological glomerular changes on light microscopy and with no immune deposits. it is characterized by lipid accumulation in the epithelial cells of kidney tubules and in the urine. patients usually show nephrotic syndrome indicating the presence of proteinuria with accompanying edema.

  • Nephrotic Syndrome

    a condition characterized by severe proteinuria, greater than 3.5 g/day in an average adult. the substantial loss of protein in the urine results in complications such as hypoproteinemia; generalized edema; hypertension; and hyperlipidemias. diseases associated with nephrotic syndrome generally cause chronic kidney dysfunction.

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 N04.1 to ICD-9-CMHistory

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

ICD-9-CM
581.1 Epimembranous nephritis
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 N04.1Overview

Is N04.1 (Nephrotic syndrome) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report nephrotic syndrome with focal and segmental glomerular lesions on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does N04.1 group to?

When nephrotic syndrome with focal and segmental glomerular lesions 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 N04.1?

Under the General Equivalence Mappings, nephrotic syndrome with focal and segmental glomerular lesions converts to ICD-9-CM 581.1 (epimembranous nephritis). 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.