2027 ICD-10-CM Diagnosis Code N04.9Nephrotic syndrome with unspecified morphologic changes

ICD-10-CM Codes›N00–N99›N00-N08›N04

ICD-10-CM N04.9
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

N04.9 is a billable ICD-10-CM diagnosis code for nephrotic syndrome with unspecified morphologic changes. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 698 through 700. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 286 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nephritis; nephrosis; renal sclerosis.

N04.9 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model. It still risk-adjusts in the ESRD (V21) category 141 for payment year 2027.

Code Identity

ICD-10-CM Code
N04.9
Billable Status
Yes — Valid for Submission
Code Describes
Nephrotic syndrome with unspecified morphologic changes
Short Description
Nephrotic syndrome with unspecified morphologic changes
Same as the full description in the CMS dataset.
Parent Code
N04
Nephrotic syndrome

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN00-N08Glomerular diseases
CategoryN04Nephrotic syndrome
This CodeN04.9Nephrotic syndrome with unspecified morphologic changes

Medicare Risk Adjustment (HCC)Billing

N04.9 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model, but it maps to payment categories in the other CMS models shown below.

CMS-HCC V28 (Medicare Advantage Payment Model)
Not mapped
no payment category in the model that pays 100% of MA risk scores
Prior Model (CMS-HCC V24)
Not mapped under V24
this diagnosis newly risk-adjusts under the V28 model
Other CMS Models
ESRD (V21): HCC 141
ESRD V21 weights: 0.000 dialysis, 0.000 functioning graft
Part D (RxHCC)
Not mapped
N04.9 does not risk-adjust in the RxHCC prescription drug model

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute nephrotic syndrome
  • Amyloid nephropathy
  • Anasarca
  • Childhood nephrotic syndrome
  • Congenital hypoplasia of adrenal gland
  • Congenital nephrotic syndrome
  • Congenital nephrotic syndrome due to congenital infection
  • Congenital nephrotic syndrome, interstitial lung disease, epidermolysis bullosa syndrome
  • Disorder of kidney co-occurrent with human immunodeficiency virus infection
  • Familial steroid-resistant nephrotic syndrome with adrenal insufficiency
  • Familial steroid-resistant nephrotic syndrome with sensorineural deafness
  • Galloway Mowat syndrome
  • Genetic steroid-resistant nephrotic syndrome
  • Glomerular disease due to infectious disease
  • Glomerular disorder due to amyloidosis
  • Idiopathic steroid-resistant nephrotic syndrome
  • Idiopathic steroid-resistant nephrotic syndrome with sensitivity to intensified immunosuppression therapy
  • Idiopathic steroid-sensitive nephrotic syndrome with secondary steroid resistance
  • LAMB2-related infantile-onset nephrotic syndrome
  • Multi-drug resistant nephrotic syndrome
  • Nephrosis, deafness, urinary tract, digital malformation syndrome
  • Nephrotic syndrome
  • Nephrotic syndrome co-occurrent with human immunodeficiency virus infection
  • Nephrotic syndrome in amyloidosis
  • Nephrotic syndrome in malaria
  • Nephrotic syndrome in polyarteritis nodosa
  • Nephrotic syndrome secondary to glomerulonephritis
  • Nephrotic syndrome secondary to systemic disease
  • Nephrotic syndrome, deafness, pretibial epidermolysis bullosa syndrome
  • Nephrotic-nephritic syndrome
  • Pierson syndrome
  • Pulmonic stenosis and congenital nephrosis
  • Renal anasarca
  • Sporadic idiopathic steroid-resistant nephrotic syndrome
  • Steroid resistant nephrotic syndrome of childhood
  • Steroid sensitive nephrotic syndrome of childhood
  • Steroid-dependent nephrotic syndrome
  • Steroid-resistant nephrotic syndrome
  • Steroid-sensitive nephrotic syndrome

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to N04.9: its own notes plus those printed at N04, block N00-N08, and Chapter 14. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From N04 Nephrotic syndrome applies to 16 codes
  • congenital nephrotic syndrome
  • lipoid nephrosis

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From Block N00-N08 Glomerular diseases applies to 107 codes
  • hypertensive chronic kidney disease (I12.-)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 14 (N00-N99) Diseases of the genitourinary system applies to 838 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Code Also

A second code may be needed to fully describe the condition; the note gives no sequencing direction.

From Block N00-N08 Glomerular diseases applies to 107 codes
  • any associated kidney failure (N17-N19).

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name N04.9, its category, or a range that includes it.

Excludes1 1

These codes carry an Excludes1 note naming N04.9: they are not reported together with it, unless the two conditions are unrelated.

  • Q63 Other congenital malformations of kidney
    congenital nephrotic syndrome (N04.-) names N04.-, which includes this code

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

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

    pathological processes of the kidney without inflammatory or neoplastic components. nephrosis may be a primary disorder or secondary complication of other diseases. it is characterized by the nephrotic syndrome indicating the presence of proteinuria and hypoalbuminemia with accompanying edema.

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 N04.9 to ICD-9-CMHistory

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

ICD-9-CM
581.9 Nephrotic syndrome 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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About N04.9Overview

What is the ICD-10 code for nephrotic syndrome with unspecified morphologic changes?

The ICD-10-CM code for nephrotic syndrome with unspecified morphologic changes is N04.9 (sometimes written as N049). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is N04.9 (Nephrotic syndrome) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report nephrotic syndrome with unspecified morphologic changes on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does N04.9 group to?

When nephrotic syndrome with unspecified morphologic changes is the principal diagnosis on an inpatient stay, it groups to MS-DRG 699, 698, 700, with relative weights from 0.6740 to 1.6400 depending on complications. Higher weights mean higher Medicare reimbursement.

Is N04.9 a CC or MCC?

CMS lists N04.9 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 286 closely related codes in its exclusion list.

Can N04.9 be reported with a code from I12?

Not as a rule. The Excludes1 note at block N00-N08, which applies to N04.9, lists "hypertensive chronic kidney disease (I12.-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

Does N04.9 risk-adjust for Medicare Advantage payment?

Not for Medicare Advantage: N04.9 maps to no category in the CMS-HCC V28 model. It still risk-adjusts in the ESRD (V21) category 141 (Nephritis).