2027 ICD-10-CM Diagnosis Code N11.0Nonobstructive reflux-associated chronic pyelonephritis

ICD-10-CM Codes›N00–N99›N10-N16›N11

ICD-10-CM N11.0
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

N11.0 is a billable ICD-10-CM diagnosis code for nonobstructive reflux-associated chronic pyelonephritis. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 689 through 690. Coders also document this condition as chronic pyelonephritis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Urinary tract infections.

Code Identity

ICD-10-CM Code
N11.0
Billable Status
Yes — Valid for Submission
Code Describes
Nonobstructive reflux-associated chronic pyelonephritis
Short Description
Nonobstructive reflux-associated chronic pyelonephritis
Same as the full description in the CMS dataset.
Parent Code
N11
Chronic tubulo-interstitial nephritis

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN10-N16Renal tubulo-interstitial diseases
CategoryN11Chronic tubulo-interstitial nephritis
This CodeN11.0Nonobstructive reflux-associated chronic pyelonephritis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Chronic pyelonephritis
  • Chronic urinary tract infection
  • Familial non-obstructive reflux-associated chronic pyelonephritis
  • Non-obstructive reflux-associated chronic pyelonephritis
  • Pyelonephritis associated with another disorder

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to N11.0: its own notes plus those printed at N11, block N10-N16, 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 N11 Chronic tubulo-interstitial nephritis applies to 4 codes
  • chronic infectious interstitial nephritis
  • chronic pyelitis
  • chronic pyelonephritis
From Block N10-N16 Renal tubulo-interstitial diseases applies to 35 codes
  • pyelonephritis

Applicable To

Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.

  • Pyelonephritis (chronic) associated with (vesicoureteral) reflux

Excludes1

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

On N11.0 itself
  • vesicoureteral reflux NOS (N13.70)
From Block N10-N16 Renal tubulo-interstitial diseases applies to 35 codes
  • pyeloureteritis cystica (N28.85)

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)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From N11 Chronic tubulo-interstitial nephritis applies to 4 codes
  • code (B95-B97), to identify infectious agent.

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

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name N11.0, its category, or a range that includes it.

Excludes1 2

These codes carry an Excludes1 note naming N11.0: they are not reported together with it, unless the two conditions are unrelated.

  • N13.7 Vesicoureteral-reflux
    reflux-associated pyelonephritis (N11.0)
  • N03 Chronic nephritic syndrome
    chronic tubulo-interstitial nephritis (N11.-) names N11.-, 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 GEN004
Urinary tract infections
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Urinary Tract Infections

The urinary system is the body's drainage system for removing wastes and extra water. It includes two kidneys, two ureters, a bladder, and a urethra. Urinary tract infections (UTIs) are the second most common type of infection in the body.

Read the full article at MedlinePlus

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

Convert N11.0 to ICD-9-CMHistory

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

ICD-9-CM
590.00 Chr pyelonephritis NOS
Approximate The match is approximate rather than exact.
ICD-9-CM
590.01 Chr pyeloneph w med necr
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 N11.0Overview

What is the ICD-10 code for nonobstructive reflux-associated chronic pyelonephritis?

The ICD-10-CM code for nonobstructive reflux-associated chronic pyelonephritis is N11.0 (sometimes written as N110). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is N11.0 (Chronic tubulo-interstitial nephritis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report nonobstructive reflux-associated chronic pyelonephritis on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does N11.0 group to?

When nonobstructive reflux-associated chronic pyelonephritis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 689, 690, with relative weights from 0.8008 to 1.1415 depending on complications. Higher weights mean higher Medicare reimbursement.

Can N11.0 be reported with N13.70?

Not as a rule. The Excludes1 note on N11.0 lists "vesicoureteral reflux NOS (N13.70)". 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 N11.0 need an additional code?

When the condition applies, yes. The Use Additional Code note at N11, which applies to N11.0, reads: code (B95-B97), to identify infectious agent.. The additional code is reported after N11.0.