2026 ICD-10-CM Diagnosis Code N28.84Pyelitis cystica

ICD-10-CM Codes›N00–N99›N25-N29›N28

ICD-10-CM N28.84
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

N28.84 is a billable ICD-10-CM diagnosis code for pyelitis cystica. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 689 through 690. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified diseases of kidney and ureters.

Code Identity

ICD-10-CM Code
N28.84
Billable Status
Yes — Valid for Submission
Code Describes
Pyelitis cystica
Short Description
Pyelitis cystica
Same as the full description in the CMS dataset.
Parent Code
N28.8
Other specified disorders of kidney and ureter

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN25-N29Other disorders of kidney and ureter
CategoryN28Other disorders of kidney and ureter, not elsewhere classified
This CodeN28.84Pyelitis cystica

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.

    • Pyelitis(congenital) (uremic)
      • cystica

Clinical ClassificationClinical

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

CCSR GEN006
Other specified and unspecified diseases of kidney and ureters
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Urine and Urination

Your kidneys make urine by filtering wastes and extra water from your blood. The waste is called urea. Your blood carries it to the kidneys. From the kidneys, urine travels down two thin tubes called ureters to the bladder. The bladder stores urine until you are ready to urinate.

Read the full article at MedlinePlus

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

Convert N28.84 to ICD-9-CMHistory

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

ICD-9-CM
590.3 Pyeloureteritis cystica
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 N28.84Overview

Is N28.84 (Other specified disorders of kidney and ureter) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report pyelitis cystica on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does N28.84 group to?

When pyelitis cystica is the principal diagnosis on an inpatient stay, it groups to MS-DRG 689, 690, with relative weights from 0.8095 to 1.1603 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of N28.84?

Under the General Equivalence Mappings, pyelitis cystica converts to ICD-9-CM 590.3 (pyeloureteritis cystica). 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.