N17-N19
Medium Complexity

Acute kidney failure and chronic kidney disease

Primary Specialty: Nephrology
Last Updated: 2025-09-10

ICD-10 Codes (12)

12 billable
0 category headers
N18
Billable
Chronic kidney disease (CKD)
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N18.1
Billable
Chronic kidney disease, stage 1
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N18.2
Billable
Chronic kidney disease, stage 2 (mild)
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N18.3
Billable
Chronic kidney disease, stage 3 (moderate)
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N18.30
Billable
Chronic kidney disease, stage 3 unspecified
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N18.31
Billable
Chronic kidney disease, stage 3a
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N18.32
Billable
Chronic kidney disease, stage 3b
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N18.4
Billable
Chronic kidney disease, stage 4 (severe)
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N18.5
Billable
Chronic kidney disease, stage 5
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N18.6
Billable
End stage renal disease
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N18.9
Billable
Chronic kidney disease, unspecified
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N19
Billable
Unspecified kidney failure
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Updates & Changes

FY 2026 Updates

Current Year

New Codes (2)

N18.30
Chronic kidney disease, stage 3a (GFR 45-59)
N18.31
Chronic kidney disease, stage 3b (GFR 30-44)

Revised Codes (1)

N18.6
End stage renal disease - updated to align with KDIGO guidelines

Deleted Codes(1)

N18.3
Chronic kidney disease, stage 3 (moderate) - replaced by more specific 3a/3b staging

Historical Changes

  • FY 2025: Routine maintenance updates with minor terminology clarifications
  • FY 2024: Enhanced specificity requirements for certain code ranges
  • FY 2023: Updated documentation guidelines for improved clarity

Upcoming Changes

  • Proposed updates pending review by Coordination and Maintenance Committee
  • Under consideration: Enhanced digital health integration codes

Implementation Guidance

  • Review all FY 2026 updates for N17-N19 codes before implementation
  • Always verify the most current codes in the ICD-10-CM manual
  • Ensure clinical documentation supports the selected diagnosis codes
  • +3 more guidance items...

Range Overview

high priority

The ICD-10 code range N17-N19 is dedicated to acute kidney failure and chronic kidney disease. These codes are used to classify and document different types and stages of kidney disease and failure, from acute renal failure due to shock (N17) to unspecified kidney failure (N19). The codes in this range are essential for accurate medical documentation and billing, and they provide crucial information for patient care, research, and public health reporting.

Key Usage Points:

  • Use N17 codes for acute kidney failure, specifying the cause if known.
  • N18 codes are used for chronic kidney disease (CKD), with subcategories indicating the stage of CKD.
  • N19 is used for unspecified kidney failure when the type or cause is not documented.
  • Always code to the highest level of specificity, using additional codes if necessary to identify any associated conditions or complications.
  • Remember to update the code if the patient's condition progresses from acute to chronic, or if the stage of CKD changes.

Coding Guidelines

When to Use:

  • When a patient is diagnosed with acute kidney failure due to shock or trauma.
  • When a patient has chronic kidney disease, regardless of the stage.
  • When a patient has kidney failure, but the type or cause is not specified.
  • When kidney disease or failure is a significant factor in the patient's current medical condition or treatment.
  • When documenting a patient's medical history that includes kidney disease or failure.

When NOT to Use:

  • When the patient has a kidney condition that is not classified as disease or failure.
  • When the patient has a history of kidney disease or failure, but it is not relevant to the current medical condition or treatment.
  • When the patient's kidney function is normal, even if there is a history of kidney disease or failure.
  • When the patient has a kidney transplant, use code Z94.0 instead.

Code Exclusions

Always verify exclusions in the patient's medical record and the latest ICD-10 coding guidelines.

Documentation Requirements

Accurate documentation for N17-N19 codes requires clear, specific information about the patient's kidney condition. This includes the type and cause of kidney disease or failure, the stage of chronic kidney disease, and any associated conditions or complications.

Clinical Information:

  • Type and cause of kidney disease or failure
  • Stage of chronic kidney disease
  • Associated conditions or complications
  • Relevant medical history
  • Current medical condition and treatment

Supporting Evidence:

  • Lab results showing kidney function
  • Imaging studies of the kidneys
  • Notes from nephrology consultations
  • Records of dialysis or other treatments for kidney disease or failure
Good Documentation Example:

Patient diagnosed with Stage 3 chronic kidney disease due to hypertension, with lab results confirming reduced kidney function.

Poor Documentation Example:

Patient has kidney problems.

Common Documentation Errors:

  • Not specifying the type or cause of kidney disease or failure
  • Not indicating the stage of chronic kidney disease
  • Not documenting associated conditions or complications
  • Not updating the code when the patient's condition changes

Range Statistics

3
Total Codes
12
Billable
Complexity:
Medium
Primary Use:Clinical Documentation
Chapter:14

Coding Complexity

Medium
Complexity Rating

Coding for kidney disease and failure is moderately complex due to the need for specificity in the type, cause, and stage of the condition, as well as the potential for associated conditions or complications. Coders must also stay up-to-date with the latest coding guidelines and exclusions.

Key Factors:
  • Determining the type and cause of kidney disease or failure
  • Identifying the stage of chronic kidney disease
  • Coding associated conditions or complications
  • Updating the code as the patient's condition changes
  • Navigating exclusions and other coding guidelines

Specialty Focus

N17-N19 codes are primarily used by nephrologists, but they are also relevant for internists, hospitalists, and any other providers treating patients with kidney disease or failure.

Primary Specialties:
Nephrology
60%
Internal Medicine
30%
Clinical Scenarios:
  • Patient with acute kidney failure due to septic shock
  • Patient with Stage 4 chronic kidney disease due to diabetes
  • Patient with kidney failure of unknown type or cause
  • Patient with chronic kidney disease and hypertension
  • Patient with history of acute kidney failure now recovered

Resources & References

Numerous resources are available to assist with coding for kidney disease and failure, including official ICD-10 guidelines, clinical reference materials, and educational resources for coders.

Official Guidelines:

  • ICD-10-CM Official Guidelines for Coding and Reporting
  • American Health Information Management Association (AHIMA) Coding Clinic
  • Centers for Medicare & Medicaid Services (CMS) ICD-10 Provider Resources

Clinical References:

  • National Kidney Foundation (NKF) Guidelines
  • American Society of Nephrology (ASN) Clinical Resources

Educational Materials:

  • AHIMA ICD-10 Training Materials
  • AAPC ICD-10 Coding Resources

Frequently Asked Questions

How do I code for a patient with chronic kidney disease and hypertension?

Use a code from the N18 range for the chronic kidney disease, and also code for the hypertension. If the hypertension is causing the kidney disease, use a code from the I12 or I13 range to indicate hypertensive kidney disease.

What if the type or cause of kidney failure is not specified in the medical record?

Use code N19 for unspecified kidney failure. However, always strive for the highest level of specificity in coding, and encourage providers to document the type and cause of kidney failure whenever possible.