N18.31 Chronic kidney disease, stage 3a

Billable ICD-10-CM code, FY2026.

Applies from N18 Chronic kidney disease (CKD)

Code first

• any associated:
• diabetic chronic kidney disease (E08.22, E09.22, E10.22, E11.22, E13.22)
• hypertensive chronic kidney disease (I12.-, I13.-)

Use additional code

• code, if applicable, to identify:
• associated cachexia (E88.A)
• kidney transplant status (Z94.0)

Risk adjustment (HCC)

• CMS-HCC V28: HCC 329 — Chronic Kidney Disease, Moderate (Stage 3, Except 3B)
• ESRD V24: HCC 138

MS-DRG index

Defines the logic of DRG(s) 008 in MDC PRE.

Code annotations containing back-references to N18.31

Back-references to N18.3

• Use Additional: E08.22 Diabetes mellitus due to underlying condition with diabetic chronic kidney disease ("code to identify stage of chronic kidney disease (N18.1-N18.6)")
• Use Additional: E09.22 Drug or chemical induced diabetes mellitus with diabetic chronic kidney disease ("code to identify stage of chronic kidney disease (N18.1-N18.6)")
• Use Additional: E10.22 Type 1 diabetes mellitus with diabetic chronic kidney disease ("code to identify stage of chronic kidney disease (N18.1-N18.6)")
• Use Additional: E11.22 Type 2 diabetes mellitus with diabetic chronic kidney disease ("code to identify stage of chronic kidney disease (N18.1-N18.6)")
• Use Additional: E13.22 Other specified diabetes mellitus with diabetic chronic kidney disease ("code to identify stage of chronic kidney disease (N18.1-N18.6)")
• Use Additional: I12.9 Hypertensive chronic kidney disease with stage 1 through stage 4 chronic kidney disease, or unspecified chronic kidney disease ("code to identify the stage of chronic kidney disease (N18.1-N18.4, N18.9)")
• Use Additional: I13.0 Hypertensive heart and chronic kidney disease with heart failure and stage 1 through stage 4 chronic kidney disease, or unspecified chronic kidney disease ("code to identify stage of chronic kidney disease (N18.1-N18.4, N18.9)")
• Use Additional: I13.10 Hypertensive heart and chronic kidney disease without heart failure, with stage 1 through stage 4 chronic kidney disease, or unspecified chronic kidney disease ("code to identify the stage of chronic kidney disease (N18.1-N18.4, N18.9)")
• Use Additional: Q87.81 Alport syndrome ("code to identify stage of chronic kidney disease (N18.1-N18.6)")

Back-references to N18

• Code Also: D59.3 Hemolytic-uremic syndrome ("chronic kidney disease (N18.-)")
• Code First: D63.1 Anemia in chronic kidney disease ("underlying chronic kidney disease (CKD) (N18.-)")
• Code Also: E20.810 Autosomal dominant hypocalcemia ("chronic kidney disease (N18.-)")
• Code First: I5A Non-ischemic myocardial injury (non-traumatic) ("chronic kidney disease (CKD) (N18.-)")
• Use Additional: I75.81 Atheroembolism of kidney ("code for any associated acute kidney failure and chronic kidney disease (N17.-, N18.-)")
• Type 1 Excludes: N19 Unspecified kidney failure ("chronic kidney disease (N18.-)")

Diagnosis Index entries for N18.31

• Disease, diseased › kidney (functional) (pelvis) › chronic › stage 3a

Nearby codes

• N18 Chronic kidney disease (CKD)
• N18.1 Chronic kidney disease, stage 1
• N18.2 Chronic kidney disease, stage 2 (mild)
• N18.3 Chronic kidney disease, stage 3 (moderate)
• N18.30 Chronic kidney disease, stage 3 unspecified
• N18.31 Chronic kidney disease, stage 3a (this code)
• N18.32 Chronic kidney disease, stage 3b
• N18.4 Chronic kidney disease, stage 4 (severe)
• N18.5 Chronic kidney disease, stage 5
• N18.6 End stage renal disease
• N18.9 Chronic kidney disease, unspecified