N11 Chronic tubulo-interstitial nephritis

Category / Non-billable header 4 subcodes

Block: Renal tubulo-interstitial diseases (N10-N16)

Includes

  • chronic infectious interstitial nephritis
  • chronic pyelitis
  • chronic pyelonephritis

Use Additional Code

  • code (B95-B97), to identify infectious agent.

Subcodes

Subcodes are listed below for reference. Detail pages are not available for chapters 11–22.

Code Description Billable
N11..0 Nonobstructive reflux-associated chronic pyelonephritis Yes
N11..1 Chronic obstructive pyelonephritis Yes
N11..8 Other chronic tubulo-interstitial nephritis Yes
N11..9 Chronic tubulo-interstitial nephritis, unspecified Yes

Last reviewed: September 2026