N11.0Nonobstructive reflux-associated chronic pyelonephritis

N11.0 is the ICD-10-CM diagnosis code for nonobstructive reflux-associated chronic pyelonephritis. It belongs to category N11 (chronic tubulo-interstitial nephritis), block N10-N16 (renal tubulo-interstitial diseases) and chapter 14 (diseases of the genitourinary system). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within N11 (chronic tubulo-interstitial nephritis), N11.0 is specifically for nonobstructive reflux-associated chronic pyelonephritis. Related codes cover chronic obstructive pyelonephritis (N11.1), other chronic tubulo-interstitial nephritis (N11.8) and unspecified (N11.9).

Don't report N11.0 together with the conditions in its Excludes1 note: vesicoureteral reflux NOS (N13.70).

Use an additional code (B95-B97), to identify infectious agent.

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 689 (Kidney and Urinary Tract Infections with MCC, relative weight 1.1415) and DRG 690 (Kidney and Urinary Tract Infections without MCC, relative weight 0.801), in MDC 11 (Diseases and Disorders of the Kidney and Urinary Tract), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 590.00 (chronic pyelonephritis without lesion of renal medullary necrosis) and 590.01 (chronic pyelonephritis with lesion of renal medullary necrosis).