N23 vs N27
N23 (Unspecified renal colic) compared with N27 (Small kidney of unknown cause), from the official CMS tabular data. Both may be reported when both conditions are documented (Excludes2).
Can these codes be reported together?
Yes, when both are documented. N27 carries an Excludes2 note covering N23: “disorders of kidney and ureter with urolithiasis (N20-N23)”
Excludes2 marks distinct conditions — both may be reported when both are documented.
Side by side
| N23Unspecified renal colic | N27Small kidney of unknown cause | |
|---|---|---|
| Billing status | Billable | Non-billable header |
| Classification | N00-N99 — Diseases of the Genitourinary System (N00-N99) | N00-N99 — Diseases of the Genitourinary System (N00-N99) |
| Definition | Unspecified renal colic is a billable ICD-10-CM diagnosis code (N23). | Small kidney of unknown cause is a non-billable ICD-10-CM category code (N27). |
| Includes | — | oligonephronia |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources