N27 – Small kidney of unknown cause
ICD-10-CM 2027 diagnosis code · Other disorders of kidney and ureter
ICD-10-CM code
N27
- Code
N27(claims format:N27)- Description
- Small kidney of unknown cause
- Billable
- No – use a more specific code below
- Valid for
- Dates of service October 1, 2026 – September 30, 2027 (FY2027)
- Chapter
- 14. Diseases of the genitourinary system (N00-N99)
- Block
- N25-N29 Other disorders of kidney and ureter
Billable codes under N27
N27 is a header code and cannot be used on claims. Choose the most specific code:
- N27.0 – Small kidney, unilateralBillable
- N27.1 – Small kidney, bilateralBillable
- N27.9 – Small kidney, unspecifiedBillable
Notes for N27
Includes:
- oligonephronia
Notes inherited from parent codes
Instructional notes at a category or block level apply to every code below it.
Block N25-N29
Frequently asked questions
What is ICD-10 code N27?
N27 is the ICD-10-CM code for small kidney of unknown cause, in the block N25-N29 (Other disorders of kidney and ureter).
Is N27 a billable code?
No. N27 is a header code with more specific child codes; report one of the billable codes listed above.
Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.