ICD-10-CM 2027
ICD-10 code for perirectal fistula
From the official ICD-10-CM alphabetic index entry “Fistula (cutaneous) › perirectal”. Page updated September 29, 2026.
About coding perirectal fistula
The ICD-10-CM code for perirectal fistula is K60.40 (Rectal fistula, unspecified). The official index lists 1 more specific code, so check the documentation for details such as type, cause, site or severity before settling on K60.40.
Within K60.4, choose K60.40 (unspecified) only when documentation doesn't support a more specific option: simple (K60.41) and complex (K60.42).
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 393 (Other Digestive System Diagnoses with MCC, relative weight 1.5881), DRG 394 (Other Digestive System Diagnoses with CC, relative weight 0.9228) and DRG 395 (Other Digestive System Diagnoses without CC/MCC, relative weight 0.6382), in MDC 06 (Diseases and Disorders of the Digestive System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific perirectal fistula codes (official index)
- tuberculous A18.32 — Tuberculous enteritis
Common questions about perirectal fistula ICD-10 codes
What is the ICD-10 code for perirectal fistula?
- K60.40 — Rectal fistula, unspecified. More specific codes apply when the documentation supports them: A18.32.
What is the ICD-10 code for tuberculous perirectal fistula?
- A18.32 — Tuberculous enteritis.
Is K60.40 billable?
- Yes. K60.40 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can K60.40 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict K60.40 as a principal diagnosis.
Is K60.40 a CC or MCC?
- No. K60.40 is neither a CC nor an MCC under MS-DRG v44.0.