ICD-10-CM 2027
ICD-10 code for rectum dilatation
From the official ICD-10-CM alphabetic index entry “Dilatation › rectum”. Page updated September 29, 2026.
About coding rectum dilatation
The ICD-10-CM code for rectum dilatation is K59.39 (Other megacolon).
Within K59.3, choose K59.39 (Other megacolon) only when documentation doesn't support a more specific option: toxic megacolon (K59.31).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
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.
Common questions about rectum dilatation ICD-10 codes
What is the ICD-10 code for rectum dilatation?
- K59.39 — Other megacolon.
Is K59.39 billable?
- Yes. K59.39 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can K59.39 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict K59.39 as a principal diagnosis.
Is K59.39 a CC or MCC?
- K59.39 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.