ICD-10-CM Code K63.822: Megacolon in Diseases Classified Elsewhere
ICD-10-CM code K63.822 designates megacolon occurring as a manifestation of another underlying disease process that is classified elsewhere in the ICD-10 system. This is a secondary diagnosis code that requires documentation of the primary causative condition.
Code Structure and Classification
- K63.822 falls within the ICD-10-CM Chapter 11 (Diseases of the Digestive System), specifically under category K63 (Other diseases of intestine) 1
- The code is structured as: K63 (parent category) + .8 (other specified diseases of intestine) + 2 (second subcategory) + 2 (specific manifestation) 1
- This is a manifestation code that must be preceded by the underlying condition code in medical documentation 1
Clinical Context and Usage
- K63.822 should only be assigned when megacolon develops secondary to a separately classified disease entity, not as a primary diagnosis 1
- Common underlying conditions that may lead to coded megacolon include:
Documentation Requirements
- Medical records must clearly document both the megacolon and the underlying causative disease to support code assignment 1
- The primary disease code must appear first in the diagnostic sequence, followed by K63.822 as a secondary manifestation 1
- Clinical findings supporting megacolon diagnosis should include radiographic evidence (abdominal X-ray or CT showing colonic dilation >6 cm in the cecum or >12 cm in the transverse colon) or colonoscopic findings 1
Critical Coding Pitfalls
- Do not use K63.822 for toxic megacolon (use K59.31 instead), which represents an acute life-threatening complication requiring different clinical management 1
- Do not use K63.822 for congenital megacolon (Hirschsprung disease), which has its own specific Q43.1 code 1
- Failing to code the underlying disease first will result in improper sequencing and potential claim denials 1
- K63.822 cannot stand alone as a primary diagnosis—it requires a causative condition code 1