Coding and coverage · ICD-10-CM

K59

K59.3 Megacolon, not elsewhere classified

Not billable (header)Chapter 11

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Instructional notes

Chapter 11

Excludes2Not included here: the patient may have both; report both when both are present.
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

K59

Excludes1Not coded here: never report with this code, except when the two conditions are unrelated.
  • change in bowel habit NOS (R19.4)
  • intestinal malabsorption (K90.-)
  • psychogenic intestinal disorders (F45.8)
Excludes2Not included here: the patient may have both; report both when both are present.
  • functional disorders of stomach (K31.-)

This code

Excludes1Not coded here: never report with this code, except when the two conditions are unrelated.
  • congenital megacolon (aganglionic) (Q43.1)
  • megacolon (due to) (in) Chagas' disease (B57.32)
  • megacolon (due to) (in) Clostridium difficile (A04.7-)
  • megacolon (due to) (in) Hirschsprung's disease (Q43.1)
Code firstSequence the underlying condition first.
  • , if applicable (T51-T65) to identify toxic agent
Inclusion terms
  • Dilatation of colon

Chapter 11: Diseases of the digestive system · K55-K64 Other diseases of intestines (K55-K64)

Source: ICD-10-CM FY 2027 code descriptions and tabular list (CMS and CDC National Center for Health Statistics), effective 2026-10-01 through 2027-09-30 · CMS ICD-10 files. HCC mapping: CMS-HCC V28, payment year 2027. As of 2026-11-04.

Coverage and payment depend on the claim details; confirm with the Medicare Administrative Contractor.