Basics
ICD-10 Codes for Colostomy, Ileostomy and Urostomy: A Reference
Reference to ICD-10 status, encounter and complication codes for colostomy, ileostomy and urostomy, including national coding variants.
On this page
- How ICD-10 organises ostomy information
- Status codes (presence of a stoma)
- Colostomy and ileostomy
- Urostomy and other urinary openings
- Encounter codes for stoma care
- Complication codes
- Bowel stomas
- Urinary stomas
- Underlying conditions and procedure coding
- National editions and other systems
- Using codes in everyday care
- The bottom line
ICD-10 classifies the presence of a colostomy, ileostomy or urostomy, planned attention to that stoma, and many related complications. Status and encounter codes sit in chapter XXI (Z93 and Z43). Complication codes differ between the WHO ICD-10 and national clinical modifications such as ICD-10-CM. Exact codes depend on the edition used in your country; a clinician or clinical coder should apply the current local set.
How ICD-10 organises ostomy information
The International Classification of Diseases, Tenth Revision (ICD-10) is the World Health Organization system for coding diagnoses and reasons for contact with health services. It is not a treatment guideline. In clinical records an ostomy may appear as a current status, as the reason for an appointment, or as a complication such as stenosis, prolapse, haemorrhage or infection.
Chapter XXI (Z codes) covers factors influencing health status. Two families matter most for people living with a stoma: Z93 (artificial opening status) and Z43 (attention to artificial openings). Digestive-stoma complications are grouped with post-procedural disorders of the digestive system. Urinary-stoma complications sit with post-procedural disorders of the genitourinary system. The condition that led to surgery — inflammatory bowel disease, cancer, diverticular disease, bladder disease or a congenital anomaly — is coded in its own chapter.
Treat any public list, including this article, as orientation only. National clinical modifications add extra digits and are updated from time to time. If a code on a letter is unclear, ask your stoma care nurse or clinician, and let a trained clinical coder assign codes for official records.
Status codes (presence of a stoma)
Status codes record that an artificial opening exists. They do not, by themselves, describe whether the stoma is temporary or permanent, whether it is an end or a loop construction, or how the pouching system is managed.
Colostomy and ileostomy
In WHO ICD-10, Z93.3 is colostomy status and Z93.2 is ileostomy status. Z93.4 covers other artificial openings of the gastrointestinal tract. The same three-character stems appear in ICD-10-CM, the United States clinical modification, with the same meaning at this level of detail.
Coders choose ileostomy versus colostomy from the surgical anatomy, not from the look of the appliance. If a mucous fistula or a second bowel opening is still present, it may require an additional code.
Urostomy and other urinary openings
Urinary diversions are split. Z93.5 is cystostomy status (a surgically created opening into the bladder). Z93.6 is other artificial openings of the urinary tract, which is the usual category for an ileal conduit (urostomy) and related incontinent diversions that are not a simple cystostomy. ICD-10-CM further subdivides some cystostomy statuses, for example cutaneous vesicostomy and appendico-vesicostomy, while still using Z93.6 for other urinary openings.
Continent urinary reservoirs that have no external stoma may be classified differently. That distinction is a coding judgement, not something patients are expected to decide.
Encounter codes for stoma care
Z43 codes describe a contact whose purpose is attention to an artificial opening. Typical uses include education, routine review, or appliance issues that are not classified as a disease complication. In both WHO ICD-10 and ICD-10-CM the relevant stems are:
- Z43.3 — attention to colostomy
- Z43.2 — attention to ileostomy
- Z43.5 — attention to cystostomy
- Z43.6 — attention to other artificial openings of the urinary tract
- Z43.4 — attention to other artificial openings of the digestive tract
ICD-10-CM usually phrases these as an encounter for attention to the opening. They are not a substitute for complication codes when haemorrhage, infection or mechanical malfunction is the focus of care. Local coding standards decide which code is primary when several could apply.
Complication codes
Complication codes are used when the stoma itself is malfunctioning or injured, not merely present. Category names differ between the international ICD-10 and ICD-10-CM.
Bowel stomas
WHO ICD-10 uses K91.4 for colostomy and enterostomy malfunction, a relatively broad heading. ICD-10-CM instead uses K94.0- for colostomy complications and K94.1- for enterostomy complications, which is the usual family for ileostomy problems. Extra characters distinguish unspecified complication, haemorrhage, infection, malfunction and other specified complications.
Malfunction here is a coding term. Depending on the index and national guidance it may include stenosis, retraction, prolapse or related mechanical problems. It is not a do-it-yourself label for ordinary pouch leakage or sore skin. Peristomal skin conditions may be coded with dermatological categories according to local standards. Unexplained bleeding, fever, obstruction or a sudden change in output needs clinical assessment rather than self-coding.
Urinary stomas
WHO ICD-10 uses N99.5 for malfunction of a stoma of the urinary tract. ICD-10-CM expands the N99.5- block, with separate stems for cystostomy complications and for other urinary stomas. Later annual updates further distinguish incontinent external stomas from continent stomas and add characters for infection, haemorrhage, malfunction, hernia, stenosis and other specified problems.
These subcategories have changed between fiscal years, so a code on an older discharge summary may not match the current index. The official tabular list for the year of care is the reference, not a memorised public list.
Underlying conditions and procedure coding
ICD-10 codes for Crohn’s disease, ulcerative colitis, bowel or bladder cancer and other indications stay in their own chapters. They are not replaced by an ostomy status code. After cancer treatment, oncology coding rules may move the tumour into a personal-history category; a Z93 status code can still apply if the stoma remains.
Creation, revision or reversal of a stoma is a procedure, not a Z93 status. Procedure classification is a separate system: ICD-10-PCS in the United States, OPCS-4 in NHS hospitals in England, and other national schemes elsewhere. SNOMED CT, widely used in electronic records in the United Kingdom, contains detailed ostomy concepts that are mapped to ICD-10 for statistical reporting. A clinic letter may therefore show a SNOMED description rather than an ICD-10 code.
National editions and other systems
WHO publishes the international ICD-10. Many countries maintain a clinical modification. ICD-10-CM in the United States adds digits and ostomy-complication detail and is updated annually. Australia (ICD-10-AM) and Canada (ICD-10-CA) maintain their own indexes and standards. NHS hospital activity in England has long used WHO ICD-10 with national coding standards, alongside OPCS-4 for procedures.
ICD-11 is the WHO successor and reorganises some post-procedural chapters. Adoption is gradual and uneven. Until a country completes migration, ICD-10 or its modification remains the set on most ostomy-related administrative documents. Health-information professionals use the tabular list, alphabetic index and national standards in force for the date of the episode.
Using codes in everyday care
People with a stoma may meet ICD-10 codes on discharge summaries, clinic letters, insurance forms, disability applications and research registries. The code is a statistical label for that contact or that status. It does not grade quality of life, and it does not dictate which products a service may supply.
If a document appears to describe a complication you do not have, or omits a stoma you do have, raise it with the treating team or the health records department rather than altering codes yourself. Your stoma care nurse or clinician can explain the clinical wording; clinical coding staff can explain how that wording was classified.
The bottom line
For most people living with a bowel or urinary stoma, the core ICD-10 ideas are simple: Z93 records that the opening is present, Z43 records planned attention to it, and separate K or N codes are reserved for true stoma complications. International three-character stems are widely recognisable, but extra digits and some category names depend on your country and the year of the edition. Treat any public list as a map, not a personal code set, and ask your stoma care nurse, clinician or clinical coder before relying on a code for official paperwork.
Free guide
The New Ostomy Patient Guide
Everything for the first weeks with a stoma — pouching, skin care, diet, and getting back to daily life. Written with stoma care nurses. Free, by email.
Common questions
Frequently asked questions
- If my stoma has been reversed, will ostomy ICD-10 codes stay on my record?
- Past hospital episodes keep the codes that were correct at the time, so an old discharge summary may still show Z93 or a complication category. Once the opening has been closed, a current-status code should not describe a stoma that no longer exists; history of surgery is recorded differently. If a new clinic letter still lists an active colostomy, ileostomy or urostomy after reversal, ask your stoma care nurse, clinician or the health records department to review it.
- Why is an ileostomy complication listed as an enterostomy on a hospital bill?
- In ICD-10-CM, complications of a small-bowel stoma are grouped under enterostomy (K94.1-). Enterostomy is the broader anatomical term for an opening of the intestine, so an ileostomy problem is often classified there rather than under the word ileostomy. WHO ICD-10 instead uses a single heading, K91.4, for colostomy and enterostomy malfunction. The wording is a classification convention, not a sign that the wrong operation was recorded.
- Should I put an ICD-10 ostomy code on travel insurance or a medical ID?
- Plain language is usually clearer for emergency staff: the type of stoma, the date of surgery if known, and any medicines or allergies. Insurers and some agencies may later ask a clinician for a code, and the valid digits depend on the country and year of the code set. Self-assigned codes are easy to get wrong, especially between WHO ICD-10 and ICD-10-CM. Ask your stoma care nurse or clinician what wording they recommend before you submit official forms.
- How can I find which ICD-10 code was used for my hospital stay?
- In many health systems the codes appear on the discharge summary, an electronic patient record printout, or an itemised billing or activity statement. If they are missing, the hospital coding or health-records department can explain what was submitted for that episode. Clinic letters sometimes show a SNOMED CT description instead of ICD-10, which is normal in the United Kingdom. Your stoma care nurse or clinician can help interpret the clinical meaning; they may need the coding team for the exact characters.
References