Current RMA Instruments

Changes from previous Instruments

ICD Coding

• ICD-9-CM Codes: 564.1
• ICD-10-AM Codes: K58

Brief description

Irritable bowel syndrome (IBS) is a common, functional gastrointestinal disorder, characterised by chronic abdominal pain and altered bowel habit, in the absence of any organic cause.

Confirming the diagnosis 

The diagnosis of IBS requires the fulfillment of symptom-based diagnostic criteria and an evaluation to exclude underlying organic disease.  There needs to be recurrent abdominal pain, on average, at least one day per week in the last three months, where the pain is associated with at least two of the following (1) defecation, (2) a change in stool frequency, or (3) a change in stool form (appearance).

Testing that is appropriate to the circumstances and presenting symptoms in the individual should be undertaken, to exclude organic disease (such as coeliac disease, diverticular disease, cancer or inflammatory bowel disease).  Any "alarm features" features such as rectal bleeding, unexplained weight loss, nocturnal or progressive pain signify a need for more extensive investigation, usually including endoscopy/colonoscopy.

The relevant medical specialist is a gastroenterologist.

Additional diagnoses covered by these SOPs

• Nil

Related conditions that may be covered by these SOPs (further information required)

• mucous colitis
• spastic colon
• spastic bowel

Conditions not covered by these SOPs

• inflammatory bowel disease*

* another SOP applies

Clinical onset

Once the diagnositc criteria in the SOP have been fulfilled the clinical onset can be backdated to when the relevant symptoms commenced.

Clinical worsening

Clinical worsening of IBS would be evidenced by an increase in the severity or frequency of symptoms.  The condition has a chronic course.  Symptoms can generally be controlled with diet or lifestyle modifications or medications.