IBS is a very common diagnosis-of-exclusion that affects up to 20% of the population (3). That is to say that for everyone with a diagnosis of IBS the conventional, bio-mechanical approach has failed to identify the causal or contributory factors at work in that person. The result is that patients with IBS are usually left with symptom control as being the only treatment option.
Bio-mechanical Approach – Rome III Criteria
The bio-mechanical approach is implemented by applying the Rome III diagnostic pathway. The Rome Foundation is an international panel of gastro-enterologist and professional societies that reviews the worldwide evidence about diagnosis and treatment of gut disease and then sets globally agreed and implemented standards:
(1) In a patient with abdominal pain or distension that:
- started more than 6 months ago … and …
- has affected them at least 1 day per week for the last 3 months
(2) With at least 2 of the following features:
- symptoms improve after defaecation
- change in bowel frequency
- change in stool appearance
(3) And at least 2 of the following features:
- bloating, worse after eating
- distension, tenderness or hardness
- straining or urgency
- incomplete voiding
(4) After excluding “red flags”:
- family history of bowel or ovarian cancer
- unexpected weight loss
- rectal bleeding
- if over 55y old: 6 weeks of loose stool
- abdominal or rectal mass
- anaemia (FBC test)
- raised inflammatory markers (ESR & CRP tests)
(5) A diagnosis of IBS can be made:
- IBS with diarrhoea
- Mixed IBS
- IBS with constipation
The Rome Pathway is a reliable and reproducible approach that can be easily used by a Doctor to quickly assess a patient identifying those cases where organic disease is unlikely. Often a diagnosis can be made in a single, 10 minute consultation or at the second encounter after a round of tests.
Precision Lifestyle Medicine Approach
A different, precision lifestyle medicine approach that is informed by the exposome model can be considered as an extension of the Rome III.
(6) Detailed History – other Bio-mechanical causes & Lifestyle Factors
- medications
- other cancers
- colorectal & upper gastro-intestinal
- gynaecology & menstrual
- urology & renal
- endocrine
- vascular
- allergy and immunology
- mood & stress
(7) Further Investigations – in most cases
- blood: CA125, PSA, Iron Studies, Liver, Bone, B12, VitD, Glu, HbA1c
- stool: Occult Blood, Calprotectin, Helicobacter
- urine: MSU, Cytology
- radiology: Ultrasound Abdomen +/- Pelvis
(8) Lifestyle Medicine Tests – If above are normal
- Gut Biome
- Nutritional Profile
- Food Sensitivity
- SIBO Breath Test
This approach has uncovered previously undiagnosed disease in many patients, the examples include some “obvious” possibilities – colitis, prostate cancer, ovarian masses and cancers, gallstones – as well as some less common diagnoses – cholangiocarcinoma, Addisons Disease.
This approach has also uncovered “non-diagnostic” contributory factors in many patients. Even though there might not be an identifiable disease or condition, lifestyle advice or treatment can be given to reduce if not treat the IBS symptoms.