Synopsis
Use reproducible clinical scores, biomarkers, endoscopy and cross-sectional imaging to distinguish symptoms from inflammation and make treatment changes against explicit, patient-relevant targets.
- IBD diagnosis is synthetic: symptoms, stool testing, endoscopy, histology and imaging establish chronic inflammation and distribution while excluding infection and alternative pathology.
- A clinical activity score standardises communication but is not a substitute for judgement; many scores include symptoms that anaemia, infection, bile-acid diarrhoea or irritable bowel physiology can reproduce.
- Use the same validated score longitudinally for the same question: Truelove and Witts for ASUC, partial Mayo or SCCAI for UC, and Harvey-Bradshaw or another agreed index for Crohn disease.
Key red flags
A severity score never overrules shock, peritonism, obstruction, major haemorrhage, toxic dilatation or sepsis; stabilise and image urgently.
Investigation priorities
Support diagnosis and track neutrophil-driven luminal inflammation non-invasively.
Management branches
New IBD is suspected or a transferred patient lacks a clear phenotype and objective baseline.
- Record symptoms using an agreed clinical index, but separately document weight, function, steroid exposure, perianal and extra-intestinal disease.
- Obtain infection tests, calprotectin, CRP, blood count, albumin, renal, liver, iron and phenotype-specific nutrition markers.