A Structured Approach to Colorectal Biopsy Assessment

August 1997


These practical notes supplement the "Guidelines for the initial biopsy diagnosis of suspected chronic inflammatory bowel disease. The British Society of Gastroenterology Initiative", published in the Journal of Clinical Pathology and circulated to members of the BSG. They are directed at histopathologists assessing colorectal biopsies for suspected intestinal inflammation, and provide a detailed, structured approach to routine biopsy assessment to extract maximum diagnostic information from biopsies. The colorectal mucosa has a limited repertoire of responses to injury, and the similarity of pathological changes in ulcerative colitis, Crohn's disease and other intestinal inflammation causes considerable diagnostic confusion and uncertainty. Effective management, however, depends on accurate clinico-pathological classification, and it is hoped by following the scheme adopted here errors can be minimised. The evidence-base, consensus development, clinical and histological principles have been presented in the Guidelines. This supplement draws heavily on detailed descriptions of CIIBD and its pathological mimics by many authors. Extensive references are included in the Guidelines and are not repeated here. The use of references and updating the structured approach through literature searching and critical review should be part of the routine practice of evidence-based pathology.

The structured approach provides five questions to be answered, four biopsy "compartments" to be examined, detailed checklists for answering the questions, and guides to assessment of the answers. The diagnostic value of the various histopathological features to be assessed follows the grading in the Guidelines.