P222 Delay in Meeting Diagnostic Criteria in Crohn's Disease.
G. Radford-Smith*1, E. Ferguson2, K. Hanigan3, L. Simms3, J. Irwin3
1Royal Brisbane and Women's Hospital, Gastroenterology, Brisbane, Australia, 2Royal Brisbane & Women's Hospital, Department of Gastroenterology, Brisbane, Australia, 3QIMR Berghofer Medical Research Institute, Complex Diseases, Brisbane, Australia
Defined diagnostic criteria for Crohn's disease (CD) use histological, clinical, radiological, surgical and endoscopic criteria. (1,2) These criteria may not be met until some time after initial presentation.
Aim: To study the delay between presentation and formal meeting of diagnostic criteria for CD using the Lennard Jones (LJ) and European Crohn's and Colitis Organisation (ECCO) consensus histological criteria.
Patients and Methods: All patients managed as longstanding CD at a tertiary referral centre (Brisbane, Australia) diagnosed between Jan 1st 1994 and March 1st 2008 were analyzed. All clinical, radiological, endoscopic, surgical, histological and laboratory data were recorded longitudinally. LJ criteria were considered met when 3 of the following criteria were present (2 if one was granuloma): typical location, discontinuous macroscopic disease, transmural ulceration, fibrosis, lymphocytic aggregation, and presence of granulomas. ECCO histological criteria were considered met when 3 of the following criteria (2 if one was granuloma) were present on mucosal biopsies or surgical specimens: lymphocytic infiltrate, crypt architectural distortion, irregular villous architecture (ileum), crypt abscesses, submucosal fibrosis, fissuring ulceration, and granulomas. Two further diagnostic models were analyzed; an extended LJ criteria requiring 3 of either the LJ criteria described above and three additional criteria (CRP>25mg/L, ASCA>25 units/mL and a family history of Crohn's disease), and a reduced LJ criteria requiring only two parameters. These were compared to the original LJ and ECCO criteria.
Results: 289 patients were analyzed, of whom 61.2% met LJ criteria within 1 year, and 76.7% within 5 years. Delay to meeting diagnostic criteria using LJ, ECCO, reduced LJ and extended LJ criteria is displayed in figures 1 and 2. The ECCO histological criteria were less sensitive than the LJ criteria in early identification of patients who eventually meet the LJ criteria. The extended LJ and reduced LJ criteria increased early identification of patients who eventually meet the original LJ criteria, however they also identify patients who never progress to meet LJ criteria.
Conclusion: There was a delay between presentation and diagnosis of greater than one year for 26% of CD patients who eventually met LJ diagnostic criteria. This highlights a need for new diagnostic criteria to identify these patients earlier in their disease course. This may be achieved by adding additional criteria to a diagnostic algorithm, or by reducing the number of existing criteria. However, these strategies would increase the number of patients with mild disease meeting diagnostic criteria, and need further study.