Quantitative assessment of CD30+ lymphocytes and eosinophils for the histopathological differential diagnosis of inflammatory bowel disease

Background and Aims: The histopathological discrimination of Crohn’s disease [CD] and ulcerative colitis [UC] can be challenging. The aim of this study was to evaluate if quantification of CD30+ lymphocytes and eosinophils in histopathological material improves the accuracy of diagnosis of inflammatory bowel disease. Methods: A total of 156 patients were diagnosed with IBD by a gastroenterologist and corroborated by 5 years of follow-up. Patients were treatment naïve at the time of biopsy. Samples were taken from diseased areas of the colon and examined by a gastrointestinal pathologist. Results: The median number of eosinophils in biopsies from affected segments was 42/high power field [hpf] [25.5–63.5] in CD and 98/hpf [67–123] in UC [p < 0.001]. Biopsies containing ≥ 70 eosinophils/hpf field had a sensitivity of 78.3% and a specificity of 71% for the diagnosis of UC ({area under the receiver operating characteristic (ROC) curve 0.767 (95% confidence interval [CI] 0.696–0.838)}. There was a median of three CD30+ cells/hpf [range 2–6] in diseased CD biopsies and 33 cells/hpf [24–52] in diseased UC biopsies [p < 0.001]. The cut-off determined by the ROC curve was 15 (sensitivity 97.4%, specificity 97.4%, positive likelihood ratio (PLR) 17.1, Negative likelihood ratio (NLR) 0.03, area under the curve [AUC]: 0.978; 95% CI 0.95310.999). Conclusions: Routine histopathological assessment with quantification of CD30+ cells is highly accurate at discriminating CD and UC. All the measured parameters are easy to perform, low-cost, and available in most pathological laboratories.