Optimization of differential diagnosis of inflammatory bowel diseases based on an integrated assessment of oral mucosa status

Abstract

The objective of the investigation was to improve the differential diagnosis of inflammatory bowel diseases, on the basis of an integrated assessment of morphological data, the findings of optical imaging of tissues, and immunohistochemical examinations of the oral mucosa. Materials and Methods. We studied morphological and immunohistochemical characteristics of the oral mucosae in each of 26 patients with Crohn’s disease (CD) and 17 patients with ulcerative colitis (UC). We performed both visual comparisons and quantitative assessments of cross-polarization optical coherence tomography (CP OCT) images and morphological data on collagen fibers obtained from polarization microscopy using picrosirius red staining. Results. We suggest a new and objective differential diagnostic criterion for CD and UC which makes use of the condition of the oral mucosa, based on a quantitative assessment of CP OCT images (by calculation of the integral depolarization factor). In accordance with the results of immunohistochemical studies, we have revealed the most significant indices, and that these can be used as differential diagnostic criteria in CD and UC. We have developed a mathematical model including the four most immunohistochemical significant attributes (relative area of staining, the degree of CD16 expression, CD31 staining intensity and the degree of CD57 expression). We have determined a threshold level for the area of tryptase expression by the mast cells of the buccal mucosa, which achieves the maximum differential diagnostic accuracy for the CD and UC indices. The most significant characteristics of the immunohistochemical method exceed the diagnostic efficiency parameters of CP OCT. Conclusion. Given that CP OCT is non-invasive and has high diagnostic accuracy, we recommend using a quantitative assessment of CP OCT images as the first stage of an operational differential diagnosis of the diseases, based on the condition of the oral mucosa. In the case of inconclusive results, an oral mucosa biopsy, followed by morphological and immunohistochemical examination, would be expedient.