Towards the development of a non-bioptic diagnostic technique for eosinophilic esophagitis using Raman spectroscopy

Eosinophilic esophagitis (EoE) is believed to be a rare pathological condition that is characterized by dense infiltration of eosinophils in esophageal epithelial layer. Occurrence of this disease worldwide has started increasing rapidly in the last decade. Routine endoscopic observations can help in diagnosis only if clear longitudinal furrows or multiple concentric rings are observed but does not give any definitive conclusion in the early stages. Hence esophageal tissue samples are collected from multiple sites by biopsy and the number of eosinophils is counted after staining. Such a procedure is time consuming and has an inherent risk of bleeding, eventually damaging esophagus. Hence we developed a resonance Raman spectroscopy based approach to detect eosinophils in esophagus using mouse models. Our results show the presence of eosinophils in mice esophageal tissues suffering from inflammation by administering interleukin-33 while there are none in control mice. We believe this method can be used in clinical application for diagnosing EoE in the near future.