ALOX15 and eosinophilic esophagitis: This is the case with 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE), a metabolite detected in peripheral blood derived from arachidonate 15-lipoxygenase (ALOX15), which is upregulated in the esophagus of EoE patients, and also found to be increased by 2.4-fold in the serum of EoE patients [164,165].