A new eosinophilic esophagitis (EoE)-like disease without tissue eosinophilia found in EoE families.

BACKGROUND: Eosinophilic esophagitis (EoE) is a rapidly emerging, chronic inflammatory, genetically impacted disease of the esophagus, defined clinically by symptoms of esophageal dysfunction and, pathologically, by an eosinophil-predominant tissue infiltration. However, in four EoE families, we have identified patients presenting with EoE-typical and corticosteroid-responsive symptoms, but without tissue eosinophilia. The aim of this study was to clinically and immunologically characterize these patients with EoE-like disease. METHODS: Five patients suffering from an EoE-like disease were evaluated with endoscopic, histologic, functional, and quantitative immunohistological examinations, and mRNA expression determination. RESULTS: The frequency of first-generation offspring of patients affected by EoE or EoE-like disease was 40%. Immunofluorescence analysis confirmed an almost complete absence of eosinophils in the esophageal tissues of patients with EoE-like disease, but revealed a considerable T-cell infiltration, comparable to EoE. In contrast to EoE, eotaxin-3 mRNA and protein were markedly reduced in EoE-like disease (P < 0.05). The mRNA expression levels of three selected EoE genes (eotaxin-3, MUC4, and CDH26) allowed to discriminate between EoE-like disease, EoE, and normal epithelium. CONCLUSIONS: Patients suffering from 'EoE without eosinophilia' do not fulfill formally the diagnostic criteria for EoE. However, their clinical manifestation, immunohistology, and gene expression pattern, plus the fact that they bequeath EoE to their offspring, suggest a uniform underlying pathogenesis. Conventional EoE, with its prominent eosinophilia, therefore appears to be only one phenotype of a broader 'inflammatory dysphagia syndrome' spectrum. In this light, the role of the eosinophils, the definition of EoE, and its diagnostic criteria must likely be reconsidered.

Anti-eosinophil activity and clinical efficacy of the CRTH2 antagonist OC000459 in eosinophilic esophagitis.

BACKGROUND: Eosinophilic esophagitis (EoE) is a chronic, Th2-type inflammatory disease. Chemoattractant receptor-homologous molecule on Th2 cells (CRTH2) is a prostaglandin D(2) (PGD(2)) receptor, expressed by Th2 cells and other inflammatory cells, including eosinophils and basophils, that mediates chemotaxis and activation. OC000459 is a selective CRTH2 antagonist and would be expected to suppress eosinophilic tissue inflammation. The purpose of this study was to evaluate the efficacy and safety of an OC000459 monotherapy in adult patients with active, corticosteroid-dependent or corticosteroid-refractory EoE. METHODS: In this randomized, double-blind, placebo-controlled trial, 26 adult patients (m/f = 22/4; mean age 41 years, range 22-69 years) with active EoE, dependent or resistant to corticosteroids, were treated either with 100 mg OC000459 (n = 14) or placebo (n = 12) twice daily. Pre- and post-treatment disease activity was assessed clinically, endoscopically, histologically, and via biomarkers. The primary end point was the reduction in esophageal eosinophil infiltration. RESULTS: After an 8-week OC000459 treatment, the esophageal eosinophil load decreased significantly, from 114.83 to 73.26 eosinophils per high-power field [(eos/hpf), P = 0.0256], whereas no reduction was observed with placebo (102.80-99.47 eos/hpf, P = 0.870). With OC000459, the physician's global assessment of disease activity improved from 7.13 to 5.18 (P = 0.035). OC000459 likewise reduced extracellular deposits of eosinophil peroxidase and tenascin C, the effects not seen with placebo. No serious adverse events were observed. CONCLUSIONS: An 8-week treatment with the CRTH2-antagonist, OC000459, exerts modest, but significant, anti-eosinophil and beneficial clinical effects in adult patients with active, corticosteroid-dependent or corticosteroid-refractory EoE and is well tolerated.