Eosinophilic Esophagitis due to Aeroallergens: A Systematic Review and Update.

Eosinophilic esophagitis is a chronic antigen-mediated esophageal disease characterized clinically by symptoms related to esophageal dysfunction and histologically by TH2 inflammation (at least 15 eosinophils/high power field) when other secondary systemic and local causes of esophageal eosinophilia are excluded. Although this disease was initially ascribed to a delayed reaction to food allergens, emerging evidence suggests that aeroallergens may also play a role in pathogenesis and disease course. Some studies support seasonal variations in the diagnosis of eosinophilic esophagitis and disease exacerbations owing to the increase in aeroallergens to which patients are sensitized. It is also known that this disease can be caused by extensive, identifiable exposure to aeroallergens and after treatment with specific immunotherapy based on food or aeroallergens. It was recently postulated that treatment of allergic rhinoconjunctivitis can improve the symptoms of eosinophilic esophagitis, although data are limited to case reports and small series. Currently, biomarkers and biologic therapies are not helpful for diagnosis or inducing clinical and histological remission of the disease. Nevertheless, there are high hopes for dupilumab. This review aims to give visibility to the involvement of aeroallergens in the triggering and exacerbation of eosinophilic esophagitis, since many of them, in addition to being airborne and inhalant, can also be ingested as food. Clearly, we must try to identify the cause of the disease to ensure remission.

Low Expression of ICAM-1 in Blood Eosinophils in Patients With Active Eosinophilic Esophagitis.

BACKGROUND AND OBJECTIVE: Eosinophilic esophagitis (EoE) is a chronic and isolated inflammation of the esophagus characterized by a marked infiltration of eosinophilic leukocytes. Diagnosis and course of the disease are based exclusively on histopathology. Therefore, patients must undergo several esophageal biopsies, implying a risk associated with the procedure and considerable use of resources. Objective: The presence of active circulating eosinophils, which are quantifiable through the expression of specific cellular activation proteins in their membrane, could be consistent with histopathological findings, which are currently the only valid parameters in studies on EoE. METHODS: The activity of peripheral blood eosinophils from patients with EoE was analyzed by identifying 5 surface molecules (CD69, IL- 5Rα, CD44, ICAM-1, CD63), which are seen to be expressed by the active eosinophils in flow cytometry. The results were compared with the infiltrate of eosinophils present in patients' esophageal biopsies. RESULTS: ICAM-1 levels decreased significantly in patients with active EoE compared with nonactive EoE patients, allergic patients, and healthy controls. In patients with EoE, an inverse correlation was observed between the number of eosinophils in the esophageal biopsy and the percentage of ICAM-1 expression in peripheral blood eosinophils. No differences were observed for the remaining molecules studied. CONCLUSION: Expression of ICAM-1 in blood eosinophils could be a useful noninvasive marker for the diagnosis and assessment of patients with EoE.

Eosinophilic Esophagitis: Demographic, Clinical, Endoscopic, Histologic, and Atopic Characteristics of Children and Teenagers in a Region in Central Spain.

BACKGROUND AND OBJECTIVE: Eosinophilic esophagitis (EoE) is an increasingly prevalent chronic inflammatory disease of the esophagus with an immunoallergic etiology. Few studies have been published on EoE in children and adolescents. The objective of this study was to analyze the demographic, clinical, serologic, endoscopic-histologic, and atopic characteristics of pediatric patients with EoE and to identify atopic and digestive comorbidities. METHODS: We conducted a prospective observational study in children and adolescents (<16 years) assessed in a specialized multidisciplinary EoE unit in a tertiary referral hospital in a central region of Spain between 2011 and 2015. RESULTS: Thirty-five patients were included in the study. Twenty-eight (80%) were male. The mean age was 9.6 years, 83% were atopic, and 28% reported a family history of atopy. The most common symptom was dysphagia (51%). Eosinophilia was detected in the blood of 60% of patients. Eosinophil cationic protein and total IgE were elevated in 88% and 77% of patients, respectively. The most frequent endoscopic finding was linear grooves (57%). Skin tests with aeroallergens were positive in 82% of patients (pollen 62% and food 60%). The main atopic comorbidities were asthma (48%) and rhinoconjunctivitis (37%). Digestive diseases were more often associated with gastritis and Helicobacter pylori infection (17%). CONCLUSIONS: Our results are similar to those previously reported. EoE is more common in boys and in individuals with a history of atopy and sensitization to airborne allergens and food. These results support the consideration of EoE as an atopic disease and underline the important role of allergists in early diagnosis and treatment.