Eosinophilic esophagitis: What’s New!

Recently US FDA approved the Budesonide oral suspension formulation for adults and children above 11 years of age for treatment of eosinophilic esophagitis.

Eosinophilic esophagitis (EoE) is non-Ig-E mediated chronic immune mediated condition leading to esophageal dysfunction, food impaction and infiltration of the esophageal mucosa by eosinophils (≥ 15 eosinophils per high power field) without any other etiology attributing to it.¹ There is very limited data on EoE in pediatric population in India. Samanta A et al. conducted a cross sectional study at a tertiary care center to study the prevalence of EoE in Indian children undergoing upper gastrointestinal endoscopy and found that 3.5% children had EoE with male predominance and was seen associated with other atopic conditions.

Like other atopic conditions this disease is associated with T- helper type 2 cell immune responses. Th T- helper type 2 cell cytokines interleukin (IL) 4, IL-5, IL-13, and IL-33 are elevated which help in infiltration of esophageal mucosa with eosinophils leading to subepithelial fibrosis.² This is eventually responsible for symptoms in children and adolescents. Usual clinical presentation in such varies from vomiting, delay in growth, feeding difficulties in children to dysphagia, food impaction and abdominal pain in adolescents.

Coming to the diagnosis of EoE, endoscopy followed by histological assessment of the biopsy specimen is the main method. Other supportive tests like serum IgE levels and eosinophil levels in blood can be used too but are not confirmatory tests. The common endoscopic findings seen in EoE are linear furrows, edema, white plaques, piled circular rings, depletion of the subepithelial vascular patterns and occasionally strictures.³ In about 30% of the patients there could be normal endoscopic findings also.⁴ With the endoscopy procedure biopsy specimens are taken from several areas of esophagus and sent for histological evaluation. The major diagnostic criteria is at least 15 eosinophils/hpf in minimum one of the biopsy specimen. Further review of the eosinophil density, basal zone hyperplasia and other histologic findings.⁵

The treatment of EoE comprises of dietary management, medications and esophageal dilation. Dietary management involves following elimination diet and elemental diet. There are three types of elimination diet proposed- 1) Six food elimination diet (SFED) which consists of elimination of milk, soy, wheat, egg, peanuts and fish/shellfish, 2) Four food elimination diet (FFED) in which milk, egg, soy and wheat is avoided, and 3) Two-food elimination diet in which there is elimination of milk and wheat only.⁶ SFED is difficult to be followed in pediatric population though it provides best cure rates. A more favorable compliance was seen with FFED and there have been studies showing that fish/shellfish and peanuts are rare triggers for causing EoE, hence FFED is preferred initial diet.⁷ Elemental diet comprises of amino acid based formula and seems to be very effective dietary therapy but due to bad taste it is not used frequently.⁸ Proton pump inhibitors (PPI) are the first line of treatment due to reduction of acid production and anti-inflammatory activity.⁹ Topical glucocorticoids also have shown efficacy in treatment of EoE. Recently in March 2024 US Food and Drug Administration approved the use of Budesonide oral suspension formulation for adults and children above 11 years of age. This approval was informed by the clinical trials after seeing higher rates of histologic remission and symptomatic improvement in patients who were given oral budesonide versus the placebo, making it the preferred topical steroid for EoE.¹⁰ Many biologic agents such as dupilumab, mepolizumab and reslizumab have also been studied for treatment of EoE. A retrospective study done by Becker A. et al concluded that Dupilumab significantly improved the histologic findings seen in EoE and was seen to be well tolerated by pediatric populations also. However, there have been few studies which has quoted mixed results with these agents. Last treatment modality is esophageal dilation which is usually done in cases of patients with stricture who are symptomatic and are having dysphagia. But may be an initial treatment for patients with high grade strictures.¹¹

To conclude a wholesome approach is required for the diagnosis and treatment of EoE. The recent approval of budesonide and good results seen with Dupilumab will help in better outcome for patients with EoE, with dietary elimination playing essential role.

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