Eosinophilic oesophagitis (EoE) is a condition in which the oesophagus (gullet) becomes inflamed as a result of an allergic reaction (see here).* The inflammation is caused by a type of white blood cell called eosinophils. The oesophagus transmits food from the mouth to the stomach, so the inflammation makes swallowing difficult as the oesophagus becomes narrower than usual. EoE is also associated with regurgitation, vomiting and reduced appetite.
EoE can only be reliably diagnosed on microscopic examination of a small piece of tissue which is removed from the oesophagus. This is done during a standard endoscopy examination. Treatment options include diet modification, oesophageal dilation and medicines, such as proton pump inhibitors and steroid creams.
As EoE is an allergic condition, it has been proposed that food allergy test could guide dietary modification advice, which aims to remove certain foods that might aggravate the oesophagus. The success of this approach is determined by follow-up endoscopies. Unfortunately, the process of eliminating the correct food item is somewhat hit-and-miss and this can be frustrating for many patients.
A recent prospective study by Philpott et al investigated the efficacy of allergy tests to help reduce the number of follow-up endoscopies a patient must undergo. The cohort consisted of EoE sufferers who are aged 18,
The study design involved histologically analysing the patients’ oesophagus following (a) withdrawal from corticosteroid therapy and (b) administration of 40mg esomeprazole twice daily for 8 weeks. EoE was diagnosed by a gastroenterologist. The patients were offered dietary modification therapy, in which they were told to exclude 6 food items from their diet. In successful cases, the patients were told to re-introduce single food items twice a day for two weeks before undergoing an endoscopy to see if EoE re-emerged.
The researchers also performed a number of allergy tests on the patients who underwent the “exclusion diet”, including but not limited to skin-prick and skin-patch tests to monitor for an allergic reaction to specific foods.
The results from the dietary exclusion component of the study were then matched with the results from the allergy test studies.
Unfortunately, the study failed to find any allergy test that accurately predicted which foods aggravated the oesophagus and caused EoE. As such, the mainstay method to determine which dietary exclusion plans are most effective remains endoscopy for now. Research continues, there is hope that a more amenable treatment option will be available in the near future!
* This blog is based on the article by Philpott et al. published in Aliment Pharmacol Ther. 2016;44(3):223-233