Systematic review of histological remission criteria in eosinophilic esophagitis

Abstract

Elemental diets, dietary elimination, and steroid therapies are the most common therapies in the clinical trials for eosinophilic esophagitis (EoE). Histological findings (usually reported as eosinophils per microscopic high‐powered field [hpf]) remain the most common end‐point used to define response. Yet, the threshold for defining “response” and “remission” are ill‐defined among consensus guidelines and may vary from study to study. We conducted a systematic literature review of articles on eosinophilic esophagitis, published between January 2007 and November 2017, considering histological remission as the primary outcome. We abstracted treatment information and definitions of histological remission or response. A comparison of definitions of histological remission across and within institutions was performed. A total of 61 articles were included in this review, with approximately 60% of the studies published from centers in the United States. Histological definitions of remission of EoE ranged from 0 to ≤20 eosinophils/hpf. The most stringent criteria, ranging from 0 to ≤5 eosinophils/hpf, were commonly used in interventional trial studies that examined the effects of new treatments. We found remarkable variability in definitions between studies, treatment types, and regions. Age or epidemiological distribution of study subjects did not influence the criteria for histological remission. Clinical and histological improvements are important measures of the effects of treatment. Histological findings, the most objective measure of treatment, should provide an optimal method for comparing the effectiveness of various treatments. Yet, our findings suggest a lack of consistent remission criteria in published studies. Considering these inconsistencies, it is difficult to compare the effectiveness of various treatments.

A Conceptual Approach to Understanding Treatment Response in Eosinophilic Esophagitis

“…With such a range of outcomes, and with no consensus as of yet as to which outcomes are preferred, it is no surprise that there has been substantial variability in the literature. 26,127 As can be seen in Table 2, different measures have been selected in almost every randomized trial conducted; there is even more variability in observational and retrospective studies. At least 11 different histologic response thresholds have been reported as primary outcomes, with similarly divergent symptoms metrics.…”

A Clinical Perspective on the Dietary Therapies for Pediatric Eosinophilic Esophagitis: The Gap Between Research and Daily Practice

“…This required an esophagogastroduodenoscopy (EGD) at the beginning and at the end of the study, whereby the diagnosis of EoE was confirmed by an esophageal biopsy showing > 15 eos/HPF. The histological remission after the dietary treatment was defined as the actual accepted remission state at the time of publication of the study: initially considered as a reduction of the number of eosinophils in the esophageal biopsies and later on when the peak of the eosinophil count in the biopsy was below 15, 10 or 5 eos/HPF ( 8 ). The following dietary interventions were analyzed: elemental diet (ELED), allergy test-directed elimination diet, empirical 6-food elimination diet (6-FED), 4-food elimination diet (4-FED), two-food elimination diet (2-FED) and one-food elimination diet (1-FED).…”

Dietary Management of Eosinophilic Esophagitis: Tailoring the Approach

“…According to the latest guidelines [ 21 ], this corresponds to a persistent reduction of eosinophils to <15 eos/hpf in esophageal biopsies. However, a recent systematic review documented a high variability in the definition of histologic remission in studies regarding the treatment of EoE, ranging from 0 to ≤20 eos/hpf [ 28 ].…”