HISTOLOGIC RESPONSE OR ENDOSCOPIC NORMALIZATION AFTER INTITIAL TREATMENT FOR EOSINOPHILIC ESOPHAGITIS IN CHILDREN LEADS TO LESS FIBROSTENOSIS OVER LONG-TERM FOLLOW-UP

Background: Untreated eosinophilic esophagitis (EoE) can result in development of fibrostenosis over time, but there are few data on whether successful treatment in childhood decreases this risk as children with EoE transition to adulthood.

Aim: To determine whether histologic response or endoscopic normalization after EoE treatment is associated with a decreased need for future esophageal dilation.

Methods: We conducted a retrospective cohort study of a large EoE database at an academic referral center. Subjects were included if they were <18 years old at diagnosis, diagnosed prior to 2018 (to allow for 5 years of follow-up), and were currently ≥18 years old or had ≥10 years of follow-up since diagnosis. Histologic response to any EoE therapy was defined as <15 eos/hpf; endoscopic normalization was defined as EREFS=0 (no findings). The outcome of fibrostenosis was defined to include esophageal stricture, narrowing, or dilation. We calculated the time from diagnosis to the first, second, and last follow-up endoscopy (EGD), as well as the time to fibrostenosis, if applicable. We assessed the proportion of histologic responders and normal endoscopies at the first, second, and last EGD, created Kaplan-Meier curves to assess time to fibrostenosis, and estimated hazard ratios using Cox proportional analysis.

Results: Among 166 patients included, mean ages at diagnosis and follow-up were 10.2 and 22.3 years. Over a mean follow-up time of 12.1±3.1 years, patients had an average of 4.3±4.2 EGDs. The mean time to first, second and last EGD after diagnosis was 358, 868, and 1724 days. The percent of patients on any EoE therapy at first, second, and last EGD was 94%, 90%, and 91%. The percent of patients with fibrostenosis was 9%, 15%, and 16% at first, second, and last EGD, a significant increase between first and last EGD (p=0.005). At the first, second, and last EGD, 42%, 45%, and 48% had histologic response and 27%, 30%, and 32% had endoscopic normalization. Patients with histologic response at second follow-up were significantly less likely to have fibrostenosis at the last EGD (p=0.02) (Table 1). We also found that patients with normal endoscopic findings at first follow-up were significantly less likely to have fibrostenosis at last EGD (p=0.04). Patients with histologic response at second follow-up developed fibrostenosis at a lower rate of than non-responders (HR=0.37, 95% CI 0.14-0.99) (Figure 1A), as did those with normal endoscopic findings at first follow-up (Figure 1B).

Conclusions: Histologic response and endoscopic normalization lead to lower rates of fibrostenosis in children with EoE. Though the development of fibrostenosis was relatively uncommon, occurring in <20% of children with EoE who were treated and followed long-term, it is reasonable to target treatment goals of histologic response and endoscopic normalization.