Outcomes of Serum Food-Specific Immunoglobulin G4 to Guide Elimination Diet in Patients With Eosinophilic Esophagitis
Amanda Lim, Benjamin Ngoi, Griffith B. Perkins, Stephanie Wong, Gail Whitelock, P. Hurtado, Andrew Ruszkiewicz, Thanh‐Thao Adriana Le, Pravin Hissaria, Nam Q. Nguyen
Abstract
INTRODUCTION: Eosinophilic esophagitis (EoE) is associated with atopy; however, recent studies have identified an association with food-specific immunoglobulin G 4 (FS-IgG 4 ) rather than immunoglobulin E antibodies. This study aimed to evaluate the role of serum FS-IgG 4 in guiding an elimination diet and its outcomes. METHODS: Patients with and without EoE were enrolled in a prospective, controlled, single tertiary center trial. Serum FS-IgG 4 titers, esophageal eosinophil counts, and dysphagia symptom questionnaire scores were assessed, and participants with elevated FS-IgG 4 (ImmunoCAP, cutoff of 10 mgA/L) commenced 6-week targeted elimination diet. Repeat serum FS-IgG 4 and endoscopic and histologic examination were performed at 6-week follow-up. RESULTS: Twenty-two patients with active EoE and 13 controls were recruited. Serum FS-IgG 4 to milk, wheat, soy, eggs, and nuts was significantly higher in EoE ( P = 0.0002, P = 0.002, P = 0.003, P = 0.012, and P < 0.001, respectively). Elevated serum FS-IgG 4 to 1 or more food groups (median 2) was identified in 21/22 (95.4%) patients with EoE; 20/21 underwent 6-week dietary elimination. Median reductions in dysphagia symptom questionnaire score and EoE endoscopic reference score after elimination were 8 ( P = 0.0007) and 1 ( P = 0.002), respectively. Nine (45%) patients had histological remission (<15 eosinophils per high-power field). Fall in median esophageal eosinophil count was not statistically significant (50 vs 23; P = 0.068). Serum FS-IgG 4 did not decline by 6-week follow-up. DISCUSSION: Serum FS-IgG 4 to milk, wheat, soy, egg, and nuts was present at higher levels in EoE, with targeted elimination resulting in 45% histologic remission rate. Serum FS-IgG 4 has potential as a noninvasive biomarker in EoE. When successful, FS-IgG 4 -led elimination diet can negate need for medications and be viewed more favorably by patients because of its smaller endoscopic burden compared with empirical elimination diets.