Single-organ and Multisystem hypereosinophilic syndrome patients with gastrointestinal manifestations share common characteristics.

Abstract Background Eosinophilic gastrointestinal diseases (EGID) are defined by marked eosinophilia in the gastrointestinal (GI) tract resulting in a wide variety of GI symptoms. When accompanied by blood hypereosinophilia (HE; AEC≥1500/mm3), EGID can occur as an isolated GI disorder (HES/EGID overlap) or as part of a multisystem hypereosinophilic syndrome (Multisystem HES). Objective To describe the gastrointestinal disease of patients categorized as HES/EGID overlap versus those with Multisystem HES. Methods Consecutively enrolled patients on a natural history protocol to study eosinophilia with biopsy-proven EGID involving the esophagus, stomach, small-bowel and/or colon were evaluated for clinical, histopathologic, and endoscopic features by retrospective chart review. Results Among the 56 patients with EGID and HE, 34 were categorized as HES/EGID overlap and 22 as Multisystem HES. Demographics, GI symptoms and associated comorbidities were similar between the two groups. Multi-segment GI eosinophilia was present in 20/30(67%) patients who underwent tissue sampling of all four GI segments. Tissue eosinophilia in all four GI segments was found in 5/30(17%) patients. Dietary therapy was more common in HES/EGID overlap patients (65% vs. 23%, p=0.0028). Multisystem HES patients were more likely to receive glucocorticoids (100% vs. 79%, p=0.0349) and non-glucocorticoid systemic therapies (77% vs. 38%, p=0.0061). One-third (8/22) of Multisystem HES patients presented with isolated GI symptoms before developing extra-intestinal manifestations at a median of 1 year (range 0.25-15). Conclusion There are striking clinical similarities between Multisystem HES and HES/EGID overlap patients, despite differing treatment approaches. Moreover, Multisystem HES can present with isolated GI involvement. Larger prospective studies are needed to confirm these findings.