Eosinophilic gastroenteritis: Imaging spectrum on intestinal ultrasonography and CT enterography.

Rationale And Objectives: Diagnostic delays are common in eosinophilic gastroenteritis (EGE). This study aimed to evaluate the value of imaging modalities in facilitating the diagnosis of EGE.

Materials And Methods: Patients diagnosed with EGE who underwent either intestinal ultrasound (IUS) or computer tomography enterography (CTE) were retrospectively recruited. Medical records were reviewed for clinical information, while IUS and CTE images were reviewed to summarize characteristic findings. Imaging characteristics of EGE subtypes were also evaluated.

Results: A total of 51 patients were included, with 30 undergoing IUS examinations and 42 undergoing CTE examinations. Positive findings were observed in 22 (73.3 %) patients on IUS and 32 (76.2 %) on CTE. In both modalities, the small intestine was the most commonly involved site (88.9 % on IUS and 90.6 % on CTE), with lesions predominantly diffuse (72.2 % on IUS and 75.0 % on CTE). IUS also revealed clear bowel wall stratification in 94.4 % of patients and identified a specific "piano key sign" in 22.2 % of patients. Thirty-six (70.6 %) patients were categorized into the mucosal subtype, 4 (7.8 %) muscular subtype, and 11 (21.6 %) serosal subtype. Most patients with the muscular and serosal subtypes exhibited typical manifestations (100 % and 81.8 %, respectively), while 63.9 % of patients with the mucosal subtype showed unremarkable or nonspecific imaging findings. No significant differences of baseline imaging characteristics were found between relieved and relapsed groups (P = 0.13).

Conclusion: Characteristic imaging findings of EGE include small intestine involvement, diffuse lesions, clear bowel wall stratification, and the "piano key sign". Imaging modalities can be useful tools to facilitate the diagnosis of EGE, especially for the muscular and serosal subtypes.