Eosinophilic disorders of the gastro-intestinal tract: an update

Abstract

Eosinophilic diseases of the gastrointestinal tract, including eosinophilic esophagitis (EoE) and eosinophilic gastroenteritis (EGE), are rare chronic pathologies of the digestive system, with an immuno-mediated pathogenesis. Recent data suggest that, together with the "classic" IgE-response to allergens, also a delayed hypersensitivity mechanism could be involved in the development of eosinophilic disorders. EoE and EGE were studied only in the latest decades and as a consequence accurate data are not yet available, concerning not only pathogenesis, but also epidemiology, treatment and outcomes. The diagnosis of EoE is centered on endoscopic findings but the certainty is obtained by histological examination from biopsy samples, that has a sensitivity of 100% when based on five samples. The currently available treatments include topical corticosteroids, specific diets and endoscopic treatment. Concerning EGE, three subtypes (mucosal, muscular, and serosal) were identified. The diagnosis is based, as for EoE, on endoscopic and histological assessment, and the treatment includes pharmacological and dietetic approaches. Further studies are warranted in order to better define the etiology and pathogenesis of eosinophilic diseases of the gastrointestinal tract, and thus to develop more appropriate and specific therapies.

Keywords: Diagnosis; Eosinophilic esophagitis; Eosinophilic gastroenteritis; Pathogenesis; Therapy.

Fig. 1

EoE

Fig. 2

Hematoxylin-eosin, 20× magnification: Frustule of esophageal mucosa with diffuse infiltration of eosinophils (Eo > 20/HPF), microabscesses, disruption of the epithelial barrier

Fig. 3

Same sample of Fig. 2 in Giemsa, 20× magnification: diffuse eosinophilic infiltration with microabscesses, it can be appreciate also the intercellular edema and the acantholysis resulting from the eosinophils’ degranulation

Fig. 4

Eosinophilic gastroduodenitis, bulb mucosa

Fig. 5

Eosinophilic colitis