Eosinophilic Gastroenteritis with Eosinophilic Dermatitis

Eosinophilic gastroenteritis (EG) is characterized by eosinophilic infiltration of the bowel wall and variable gastrointestinal manifestations. Clinicians should have a high index of suspicion for EG when faced with gastrointestinal symptoms and peripheral eosinophilia to avoid incorrect diagnosis and inappropriate treatments. A 24-year-old woman was admitted to our hospital complaining of acute right lower quadrant abdominal pain and a laparoscopic appendectomy performed for a presumed diagnosis of an acute appendicitis. However, the procedure revealed bowel edema and a moderate amount of ascites without evidence of a suppurative appendicitis. Postoperatively, she showed persistent and progressive eosinophilia, exudative eosinophilic ascites, eosinophilic infiltration of the resected appendix wall, and eosinophilic infiltration of gastroduodenal mucosa. A punch biopsy of the abdominal skin also revealed inflammation with marked eosinophilic infiltration of the skin. She recovered after the treatment with a low dose of steroid for the EG with eosinophilic dermatitis. EG with eosinophilic dermatitis has not been reported yet and is considered fortuitous in this case.     

Eosinophilic disorders

Eosinophilic inflammatory responses occur in association with multiple disorders. Although the initial cause and the affected organs vary among the different eosinophilic disorders, there are only 2 major pathways that mediate eosinophilia: (1) cytokine-mediated increased differentiation and survival of eosinophils (extrinsic eosinophilic disorders), and (2) mutation-mediated clonal expansion of eosinophils (intrinsic eosinophilic disorders). Independent from the original trigger, the most common cause of eosinophilia is the increased generation of IL-5-producing T cells. In some cases, tumor cells are the source of eosinophil hematopoietins. The intrinsic eosinophilic disorders are characterized by mutations in pluripotent or multipotent hematopoietic stem cells leading to chronic myeloid leukemias with eosinophils as part of the clone. Here, we propose a new classification of eosinophilic disorders on the basis of these obvious pathogenic differences between the 2 groups of patients. We then discuss many known eosinophilic disorders, which can be further subdivided by differences in T-cell activation mechanisms, origin of the cytokine-producing tumor cell, or potency of the mutated stem cell. Interestingly, many subgroups of patients originally thought to have the idiopathic hypereosinophilic syndrome can be integrated in this classification.     

Eosinophilic gastroenteritis

Eosinophilic gastroenteritis is an uncommon condition affecting one or more segments of the gastrointestinal tract, mainly the stomach and small bowell, the principal changes being a variable degree of both oedema and eosinophilic infiltration. Occurring at any age it is commonest in the third decade, is often associated with abdominal pain and peripheral blood eosinophilia, and responds to steroids: allergy or asthma occurs in some 25% of patients. The oedema and eosinophilia involve the submucosa generally but any layer of the gut may be affected. The aetiology is discussed: no allergic or other cause has been determined and it is probable that further knowledge of the role of the eosinophil may be necessary before the precise nature of the lesion can be understood. An association of eosinophilic gastroenteritis with malabsorptive or protein-losing enteropathies is noted.     

Eosinophilic esophagitis

ObjectiveTo review the understanding of the pathogenesis of eosinophilic esophagitis (EoE) and the role of the immune system in the disease process.Data SourcesPeer-reviewed articles on EoE from PubMed searching for “Eosinophilic Esophagitis and fibrosis” in the period of 1995 to 2013.Study SelectionsStudies on the clinical and immunologic features, pathogenesis, and management of EoE.ResultsRecent work has revealed that thymic stromal lymphopoietin and basophil have an increased role in the pathogenesis of disease. Additional understanding on the role of fibrosis in EoE is emerging.ConclusionThe incidence of EoE is increasing like most atopic disease. Similar to other allergic diseases, EoE is treated with topical steroids and/or allergen avoidance.     

Eosinophilic pneumonias

Eosinophilic pneumonias (EP) encompass a wide spectrum of lung diseases characterized by peripheral blood eosinophilia (>1 x 10(9) eosinophils/l) and/or alveolar eosinophilia (>25%). Blood eosinophilia may be lacking, as in the early phase of idiopathic acute EP, or in patients already taking oral corticosteroids. EP may present with varying severity, ranging from almost asymptomatic infiltrates to the acute respiratory distress syndrome necessitating mechanical ventilation. Possible causes of EP must be thoroughly investigated, especially drugs and the variety of parasitic infections (considering history of travel or residence in areas of endemic parasitic infection). However, chronic EP remains idiopathic in many cases. When present, extrathoracic manifestations lead to suspect Churg-Strauss syndrome (CSS) or the hypereosinophilic syndrome (HES), the prognosis of which is dominated by cardiac involvement. Apart from the treatment of specific causes when possible, corticosteroids remain the cornerstone of symptomatic treatment for eosinophilic disorders, usually with a dramatic response, but frequent relapses when tapering or after stopping the treatment. The adjunction of immunosuppressants to corticosteroids is necessary in patients with CSS and poor prognosis factors. Imatinib has recently proven effective in the treatment of the myeloproliferative variant of the HES.     

Non-allergic Eosinophilic Inflammation

Much is known about the eosinophilic processes associated with antigens, tumors, and infection, yet data on other causes of eosinophilic inflammation are scarce. This paper investigates the locations and causes of other nonrespiratory eosinophilic inflammation. Although eosinophilic inflammation can involve locomotor, urinary, cardiovascular, nervous, gastrointestinal, and other mucosal surfaces, such inflammation also can accompany tissue trauma, foreign-body reactions, and necrotic or granulomatous processes. Despite their cytolytic/histolytic effects, eosinophil leukocytes are a component of tissue remodeling, can be antigen-presenting cells, and have a role in the reproductive system and in blood coagulation. The study of various types of eosinophilic inflammation may increase our understanding of the biological responses of eosinophil leukocytes to different inflammatory stimuli.     

Eosinophilic pustular folliculitis

Classical eosinophilic pustular folliculitis, or Ofuji's disease, is a chronic and relapsing dermatosis that is predominantly reported in East Asian populations. Clinically, the disease typically begins as small papules, which enlarge and coalesce into a large plaque, usually on the face. The histopathology is characterized by a prominent eosinophilic infiltrate in the dermis with concentration around pilosebaceous units, often with eosinophilic microabscess formation. The differentiation of eosinophilic pustular folliculitis from other eosinophilic dermatoses is practically challenging and requires close clinicopathologic correlation. Eosinophilic pustular folliculitis may also be associated with human immunodeficiency virus infection, various drugs, and some lymphomas and could also be thought of as a nonspecific dermatopathologic pattern in such settings. The cause of classical eosinophilic pustular folliculitis is unknown, although immune processes are almost certain to play a key role in its pathogenesis.