[Lymphocytic " itis", from esophagus to large bowel]. / « ites ¼ lymphocytaires, de l'œsophage au côlon.

Intra-epithelial lymphocytosis is an elementary lesion frequently observed in the gastrointestinal tract, which can be found from the esophagus to the colon. Many conditions of a varied nature (dysimmunitary diseases, drugs, infections…) are associated with intra-epithelial lymphocytosis, and the etiological diagnosis most often requires an anatomo-clinical correlation. The pathologist will have to identify histological lesions associated with intra-epithelial lymphocytosis allowing the diagnosis to be oriented in order to propose appropriate treatment. In this review, the main entities associated with digestive intra-epithelial lymphocytosis will be presented, detailing the key elements allowing their diagnosis.

Les colites microscopiques.

Microscopic colitis is frequently found as a cause of chronic watery diarrhea in women after menopause. The disease can be associated with a medication side effect in half of the patients (non-steroidal anti-inflammatory drugs or proton pump inhibitors for instance). Colonic biopsies are mandatory for the diagnosis of microscopic colitis and should be performed in several locations of the colon. Management of microscopic colitis is first based on avoiding iatrogenic factors and smoking together with symptomatic treatment of diarrhea (loperamide, cholestyramine). In case of failure or severe symptoms, budesonide is the key treatment. The aim of the treatment is to achieve clinical remission, defined as less than 3 liquid stools per day, to improve quality of life. After a first course of budesonide, recurrence of diarrhea is frequent and a maintenance therapy can be prescribed for several months. In case of intolerance or refractoriness, second-line therapy (immunosuppressants, biological therapy, surgery) should be discussed in multidisciplinary team meeting.

[Microscopic Colitis]. / Mikroskopische Kolitis.

Microscopic colitis (MC) is still an underestimated cause of chronic, non-bloody watery diarrhea. It is typically manifested in elderly patients with a female predominance. The incidence of microscopic colitis has been increasing. The aetiology and pathophysiology remain unclear. Conditions associated with it include autoimmune diseases. There may be a genetic predisposition, as familial cases have been described. As implicated by the name microscopic colitis, the diagnosis is found by histological examination. There are mainly two subtypes, the lymphocytic colitis (LC) and the collagenous colitis (CC). Even if the condition's long-term course is benign, a chronic recurrent course of the symptoms is frequent. Due to the symptoms, there is an impairment of patient's health-related quality of life. A correct diagnosis and therapy is therefore mandatory. The aim of this paper is to create awareness for microscopic colitis.