[Drug-induced enterocolitis]. / Entérocolites médicamenteuses.

Drug-induced enterocolitis is a frequent but underdiagnosed disease. Gross and microscopic features are often non-specific, except for particular cases. Drug-induced enterocolitis is usually a diagnosis of exclusion. In this article we describe the pathologic features and causes of various cases of drug-induced enterocolitis.

[Microscopic colitis: collagenous colitis and lymphocytic colitis]. / Les colites microscopiques : colite collagène et colite lymphocytaire.

Microscopic colitis is currently classified as a chronic inflammatory bowel disorder and encompasses two entities: lymphocytic colitis and collagenous colitis. Patients with microscopic colitis present with a well-tolerated chronic watery diarrhea, sometimes with abdominal pain. Colonoscopy is normal. Diagnosis of microscopic colitis is established by histologic examination of colonic biopsies, showing a thickened subsurface collagen band higher than 10 microm in collagenous colitis, and an increased number of surface intra-epithelial lymphocytes higher than 20 lymphocytes per 100 epithelial cells in lymphocytic colitis. Causes of microscopic colitis are still unknown, although a drug-induced etiology is found in some cases. Patients are usually treated with budesonide but recurrences are frequent.

[Anal and anal margin tumors]. / Pathologie tumorale anale et péri-anale.

Tumors of the anal canal and anal margin are rare. They may raise specific problems for the pathologist. Benign tumors mainly consist of condylomas, cloacogenic polyps and fibro-epithelial polyps. Cancers are infrequent and consisted of well-differentiated squamous cell carcinoma, or poorly differentiated basaloid squamous cell carcinoma. The other malignant tumors are very rare.