What do we know today about drug-induced microscopic colitis? A case of lymphocytic colitis on olmesartan.

Microscopic colitis is part of the differential diagnosis of chronic watery diarrhea. Colonoscopy discloses a normal looking mucosa, therefore its diagnosis is based on histology of colonic biopsies. Two main phenotypes are distinguished: collagenous colitis and lymphocytic colitis. A third entity, incomplete microscopic colitis or unspecified microscopic colitis has been reported in the literature. It affects preferentially women over 60 years of age and its association with certain drugs is increasingly established. In case of suspected drug-induced microscopic colitis, identification of the responsible drug is a key to management. After discontinuation of the suspected drug, the gold standard of treatment is budesonide both for induction and for maintenance in case of clinical relapse, as is often the case after discontinuation. Therapy with immunomodulators, biologics, or surgery is reserved for refractory forms of microscopic colitis after multidisciplinary consultation. Through the clinical case of colitis on olmesartan, we will review the latest recommendations on drug-induced microscopic colitis.

An unusual recurrent ileocolonic injury.

Potassium binders (Kayexalate® and Sorbisterit®) are commonly used to treat hyperkaliemia. They are made of sodium or calcium polystyrene sulfonate. Their use is associated with multiple adverse effects including ileocolonic (or more rarely upper digestive tract) injuries which can lead to necrosis or perforations. This side effect is mostly seen in patients with chronic kidney disease or constipation. It presents with abdominal pain, diarrhea or hematochezia. The diagnosis is made when the histo-logical analysis of samples from the erythematous or ulcerated digestive wall finds polystyrene sulfonate crystals embedded in the mucosa. This diagnosis can be suspected by taking a careful initial drug inventory, if the clinician is aware of this rare but serious adverse effect. The lack of specificity of clinical symptoms and endoscopic lesions makes this inventory even more essential. Treatment is mainly supportive and requires cessation of the drug, while surgery is inevitable in the most severe cases.

[Bourneville tuberous sclerosis and colonic polyposis]. / Sclérose tubéreuse de Bourneville et polypose colique.

Tuberous sclerosis is an autosomal dominant genetic disorder that is characterized by epilepsy, mental retardation and facial angiofibromas. Usually, the disease is diagnosed in childhood but there are frustrates form of tuberous sclerosis with or without genetic mutation. This clinical case about a man who is diagnosed a colonic polyposis, a rectal adenocarcinoma and a tuberous sclerosis.

La sclérose tubéreuse de Bourneville (STB) est une maladie génétique autosomique dominante qui se manifeste principalement par la triade épilepsie, retard mental et angiofibromes faciaux. Généralement, elle est diagnostiquée dans l'enfance, mais il existe des formes cliniques frustres avec ou sans mutations génétiques. La recherche d'autres manifestations cliniques peut aider au diagnostic notamment l'atteinte intestinale. Notre cas clinique rapporte la découverte d'une polypose intestinale et d'un cancer du rectum chez un patient méconnu de sa maladie génétique. L'intérêt est de voir, à partir de la littérature, la fréquence de la polypose colique ainsi que du cancer colorectal dans la STB et de se poser la question d'un dépistage systématique dans cette population.