[Diverticular disease - diagnosis and classification]

A reliable diagnosis is fundamental for operative, interventional and conservative treatment of the different facets of diverticular disease. Not only differential diagnoses but also overlap or coincidence with other entities sharing similar symptoms must be considered. Furthermore, an adequate surgical strategy and correct stratification of complications is mandatory. Subsequently, in the light of currently validated diagnostic techniques, the consensus conference of the German Societies of Gastroenterology (DGVS) and Visceral Surgery (DGAV) has released a new classification of diverticulitis displaying the different facets of diverticular disease. This classification also comprises symptomatic uncomplicated diverticular disease (SUDD), largely resembling irritable bowel syndrome, as well as diverticular bleeding. While detailed history, physical examination and laboratory testing are of great importance for exploring a patient with diverticular disease, they are not sufficient to diagnose (or stratify) diverticulitis without cross-sectional imaging using ultrasonography (US) or computed tomography (CT). The diagnostic value of qualified US is equipotent to qualified CT, complies with relevant legislation for radiation exposure protection and is frequently effective for diagnosis. Therefore, US is considered to be the first choice for imaging in diverticular disease. In contrast, CT has definite indications in unclear, discrepant situations or insufficient US performance. Strengths and weaknesses of both methods are discussed. Endoscopy is not required for the diagnosis of diverticulitis and should not be performed in an acute attack. Colonoscopy, however, is warranted after healing of diverticulitis, prior to elective surgery and in cases of an atypical course. Prior exclusion of perforation is considered mandatory. An unequivocal indication for colonoscopy is diverticular bleeding and the rapid performance (within 12-24 h) allows better identification of sites of bleeding and endoscopic interventions.