The main objective of this study is to determine the frequency of different gastrointestinal disorders as the cause of diarrhea in patients at a tertiary referral center using confocal laser endomicroscopy.

Background:

Diarrhea is characterized by frequent, loose, and watery bowel movements. Common causes include various gastrointestinal infections (e.g. clostridium difficile, salmonella), inflammatory bowel disease (ulcerative colitis, Crohn´s disease), drugs (e.g. antibiotics) and malabsorption syndromes (e.g. celiac and Whipple's disease). Confocal laser endomicroscopy (CLE) is rapidly emerging as a valuable tool for gastrointestinal endoscopic imaging, enabling the endoscopist to obtain an "optical biopsy" of the gastrointestinal mucosa during the endoscopic procedure.

Scope:

In patients with diarrhea.

Methods:

Patients were randomized in two groups. Group 1: Patients underwent standard video colonoscopy for the evaluation of their symptoms. Group 2: During the endoscopic procedure CLE will be performed additionally.

Procedure:

The patient underwent colonoscopy. In Group 2 patients´ will receive intravenous fluorescein or topical mucosal staining with acriflavin or cresyl violet during the procedure, followed by in-vivo CLE of the tissue. Confocal images are digitally saved and analyzed afterwards.

Inclusion Criteria:

• Written informed consent
• Age 18-85 years
• Ability of subjects to understand character and individual consequences of clinical trial
• Subjects undergoing colonoscopy

Exclusion Criteria:

• Inability to provide written informed consent
• Severe Coagulopathy (Prothrombin time < 50% of control, Partial thromboplastin time > 50 s)
• Impaired renal function (Creatinine > 1.2 mg/dl)
• Pregnancy or breast feeding
• Active gastrointestinal bleeding
• Known allergy to fluorescein, acriflavin or cresyl violet
• Residing in institutions (e.g. prison)

Patients of a tertiary referral hospital.