Biliary obstruction and cholangitis are common problems in gastroenterology and need specific therapeutic interventions. Besides a variety of potential causes, infections of the biliary tract with Candida and other fungal species have increasingly been reported in the last few years [1-6]. Fungal infections can even lead to common bile duct (CBD) obstruction, as previously reported [7]. Because of the difficulty of gaining bile samples, little is known about the microbial flora of the bile. In a first prospective, observational study, 123 consecutive patients undergoing ERCP for various indications were screened for fungal species [8]. According to this data Candida species may be very frequently be detected in the bile (54/123 patients, 44 % of the cases). As significant risk factors immunosuppression and long-term antibiotic therapy were identified. The main issue in this context is whether positive diagnostic findings represent fungal infection or fungal colonization. Especially interesting is the question, if patients with positive fungal cultures of bile samples should be treated or not and under which circumstances.