This is a first report of three patients with silicone feeding tubes (two with percutaneous endoscopic gastrostomies and one with a jejunostomy, all 20 French catheters) that have formed a thick yeast crust on the inner luminal surface causing tube occlusion in two cases. Candida species were isolated in all three tubes. The yeast crust could not be removed with a brush or with fungicidal drugs such as nystatin and amphotericin B. Histologic sections through these feeding tubes revealed yeast penetration through the silicone material, explaining the adherent nature of the crust. This complication may also explain the observed material deterioration with subsequent breakage.