Candidiasis of the oesophagus, pill camera view. This is an infection by the yeast Candida albicans, a single-celled fungus that forms a normal part of the intestinal flora. Its population is usually kept in check by the immune system and by competition from other organisms in the flora, such as bacteria. If this balance is disturbed, for instance by a course of antibiotics or immunosuppression due to AIDS or other causes, the yeast population can grow rapidly. Treatment is with anti-fungal drugs. A pill camera is a pill-sized camera swallowed to image the digestive tract.