The cause of localised anal dampness is mainly due to the flow of secretions from the anal canal out of the anus. Therefore, if there is residual faecal matter in the anal canal or if there is a high level of inflammatory irritation, there is a risk of the discharge turning yellow. If the patient has a loose anal canal, a small amount of faeces may also pass out of the anal canal, thus increasing the local dampness and itching around the anus.