Concentration of water-soluble ingredients on the surface of a waterbased paint, typically on a ceiling surface in rooms that have high humidity (e.g. bathrooms, kitchens and laundries); may be evident as tan or brown spots or areas, and can sometimes be glossy, soapy or sticky.
Wash the affected area with soap and water and rinse. Problem may occur once or twice before leechable material is completely removed. When paint is applied in a bathroom, it is helpful to have it dry thoroughly before using the shower. Remove all staining before repainting.
Source: The Paint Quality Institute