Rosacea. Artwork of patients' faces with the skin rash and pustules of the chronic skin disease known as rosacea or acne rosacea. In the centre is a cross-section of a pustule developing in a hair follicle in the skin. The follicle is blocked and a build-up of pus and skin oils (yellow) forms the bulge of the pustule. Skin cells (pink) and blood vessels (red and blue) are also seen. The cause of the disorder is unknown but it can be precipitated by overuse of corticosteroid creams. Treatment involves the antibiotic drug tetracycline, though it does not cure the disorder. Rosacea tends to recur for up to 10 years and then disappears.