Doctor's Notes on Sty (Stye)
A sty (or stye) is a localized infection causing inflammation of the edge of the eyelid, typically involving the eyelash hair follicles or eyelid glands (Meibomian glands). The medical term for sty is hordeolum. Infection with the bacterium Staphylococcus aureus (S. aureus) is the most common cause of a sty.
A sty produces characteristic signs and symptoms. There is usually a bump or lump on the eyelid margin. The bump resembles a pimple or boil. Associated symptoms can include eyelid swelling, pain in the eyelids, redness of the overlying skin, swelling of the eyelid, and increased tear production. There may also be a sense of having a foreign body in the eye. A sty can be located on the exterior (facing outward) or interior surface of the eyelid.
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.