Bump on the eyelid; Stye
In addition to the red, swollen bump, other possible symptoms include:
A doctor can diagnose a stye just by looking at it. Special tests are usually not necessary.
Pasternak A, Irish B. Opthalmologic infections in primary care. Clin Fam Pract. 2004; 6(1):19.
Noble J. Textbook of Primary Care Medicine. 3rd ed. St. Louis, Mo: Mosby; 2001.