Eye exam
Fluorescein stain of cornea (especially in infants) to assess for corneal lesion
Culture: if severe
Bacterial conjunctivitis
Viral conjunctivitis
Epidemic keratoconjunctivitis
Allergic conjunctivitis
Herpes zoster ophthalmicus
Chlamydia conjunctivitis
Herpes simplex keratitis
Caustic keratoconjunctivitis