Conjunctivitis is inflammation of the conjunctiva. The conjunctiva is a thin layer of tissue that covers to inside of the eyelids and the sclera of the eye.

Aetiology: There are a range of causes of acute conjunctivitis, including allergy, bacterial or viral infection, mechanical stress, and irritation by toxic chemicals or medication.

Risk factors:

• Exposure to infected person (very contagious)
• Infection in the other eye (can spread)
• Environmental irritants
• Allergen exposure - Grass, trees, pollen, cats, dogs
• Asian or mediterranean
• Young male
• Trauma - mechanical, chemical, ultraviolet
• Hot,dry evironment
• Prior infection with HSV
• More prevalent in people with hay fever, allergies

PC

*presence of risk factors

• Red eye (bloodshot)
• Itching - more common in allergic (seasonal allergic conjunctivitis)
• Discharge -
  • Purulent - More common in bacterial
  • Serous - More common in viral
  • Mucoid - More common in allergic