Clinical Features/Diagnostics

• Typically nonspecific presentation; common clinical features include: [3]

  • Burning or foreign body sensation

  • Itching (most intense in seasonal allergic conjunctivitis)

  • Conjunctival injection: conjunctival hyperemia with dilatation of blood vessels → ocular hyperemia and red eye

  • Chemosis: edema of the conjunctiva due to conjunctival vein vasodilatation and increased blood flow

  • Discharge and crust formation

  • Photophobia

• Additional features may be present depending on etiology, including:

  • Conjunctival follicle: seen in viral or chlamydial conjunctivitis

    • A small, raised lymphoid follicle with a yellowish-white appearance due to hyperplastic tissue

    • Vascularization is usually peripheral.

    • Located in the palpebral or bulbar conjunctiva

  • Preauricular lymphadenopathy: seen in viral or gonococcal conjunctivitis

  • Concomitant corneal inflammation (keratoconjunctivitis): seen in viral and nonallergic conjunctivitis

Conjunctivitis is the most common cause of red eye and is usually a clinical diagnosis

Conjunctivitis is usually a clinical diagnosis. Consider diagnostic studies if there is diagnostic uncertainty or suspicion for a serious infection.

• Obtain a full medical history including comorbidities, medications, and history of eye conditions.

• Perform eye examination, including:

  • Visual acuity

  • Slit-lamp examination