Allergic conjunctivitis

Background

• Conjunctivitis due to exposure to an allergen
• Chronic allergic conjunctivitis is also called vernal conjunctivitis

Clinical Features

Bilateral allergic contact dermatitis caused by eyedrops (left) and after resolution (right).

Seasonal allergic conjunctivitis. Inverted eyelid showing mild conjunctival injection and moderate chemosis.

Acute allergic conjunctivitis.

Chronic allergic conjunctivitis.

Contact allergic blepharoconjunctivitis (from eyedrops).

• Itching
• Watery discharge
• Injected and edematous conjunctiva
• Papillae on inferior conjunctival fornix
• Red, swollen eyelids

Differential Diagnosis

Conjunctivitis Types

• Viral conjunctivitis
  • Epidemic keratoconjunctivitis
  • Herpes zoster ophthalmicus
  • Herpes simplex keratitis
• Bacterial conjunctivitis
  • Gonorrheal conjunctivitis
  • Chlamydia conjunctivitis
• Allergic conjunctivitis
• Caustic keratoconjunctivitis

Evaluation

Clinical diagnosis of conjunctivitis

Conjunctivitis

	Bacterial	Viral	Allergic
Bilateral	50%	25%	Mostly
Discharge	Mucopurulent	Clear, Watery	Cobblestoning, none
Redness	Yes	Yes	Yes
Pruritis	Rarely	Rarely	Yes
Additional	Treatment: Antibiotics	Treatment: Hygiene	Seasonal

Management

• Mild: avoid triggers, cool compresses for 15 minutes QID
• Moderate: Histamine-blocking drops (e.g. naphazoline/pheniramine 0.025%/0.3%, olopatadine, pemirolast, or ketotifen)
• Severe: refer to ophthalmology for possible steroid therapy

Disposition

• Discharge with ophthalmology follow-up

See Also

• Conjunctivitis
• Eye Algorithms (Main)