Conjunctivitis


Conjunctivitis is an acute inflammation of the conjunctiva due to a bacterial or viral infection, allergy, or irritation.
Conjunctivitis may be associated with measles or rhinopharyngitis in children.
In the absence of hygiene and effective treatment, secondary bacterial infections may develop, affecting the cornea (keratitis).

Clinical features

– Clinical signs of all conjuctivites include: redness of the eye and irritation. Visual acuity is not affected.

– Depending on the cause:
• abundant and purulent secretions, eyelids stuck together on waking, unilateral infection at onset: bacterial conjunctivitis;
• watery (serous) secretions, no itching: viral conjunctivitis;
• excessive lacrimation, eyelid oedema, intense itching: allergic conjunctivitis.

– In endemic areas, turn both upper eyelids up to check for signs of trachoma (see Trachoma).

– Suspect keratitis if patient reports intense pain (more than is usually associated with conjunctivitis) and photophobia. Instill one drop of 0.5% fluorescein to check for possible ulcerations.

– Always check for foreign bodies (subconjunctival or corneal) and remove after administering 0.4% oxybuprocaine anaesthetic eye drops. Never give bottle of eye drops to the patient.

Treatment

Bacterial conjunctivitis
– Clean eyes 4 times daily with boiled water or 0.9% sodium chloride.
– Apply into both eyes 1% tetracycline eye ointment: one application 2 times daily for 7 days
– Never use corticosteroid drops or ointment.

Viral conjunctivitis
– Clean eyes 4 times daily with boiled water or 0.9% sodium chloride.
– Apply local antibiotics if there is a (risk of) secondary bacterial infection (see above).

Allergic conjunctivitis
– Local treatment as for viral conjunctivitis.
– Antihistamines PO for one to 3 days (see Urticaria, Chapter 4).

Note: in the event of a foreign body, check tetanus immunisation status.