Conjunctivitis

Question 1

Definition

Answer 1

Inflammation of the conjunctiva.

o Associated inflammation of the cornea –> keratoconjunctivitis
o Associated eye lid involvement –> blepharoconjunctivitis

Question 2

Aetiology

Answer 2

• Infectious
o Viral
o Bacterial

• Non-Infectious
o Allergic
o Mechanical/irritative/toxic
o Immune-mediated
o Neoplastic

• NOTE: use of contact lenses is a risk factor for conjunctivitis

Question 3

Epidemiology

Answer 3

• WORLDWIDE distribution
• Affects any age group
• No gender, ethnic or social preponderance

Question 4

Presenting symptoms

Answer 4

• Red eye (usually generalised and often bilateral)
• Irritation, discomfort and grittiness
• Discharge (may be watery, mucoid, sticky or purulent depending on cause)
• Photophobia (suggest corneal involvement)
• Visual acuity usually unaltered

Question 5

Signs on physical examination

Answer 5

• Conjunctival injection (i.e. blood shot eyes)
• Dilated conjunctival vessels
• Conjunctival chemosis (swell of the conjunctiva)
• Conjunctival follicles (round collections of lymphocytes appearing as small domeshaped nodules)
• Conjunctival papillae (associated with allergic immune response)

Question 6

Investigations

Answer 6

• Diagnosis is usually made following history and examination
• Further investigations are performed by specialists