Conjunctivitis

Question 1

Definition

Answer 1

Inflammation of the conjunctiva, which can be infectious or non-infectious

Question 2

Bacterial causes

Answer 2

• Staph Aureus
• Haemophillus influenzae
• Strep pneumoniae
• Chlamydia and Neisseia Gonnorrheoa (rare but potentially sight-threatening

Question 3

Viral causes (MC infectious cause)

Answer 3

• Adenovirus
• Coxsackie
• Enterovirus
• Herpes Simplex: rare but potentially sight-threatening

Question 4

Non infectious causes

Answer 4

Allergic conjunctivitis (MC cause overall)

Question 5

Epidemiology and Risk factors

Answer 5

• Exposure to allergen e.g. pollen, dust mites, perfume
• History of atopy
• Close contact with a person with viral or bacterial conjunctivitis
• Contact lens wearers: especially soft, extended-lens wearers

Question 6

Signs

Answer 6

• Conjunctival follicles: MC in viral
• Superficial punctate keratopathy: MC in viral
• Preauricular lymph nodes: tender and may be present in viral

Question 7

Symptoms

Answer 7

• Itchiness in one or both eyes: MC allergy conj
• Conjunctival injection (redness)
• Gritty sesnation: in one or both eyes
• Discharge:
  = purulent: bactieral
  = watery: viral and allergic
• Difficulty opening eyes in the morning: usually bacterial due to crusting
• Tearing

Question 8

Bacterial conjunctivitis classic features

Answer 8

Purulent discharge = eyes stuck together in the morning

Question 9

Viral conjunctivitis classic features

Answer 9

• Recent UTI,
• Watery discharge
• Perauricular lymph nodes

Question 10

Diagnosis

Answer 10

Clinical diagnosis
- Swabs not routinely taken unless the patient fails to respond to initial therapy

Question 11

Treatment

Answer 11

FIRST LINE =
- Watch and watch, resolve without intervention within 7 days
- Practice good hygiene, avoid touching eyes with hands, wash hands regularly, use clean towels and do not share towels, do not wear lenses
- No exclusion period from school
- Artificial tears: over the counter drops relieve symptoms
- Mast cell stabilisers e.g sodium cromoglycate

Question 12

Second line treatment

Answer 12

Topical Abx:
- Chloramphenicol 0.5% eye drops: 2 hourly for 2 days, then QDS for 5 days
- Chloramphenicol 1% oitment: QDS for 2 days then BD for 5 days
- Fusidic acid 1% eye drops: second line particularly in pregnancy, BD for 7 days

Question 13

Complications

Answer 13

• Keratitis: rarely, bacterial conjunctivitis can spread to the cornea.
  DDx: Herpes can also cause keratitis and corneal scarring
• Subepithelial corneal infiltrates
• Dry eyes