Conjunctivitis
👁️ Conjunctivitis (inflammation of the conjunctiva) is one of the most common causes of red eye.
⏳ Most cases are benign and self-limiting (7–10 days), but persistence, pain, or visual loss warrant urgent referral.
🦠 Infective conjunctivitis is usually viral and does not routinely require antibiotics.
⚠️ Always ask about contact lens use — risk of Pseudomonas keratitis.
📖 About
- The conjunctiva = thin mucous membrane lining the eyelids + sclera.
- Highly vascular → easily inflamed, causing redness, discharge, irritation.
- Spread via fingers, towels, or respiratory droplets → good hygiene essential.
🧾 Aetiology
- 🦠 Viral: Adenovirus (most common), enterovirus, HSV.
- 🧫 Bacterial: Strep pneumoniae, Staph aureus, H. influenzae, Moraxella.
Hyperacute = gonococcal (sight-threatening!).
- 🤧 Allergic: Hay fever, atopy, seasonal allergens. Drug-induced (e.g., chloramphenicol).
- 🌍 Chronic: Trachoma (Chlamydia trachomatis) → scarring, blindness in endemic regions.
- ⚠️ Other: Autoimmune (Stevens–Johnson, cicatricial pemphigoid).
🔎 Clinical Features
- ⏱️ Resolves spontaneously in 7–10 days (if simple infective).
- 👁️ Red/pink eye with gritty sensation.
- Bacterial: Mucopurulent discharge, “glued” eyelids on waking.
- Viral: Watery discharge, often following URTI; highly contagious.
- Allergic: Bilateral, intense itching, stringy discharge, seasonal recurrence.
- STI-related: Gonococcal → copious purulent discharge, rapid corneal ulceration. Chlamydial → chronic, follicles, preauricular lymphadenopathy.
🧪 Investigations
- Usually clinical diagnosis.
- Swabs/culture if: atypical, recurrent, severe, or non-resolving.
- NAATs if chlamydia/gonorrhoea suspected.
- Slit-lamp exam if keratitis, uveitis, or foreign body suspected.
💊 Management
- General Measures (all types):
🧼 Hand hygiene, avoid sharing towels, no contact lenses until resolved.
- Allergic conjunctivitis:
❄️ Cool compresses, lubricants, topical antihistamines (olopatadine, azelastine).
Mast cell stabilisers (sodium cromoglicate) for recurrent cases.
- Infective conjunctivitis:
💧 Lubricants for comfort.
Most adults = viral → no antibiotics.
Children with mucopurulent discharge may receive chloramphenicol if severe.
- Bacterial (purulent):
Chloramphenicol 0.5% drops q2h × 48h → then QDS until 48h after resolution.
Alternative: Fusidic acid gel BD (esp. children or compliance issues).
- STI-related:
🚨 Ophthalmia neonatorum (gonococcal) → emergency admission.
IV/IM ceftriaxone + topical therapy.
Chlamydial → systemic azithromycin/doxycycline + sexual health referral.
🚩 Red Flags — Refer Ophthalmology Urgently
- 👓 Contact lens wearers (risk of pseudomonal keratitis).
- 🩸 Pain, photophobia, or ↓ vision (uveitis, keratitis).
- ⚠️ Copious purulent discharge (gonococcal).
- 🧪 Suspected STI-related conjunctivitis.
- Recurrent or persistent >10 days despite treatment.
📚 References
