A 32-year-old man wakes with both eyes glued shut by thick yellow discharge for two days. The eyes are red and gritty but not itchy and not particularly painful. His vision is normal. It started in one eye and spread to the other. He has no cold symptoms.
Examination Findings
Visual acuity: 6/6 both eyes. Both eyes: marked injection, thick yellow-green purulent discharge, lids crusted shut on waking. Slit lamp: papillary reaction of the tarsal conjunctiva, intact cornea with no infiltrate, no follicles. No preauricular lymph node. Started in the right eye two days ago, the left joined yesterday.
Investigations
The diagnosis is clinical: purulent discharge with papillae and no viral features. Fluorescein staining excludes corneal involvement. Cultures are reserved for severe, recurrent or non-resolving cases, neonates, or suspected gonococcal disease — not needed for this classic mild adult case.
Questions to Think About
- What single feature most strongly points to bacterial rather than viral cause?
- What does the papillary (rather than follicular) reaction signify?
- Why is he told to stop wearing his contact lenses?
Diagnosis
Acute bacterial conjunctivitis: bilateral purulent conjunctivitis with stuck-together lids on waking, papillary reaction and no preauricular node.
Reasoning
Reasoning: Acute bilateral thick purulent discharge with lids stuck shut, papillary conjunctival reaction, no itch, no follicles and no preauricular node is acute bacterial conjunctivitis. The purulence excludes viral (watery) and allergic (itchy) causes. Diagnosis: acute bacterial conjunctivitis, bilateral. Management: typical management includes topical antibiotics per local protocol, lid hygiene, hand/towel precautions, and pausing contact lens wear. He is told it spreads by hands, that treatment shortens it, and which symptoms demand re-examination.
Differential Diagnosis
- Adenoviral conjunctivitis — ruled out: the discharge is thick and purulent (not watery), lids stick shut, and there are no follicles or preauricular node and no recent cold.
- Allergic conjunctivitis — ruled out: no itching at all; the dominant feature is purulent discharge, not itch.
- Chlamydial conjunctivitis — ruled out: acute onset over two days with frank pus, no chronic follicular course.
Management
Typical management includes topical antibiotic drops or ointment per local protocol, with advice on lid cleaning to remove the crusts and strict hand and towel hygiene to protect the household. Contact lens wear is paused. He is told it is contagious through hands and towels, that the drops shorten the illness, and to return if vision blurs or pain develops (corneal involvement).
Key Learning Points
- Pus means bacterial until proven otherwise: thick yellow-green discharge with stuck lids is the bacterial signature.
- Papillae point to bacterial/allergic; FOLLICLES point to viral/chlamydial — the tarsal reaction tells the cause.
- No itch argues against allergy; no watery discharge or node argues against virus.
- Most acute bacterial conjunctivitis is self-limited, but topical antibiotics shorten the course and reduce spread.
- Hygiene is treatment: handwashing, separate towels, no eye rubbing — the infection spreads by hands.
Red Flags
- Vision blur or significant pain with purulent conjunctivitis — examine the cornea; a bacterial ulcer may be starting.
- Copious hyperacute pus within hours — consider gonococcal disease, which is an emergency.
- No improvement after a few days of treatment — re-examine and consider culture.
Educational content only — not medical advice. Clinical decisions must be made by a qualified professional for the individual patient.