Ophthalmia neonatorum (neonatal conjunctivitis)
Definition and key principles
Ophthalmia neonatorum is conjunctival inflammation occurring in the first 4 weeks of life. Causes include bacterial (notably Neisseria gonorrhoeae, Chlamydia trachomatis, staphylococci), viral (herpes simplex virus) and chemical irritation.
Some causes (gonococcal infection, HSV) can progress rapidly and threaten vision or indicate systemic infection; early recognition, appropriate specimen collection and rapid escalation are essential.
When neonatal bacterial infection is suspected, follow the principles of prompt inpatient assessment and early systemic therapy (NICE NG195).
Epidemiology and aetiology
Most cases are acquired during passage through an infected birth canal. Typical organisms and helpful diagnostic clues:
- Neisseria gonorrhoeae: onset usually ≤5 days; very rapid onset with marked conjunctival hyperaemia, tense eyelid oedema, chemosis and copious purulent discharge; corneal ulceration can occur early - ophthalmic emergency.
- Chlamydia trachomatis: onset 5-14 days; eyelid oedema, conjunctival injection and serous/mucoid or serosanguinous discharge; may form pseudomembranes; less fulminant than gonococcus but requires systemic therapy.
- Herpes simplex virus (usually HSV‑2): onset typically 7-14 days (variable); conjunctivitis ± keratitis, often with vesicular skin/oral lesions or systemic signs - risk of disseminated disease.
- Staphylococcal and other skin flora: usually milder conjunctivitis with purulent discharge appearing around the end of week 1.
- Chemical conjunctivitis: mild irritation within 24-48 hours after topical prophylaxis (historical silver nitrate).