Inflammation of the conjunctiva

Causes/Factors

  • Bacterial Infection: Caused by bacteria such as Staphylococcus or Streptococcus.
  • Viral Infection: Viruses, including adenoviruses, often lead to infectious conjunctivitis.
  • Allergies: Allergic reactions to pollen, dust, or pet dander can cause conjunctivitis.
  • Irritants: Exposure to irritants like smoke, chemicals, or contact lenses may trigger inflammation.

Clinical Features

  • Red bloodshot eye
  • Itchy or gritty sensation
  • Discharge

Does not cause pain, photophobia or reduced visual acuity.

Bacterial conjunctivitis

  • Presents with purulent discharge - usually worse in the morning.
  • Highly contagious - usually starts in one eye and spreads

Viral conjunctivitis

  • Common usually presents with clear discharge
  • A/w other viral infection symptoms - dry cough, Sore throat, blocked nose
  • Pre-auricular lymph nodes
  • Also contagious

Investigations

Rule out sinister causes of Acute Red Eye

Causes of an acute painful red eye include:

  • Acute angle-closure glaucoma
  • Anterior Uveitis
  • Scleritis
  • Corneal abrasions or ulceration
  • Keratitis
  • Foreign body
  • Traumatic or chemical injury

Causes of an acute painless red eye include:

  • Conjunctivitis 
  • Episcleritis
  • Subconjunctival haemorrhage

Management

  • Usually resolves in 1-2 weeks without needing treatment

  • Hygiene measures can reduce spreading

  • Cleaning eyes with cooled boiled water and cotton wool

  • Chloramphenicol or fusidic acid eye drops if necessary

  • Antihistamines for allergic cause can be helpful

Complications/red Flags

Neonates <1 month

Need urgent ophthalmology assessment May be caused by gonococcal infection with can cause serious complications (inc vision loss)

If bacterial cause is recurrent, and confirmed on swabs, consider chlamydial cause - refer to GUM