Symptoms of acute conjunctivitis include an irritated red eye with a watery or purulent discharge.
There are a range of causes of acute conjunctivitis, including allergy, bacterial or viral infection, mechanical stress, and irritation by toxic chemicals or medication.
Allergic conjunctivitis is usually bilateral with watery discharge and itching.
Treatment for allergic conjunctivitis includes topical mast cell stabilisers and antihistamines; bacterial conjunctivitis treatment includes topical antibiotics; viral conjunctivitis requires symptomatic treatment.
Bacterial and viral conjunctivitis is highly contagious; measures to prevent spread of infection should be considered.
Conjunctivitis is the inflammation of the lining of the eyelids and eyeball caused by bacteria, viruses, allergic or immunological reactions, mechanical irritation, or medicines.
History and exam
Key diagnostic factors
- presence of risk factors
- watery discharge
- ropy, mucoid discharge
- purulent discharge
- itching predominant symptom
- red eye
- eyelids stuck together in morning
- tender, pre-auricular lymphadenopathy
Other diagnostic factors
- conjunctival follicles
- swollen eyelids
- superficial punctate keratopathy
- unilateral symptoms and signs
- use of medications that may lead to eye irritation
- contact lens use
- corneal subepithelial infiltrates
- corneal pannus
- vesicular skin rash
- symptoms and signs of related systemic disease
- exposure to infected person
- infection in one eye
- environmental irritants
- allergen exposure
- concurrent infection
- camps, swimming pools, military bases
- Asian or Mediterranean boy or young man
- atopic dermatitis
- contact lens use
- ocular prosthesis
- trauma: mechanical, chemical, or ultraviolet
- recent surgery or exposed sutures
- hot, dry environment
- allogeneic stem cell transplantation
- Stevens-Johnson syndrome/toxic epidermal necrolysis (TEN)
- prior infection with herpes simplex virus
- in neonate: vaginal delivery
- oculogenital spread
- hay fever
- topical eye medicine
- oral antihistamine/anticholinergic drugs
- history of rheumatological disease
- dysthyroid states
- immunocompromised state
- nasolacrimal duct obstruction
- abnormality of supporting structures of the eye (adnexa)
- severe tear deficiency
1st investigations to order
- rapid adenovirus immunoassay
Investigations to consider
- cell culture
- special stains (Gram, Giemsa)
- polymerase chain reaction
- ocular pH
- allergy skin testing
- tear immunoglobulin E level
allergic conjunctivitis (seasonal/perennial)
chlamydial conjunctivitis (inclusion)
contact lens related
Robert Sambursky, MD
Manatee Sarasota Eye Clinic & Laser Center
RS is employed by Lumos Diagnostics and serves on the board of Lumos Diagnostics, Visus Therapeutics, and PPK Solutions.
Dr Robert Sambursky would like to gratefully acknowledge Dr Lee Raykovicz, a previous contributor to this topic.
LR is Director of Clinical Relations, Rapid Pathogen Screening, Inc.
Michael Ehrenhaus, MD
Cornea, External Disease & Refractive Surgery
Long Island College Hospital Eye Center
Assistant Professor of Ophthalmology
SUNY Downstate Medical Center
ME declares that he has no competing interests.
Scott Fraser, MD, FRCS (Ed), FRCOphth
Sunderland Eye Infirmary
SF declares that he has no competing interests.
- Dry eyes
- Seasonal allergic conjunctivitis (hay fever conjunctivitis); perennial allergic conjunctivitis
- Conjunctivitis medicamentosa (also Dermatoconjunctivitis medicamentosa)
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