This patient most likely has viral conjunctivitis. Other possible diagnoses include allergic conjunctivitis (usually with pruritus), atopic conjunctivitis (usually with eczema), bacterial conjunctivitis (usually with purulent discharge), medication toxicity (ex. patient on chronic IOP lowering drops) and pediculosis (lice and chronic follicular conjunctivitis).
Viral conjunctivitis is an inflammatory response to infection of the conjunctival tissues surrounding the globe and lids by a virus. The most common cause of viral conjunctivitis is adenovirus. Other causes include coxsackie virus, enterovirus, molluscum contagiosum and systemic viral syndromes such as measles, mumps, influenza and rhinovirus. Viral conjunctivitis most commonly affects patients with URI symptoms or with a history of sick contacts. It usually starts in one eye and develops in the other eye a few days later. Herpetic conjunctivitis has distinct findings but in its mildest form can mimic typical viral conjunctivitis.
Ocular findings include conjunctival hyperemia, chemosis and hemorrhages, follicular conjunctival reaction, epiphora, preauricular adenopathy, corneal subepithelial infiltrates, edematous eyelids, conjunctival membranes or pseudomembranes, corneal epithelial defects,
Other findings in viral conjunctivitis can include subepithelial infiltrates, conjunctival membranes or pseudomembranes. Visual acuity is minimally affected in viral conjunctivitis. Diagnosis of viral conjunctivitis is usually based on history and exam. Fluorescein can help detect corneal epithelial defects. Cultures should only be performed if purulent discharge is present or the conjunctivitis is chronic.
Treatment of viral conjunctivitis is supportive with artificial tears and cool compresses. Topical antibiotics are not needed unless a bacterial etiology is suspected. Corticosteroid drops are usually avoided but can be helpful in the convalescent period in the most severe cases (evidence of membranes/pseudomembranes). Topical anesthetics should not be used as these can impede healing. Patients that use contact lenses should avoid lens wear until signs and sxs have resolved. Prognosis of viral conjunctivitis is very good as most patients will have spontaneous resolution in two weeks. Membranes/pseudomembranes may cause permanent conjunctival scarring and chronic subepithelial infiltrates in the visual axis can impair vision. Hand washing and other disinfectant techniques are important to prevent transmission.