Red eye Corneal ulcer Corneal abrasion Conjunctivitis Poor fit Yes i i i No I No Contact lens wearer ? ^(consult) Known systemic disease ? Fluorescein staining? Yes Corneal abrasion ^ Foreign body Chemical Allergic conjunctivitis Yes No Yes I Yes Yes Itching ? No Blepharitis Yes Iritis Conjunctivitis Vitritis ( Tables 27.1 and 27.3) Yes Lid swelling? Fever ? * * Periorbital cellulitis Orbital cellulitis EKC Endophthalmitis No V No Phlyctenule Episcleritis Chemical Chemosis? Yes i \ t Iritis Episcleritis/scleritis Herpes Foreign body Abrasion Dry eye < Focal injection? No i r Phlyctenule Trichiasis Glaucoma (rare) Endophthalmitis Infectious conjunctivitis Dry eye syndrome Systemic disease FIGURE 27.2 Diagnostic evaluation of red eye EKC, epidemic keratoconjunctivitis In the absence of cornea/conjunctiva abrasion, foreign body, and trichiasis, the painful red eye caused by trauma may have iritis This may not present for up to 72 hours after the trauma Photophobia and vision blurring may also occur The ipsilateral pupil may be smaller, larger, misshapen, or react poorly, from trauma to pupillary sphincter muscle ( Fig 27.5 ) Occasionally, one will see a cloudy inferior cornea caused by the deposition of inflammatory cells and debris on the inner surface (keratoprecipitates) Hypopyon, layered pus or white cells in anterior chamber, may be seen in extremely severe iritis Iritis may also occur in association with systemic disease or as an isolated idiopathic ocular finding Iritis (anterior uveitis) associated with juvenile idiopathic arthritis is characterized by the distinct absence of signs or symptoms until the disease has progressed significantly, thus underscoring the need for routine screening of these patients Other systemic causes of iritis include sarcoidosis, tuberculosis, inflammatory bowel disease, collagen vascular disorders, systemic lupus erythematosus, granulomatosis with polyangiitis (formerly referred to as Wegener), tubular interstitial nephritis uveitis syndrome, and leukemia Traumatic iritis and nontraumatic iritis often are indistinguishable except by history All causes of iritis, regardless of the etiology, require ophthalmologic consultation and followup The diagnosis of iritis requires slit-lamp examination by a skilled provider Prescription of topical steroids should only be provided in consultation with an ophthalmologist FIGURE 27.3 Corneal ulcer (arrow) FIGURE 27.4 Bulbar conjunctival injection in patient with Kawasaki disease FIGURE 27.5 Anisocoria with traumatic uveitis Episcleritis and scleritis may also cause a painful red eye Episcleritis is more commonly seen in young adults while scleritis occurs more commonly in adult females Although episcleritis is usually an isolated, self-limited ocular abnormality, scleritis is often associated with an underlying systemic disease, particularly the collagen vascular disorders Both entities may present with focal or diffuse inflammation A focal nodular or diffuse elevation may be seen The eye is often tender, especially with scleritis, where the inflamed area may have a bluish hue There may also be pain on attempted movement of the eye Scleritis is much less common than conjunctivitis and episcleritis Diagnosis and treatment require slit-lamp examination and ophthalmologic consultation Herpetic corneal infection is another cause of painful red eye Herpes simplex virus infection can present as vesicular rash involving the eyelids or as a dendritic keratitis involving the cornea causing eye pain, tearing, photophobia, and decreased vision Often there is a history of previous episodes Fluorescein staining of the cornea may reveal a linear branching pattern in dendritic keratitis ( Fig 123.9 ) or amoeba-shaped corneal ulcer with dendritic edge in a geographic ulcer Herpetic corneal ulcers require urgent treatment and ophthalmology referral as soon as possible to prevent corneal scarring and vision loss Herpes zoster ophthalmicus presents with a vesicular dermatomal skin rash along the first division of the 5th cranial nerve The rash usually does not cross the midline Corneal involvement may follow skin rash by several days to months If eye pain is relieved by a drop of topical anesthetic (see Chapter 114 Ocular Trauma ), the patient most likely has a surface problem such as foreign body or corneal abrasion If the pain is not relieved and periorbital swelling and fever are present, the red eye may be caused by periorbital or orbital cellulitis which is emergent condition (see Chapter 123 Ophthalmic Emergencies ) Eye pain, watery discharge, hyperemia, chemosis, and marked lid swelling also may be associated with epidemic keratoconjunctivitis (EKC) secondary to adenovirus (Fig 123.7 ) When questioned further, patients may reveal that they actually have a sandy foreign body sensation rather than true ocular pain Pseudomembranes are a fairly diagnostic sign when present ( Fig 27.1 ) Lowgrade fever and tender preauricular adenopathy may also occur, making it difficult to distinguish EKC from periorbital cellulitis EKC usually affects the eyes consecutively and bilaterally as opposed to the unilateral nature of periorbital cellulitis There also may be associated prominent photophobia and tearing in adenoviral conjunctivitis, which is not usually seen in cellulitis Itching is another important diagnostic symptom When it is associated with conjunctival edema, giving it the appearance of a blister-like elevation (chemosis, Fig 123.10 ), one should suspect allergic conjunctivitis Seasonal allergic conjunctivitis, a type I, IgE-mediated hypersensitivity reaction to allergens such as pollen, is the most common type of ocular allergy It is often seen in patients with atopic disease Both eyes are usually affected Tearing, burning, and mild eyelid swelling may be present Itching and a burning sensation can be associated with blepharitis, an idiopathic disorder in which there is suboptimal flow of secretions from the meibomian glands in the eyelids resulting in an abnormal tear film and rapid corneal desiccation Blepharitis may present as acute or chronic bilateral eye irritation Symptoms are aggravated by activities associated with prolonged staring and decreased blinking such as reading, television or computer viewing, and playing video games Spending time outside on windy days can also provoke symptoms To compensate for the tear film deficiency, reflexive excess tearing may occur from the lacrimal gland Patients may have photophobia and a sandy foreign body sensation The most characteristic sign is erythema of the eyelid margins and flaking and crusting at the base of the eyelashes ( Fig 27.6 ) Chronic skin changes also include eyelid thickening Left untreated, the reduced flow of the meibomian glands may allow for proliferation of the coagulasenegative staphylococci that normally colonize the area This overgrowth may lead to an immune response causing an inflamed elevated white spot(s) on the conjunctiva (phlyctenule) or peripheral corneal infiltrates associated with a red eye Slit-lamp examination is helpful in making these diagnoses, particularly to assess for corneal involvement