The patient complains of a red eye, a sensation of fullness, burning, itching, or scratching, and perhaps a gritty or foreign body sensat ion and tearing or purulent discharge and crusting or mattering. Examination discloses generalized injection of the conjunctiva, thinning out towards the cornea (localized inflammation suggests some other diagnosis such as a foreign body, episcleritis, or a viral or bacterial ulcer). Vision and pupillary reactions should be normal and the cornea and anterior chamber should be clear. Any discomfort should be temporarily relieved by instilling topical anesthetic solution. Deep pain, photophobia, decreased vision and injection more pronnounced around the limbus (ciliary flush) suggest more serious involvement of the cornea and iris.
Different symptoms suggest different etiologies. Tearing, preauricular lymphadenopathy and upper respiratory symptoms suggest a viral conjunctivitis. Pain upon awakening with lid crusting and a copious purulent exudate suggests a bacterial conjunctivitis. Few symptoms upon awakening but discomfort worsening during the day suggests a dry eye. Little conjunctival injection with a seasonal recurrence of chemosis and itching, and cobblestone hypertrophy of the tarsal conjunctiva suggests allergic (vernal) conjunctivitis. Physical and chemical conjunctivitis, caused by particles, solutions, vapors, natural or occupational irritants that inflame the conjunctiva, should be evident from the history.
What to do:
Instill proparcaine anesthetic drops (Alcaine, Ophthaine) to allow for a more comfortable exam and to help determine if the patient's discomfort is limited to the conjunctiva and cornea or, if there is no pain relief, that the pain comes from deeper eye structures.
Examine the eye, including visual acuity, inspection for foreign bodies, pupillary reaction fundoscopy, estimation of intraocular pressure by palpation of the globe above the tarsal plate, slit lamp examination (when available), and fluorescein and ultraviolet or cobalt blue light to assess the corneal epithelium.
Ask about and look for any rash, arthritis, or mucous membrane involvement which could point to Stevens-Johnson syndrome, Kawasaki's, Reiter's, or some other syndrome that can present with conjunctivitis.
For bacterial conjunctivitis, start the patient on warm compresses and seven days of topical antibiotics such as erythromycin, sulfacetamide, tobramycin or gentamycin ointment (which transiently blurs vision) every 4 hours, or solutions such as sulfacetamide 10%, tobramycin 0.3% or ciprofloxacin every 2 hours, with oral analgesics as needed. If it is unclear whether the problem is viral or bacterial, it is safest to treat it as bacterial.
For viral and chemical conjunctivitis, use cold compresses and weak topical vasoconstrictors such as naphazoline 0.1% (Naphcon) every 3-4 hours, unless the patient has a shallow anterior chamber that would be prone to acute angle- closure glaucoma with mydriatics.
For allergic conjunctivitis, use cold compresses and topical decongestant- antihistamine combinations such as drops of naphazoline with pheniramine (Naphcon A) or naphazoline with antazoline (Vasocon A) every 3-4 hours. Topical corticosteroid drops provide dramatic relief, but prolonged use increases the risk of opportunistic viral, fungal and bacterial corneal ulceration, cataract formation and glaucoma. If a severe contact dermatitis is suspected, then a short course of oral prednisone would be indicated.
If the problem is dry eyes (keratoconjunctivitis sicca) use methylcellulose (Dacriose) artificial tear drops.
Have the patient follow up with the ophthalmologist if the infection does not clearly resolve in 2 days. Obtain early consultation there is any involvement of cornea or iris.
What not to do:
Do not forget to wash your hands and equipment after examining the patient, or you may spread herpes simplex or epidemic keratoconjunctivitis to yourself and other patients. Also, do not forget to instruct the patient on the importance of hand washing and separation of towels and pillows for ten days after the onset of symptoms.
Do not patch an affected eye, as this interferes with the cleansing function of tear flow.
Do not give steroids without arranging for ophthalmologic consultation, and never give steroids if a herpes simplex infection is suspected.
Warm compresses are soothing for all types of conjunctivitis, but antibiotic drops and ointments should be reserved for when bacterial infection is likely. Neomycin-containing ointments and drops should probably be avoided, because allergic sensitization to this antibiotic is common. Any corneal ulceration requires ophthalmological consultation. Most viral and bacterial conjunctivitis will resolve spontaneously, with the possible exception of staphylococcus, meningiococcus, and gonococcus infections, which can produce destructive sequelae without treatment.
Most bacterial conjunctivitis is caused by Streptococcus pneumoniae, Haemophilus aegyptus and Staphylococcus aureus. Routine conjunctival cultures are seldom of value, but you should Gram stain and culture a copious purulent exudate. Neisseria gonorrhoeae infection confirmed by Gram-negative intracellular diplococci on Gram stain requires immediate ophthalmologic consultation. Corneal ulceration, scarring and blindness can occur in a matter of hours. Chlamydial conjunctivitis will usually present with l